Cathedral City City Council
September 24, 2025

INTRODUCTION
With the majority of United States and the District of Columbia having legalized recreational and/or medicinal cannabis, a significant problem has emerged in several regions related to the mitigation, regulation, and assessment of the odor generated by cannabis cultivation and processing activities.

This issue is complicated as odors are subjective, and the nature and composition of cannabis odor is highly variable. In addition, different societies have inherently different levels of acceptance for odors in their communities. Regulators at the state, regional, and local levels are attempting to deal with these complex issues through a combination of permitting, land use, and nuisance rules. The cannabis odor situation in Cathedral City is no different, and currently, the municipality is working to find a balance between responsible cannabis cultivation and impacted citizens.

It is estimated that 70% to 80% of the complaints issued to regulatory agencies concerning air pollution involve an odor component (Leonardos, 1996; Nicell, 2009; Shusterman, 1992). Odor is not regulated as a pollutant by the Clean Air Act; however, may be regulated at the state or local level through various types of “odor law,” whether it is called an ordinance, rule, regulation, or policy. “Odor laws” address community odor issues in several ways and methods that utilize various criteria:
1) Annoyance (subjective categories),
2) Complaint criteria (numbers of complaints),
3) Ambient odor concentration/detection threshold (various methods), 4) Ambient odor intensity (analytical testing),
5) Ambient odorant criteria (i.e. chemical surrogate),
6) Episode duration-frequency criteria (“odor-hours”).
7) Source emission criteria (chemical surrogate at source), and 8) Best available control technology criteria (i.e. industry standard).

In the absence of "odor laws," citizens and communities often find remedies and relief in basic common-law nuisance lawsuits. Due to this regulatory approach, sources of odors may face complex permitting scenarios when addressing potential offsite odors/impacts.

SCS Engineers (SCS) has drafted this document for the City of Cathedral City (City) for the purposes of the development and implementation of effective cannabis odor control strategies. This report intends to provide guidance to City regulators regarding the current state of understanding relative to cannabis odor emissions, methods for assessing cannabis odors, and to provide guidance for regulators in establishing odor rules and permitting guidance relative to cannabis cultivation operations.

Cathedral City – Regulatory Review - Cannabis Odor Control

REGULATORY REVIEW AND BEST PRACTICES ASSESSMENT
Regulatory Review Summary
Background
Cathedral City (City) is the home to a growing cannabis industry totaling over 100 active licenses. The City’s current code outlines a general expectation that odors not be detectable beyond the cannabis business, but it fails to include the permitting, review, and enforcement standards necessary to uphold and verify compliance with City expectations. There are no required odor abatement plans, third-party reviews, regular inspections, or performance testing, making it difficult for the City to hold operators accountable when odors persist. In response, the City conducted an internal review of the current cannabis processes and regulations that revealed the need for a formal odor abatement plan, defined performance standards, and objective enforcement tools. These findings led to the initiation of a cannabis moratorium.

Research Process
On February 26, 2025, the City Council extended the cannabis moratorium by 10 months and 15 days. City staff initiated a review of 84 California cities and counties permitting cannabis cultivation that was later narrowed down to 15 cities and 3 counties that provided insight into one or more of the focus areas included zoning, odor control, licensing, and enforcement.

The research focused on how different cities handled issues like permitting, zoning and separational requirements, operational limits, odor definitions, mitigation requirements, enforcement, and response to complaints. The City also initiated a records request with the Department of Cannabis Control (DCC) to assess how many large-scale indoor cannabis cultivation facilities existed statewide.

DCC research identified six licensed large-scale indoor cultivation facilities (≥ 22,000 SF canopy), which are smaller than Cathedral City’s 200,000+ square foot C4 Industry facility.

Findings
The City’s research focused on Palm Springs, Desert Hot Springs, Coachella, and local communities within the Coachella Valley for better understanding of how each jurisdiction manages cannabisrelated odor issues to support the development of a clear, enforceable cannabis odor control permitting process for the City that aligns with the best practices across California. Findings can be summarized into the following categories:

Zoning Requirements
Most jurisdictions permit cultivation, manufacturing, and testing only in industrial zones and have allowed dispensaries in both industrial and retail areas. The common zoning practices among these cities minimize cannabis-odor impacts by maintaining a zoning buffer requirement between cannabis operations and residential or sensitive land use areas such schools and daycares. Research confirmed that the City is an outlier by allowing cultivation and manufacturing in commercial zones, increasing the potential for odor complaints and conflict with neighboring zones.

Cathedral City – Regulatory Review - Cannabis Odor Control

Separation Requirements
Standard separation buffers vary across jurisdictions. For example, State law mandates 600 feet from schools/daycares/youth centers but local jurisdictions, such as Palm Springs (1,000 ft from residential), Palm Desert (1,500 ft between retailers), Long Beach (1,000 ft between dispensaries), and Grover Beach (100 ft from residential) implement stricter standards. The City does not enforce specific buffer distances between cannabis businesses and residential properties or between cannabis businesses themselves, beyond what is required by state law. The lack of the City’s separation standards enables cannabis businesses to operate closer to homes and sensitive land use areas as well as potentially create cumulative impact odor events.

Odor Control Standards
The City Code requires cannabis businesses to prevent odors from being detectable outside, but there is no requirement to submit odor abatement plans, no standard equipment guidelines, and no formal review of systems before or after installation. Most cities require cannabis businesses to install odor mitigation systems such as air filtration or negative pressure systems. Palm Springs, Coachella, and Desert Hot Springs require businesses to submit odor abatement plans, typically prepared by licensed professional engineers or certified industrial hygienists. Adopting an odor abatement standard like other cities would allow the City to have systems that are well-designed and effective.

Odor Definition
The City relies on a general nuisance definition, with odors considered a violation after three verified complaints or if observed by City staff. There are no objective tools or thresholds for measuring odor within the City ordinance. Cannabis odor is not defined precisely in most cities, but Palm Springs and Coachella use threshold-based standards involving olfactometers. Coachella also defines “odor threshold concentration” using standards from the American Society for Testing and Materials (ASTM). The Nasal Ranger is used in El Dorado and Santa Barbara County.

Enforcement & Compliance
The City can respond to complaints but does not require businesses to modify or upgrade systems following a violation. There’s currently no link between confirmed violations and CUP compliance or enforcement actions. Palm Springs uses an escalating fine structure and can revoke permits after repeated noncompliance. Desert Hot Springs authorizes daily fines for violations, while some cities require businesses to respond to complaints within specific timeframes (7–30 days).

Permitting
The City currently does not require odor abatement plans and lacks an inspection process for odor systems. Palm Springs integrates odor plan review into its CUP process with expert validation. Grover Beach requires an annual certification of odor control systems.

SCS recommends an odor abatement plan requirement for all cannabis business licensure, certified by either a Certified Industrial Hygienist or Professional Engineer. Recommendations for the framework of an OAP is outlined in Section 2.2.1.

Cathedral City – Regulatory Review - Cannabis Odor Control

Case Studies & Relevance to the City of Cathedral City
Some cities have odor control expectations written into their codes, but only a few have detailed processes for plan review, inspection, and ongoing compliance. Cities like Palm Springs and Coachella offer structured odor mitigation plan requirements but lack objective enforcement metrics.

Santa Barbara County’s recent code revisions use olfactometers but nevertheless rely on subjective assessments and complaints to drive responsive action.

Cathedral City would benefit from a structured odor mitigation plan and objective enforcement measures given the City is unique in how it permits cannabis in commercial zones and lacks measurable odor standards to highlight regulatory gaps.

Using a performance based standard places the onus on the cannabis operator/business and evaluates the system efficacy with empirical data.

Regulatory Review Summary Conclusion
When City staff compared local cannabis regulations across 15 cities and 3 counties, it was discovered that some jurisdictions have established odor control permitting processes and enforcement models, yet none had adopted objective standards for measuring cannabis odor.

Most cities rely on complaint-driven or subjective assessments, limiting consistency and effectiveness. Other jurisdictions require detailed odor abatement plans as part of the permitting process, along with engineering input and equipment specifications. These gaps highlight why the City needs expert support to create enforceable, measurable standards, outlines for what must be included in odor abatement plans, and develop checklists and procedures for inspection and enforcement.

Cathedral City – Regulatory Review - Cannabis Odor Control

Odor Control Plan Development
Odor abatement plans (OAP) contain procedures to reduce odors and include methods for managing odor complaints. The following subsections describe typical OAP contents.

Cannabis Facility Type, Odor Generating Potential & OAP Requirement
The following is a description of the various types of cannabis-related facilities, their potential for nuisance odor generation and whether having an OAP is recommended.

Cultivation Facility: Licensed premises where cannabis is cloned, propagated, grown, harvested, dried, cured, and trimmed. May include nursery (juvenile) and mature plants, or a mix of both.

Cultivation may occur indoors, outdoors, or in mixed-light environments such as greenhouses. This land use encompasses both mature plant production and nursery operations for immature plants or clones, and may involve the use of artificial lighting, environmental controls, and irrigation systems.

This facility type has a high odor generating potential and requires a robust OAP for mitigating odors generated by facility operations with an OAP checklist found in the Appendix E.

Manufacturing Facility: Licensed premises where cannabis is transformed or processed into cannabis products through chemical extraction, infusion, compounding, blending, packaging, or other preparation processes. Products may include pre-rolling, concentrates, edibles, topicals, tinctures, capsules, beverages, or other items intended for commercial sale and consumption. This facility type has a wide range of odor generating potential dependent on the nature of their operations. This type of facility requires a robust OAP for mitigating odors generated by facility operations with an OAP checklist found in the Appendix E.

Consumption Lounge: Licensed commercial establishment where adults may legally purchase and consume cannabis products on the premises in a designated, controlled environment. These lounges may be co-located with a licensed cannabis retailer or operate as standalone businesses, subject to Cathedral City authorization and compliance with state law. This facility type has a high odor generating potential and requires a robust OAP for mitigating odors generated by facility operations with an OAP checklist found in the Appendix E.

Dispensary (Retail Storefront): Licensed commercial establishment where cannabis and cannabis products are sold or delivered directly to adult-use consumers or medical patients. Retail operations may be conducted through a storefront (walk-in sales) and/or non-storefront delivery services, depending on license type and local authorization. Odor potential for this facility type is low-tomoderate, depending on product packaging, quantity and facility operations. An OAP for this facility type is recommended, with an OAP checklist found in the Appendix E.

Testing Laboratory: Licensed, independent facility authorized to receive and analyze cannabis and cannabis products for regulatory compliance. Testing includes, but is not limited to, analysis for potency, residual solvents, pesticides, heavy metals, microbial contaminants, moisture content, and terpene profiles, in accordance with state-mandated laboratory protocols. Odor potential for this facility type is low, and SCS does not recommend the City require an OAP for testing laboratories.

Cathedral City – Regulatory Review - Cannabis Odor Control

Odor Abatement Plan Outline
The following is an example outline of an effective and comprehensive odor abatement plan for a cultivation or processing facility. Appendix E includes an Odor Abatement Plan template checklists for five facility types: cultivation/processing, dispensaries (Retail Storefronts), and consumption lounges.
1) Introduction and Source Identification
 Facility Name
 Facility Address / Assessor’s Parcel Number(s) (APN)
 Vicinity & Zoning Map
 Site Map
 Process Flow Diagram
 Description of Operations and Layout
2) Description of Odor Emitting Activities or Processes  Identification of Odor Emitting Activities and Processes  Identification of Odorants
 Material Storage/Waste Generation
 Processes
 Operational Schedules
 Fugitive Sources
3) Description of Methods used for Odor Control
 Administrative Controls
 Engineering Controls
 Process Parameters for Proper Operation
 Maintenance Requirements
 Staff Training
 OAP plan certification by Certified Industrial Hygienist (CIH) or Professional Engineer (PE) 4) Complaint Management Procedures
 Facility Contact Information
 Complaint Management System
 Procedures for Response
 Community Outreach, if applicable
5) Corrective Action Plan, if required
Facility Description and Location
A site-specific odor abatement plan includes a description of the facility and surrounding area. The facility information includes a summary of the property size, location within the regional zoning, descriptions of the surrounding properties and land uses, dimensioned proximity to sensitive receptors, such as residential areas, schools, hospitals, daycares, and other public facilities, descriptions of type of activities taking place onsite, and a general summary of onsite structures. The presence of other potential odor-generating sites in the vicinity of the facility should also be noted.

Cathedral City – Regulatory Review - Cannabis Odor Control

Odor-Emitting Sources
The odor abatement plan includes a list of odor generating processes. The following information, where available, for the identified processes is recommended for inclusion. • Description of odor characteristics
• Odor release method (vent, building fugitives, etc.)
• Odor Controls, if any, related to the source
• Location of odor release point/proximity to sensitive neighbors • Operating schedule (continuous, intermittent, seasonal, how many weeks per each stage) Odor Control Strategies and Best Management Practices (BMPs) The odor abatement plan describes the technologies used to mitigate odors from odor generating sources or explains why odor control is not warranted. The Plan includes a description of the odor control technology, a summary of operating and maintenance requirements for proper operation of the odor control system components, and best management practices (BMPs) the facility implements to reduce potential for offsite odor impacts. The submitted OAP shall conform in design with the City’s requested criteria and reflect a design that echoes the regulatory framework requirements.

Complaint Management System
The odor abatement plan includes procedures for responding to odor complaints. This includes identification of site-specific personnel responsible for managing complaints, and a tiered approach for responding to and mitigating complaints. An example of sections that may be included in the complaint management system is provided below.
• Method for Submittal of Complaints
o Phone, Email, Web application
• Roles and Responsibilities of Facility Staff
• Compliance Response Process
o Level 1 Response – Initial Assessment and Corrective Actions o Level 2 Response – Diagnostic Assessment and Corrective Actions o Level 3 Response -- Analytical Assessment and Corrective Actions o Level 4 Response -- Comprehensive Controls Analysis and Corrective Actions • Maintain complaint records for a minimum of five (5) years for historic analysis and data trending.

Cathedral City – Regulatory Review - Cannabis Odor Control

Section 2.0 Summary and Recommendations
• We recommend all cannabis operations submit an Odor Abatement Plan (OAP) as part of the licensing process.
o The OAP should be prepared and certified by a Certified Industrial Hygienist (CIH), Professional Engineer (PE), or otherwise qualified expert. • We recommend the City integrate odor control requirements into the Conditional Use Permit (CUP) process.
o We recommend pre-occupancy inspections and annual re-certification of odor control systems.
• We recommend the City establish clear zoning and separation standards to reduce odor conflicts.
o New cultivation and manufacturing operations should be prohibited in commercial and residential zones.
o Existing facilities in commercial zones should be subject to enhanced odor mitigation requirements to meet no detectable and offensive odor at property line standards by a reasonable person of normal sensitivity. o We recommend implementing separation buffers (e.g., 1,000 feet from residential areas) and 500 ft between licensed businesses. • We recommend adopting objective odor definitions and measurement tools to support enforcement.
o We recommend defining “odor threshold concentration” using ASTM or similar recognized standards.
o We recommend inspectors be trained to detect and differentiate cannabis related odors from other local odor sources for field-based odor assessments by staff. • We recommend cannabis businesses maintain a structured, tiered complaint response process.
o We recommend operators document all complaints and resolutions and provide records to the City upon request.
• We recommend strengthening enforcement mechanisms to maintain compliance. o Fines should escalate with repeated violations or failure to meet OAP requirements.
o We recommend linking OAP compliance to license renewals and CUP conditions.

Cathedral City – Regulatory Review - Cannabis Odor Control

ODOR CONTROL TECHNOLOGY EVALUATION
There are various odor control technologies currently on the market and many others are being vetted for use in odor mitigation from cannabis operations. From enclosed spaces, the technology of choice continues to be scrubbing the effluent point through the use of carbon adsorption technologies and/or oxidation within effluent conveyance prior to release to atmosphere.

Vapor Phase odor neutralizers have been used with some success in cultivation facilities, but this technology has limitations and is generally not received favorably by the public. We recommend that the City prohibit the use of vapor phase systems as an odor control technology for cannabis operations, as these systems have increasingly become a source of community complaints and public opposition.

Carbon adsorption systems with various pretreatment options such as Photo Catalytic Oxidation (PCO) have also been shown to be capable of significantly reducing odor emissions from cultivation and manufacturing. Air scrubbing technologies come with some drawbacks such as a high capital expense to achieve adequate coverage/treatment depending on the method of use, as well as necessitating significant power consumption.

To be effective, odor reduction should be designed specifically to the type of source, facility structure, as well as the chemical composition of the odors. The first step to controlling odor typically requires capturing and transporting the odorous compounds from the source to the chosen odor reduction device. These methods vary based on source and business type.

Capturing odors from cannabis operations will vary depending on facility type. The transportation physics of odors from outdoor cultivation are different from those produced within an enclosed or semi-enclosed space. Similarly, odors and odor generating potential from a cannabis processing facility, where there may be a lot of movement between rooms and the building envelope via doors and HVAC systems, will vary from a retail storefront with sealed and packaged goods.

Odor Control Technologies
To achieve odor control, the chemical nature of the odor compounds can be changed to make them less odorous, the odorous compounds can be removed, or other compounds can be added to neutralize the odor perception character. A brief description of odor control technologies is provided below and additional details, including pros and cons of each, are provided in Table 1.

Change Chemical Structure
Changing the chemical structure of the odorant to a less odorous compound typically requires energy input (heat), an oxidizer, or biological activity to break the bonds between the elements of the odorous compound(s). Below is a list of some common technologies that change the chemical structure of odor compounds.
• Incineration such as combustion in flares or thermal oxidizers convert odorous compounds into carbon dioxide, nitrogen and water.
• Ozone is a powerful oxidant that can break apart odorous molecules through oxidation resulting in less odorous compounds.
• Non-Thermal Plasma uses electrically charged particles (plasma) that interact with odorous compounds and break them apart into less odorous compounds.

Cathedral City – Regulatory Review - Cannabis Odor Control

• Biological Filters use microorganisms that feed off odor-causing compounds to remove the odorant from the stream. The microorganisms biologically metabolize the compound releasing less odorous compounds.
• Photocatalytic Oxidation Photocatalytic oxidation (PCO) is a process that uses light energy to activate a catalyst to break down organic pollutants, bacteria, and viruses into harmless substances. This technology is widely used in air purification, water treatment, and selfcleaning surfaces.

Remove or Filter Odor
Removing or filtering the odor from the stream to be treated reduces the outlet or effluent concentration of odorous compounds. Below is a list of some common technologies that reduce odors through filtration.
• Adsorption captures odorous molecules in the pore space of adsorbent materials, such as activated carbon or zeolite, thus reducing the odors in the process stream. • Chemical/Wet Scrubbers use highly reactive chemicals such as acids, caustics, and surfactants to react with the odorous compounds and remove them from the process stream.

Neutralize or Mask Odor
Neutralizing and masking agents do not reduce or remove odorous compounds but rather alter how the odorous compound is perceived or not perceived by a person. Below is a list of some common technologies that reduce odors through vapor phase or misting systems. • Odor Neutralizers include compounds that adhere to odor molecules and change how the olfactory system recognizes the molecule, thus changing a person’s perception of odor to that stream.
• Masking Agents are similar to perfume in that they contain synthetic fragrance that are intended to “hide” odors. In some situations, the masking agents may bind to olfactory receptors thereby inhibiting the receptor’s ability to bind to odorous molecules.

Dispersion and Dilution
Primary factors that impact the transport of odor from a stationary source include the method of release of the odors, meteorological conditions, and the local topography/location of the facility.

Odors generated in the cannabis industry are emitted through various types of release points including stacks, vessel hatches/vents, and openings in buildings or enclosures, such as doorways and ventilation points. The following characteristics can impact the transport of odor from a release point.
• Odor Emission Rate (Odor Strength): The odor emission rate is a function of the concentration of the odorous stream and the volumetric flow rate of the release. In general, the higher the odor flux, the higher the ground-level odor concentration at a downwind location.
• Release Velocity: The velocity of a release impacts both the distance the odorous molecules travel and the potential for mixing/dilution with ambient air. The faster the release, the further the odors may travel, however, there is more potential for dilution/mixing with ambient air, which can decrease perceived ground-level impacts. In general, the higher the Cathedral City – Regulatory Review - Cannabis Odor Control

exit velocity, the lower the ground-level concentration may be at a downwind location; however, the distance odor can travel may be farther.
• Orientation of Release: The direction/orientation of an odor release impacts the transport of odor from the source. A vertical release provides the greatest potential for mixing and dilution. A horizontal release, such as a ventilation fan on the side of a building, will have limited vertical movement and reduced potential for mixing and dilution. Rain caps and hoods/enclosures around release points can also reduce the vertical movement and mixing of odor releases.
• Release Height: The height of the release will impact the amount of mixing/dilution with ambient air. A higher release point will generally lead to more mixing/dilution of an odorous source, which can decrease perceived ground-level odors. As will be discussed in Section

5.2.1, the release height can also be modified to avoid downwash from buildings, structures, and/or topography.
• Release Temperature: Although not as significant as release height or velocity, the temperature of an odorous source can impact the transport of odor. In general, the hotter the release temperature, the more buoyant the stream will be, which will increase the potential for mixing/dilution with ambient air.

The local meteorology impacts how odors are transported and mixed in the ambient air. Factors such as wind speed and direction and atmospheric stability will impact how odors are transported from a source.
• Wind Speed: Higher wind speed creates more mixing/dilution in the atmosphere and can reduce the potential for downwind odor impacts. Low wind speeds are more likely to create conditions for offsite odors.
• Wind Direction: The direction the wind blows directly impacts where the odorous release will travel. A turbulent condition, with frequent change in wind direction, can promote mixing/dilution of odors.
• Atmospheric Stability: The stability of the atmosphere influences the vertical movement of an emitted stream, which impacts the ability of the stream to mix/dilute with ambient air. In general, stable atmospheric conditions inhibit the vertical mixing of an emitted stream trapping odors close to the ground level and unstable conditions improve mixing and odor dilution.

The following figure depicts how weather affects the shape of an odor plume and the potential for mixing and dilution.

Cathedral City – Regulatory Review - Cannabis Odor Control

Figure 1: Behavior of Odor Plume as Function of Climatic Conditions (Douglas Hamilton, 2019) Stable atmospheric conditions commonly occur in the early morning hours, before sunrise, which is associated with an increase in potential for offsite odors during these periods.

Topography and larger facility structures, such as buildings and process/storage vessels, can alter the movement of wind/air around the facility and create additional surface roughness which can increase turbulence and impact the transport of odor from a source. • Topography: The topography surrounding a stationary source affects local wind patterns and surface roughness which impacts the direction odors are transported and the potential for mixing and dilution. As stated by Hamilton (Douglas Hamilton, 2019) obstacles to wind flow such as hills, trees and buildings increase the roughness of the terrain and, accordingly, the dispersion in the odor plume. Mixing is increased if winds carry the odor upslope or up-valley.

Downslope or down-valley winds lead to less dispersion and tend to concentrate odors in lower lying areas.
• Facility Structures: Similar to topographic features, facility structures alter the flow of wind around a source. As wind blows over/around a building/structure, a low-pressure area develops on the downwind side of the structure which pulls air toward the ground. Odor releases on the downwind side of this building/structure, will be affected and pulled toward the ground causing an increase in ground level odors. Increasing the release height of a source in the vicinity of a building is one method to counteract the effects of building downwash.

Use of Vegetative Buffers:

The use of vegetative buffers can provide several benefits related to the perception of odors downwind from cannabis operations. Vegetative Buffers are plantings of grasses, trees and/or shrubs that are strategically located around an odor source. Vegetative Buffers filter and trap dust, odor, particulate matter, and other molecules from the odor plume.

When used for their Vegetative Bio-Filtering and Windbreak capacities, Vegetative Buffers serve as a means of disruption of the odor plume. This allows heavier odorous molecules and odor-carrying material to settle out in areas of decreased air velocity and ‘dead spots’. Lighter molecules may lift Cathedral City – Regulatory Review - Cannabis Odor Control

up and away. Turbulence allows fresh air from above to mix with odorous air, diluting the concentration of odorous molecules toward or below odor detection thresholds.

Vegetative Filtering Concept – Vegetative Buffers, when used for their Vegetative Bio-Filtering and Windbreak capacities, are plantings of multiple rows of grasses, trees and/or shrubs that are strategically located around cannabis facilities. This active filtering helps to reduce the odor transport and increase dilution.

Visual Screening Concept – Vegetative Buffers, when used for their Visual Screening capacity, are plantings of single or multiple rows of grasses, trees and/or shrubs. Attractive trees and shrubs visually screen cultivation activities and can serve as landscape plants to beautify the facility.

Research concludes that sources judged as “attractive” have fewer odor complaints.

The following tables include an Odor Control Technology Summary in Table 1, explaining how various odor control technologies work, along with the pros and cons of the specific technology.

Table 2 details Odor Control Options Relative to Source Type, including source type, control method, footprint, known vendors, and capital expense.

Section 3.0 Summary and Recommendations
• SCS recommends the City maintain a technology-agnostic, performance-based approach to odor control (consistent with Section 4.1) to encourage innovation, site-specific flexibility, and alignment with evolving industry best practices. • We recommend facilities prioritize design features that enhance natural dispersion and dilution to reduce odor impacts, including:
o Vertical release configurations over horizontal or obstructed vents. o Optimized release height and velocity to promote ambient mixing. o Consideration of local terrain and building downwash effects when siting odor release points.
• SCS recommends operators evaluate the use of vegetative buffers as a supplemental mitigation strategy where feasible.
• We recommend that the City prohibit the use of vapor phase systems as an odor control technology for cannabis operations, as these systems have increasingly become a source of community complaints and public opposition.

Cathedral City – Regulatory Review - Cannabis Odor Control

Table 1 Odor Control Technologies Summary Table
Odor Control
Technology How It Works Pros Cons
Vapor Phase and
Misting Systems
(e.g., Ecosorb)
• Odor neutralizer chemical processes
involved are adsorption, absorption,
gas solubility and reaction:
o Contact: Proprietary chemical
usually consisting of essential
oils is delivered into an area
affected by odors and attracts to
odor molecules.
o Adsorption: Released material
attaches to odor molecules.
o Absorption: Neutralizer
surrounds odor molecules,
potentially neutralizing their
smell.
• Most vendors advertise natural ingredients –
no hazardous materials.
• Variety of application methods (vapor phase,
atomization, additive).
• Technology has been utilized by multiple odor
generating industries.
• On-going costs of the odor
neutralizer.
• Need to select the odor
neutralizer that best reduces
odors.
• If dispersing, need the odor
neutralizer plume to intersect
the odor plume.
• Difficult to quantify odor control
benefits.
• An additional emission source of
VOCs.
• The public may be opposed to
this type of control.

Masking Agents Chemicals are sprayed into the air, using synthetic fragrances to "hide" odors.
• Masking agents can come in many scents and
cover a broad range of odors
• They can be used outside facilities so they do
not impact finished goods and can come in
non-hazardous formulas
• Technology has been utilized by multiple odor
generating industries.
• Give an immediate cover to
odors, but the odors eventually
return as the fragrance and odor
molecules separate
• Many use hazardous chemicals
and are delivered by harmful
aerosols
• The relative effectiveness of this
type of technology is
questionable.

Chemical
Scrubbers /
Packed Tower
Wet Scrubber
Odors are combined with highly reactive
chemicals — acids, caustics, oxidizers,
and surfactants within a stack or tower.

The odorous compounds chemically
react with the solution, removing odors.
• Mechanics can be monitored and carefully
controlled.
• Systems are popular: known technology with
standard, “textbook” designs.
• System efficiency not dependent on nozzle
performance.
• Effective removal performance at high odor
concentrations.
• Expensive to build; must be
operated by trained personnel
and serviced in protective gear.
• Must be designed for a specific
application, with careful
considerations for dangerous
exhaust gas.

Cathedral City – Regulatory Review - Cannabis Odor Control

Odor Control
Technology How It Works Pros Cons
• Economically treats large volumes of air
• Relatively small footprint.
• Chemicals used are considered
reactive, hazardous, and must
be neutralized before disposal.
• Requires periodic cleanings.
• Relatively tall which may create
aesthetic issues.
• Requires efficient collection of
fugitive odors to be effective.

Adsorption
(Carbon Filters)
Gas particles from the air penetrate the
pores of an adsorbent material –
activated carbon, zeolite, or silica gel –
and removes odors from the air as it
passes through.
• Carbon is porous and has a large surface area,
which allows it to absorb odors in the air.
• Activated Carbon is a common adsorbent for
organic odor removal.
• Activated Carbon is used to remove sulfur
bearing compounds, aldehydes, and ketones.
• No chemical storage or recirculation pumps
• Simple operation and maintenance.
• Can remove a wider range of compounds than
wet scrubbers.
• Removes VOCs.
• Reversible in nature, which
allows odors to return if heated.
• Spent media disposal can be
messy and expensive, especially
when it contains hazardous
compounds.
• Adsorbents are consumable and
must be re-activated or
replaced.
• As influent odor increases,
carbon bed life expectancy
decreases.
• Systems can lose effectiveness
in highly humid environments.

Ozone
Generators create ozone molecules,
which are highly reactive to organic
material.
• Ozone is a powerful oxidant and anti-microbial.
• Ozone is fairly inexpensive to generate.
• Systems do not require filters.
• Can cause side effects if used
around people; treated areas
must be evacuated while in use
and hours afterward.
• Extremely caustic and could
damage cannabis products or
react to other chemicals in
treatment areas.
• Not effective on inorganic odors.

Cathedral City – Regulatory Review - Cannabis Odor Control

Odor Control
Technology How It Works Pros Cons
• Must be utilized within a duct or
stack to protect workers and
plants.

Biological Filters
Contaminated air passes through soil,
compost, wood chips, or other organic
material. As the odorous air flows
through the material, pollutants
(including odor molecules) transfer into a
thin biofilm on its surface.

Microorganisms in the biofilm eliminate
odors.
• Bacteria used are naturally occurring and can
metabolize many organic odor-causing
compounds.
• Works on odors that are biodegradable and
water-soluble.
• Easy to maintain and do not require chemical
addition.
• Can also remove VOCs.
• Large units with massive
footprints are needed to treat
airflow.
• Microbes must interact with the
odorous compounds over long
periods.
• Material must be replaced,
causing odors to go untreated
during downtime. Typical rebuild
is every 3-5 years.
• Installation costs can be
significant
Biological
Oxidation
(Scrubber)
Air is forced upward through an
adsorption column filled with synthetic
material. Water containing
microorganisms circulates through the
system, feeding off odor-causing
compounds and releasing cleaner air.
• These units work well to reduce odors caused
by ketones, alcohols, and ethers.
• Requires lower detention times (8 to 15
seconds for H2S) than bio filters.
• Media can be stacked higher.
• Inert media have a long bed life.
• Reduces potential footprint and requirements
for media replacement.
• Equipment needed to
recirculate water in
bioscrubbers makes for
expensive up-front and
operating costs.
• Requires selection of labdeveloped bacterial strain
specific to odor causing
chemicals.

Thermal &
Catalytic
Converters
The system burns odorous gases, The
gas is passed over (or through) catalytic
materials, converting residual gases into
compounds like carbon dioxide, nitrogen,
and water.
• There has been widespread development for
different catalytic mediums, mainly for
“reduction” and “oxidation” catalysts.
• Can potentially introduce toxins
and noxious substances into the
air.
• Even for well-designed and
operated systems, there is a
need for catalyst saturation and
sterilization.

Cathedral City – Regulatory Review - Cannabis Odor Control

Odor Control
Technology How It Works Pros Cons
Incineration
(Catalytic,
recuperative,
regenerative)
Odor-causing waste and gas are burned
at high temperatures supposedly
destroying process odors.
• Incinerators are one of the most positive and
proven methods for destroying VOCs with
efficiencies up to 99.9999%.
• Recuperative incinerators are usually more
economical than straight thermal incinerators
because they recover about 70% of the waste
heat.
• The incineration process is effective against
organic odors.
• Can also use modified incineration method to
produce Biochar with cannabis waste to reuse
as soil additive.
• High initial cost.
• Supplemental fuel requirement.
• Dangerously high temperatures
— usually around 1472°F
(800°C)— are needed to destroy
odors.
• Potentially introduces toxins and
additional odors into the
atmosphere.
• Additional air is sometimes
required and can cause volatile
gases to be released from the
waste gas.
• Not well suited to streams with
highly variable flow because of
reduced residence time and
poor mixing during increased
flow conditions.
• May not be suited for sulfur
containing compounds due to
formation of highly corrosive
acid gases.

Fabric Filter
(Mechanical
Shaker, PulseJet, Reverse-Air)
Gas is passed through a tightly woven
fabric, causing particulate matter (PM) in
the flue gas to be collected on the fabric
by sieving and other mechanisms.
• High collection efficiencies (95%+) of
particulates.
• Corrosion and rusting are not typical problems.
• Operation is relatively simple.
• Typically, does not require high voltage.
• Available in a large number of configurations.
• Useful for collecting particles with resistivities
either too low or too high for collection with
electrostatic precipitators.
• Potential for flammable dust.
• High temperatures require
special refractory mineral or
metallic fabrics which can be
expensive.
• Relatively high maintenance
requirements (e.g., periodic bag
replacement).
• Fabric life may be shortened at
elevated temperatures and in
the presence of acid or alkaline
particulate or gas constituents.

Cathedral City – Regulatory Review - Cannabis Odor Control

Table 2 Odor Control Options Relative to Source Type
Source Type Control Method Footprint Vendors Effectiveness (%)*Capital Expense High Low Controlled
Stacks (Indoor
Cultivation and
Processing
Facilities, Nonvented
Greenhouses)
Non-Thermal Plasma
Oxidation
Small - Placed on
Stacks IONOX 90% 65% Medium
Regenerative
Catalytic Oxidizers
(RCO)
Anguil 95% 80% High
Bio Filters

Large Footprint

Evoqua 95% 70% Medium
Envirogen 95% 70% Medium
Bio-Scrubber/Bio
Trickling Filter

Vertical Design

Evoqua 95% 70% Medium
Envirogen 95% 70% Medium
Chemical Scrubber
Horizontal or
Vertical Design,
Compact
Valkyrie System by
Streamline 95% 75% Medium
Molecular Filtration -
Carbon

Horizontal or
Vertical Design,

Carbon Bulk 95% 80% Medium
General Carbon 95% 80% Medium
Camfil 95% 80% Medium
Byers Scientific 95% 80% Medium
Multi Technology
Scrubber Systems
that include TiOx
Horizontal or
vertical Design Envinity Systems 98% 80% Medium
Vapor Phase
Neutralizer or Mask

Small footprint
OMI Not
Available
Not
Available Low
FogCo Not
Available
Not
Available Low
Cathedral City – Regulatory Review - Cannabis Odor Control

Source Type Control Method Footprint Vendors Effectiveness (%)*Capital Expense High Low Byers Scientific Not
Available
Not
Available Low
Vents
(Vented
greenhouses,
indoor
cultivation)
Internal Treatment -
Scrubber Towers Envinity, Camfil 95% 80% Medium
Misters Essential Oils Byers Scientific Not
Available
Not
Available High
Vapor Phase
Essential Oils OMI Not
Available
Not
Available Low
Iodine Based
Solution Fog Co Not Available
Not
Available Low
Fugitive
(All Source
Types)
Misters Small - 6'X6 Multiple Not
Available
Not
Available Low
Vapor Phase
OMI Not
Available
Not
Available Low
Fog Co Not
Available
Not
Available Low
Product
Storage/Waste
Treatment
Additive To Treated Chemical Tanks,
pumps
OMI Not
Available
Not
Available Low
Ph Control Chemical Tanks,
pumps
Various Not
Available
Not
Available Low
Talon Sulfide
Elimination System
Chemical Tanks,
pumps
Streamline Not
Available
Not
Available Low
* Values presented are from manufacturer literature and general research. SCS has not validated all of the listed specifications and ranges presented within cannabis operations.

Cathedral City – Regulatory Review - Cannabis Odor Control www.scsengineers.com

ODOR CONTROL PERMITTING PROCESS
Based on our comparative review of odor control permitting programs in peer jurisdictions and our direct experience developing odor abatement plans across the cannabis and broader industrial sectors, SCS recommends that the City adopt a permitting structure that clearly assigns the responsibility for demonstrating effective odor control to the cannabis operator. This approach promotes innovation, introduces accountability, and provides the regulatory flexibility needed to accommodate site-specific conditions. To support this structure, we recommend the following foundational components.

4.0.1 Conditional Use Permit Requirements for Nearby Jurisdictions Below is a concise comparison of Conditional Use Permit (CUP) frameworks across selected Coachella Valley agencies as well as other relevant jurisdictions.

City CUP Requirement Odor Control Specifics Enforcement Palm Springs Mandatory Operating plans, filtration,
inspections Permit suspension/inspection
Desert Hot
Springs Mandatory Detailed odor equipment in CUP, annual renewal Permits revoked if non-compliant Coachella Mandatory Time/place/manner review,
odor part of hearings Local discretion
Palm Desert CUP + regulatory
permit required Filtration implicitly required Standard CUP enforcement Grover Beach Mandatory
Uses County CUP standards,
detailed odor equipment with
annual recertification
Permit/business license suspension
Santa
Barbara Co. Mandatory
Detailed OAP with carbon
scrubber use requirements,
vapor phase / misting ban
Nasal ranger enforcement, penalties,
operational compliance required,
legal precedent for lawsuits
Performance-Based Standards
Rather than mandating specific odor control technologies, SCS recommends a technology and manufacturer agnostic approach where the City adopts a performance-based standard for odor control. This approach allows operators to select and propose systems best suited to their facility design and odor sources. The performance-based standard also provides flexibility for technological innovation as the odor control technology industry continues to evolve rapidly and new systems are tested for efficacy, introduced into the marketplace and system costs vary widely depending on the size and scope of the facility operations. This method also simplifies regulatory enforcement by focusing on measurable outcomes (e.g., verified odor complaints, odor sample testing following system introduction and improvements). Adopted standards should conform with considerations outlined in Section 5.2.

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Standardized Submittal Elements
A standardized submittal checklist has been provided in the appendix to assist in streamlining the permit review process and maintain consistency across applicants. The checklist includes substantial considerations for submittal review for any cannabis facility type. Key insights from OAP reviews include:
• Details on the facility and the supporting operations. • Vicinity and facility maps with proximal sensitive receptors and accurate distances and dimensions.
• Detailed specifications for all odor mitigation equipment, including manufacture make/model, quantity, flow capacities, media types, system configurations and control points.
• A narrative description of the site-specific odor mitigation strategy, explaining how the selected controls address potential odor sources under typical and worst-case conditions. • Maintenance schedules and media replacement intervals, with justification tied to manufacturer recommendations, specs or operational history. • Testing and sampling procedures, if applicable, ensuring system efficacy. • Engineering drawings or system schematics that depict the physical layout of odor control infrastructure within the facility, where odor controls are installed and how they integrate with ventilation systems.

Submittal Requirements
Ensuring technical credibility of the submitted odor abatement plans, the City should establish minimum qualifications for third-party consultants or engineers preparing the plans. This standard improves the quality and defensibility of submitted plans, reducing staff burden and ensuring fair expectations for applicants. Qualifications should include:
• Documented experience in designing or evaluating odor mitigation systems. • Certified Industrial Hygienist (CIH) or Professional Engineer (PE) licensure. • References demonstrating successful implementation or review of odor control system in cannabis or similar industries.

Review & Verification Protocols
SCS recommends the City adopt a formal review and verification process that includes an initial technical review to assess the completeness and adequacy of each OAP submission, including conformance with the checklist requirements and adherence to performance expectations. This process can be documented in internal review guidelines or codified as part of the permit ordinance or conditions of approval.

We also recommend field inspections and/or odor monitoring as needed to verify implementation and effectiveness. Having triggers for plan updates is also important as operational changes, technology upgrades, and/or documented odor complaints suggest underperformance, should also be in place. We recommend technical OAP update and review following any substantive improvements or changes to the facility including:
• Following odor control system modifications or changes in quantity, type, or operational adjustments to system.

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• Following facility improvements, adding or removing processes, site renovations, tenant improvements, or any other activity that alters the odor control system or odor generation at the facility.
• OAPs should be updated and resubmitted reflecting the system/facility changes and indicate that the system functionality continues to address on-site odor control.

Section 4.0 Summary and Recommendations
• We recommend the City adopt a permitting structure that places responsibility for demonstrating effective odor control directly on cannabis operators. • We recommend Conditional Use Permits (CUP) require formal Odor Abatement Plans (OAP) for all cannabis facilities, consistent with regional best practices. • We recommend the City adopt a performance-based odor control standard, rather than mandating specific technologies.
o Operators would be responsible for selecting and implementing odor control systems that meet measurable performance outcomes (e.g., verified odor reduction, complaint thresholds).
o This technology-agnostic approach provides flexibility for innovation and scalability across facility types and sizes.
• We recommend implementing standardized submittal requirements to promote consistency, efficiency, and defensibility in plan reviews. • We recommend the City establish minimum qualifications for third-party consultants preparing OAPs to maintain the integrity of technical evaluation. o We recommend requiring CIH or PE licensure and documented experience with odor mitigation in cannabis or similar industries.
• We recommend the City adopt a formal review and verification process for submitted OAPs.
o Initial technical reviews should assess plan completeness, adequacy, and conformance with City standards.
o We recommend incorporating field inspections and/or odor monitoring to verify proper system installation and initial baseline performance. This can be performed by a third party.
• We recommend establishing clear triggers for OAP updates to reflect operational or facility changes, including:
o Modifications to odor control systems (equipment quantity, type, or settings). o Facility expansions, process changes, tenant improvements, or activities that alter odor generation.
o Updated OAPs should demonstrate continued system effectiveness and alignment with performance-based standards.

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INSPECTION AND VERIFICATION PROTOCOLS
While there is no single molecule that represents “odor” and can be easily targeted or measured in real time, there are a range of identification and measurement tools to objectively identify odors.

Cannabis odor inspections in Cathedral City shall be governed by scientifically grounded procedures that include qualitative odor assessment, quantitative odor measurement, and source identification, using sample collection and dispersion modeling as necessary. These inspections serve as the basis for determining compliance with City regulations, issuing violations, and enforcing corrective actions.

All inspections shall be carried out by City personnel trained in odor verification techniques or qualified third-party assessors approved by the City.

Protocols and Continued Compliance
Inspection Protocols
Section 5.2 below expands on a host of options for monitoring and assessment methods related to odor. General audits and inspections should be done annually, or at a frequency determined by the City, at each facility to align all businesses to the same consistent performance standards, confirm all systems are operating properly, respond to changing conditions, and provide a paper trail of ongoing compliance. In short, compliance checks are used to confirm that operators and their employees are knowledgeable about the odor mitigation strategies they are employing. Appendix B contains an example Audit Form for items necessary to review during site visits. Items pertinent to audits, regardless of business type, include but are not limited to:
• Noting any observations of odors at the facilities property line or at adjacent properties; • Reviewing facility diagrams for completeness:
o Are odor control systems, exhaust points, negative pressure systems, etc labeled on the map/facility diagram?
o Is the map accurate?
• Inspecting each systems performance and identifying opportunities for maintenance such as clearing dust from intakes, replacing loaded filters based on manufacturer’s recommendations, or tightening fittings;
• Checking for leaks in the building envelope.

Demonstration of Compliance
While Audits verify that the systems in place are in operation, performance testing or third-party verifications assess operational effectiveness. Requirements for these depend on cases such as:
• Documentation of inconsistencies or repeat violations in multiple audits; • When discrepancies arise between visual inspections of system conditions and planned controls during an audit;
• After equipment modifications and upgrades, or facility layout changes; • Prior to or immediately after the commission of new equipment or systems.

The frequency of and requirements for internal audits and compliance checks should fall under the management of the facility. We recommend quarterly internal verifications for odor control and air filtration system performance, including required documentation of routine maintenance checklists and filter replacements. The schedule and methods for internal verifications should be included in the facilities OAP. Routine odor monitoring provides facilities with defensible documentation of performance and enables them to demonstrate a proactive approach to odor management and regulatory compliance.

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Enforcement Triggers and Subsequent Process
Regulations should not rely solely on complaints or triggers to elicit action, and odor audits or verifications should occur on a frequency defined by the City; however, verified complaints can drive action, and an example complaint verification, investigative, and corrective action process would look like this:

Stage 1 – Log Complaint Data (and build a Predictive Odor Window) • At a frequency defined by the City, complaint data will be reviewed to gather time-of-day and day-of-week patterns from odor complaints. These will be overlayed with historical wind patterns and weather conditions. This creates a Predictive Odor Window (POW). • With the POW defined, the City will conduct inspections in the POW. This allows the City to conduct targeted inspections as opposed to reactive enforcement, and provides objective verification.
• If staff observations match ongoing complaints during the POW, continue to Stage 2. o Residents and stakeholders generally expect a quick response, so public communications from the City regarding the non-reactive timeframe and benefits of this Predictive Program will be important.

Stage 2 – City Response
• City personnel or a City appointed representative will conduct in-field investigation(s) of odor surrounding the Facility in question using an Odor Assessment method listed in Table 3.

Observations must be documented in a standardized form noting the inspector’s name, location of observation, weather conditions, and time of observation. This method must be consistently utilized once chosen and written into the cannabis ordinance. The window of time during which the in-field investigation takes place must align with the POW’s specified timeframe.
o Based on the June 17, 2025 call with the City, direct olfactory observation is the preferred method of identifying odor and determining compliance with the “No Odor at the facility property line” requirement.
• In the field, investigations will be made downwind of the facility at the property line or 100ft downwind of the building edge, dependent on accessibility. o The detected odor must be characteristic to its distinctive operation. o If odor is NOT detected, the process of investigation for the facility in question, initiated by the complaints that created this specific POW is complete. o If odor IS detected, continue to Stage 3.

Stage 3 – Corrective Action
• The facility in question will be issued a Corrective Action Notice (CAN) by the City within three (3) business days of a failed inspection. The Operator shall submit a Plan of Action within seven (7) calendar days, detailing the problems identified, Corrective Actions to be taken, and establish a timeline for implementation. Corrective actions shall be implemented within three (3) weeks of the original CAN, unless otherwise approved by the City. o Should these deadlines not be met, a fine, as determined by the City, shall be imposed.

Cathedral City – Regulatory Review - Cannabis Odor Control www.scsengineers.com

o An example Plan of Action is included in Appendix B.
• Once the mitigation deadline is met, in-field investigations as listed in Stage 2 will be repeated.
o If odor is NOT detected, the process of investigation for the facility in question, initiated by the complaints that created this specific POW is complete. o If odor IS detected, repercussions as determined by the City will be implemented.

Continue to Stage 4.

Stage 4 – Third Party Mitigation
• The Facility in question will consult with, and retain as necessary, a third-party odor consultant at the operator’s expense, to mitigate the nuisance odors by a deadline implemented by the City. This could include, but is not limited to, implementing or revising an Odor Abatement Plan, installing approved Odor Control Technologies as listed in Table 2, conducting odor source identification to directly target and address the source, etc. Chemical surrogates used to measure odor in real time, as listed in Table 4, could also be implemented by the Facility in this Stage as a preventative measure or as a measure of defensibility.
o Qualifications for the third party must meet minimum levels of competence. In addition to understanding odor dynamics, examples of competencies may include, but are not limited to:
 Completion of an Odor School program
 Certification as an Industrial Hygienist (CIH)
 Licensure as a Professional Engineer (PE)
o Defensible methods in addressing odor source and receptor perception are listed in Section 5.2.1.
• Once the deadline is met, in-field investigations as listed in Stage 2 will be repeated. o If odor is NOT detected, the process of investigation for the facility in question is complete.
o If odor IS detected, harsher repercussions, as determined by the City, will be implemented. Stage 4 shall be repeated until odor is no longer detected, or until continued noncompliance results in revocation of the license.

Cathedral City – Regulatory Review - Cannabis Odor Control www.scsengineers.com

Section 5.1 Summary and Recommendations
• Recommended frequency for site Audits are annual
o Audit notes: As a reference point, carbon filters are typically replaced every 3 to 6 months in high load environments but can extend to roughly a year based on specific use. Prefilters are typically replaced monthly. We recommend spot checking scrubbers and referencing maintenance logs to verify. • Building a Predictive Odor Window (POW) and inspecting a facility in that window is recommended in addressing complaints. This is a targeted approach as opposed to reactive and will prevent the City from being first responders. • Screening complaints:
o The City will screen complaints, or contract a third-party complaint management firm, to track and analyze:
 Complainant name and contact
 Exact date and time of odor event
 Location
 Odor character
 Duration
 Strength (faint, moderate, strong)
 Meteorological data (if available)
• We recommend the inspector take precise notes. Observations should occur downwind of the Facility in question. If observed odors are upwind, odor could be attributed to other operations. The precise location is vital in collecting complaint information; the address alone is not sufficient.
• We recommend the inspector to have a handheld anemometer to detail wind conditions during inspections.
• We recommend inspectors come equipped with a filtered mask, to avoid “nose fatigue” or “nose blindness”. They should wear the mask in between observations and take necessary breaks.
• In areas with a dense concentration of cannabis operations where odor is detected at the property line, the burden should shift to the operator to demonstrate compliance (e.g. maintenance records, odor control data). We recommend operators have wind sensors onsite to provide supplementary data.
• We recommend incremental increases in fines should proper documentation not be submitted to the City or deadlines are not met.
• We recommend the enforcement language be changed to be more flexible, e.g. “No operator shall cause or allow the release of cannabis-related odors beyond the property line of their facility that are detectable and offensive to a reasonable person of normal sensitivity, as determined by the City.”
• We recommend the City schedule the follow-up inspection within 30 days after the Corrective Actions have been implemented.

Cathedral City – Regulatory Review - Cannabis Odor Control www.scsengineers.com

Odor Identification and Monitoring
The below sections are listed for informative purposes for the City, while responsibility to carry these out should fall under the facility and their chosen third-party consultants.

Odor Source Identification
To confirm the source of detected odors, SCS recommends that all facilities engaged in cultivation, manufacturing, or processing install and maintain an onsite Meteorological (MET) system capable of recording wind direction and wind speed. Retail and distribution facilities should be exempt from this requirement due to their significantly lower odor mitigation needs; however, if an inspection is failed, operators may be required to install and maintain an onsite MET system at the City’s discretion. MET sensors must be calibrated at least annually, and all collected data shall be archived and accessible for a minimum of two years.

Real-time and historical MET data in conjunction with operational logs and complaint timing will be used to assess source attribution. In areas with multiple cannabis operators, facility-specific odor logs and equipment performance records may be used to differentiate responsibility.

Below is a list of typical information compiled for identified odor sources:
• Location
o Coordinates
o Proximity to buildings/structures
• Release height
• Release dimensions
o Surface area/diameter
o Velocity or flowrate
o Temperature and pressure
o Release configuration details (rain cap, horizontal release, partial enclosure…) • Operating schedule (by hour)
o Continuous, hourly fluctuations, seasonal fluctuations, etc.

Sample Collection and Analysis
When field inspections do not produce conclusive results or are subject to dispute, the City may require air sample collection. Tedlar bags are typically recommended for collection due to their effectiveness in preserving volatile organic compounds and sulfur compounds associated with cannabis odor. Samples shall be analyzed using ASTM E679 and ASTM E544 by an accredited laboratory, or by using the European Standard EN 13725. For analysis via all methods, samples should be analyzed within 36-hours of collection for sample integrity.

Air samples shall be collected at the facility boundary and, where applicable, from ridge vent or effluent locations during periods of anticipated maximum odor generation. Sampling should be scheduled based on production cycles, meteorological forecasts, and historical complaint data to capture peak emission periods. All samples must be collected while the facility is operating under normal conditions and in accordance with standard operating procedures to present representative results.

During onsite sample collection, additional data that may be collected that can assist in the odor assessment are below:

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• Meteorological conditions during sample collection: wind direction, speed, atmospheric condition, precipitation
• Operating conditions during sample collection: what equipment is operating, operating throughputs, equipment condition (obvious issues)
• Ambient upwind and downwind samples for odor analysis • Measurements/analysis of potential odor surrogates, such as Total Reduced Sulfurs.

Odor Emission Rate
In cases of repeated violations or where corrective action plans are incomplete or disputed, the City may mandate source testing of odor emission rates.

The odor emission rate, source strength, is calculated for the identified odor sources by multiplying the odor concentration by the volumetric flow rate (in units of m3/s) of the release point. Volumetric flow rate for a point source (e.g., stack or vent) is:
• Calculated by the product of the air velocity in the stack/vent/duct and the cross-sectional area; or
• Obtained from equipment specifications, source testing reports, permit applications, or other documentation.

Volumetric flow rate for a non-point source (e.g., fugitive emissions) is estimated using engineering calculations, air velocity meters, and/or advanced measurement techniques such as a sampling hood (flux chamber).

Odor Dispersion Modeling
An atmospheric dispersion model is used to estimate off-site odor concentrations resulting from the source(s) identified from facility operations. The American Meteorological Society/Environmental Protection Agency Regulatory Model (AERMOD) is an often-used model by regulators, environmental consultants, and professionals for this type of modeling. Required input data for AERMOD includes:
• Odor source parameters (i.e., emission rate, dimensions, flowrate, temperature, pressure) • Odor source operating parameters (continuous, daily limits, seasonal limits, annual limits) • Building downwash parameters (building dimensions and heights) • Meteorological data (upper air and ground level – sources from National Weather Stations) • Terrain data (i.e., National Elevation Dataset terrain data files) • Receptors (locations the model will calculate odor concentration at – user specified) • Model options (specifics on dispersion options selected by user)

5.2.1.3.1 Model Results
AERMOD estimates the maximum odor concentration (D/T value) for the receptors (locations) included in the model. The model can be configured to output combined impacts from a facility as well as the odor impacts from individual onsite sources. The peak offsite odor concentration can be identified and then compared to an appropriate nuisance odor threshold for the region. For example, odors may be classified as a nuisance at or above 7 D/T. In addition, the modeling results can be processed into odor concentration contours that are overlaid onto aerial maps of the study region.

These contours help identify any offsite areas where estimated impacts exceeded the applicable nuisance odor threshold. If the predicted off-site impacts exceed the nuisance odor threshold selected, then additional modeling runs can be performed to identify the sources driving the results Cathedral City – Regulatory Review - Cannabis Odor Control www.scsengineers.com

as well as the amount of mitigation (i.e., reduction in odor emission rates) for predicted impacts to be below the nuisance odor threshold.

5.2.1.3.2 Model Limitations
A limitation and challenge when using air dispersion models to estimate odor impacts is the time and space resolution the model is based on (Nicola Pettarin, 2015). The smallest increment of time typical air dispersion models calculate results on is one hour, while it takes a few seconds for a person to inhale and perceive an odor. This is a large discrepancy between what the model will estimate and what a person may perceive. Furthermore, a modeled hourly average will not mimic a short-term increase in odors from a source, such as unloading a mature cannabis flower delivery over a 10-minute period. During the 10 minutes of unloading, there can be an increase in odors from the activity that will not be seen in the model results.

Odor Monitoring Options
Odors are a perception experienced when chemicals come into contact with odor receptors on olfactory nerves. This perception is quantified using an odor detection threshold defined as the theoretical minimum concentration that incites an olfactory response or sensation (defining 1 odor unit, or 1 OU), and varies by population based on the below factors. Whether an odor is perceived as a nuisance depends on those factors, and sets the framework for criteria that can be used to assess odor impacts in the field and supports consistent decision-making in enforcement • Odor quality: odor results stemming from a pure compound tend to have a higher threshold (less offensive) than a mixture of compounds.
• Odor frequency, timing, and duration: when and how an odor is perceived within a community affects the annoyance and offensiveness of the odor. • Population Sensitivity: individuals have a range of sensitivity to odors. This is affected by past experiences and previous exposures, as well as individual association with the odor. Some of the population may find certain odors pleasant, while other members of the population may find them offensive. This factor appears to be especially true relative to cannabis odor. • Background Level: background odors can affect the degree to which a specific source contributes to a cumulative impact.
• Public Expectation: the relative level of community tolerance to an odor. For example, farming communities may consider a background level of odor to not be offensive even at high concentrations while residents of other communities find the same odors offensive even at low concentrations.
• Source Characteristic: how the odors are emitted is an important factor. Controlling odors from a point source is significantly easier to control than odors from an area or diffusive source.

It’s important to note that the odor detection threshold (DT) is lower than the recognition threshold (RT). The recognition threshold is the point at which the panelist(s) recognize the character of the odor. In addition, the annoyance threshold is higher than the recognition threshold.

Odor perception varies among individuals and direct assessment of odor perception relies on human olfactometry for determination of odor impacts. Increasing the number of humans and observations helps to normalize variations in individual odor perceptions. Known methods of quantifying and measuring odor are limited; and each method is associated with a series of pros and cons related to use case, quantification, and cost. Methods of assessing odors vary between those that utilize human perception or chemical surrogates. This section will go into depth on each. Brief summary tables for each category are provided below.

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Qualitative Assessment
Qualitative odor assessments involve evaluation by trained personnel in response to public complaints or as part of scheduled inspections. These inspections rely on the perception of cannabis odor character at a facility property line or adjacent building/facility. An inspection may be triggered by verified odor complaints from separate individuals within a set period.

Complaints will be cross-referenced with meteorological (MET) data to verify alignment with wind direction and facility operations at the time of the reported incident. Inspections initiated from complaints will only proceed when the complaint’s timing and location are consistent with MET data and there are enough complaints to meet critical volume to develop a POW.

Inspectors must identify if cannabis odor is perceptible at the facility property line, provide a value on a scale from 1-5 on the odor intensity, describe the odor character using consistent terminology, record wind and atmospheric conditions, and confirm that the facility was operational at the time of the incident. Observations must be documented in writing and supplemented with photographs and site sketches where applicable.

Quantitative Assessment
Quantitative assessments may use calibrated field olfactometers or odor panels to measure odor concentration. This determination must be supported by sensory descriptors and MET data alignment with facility operations. Measurements must be taken under stable wind conditions of at least 1.5 miles per hour. All data, including odor character, D/T values, GPS locations, and meteorological readings, must be recorded.

Odor Assessment via Human Perception
A summary of the methods odor can be perceived/measured is provided in the table below with further details in the following sections.

Table 3 Summary of Odor Perception Methods Via Humans
Odor Perception
Method:

Measurement
Units:

Benefits: Limitations:

Direct
Observation
None, Scale of
odor
Perception (i.e.
1-5)
Inexpensive, Observations
can be made anywhere a
human can be present.

Objective, qualitative only,
significant potential for bias.

Field
Olfactometer
Dilutions to
Threshold
Ratio
Relatively inexpensive, field
deployable, somewhat
quantitative.

Limited quantitate value,
requires trained personnel,
subject to bias, olfactory
conditioning probable, does
not determine source of odor.

Odor Panel
(ASTM Method)
Dilutions to
Threshold
Ratio,
Intensity,
Character
Highly quantitative,
panelists are unbiased,
panelists do not know
source type or location,
Vetted American Society of
Testing and Measurements
Method (ASTM).

Repeatable and proven.

Logistically constraining as
odor panel needs to be
reserved in advance of
measurements, samples
should be analyzed soon
(within 30 hours) after
sampling. Observations are
conservative (higher) than
that of general population.

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Can be expensive if large # of
sampling points and/or times
are necessary.

Direct Observation
No methods currently are available that appropriately simulate or quantify complex odors. Thus, it is difficult to predict human responses to exposures of chemical mixtures. The human nose is, to this day, the most suitable ‘sensor’. There is currently no substitute for assessing odor perception of complex sources than direct human perception. Direct Observation, however, is highly subjective. An individual is subject to biases such as background odor, familiar odors, or simply being an individual with either a heightened or decreased sensitivity to smell, among other biases. Additionally, these observations are only qualitative and do not provide a quantitative measurement that is repeatable.

Field Olfactometers
Olfactometers, invented over a century ago, operate on the principle of diluting odors. The amount of dilution required to reduce an odor sample below detection represents the strength of an odor.

The Nasal Ranger® and Scentometer are specific types of olfactometers commonly used by regulators for field assessments. They are portable odor measuring device that combines odor detection with odor quantification. Odor quantification is determined by the Dilutions-to-Threshold ratio, or D/T. This ratio is a measure of the volume of carbon-filtered air needed to make a volume of odorous ambient air non-detectable. Users must breathe through the device at a flow rate of 16 – 20 liters per minute (LPM) when using the device. Users of the Field Olfactometers must be trained and certified via a specific training course provided by their respective manufacturers.

Field use examples include:

1. On-site monitoring—for monitoring of various on-site procedures and operations,

2. Random monitoring—for monitoring correlating with meteorological information and on-site activities,

3. Intensive odor surveying—for determining sources and operations that cause odor,

4. Citizen monitoring,

5. Complaint response

6. Permit compliance, and

7. Plume profiling.

While field olfactometers are portable and offer multiple field use examples, there are some biases inherent to this method that are not present in olfactometry performed through the use of an odor panel. Because field olfactometers are deployed and used in the field, the operator is subject to field conditions and has already biased himself, his nose, and olfactory senses with the ambient air on location. In many cases, the human nose can become accustomed to an odor after a period of exposure and become “nose-blind” to the odor(s) under evaluation. Thus, using the Nasal Ranger® or field Scentometer to determine in-field D/T can have a low bias on the results.

Cathedral City – Regulatory Review - Cannabis Odor Control www.scsengineers.com

Figure 2: Examples of Field Olfactometers (Nasal Ranger, Facial Mask, Box Scentometer) Odor Panel
Using an odor panel on the other hand, removes the field environment bias seen with usage of the Nasal Ranger®. This method uses a stationary olfactometer that operates on the same principle as the Nasal Ranger®. Olfactometers generally have four (4) to six (6) stations for human panelists.

Each station is equipped with two (2) to three (3) sniff ports. One (1) random sniff port produces a stream of diluted odorous sample air, while the other port(s) produce a stream of pure air. Ideally, stationary olfactometers are located in an odor-free room, where panelists are asked to determine which port contains the odorous air. The dilution at which at least half the panel correctly and confidently identifies the correct port determines the D/T measurement of that sample of air. This is an objective method developed to establish odor concentration using human assessors.

The major constraint to this method is logistics. Generally, panels need to be booked in advance, and they can only handle a certain quantity of odor samples due to both time and panelist fatigue.

Additionally, odor samples have a holding time of 36 hours, so samples must be shipped to the odor lab via overnight courier, which can be costly.

Odor Assessment via Chemical surrogate
A summary of methods to assess odor through chemical surrogates is provided in the table below with further details in the following sections.

Table 4 Summary of Odor Assessment Via Chemical Surrogate Analytical
Measurement
Measurement
Units:

Benefits: Limitations:

Time Averaged
Samples with
follow-up Analysis
via Analytical
Laboratory
Dependent on
Method
Many compounds can be
detected to ppb level
accuracy.

Costs are per sample and can
be expensive. The sample only
represents the time and
location the sample was
collected. Field labor
dependent and requires
sampling expertise. No single
analytical method will cover all
odor causing emissions.

Cathedral City – Regulatory Review - Cannabis Odor Control www.scsengineers.com

Analytical
Measurement
Measurement
Units:

Benefits: Limitations:

Total VOC
Detection w/
Photoionization
Detectors (PID)
Parts per billion Inexpensive analyzer
measures for total VOCs.

Fast response time and is
capable of real-time
measurements
Does not differentiate between
VOCs, Calibrated based on
single VOC that may be very
different from compounds of
interest. Responds to VOCs that
can exist in high background
concentrations. Many VOCs are
not significant contributors to
odors.

Field Deployable
GC w/ Various
Detectors
Parts per billion Accurately identifies and
quantifies concentrations of
multiple target compounds.

Can collect and measure
samples every 10 minutes
depending on the specific
compounds of interest. Can
be adapted to measure at
multiple sampling locations.

Limited detection to
compounds of similar retention
times under current
configuration. Calibration
standards are field-generated
or need to be created by
certified labs relative to the
compounds of interest. GC
system set up for terpene
analysis currently do not detect
any organosulfur compounds of
interest. The concentration of
measured VOCs relative to odor
concentration is not always
suitably correlated.

Electronic Noses
(electrochemical
sensors)
10-100 Parts
per billion
Measures multiple chemical
constituents that are known
to be odiferous
May not be able to detect all
the compounds emitted by
source known to be part of the
odor profile. Limited to specific
parameters and sensor types.

Total Reduced
Sulfurs (TRS)
Parts per billion Proven real-time surrogate
for odor concentration
Only works in high odor load
areas. Capability is severely
diminished outdoors.

Analytical Lab Analysis
There are a limited number of accepted standardized analytical methods performed by accredited laboratories for some compounds that are known to be odiferous. These methods include sample collection procedures, sample handling, as well as analytical methods specific to compounds or classes of compounds. Sulfonated compounds using ASTM D-5524 and certain Volatile Organic Compounds (VOCs) using EPA T0-15 are examples. With these methods, each sample can be tested for multiple compounds and down to a relatively low detection limit. This is important as many odiferous compounds have very low odor detection thresholds. It’s important that the sample collection and analytical method are compatible with the odor detection threshold of the target compound(s). However, each sample is only representative of a snapshot in time, and doesn’t show real-time or immediate results. Conducting the field sampling requires training, and each individual sample has an associated cost.

Cathedral City – Regulatory Review - Cannabis Odor Control www.scsengineers.com

Photoionization Detectors (PID)
PIDs are field measurement tools that detect VOCs. They produce real-time readings and are generally used during first responses for many use cases, such as detecting a potential leak in the system or qualitative assessment of the presence of VOCs. However, while they are fast responding and can detect multiple VOCs, they cannot speciate and differentiate the compounds detected from each other. This may be ineffective in cases where there are multiple background compounds present.

Portable Gas Chromatograph (GC)
Portable Gas Chromatographs (GC) can be deployed in the field to speciate VOCs. However, while this method can identify and quantify individual VOCs, there are limitations to this method. GCs can only quantify predetermined, thermally stable compounds. Compounds with similar retention times can also be measured which leads to co-elution and potential interferents. Additionally, the VOCs identified may or may not be contributors to the odor profile. This method may not be real-time, but readings can be generated in field, and samples can be collected and analyzed roughly every 10 minutes. This method provides a middle ground between real-time sampling and discrete grab samples.

Electronic Nose
The Electronic Nose (e-Nose), is a type of electrochemical device that uses sensors that generate signal patterns to characterize odors. These sensors detect and react to different molecules which create response patterns due to changes in electrical properties that are then interpreted and analyzed. Most e-Noses use chemical sensor arrays that react to volatile compounds on contact, and the adsorption of these compounds causes a physical change of the sensor, which is then translated by the electronic interface into a digital value. E-Noses have been used in evaluation of odors related to the food, health, drug, safety, crime, and the environmental and agricultural sectors. However, it should be noted that they do not measure odors directly and that this technology uses chemical surrogates to calculate an odor index. The value an e-Nose can provide is limited to the array of sensors installed and may not correlate well with cannabis emission sources.

Cathedral City – Regulatory Review - Cannabis Odor Control www.scsengineers.com

Section 5.2 Summary and Recommendations
• We recommend responsibility for odor source identification and monitoring fall to cannabis operators and their qualified third-party consultants, subject to City oversight. • We recommend facilities engaged in cultivation, manufacturing, or processing install and maintain onsite MET sensors to record wind direction and speed. • We recommend facilities maintain detailed records for identified odor sources. • We recommend the City reserve authority to require air sampling, emissions rate monitoring, or dispersion modeling where field inspections are inconclusive or disputed. • We recommend a tiered response system for verified odor events, with escalating actions based on severity, complaint volume, and facility history, aligned with Section 5.0 recommendations.

Cathedral City – Regulatory Review - Cannabis Odor Control www.scsengineers.com

BIBLIOGRAPHY
A. B. Malnic et al, Cell, 1999, 96, 713
American Industrial Hygiene Association, 2013. Odor Thresholds for Chemicals with Established Health Standards, Second Edition, Falls Church, Virginia: s.n.

Autelitano, F. a. G. F., 2018. Anatical assessment of asphalt odor patterns in hot mix asphalt production. Jornal of Cleaner Production, Volume 172, pp. 1212-1223.

Freemantle, M., 1999. Chemical & Engineering News. [En ligne] Available at: cen.acs.org
Grahn, K. G. P. A. T. L. A. H. T. S. J. a. P. W., 2021. Occupational exposure to particles and increased risk of developing chrominc obstructive pulmonary disease (COPD). A population-based cohort study in Stockholm, Sweden. Environmental Research 200: , p. Article 111739.

Hansen, E., 1991. Mortality of mastic asphalt workers. Scandinavian Journal of Work and Environmental Health 17, pp. 20-24.

IARC, 2013. Bitumens and Bitumen Emissions, and Some N- and S- Heterocyclic Polycyclic Aromatic Hydrocarbons. Volume 103. Lyon, France: s.n.

Jue Li, Y. Q. X. B. S. a. C. L., 2024. Emission Characeristics, Environmental Impacts and Health Rsisks of Volatile Organic Compounds from Asphalt Materials: A State-of-the-Art Review. Energy & Fuels .

Kargar-Shouroki, F. M. M. S. M. S. S. F. M., 2021. Genotoxic effect of exposure to polycyclinc aromatic hydrocarbons (PAHs) in asphalt workers. EXCLI Journal 20, pp. 686-697.

Lange, C. a. M. S.-G., 2005. Quantification of Potentially Odorous Volatile Organic Compounds from Asphalt Binders Using Head-Space Gas Chromatography. ASTM Journal of Testing and Evaluation, March, 33(2), pp. 101-109.

M. Edwards, J. H. R. H., 2020. Odour Management Guidance for Refineries, Brussels: CONCAWE.

NIOSH, 2024. NIOSH Pocket Guide to Chemical Hazards.. [En ligne].

OSHA, 2024. OSHA Occupational Chemical Database. [En ligne] Available at: https://www.osha.gov/chemicaldata/710
Petronaft, 2024. htttps:www.petronaftco.com/oxidized-bitumen. [En ligne].

Wikipedia, 2024. Heterocyclic Compound. [En ligne].

World Health Organization, 2004. Concise International Chemical Assessment Document 59. Aspahlt (Bitumen), Geneva: s.n.

Z. Zhou and L. B. Buck, Science, 2006, 311, 1477
Cathedral City – Regulatory Review - Cannabis Odor Control www.scsengineers.com Page A
Appendix A
What is Odor?
Cathedral City – Regulatory Review - Cannabis Odor Control www.scsengineers.com Appendix Page A-1
What is Odor?
Odor is a perception and is dependent not only on the relative chemistry and structure of odor molecules, but also on receptor factors such as sex, age, culture, social context, and personal experience. Odor perception is complex as responses to odors are inherently subjective and the nature and composition of odorants can vary greatly. In addition, different societies have varying levels of acceptance for odors in their communities.

Olfactory System
People can discriminate more than 10,000 odors, even though there are only about 400 odor receptors in the nose (Coker, 2013). An odor can generally be perceived if several criteria are met (Govind, 2023).
• There is an odor generating source present,
• The odorant molecule(s) is a volatile compound (VC),
• The odorant’s molecular weight is less than 300 Daltons, • The odorant’s vapor pressure is greater than 0.01 kilopascals (kPA) at 20 °C, and • The odor molecule has moderate-to-high hydrophobicity.

During the respiratory process, when odorous molecules enter the nasal canal, they reach the olfactory epithelium, near the top of each nostril. At this point, the molecules dissolve in the mucus layer covering the epithelium and contact olfactory sensory neurons (millions) which express the odor receptor(s) (~400) (Alila Medical Media, 2021). The combination of activated neurons and odor receptors send signals to the olfactory bulb, where the signal is deciphered and subsequently perceived by the brain as an odor perception. When you have a cold, your sense of smell is diminished because molecules have a harder time reaching the odor receptors. See Figure 1.

Studies on the interactions between
individual odor receptors and multiple
chemical odorants found that:
• An odor receptor can recognize many
odorant molecules, and
• An odorant molecule can bind to and
be detected by multiple odor
receptors.

Through the use of approximately 400
odor receptors in humans, the brain can
differentiate between a large number of
odorants simultaneously. Thus, although
there are only a few hundred active odor
receptors, humans can recognize over
10,000 different odors. This method is
referred to as the “Receptor Code”. The
receptor code is essentially the unique
pattern of activated receptors for a
specific odorant, and this pattern can shift
depending on concentration, leading to different odor perceptions.

Figure -1: Human Olfactometry System (Coker, 2013)
Cathedral City – Regulatory Review - Cannabis Odor Control www.scsengineers.com Appendix Page A-2
Chemical Concentration and Mixture Effects
Researchers have found that changes in odorant concentration alter its receptor code in the olfactory system. This explains why, for some chemicals, a substance smells different at different concentrations. As the concentration of an odorant increases, the set of olfactory receptors activated also changes, leading to a different perception of the smell, even for the same odorant molecule.

Additionally, research has shown that some neurons in the olfactory cortex only respond when two odorants are present and not when each component is present on its own, explaining why mixtures can have smells that are not simply the sum of the component molecules (Z. Zhou and L. B.

Buck, Science, 2006, 311, 1477).

Odor Assessment
The relative detectability of odor is a sensory property that refers to the theoretical minimum concentration that incites an olfactory response or sensation. This point is called the odor detection threshold, often referred to through the dilution to threshold ratio (D/T) and defines one odor unit (1 OU). Based on the available literature, the level at which odors are perceived to be a nuisance can range from 2 OU to 10 OU depending on the following variables or factors:
• Odor Quality: odor results stemming from a pure compound tend to have a higher threshold (less offensive) than a mixture of compounds.
• Odor Frequency, Timing, and Duration: when and how an odor is perceived within a community affects the annoyance and offensiveness of the odor. • Population Sensitivity: individuals have a range of sensitivity to odors. This is affected by past experiences and previous exposures as well as individual association with the odor. Some of the population may find certain odors pleasant, which can be found offensive to other members of the population. This factor appears to be especially true relative to cannabis odor.
• Background Level: background odors can affect the degree to which a specific source contributes to a cumulative impact. Due to the saturation density of cannabis cultivation in certain instances this is an important consideration.
• Public Expectation: the relative level of community tolerance to an odor. For example, farming communities may consider a background level of odor to not be offensive even at high concentrations while residents of other communities find the same odors offensive even at low concentrations.
• Source Characteristic: how the odors are emitted is an important factor. Controlling odors from a point source is significantly easier to control than odors from an area or diffusive source.

Odor Detection Threshold
The odor detection threshold (ODT) is the lowest concentration of an odorant that can be detected by a person. The concentration is established through testing conducted on human subjects in a laboratory setting and is commonly listed as the lowest concentration at which at least 50% of test subjects perceive an odor. The lower the detection threshold, the more potent the odor is. For example, hydrogen sulfide (characterized by a rotten egg odor) can be detected at a concentration as low as 0.0005 part per million by volume (ppmv) while carbon dioxide (vegetable, sulfide, medicinal odor) is not detected until a concentration over 39,000 ppmv.

Cathedral City – Regulatory Review - Cannabis Odor Control www.scsengineers.com Appendix Page A-3
Because sensitivity to odor is subjective and varies from person to person, detection thresholds established for compounds vary and for this reason are frequently listed as a range of concentrations.

Due to the logistical constraints of using certified odor panels, it is not feasible to use odor panel analysis for complaint response. This is because odor panels need to be reserved ahead of time.

Any ordinance that specifies an ambient odor threshold (D/T, DT, RT, "Odor Units", etc.) should also specify the method of measurement as the different measurement methods produce different results. In addition, the effect of background odor concentrations on these measurements needs to be considered, as do the meteorological conditions during an odor event.

Due to the factors above SCS recommends that a Nasal Ranger or similar device be used for compliance monitoring relative to odors. In addition, the following factors should be considered:
1) Assessments of a source’s contribution to downwind odors should include measurements of background and or upwind odor and the differential in the two measurements should be considered as the net increase in odor.
2) SCS recommends a 7 D/T increase as a benchmark for downwind odor impacts if using detection threshold (DT).
3) SCS recommends a 4 D/T increase as a benchmark for downwind odor impacts if using recognition threshold (RT).

Finally, the ordinance should specify the number of observations that need to be made by the inspector and the period from which the observations need to be made. SCS recommends the average of 3 observations collected 5 minutes apart. This will confirm persistent conditions while not implicating sources if only a fleeting odor is detected.

Odor Characterization
Concentration alone does not describe the entire human response to an odor. Various qualitative and quantitative parameters are used to illustrate human perception to odors. A summary of parameters that can be used to further describe odor is provided in Table 1.

Table A-1: Technical parameter definitions used for describing odors Parameter Description
Concentration Odor concentration is quantified by determining the amount of dilution required to bring the odorous air sample to a detection threshold.

Intensity Odor intensity refers to the perceived strength of the odor. A quantitative measurement of intensity requires comparison of the odor to a “standard,” typically n-butanol in odor-free air. The intensity is expressed in terms of micrograms per cubic meter of n-butanol and is related to concentration through a power function.

A qualitative scale can also be used to describe intensity with zero being not perceptible to 6 being extremely strong.

Character Odor character describes what the substance smells like.

Examples of odor character include fishy, hay, nutty, oily, creosote, turpentine, rancid, sewer, sweet, ammonia, skunky, pine, wet grass, burnt hair, etc.

Hedonic Tone
(Offensiveness)
Hedonic tone is a subjective judgment on the relative pleasantness or unpleasantness of an odor.

Hedonic tone can be assessed on a graded scale from -4 (extremely unpleasant) to +4 (extremely pleasant) and 0 being neutral (neither pleasant or unpleasant) Cathedral City – Regulatory Review - Cannabis Odor Control www.scsengineers.com Appendix Page A-4
Cannabis Specific Odor Drivers and Variables
The understanding of the primary cause of the odor, particularly the disagreeable "skunky" odor emitted from cannabis cultivation, and the methods to mitigate it, are rapidly evolving. Just a few years ago, it was a common perception that the main culprit relative to odors from cannabis operations were terpenes. We now know that although terpenes are part of the odor profile, they are not the cause of the unpleasant “skunky” odor character often experienced downwind from cannabis operations. Terpenes are not the main driver of odor concentration downwind from cannabis facilities.

There is interest by several entities to establish an odor detection threshold relative to cannabis odor emission. The idea is to have a molecule or class of molecules, operate as a surrogate for expected odor concentration and thus be used to determine a threshold for which objectionable odors are likely to be perceived by humans. Several factors complicate this consideration:
1) Cannabis, like most plants, has the potential to emit hundreds of different chemicals. Each at various rates, at widely divergent odor detection thresholds, and dependent on several external variables;
2) Emission rates are not constant throughout the cannabis plant life cycle or within the plant’s diurnal cycle;
3) Emission rates are influenced by temperature, exposure to light radiation, degree of agitation, and plant stresses, among other external factors. 4) The ratios of compounds emitted by cannabis are not constant through the plant’s life cycle and the times of highest emission of certain compounds can be decoupled from the emission of other types of compounds.
5) Relative strains of cannabis have different chemical ratios and thus varying odor profiles.

Identifications of Odorous Compounds Emitted by Cannabis When SCS began working with cannabis growers, we were already well-versed in odor investigations relative to landfills, recycling centers, compost facilities, and water treatment plants. SCS was familiar with identifying a facility’s “odor footprint” through the use of ASTM-defined olfactory assessment using odor panels in combination with flux measurements from the sources at these facilities. In addition, the main culprit for objectionable offsite odors is almost always Hydrogen Sulfide (H2S) for these types of facilities and sources. The nature and understanding of these sources have been studied for decades. There is ample understanding of how odor emissions are generated and presently there are significantly researched methods to mitigate odor from these types of sources and facilities, which are more straightforward than for cannabis cultivation.

Initial Tests of Cannabis Emissions
Most analytical labs in the United States are set up to perform standardized test methods for known criteria pollutants or hazardous air pollutants (HAPs). In addition, the common public understanding was that the main source of odors was associated with the terpenoid class of compounds. There was also interest in determining whether cannabis emissions result in concentrations of HAPs that could be a potential health concern. Therefore, initially, SCS focused on Volatile Organic Compounds (VOCs) and terpenoids using standardized methods.

SCS utilized EPA Method TO-15 to assess the concentrations of VOCs that are also considered Hazardous Air Pollutants. SCS also requested tentative identification of a large list of other compounds for which the laboratory doesn’t carry standards but can be identified through chromatography and detection. SCS used non-standardized methods developed by the Desert Cathedral City – Regulatory Review - Cannabis Odor Control www.scsengineers.com Appendix Page A-5
Research Institute (DRI) to identify and quantify concentrations of a large library of terpenoids. Tests were performed in all aspects of cannabis operations including greenhouses, processing areas, drying rooms, and nurseries.

All of the tests showed that concentrations of VOCs and terpenoids were either not detectable or significantly below published health standards regardless of the location of the samples. In addition, the tests identified three terpenes that were present in almost every sample collected relative to a cannabis source. These terpenes were identified as Myrcene, Pinene, and Limonene. Caryophylene and Linalool were also detected in most samples. Tests indicated that emissions from the drying and curing phases of cannabis production were significantly higher than during the cultivation stage.

However, there were significant limitations to these tests:

1. The tests provided data that represented only the period and location from which the samples were collected.

2. The odor character of the measured terpenes does not represent the objectionable “skunky” character attributed to odor issues.

3. The tests were limited to Volatile Organic Carbons and terpenes. Other classes of compounds were not measured.

Identification of Volatile Sulfonated Compound (VSC) Emissions In SCS’s early investigations of cannabis emissions, we speculated that a sulfonated compound or a class of sulfonated compounds was the likely cause of the “skunky” character observed in the vicinity of cannabis operations. To test this theory, SCS performed an experiment.

The experiment entailed the collection of a ½ ounce of wet mature flower from 8 different strains of cannabis collected from multiple farms. SCS fabricated a blender/food processor with a bulkhead fitting at the top for the collection of a headspace sample. SCS then chopped/mixed each flower in the blender individually for 30 seconds. Immediately following the blending, SCS collected a headspace sample from above the blended cannabis. Immediately following sample collection, SCS delivered the samples to Atmospheric Analysis & Consulting, Inc. for analysis via ASTM-D5504. This method analyzes 21 different sulfonated compounds as well as Total Reduced Sulfurs (TRS). The difference between the sum of the detected sulfonated compounds and the TRS indicates the presence of an unidentified sulfur compound. The results of this test confirmed the hypothesis that VSCs were present for multiple strains. Three specific VSCs were identified, Carbonyl Sulfide, Dimethyl Sulfide, and Methyl Mercaptan. In addition, total reduced sulfur was detected in 6 of the 8 strains. The strains that were identified with the largest concentrations of total reduced sulfur were also confirmed to be the “skunkiest” strains based on the observations of cultivators.

Since this time, studies from other cannabis researchers have confirmed the presence of additional VSCs as potential sources of malodors from cannabis. To date, the following VSCs have been identified along with their relative scent character:

Cathedral City – Regulatory Review - Cannabis Odor Control www.scsengineers.com Appendix Page A-6
VSC Odor Character
• Dimethyl Sulfide: Sulfurous, cabbage
• Carbonyl Sulfide: Sulfurous, cabbage
• Methyl Mercaptan: Rotten cabbage
• 3-Methylthiophene: Fatty, wine-like
• 3-Methyl-2-butene-1-thiol: Intense, sulfurous, skunk-like • 3-methyl-1-(methylthio)-2-butene: Intense, sulfurous, savory • 3-methyl-2-butenyl acetothioate: Intense, sulfurous, skunk-like • bis(3-methyl-2-butenyl) sulfide: Mild, Onion and/or Garlic • bis(3-methyl-2-butenyl) disulfide: Mild, Onion and/or Garlic Cathedral City – Regulatory Review - Cannabis Odor Control www.scsengineers.com Page B
Appendix B
Example Forms
Facility Name & Location
Primary Odor Contact at Facility
Date / Time Complaint Receieved
Complaintant Information
Name
Contact Number
Email
Location of Odor Detected
Odor Type
Strength of Odor (1-10 Scale | 1 = no smell, 10 = overwhelming odor) Odor Direction (What direction was the odor observed to be coming from) Was weather unusual during odor detection event?
Odor character description
Site Conditions & Specifics Related to Odor Complaint
Wind Direction at time (Use MET Data)
Barometric Pressure
Action Taken
Action Taken (Consult Tiered Response)
NOTES:

Person Conducting the Inspection:

Date of Inspection:

Time of Observation :

Wind Direction (at the surveyor's location): N; NE; E; SE; S; SW; W; NW Barometric Pressure:

Measured in HG as recorded at the onsite weather station Intesity:
(S
‐
Strong; M
‐
Medium; Sl
‐
Slight)
Odor Complaint Response Form
Online Odor Complaint Form
Submitting Your Complaint
COMPANY provides several ways of submitting an odor complaint in the community. Feel free to use any of the listed complaint system methods to provide us your submission.

Thank you and we look forward to hearing from you.
 Web Form: complete and submit the interactive form on this page  Call:
 Text:
 Email:

Disclaimer: Information given through our complaint management system will be used solely by COMPANY. Your name and address is secured and no information will be given or sold to any third party.

Title
User Information
First Name
Last Name
Contact
Home Phone
Address
Cell Phone
Apt/Suite #
City
State
Zipcode
Remember my details on this computer for next time
(Not recommended if on a public or shared device)
Contact Preferences
I would like to speak with someone as soon as possible
I am happy to discuss this complaint should there be questions I would like a copy of this complaint sent to my email
Please do not contact me regarding this complaint
Save and Enter Odor Details 
Odor Details
We kindly ask that you provide as much information as possible. Details will help us review and process your submission.

Date
Time
Odor Detection Location
Where did you notice the odor?
Please identity the approximate location where you noticed the odor. (NOT where you think it is coming from)
Click on the map to drop a pin.

This will populate the LAT and LON automatically.

Online Odor Complaint Form
Use my address from the previous user information section Save and Enter Odor Details 
Odor Intensity
Very Faint
Faint
Distinct
Strong
Very Strong
Addition Comment
Please add any additional comments pertaining to your concerns. (Ex. Smells like a sunk or sewage. Smell lasted for several hours.) Odor Description
Ammonia
Burn/Smoke
Sewer/Sewage-like
Chemical/Solvent
Earthy/Moldy/Musty
Fishy
Manure
Decaying Grass
Rotten Egg
Turpentine
Woody
Other – See Notes
(enter notes)
(enter notes)
Save and Submit Odor Complaint 
Online Odor Complaint Form
Cultivation Facility Audit Checklist

INSPECTION ITEM Y N NA NOTES

1. Direct Observation
a. At Property Line ☐ ☐ Intensity:
b. Adjacent to facility structure ☐ ☐ ☐ Intensity:

2. State and local cultivation license
valid ☐ ☐

3. Odor Management Plan (OMP)
a. OMP date:
b. Located onsite ☐ ☐ ☐
c. Up to date ☐ ☐ ☐
d. Employee training record for
odor mitigation procedures
reviewed
☐ ☐ ☐

4. Facility diagram reviewed ☐ ☐ ☐
a. Odor control system located
on map
☐ ☐ ☐
b. Exhaust points located on
map
☐ ☐ ☐
c. Negative pressure system
labeled on map ☐ ☐ ☐
d. ___________ located on map ☐ ☐ ☐

5. Approved odor control system ☐ ☐ ☐ Make/Model:
a. Installed and operational ☐ ☐ ☐
b. Routine inspection
documented (+ take photos) ☐ ☐ ☐ Inspection frequency:
c. Filters clean ☐ ☐ ☐ Replacement frequency:

6. Air filtration units
a. Operational ☐ ☐ ☐
b. Labeled on facility diagram ☐ ☐ ☐
c. Maintenance log reviewed ☐ ☐ ☐ Last maintenance date:
d. Filters clean ☐ ☐ ☐ Replacement frequency:

7. Ventilation system
a. Operational ☐ ☐ ☐
b. Labeled on facility diagram ☐ ☐ ☐
c. Visible signs of buildup in
ducts or on vents ☐ ☐ ☐
d. Integrated with odor control
system ☐ ☐ ☐
e. Diagrams reviewed ☐ ☐ ☐
f. Maintenance log reviewed ☐ ☐ ☐ Last maintenance date:

8. Negative pressure system ☐ ☐ ☐
a. Operational ☐ ☐ ☐

INSPECTION ITEM Y N NA NOTES
b. Documented on facility
diagram ☐ ☐ ☐

9. Cultivation areas ☐ ☐ ☐
a. Enclosed ☐ ☐ ☐
b. Properly sealed ☐ ☐ ☐
c. Floor is clean; product is not
tracked everywhere ☐ ☐ ☐

10. Waste areas ☐ ☐ ☐
a. Enclosed ☐ ☐ ☐
b. Properly sealed ☐ ☐ ☐
c. Cannabis odors observed ☐ ☐ ☐

11. Facility operated odor complaint
management system
a. Available and operational ☐ ☐ ☐
b. Documented responses
accessible ☐ ☐ ☐ Review frequency:

12. Building envelope
a. Doors close automatically ☐ ☐ ☐
b. Operable windows in odorprone areas closed ☐ ☐ ☐
c. Air leaks and sources visible ☐ ☐ ☐
d. Loading/Unloading areas
enclosed ☐ ☐ ☐
Inspection Notes:
6d – clean filters are not loaded with a layer of dust or other materials. Dust or other materials may be on the filter but the filter itself is visible through the loading. Filters should be spot checked at easily accessible locations. Inquire about the process of how operators change filters.

Distribution Facility Audit Checklist

INSPECTION ITEM Y N NA NOTES

1. Direct Observation
a. At Property Line or adjacent
to facility ☐ ☐ Intensity:
b. Office space – Odors observed ☐ ☐ ☐ Intensity:

2. State and local cultivation license
valid ☐ ☐

3. Odor Management Plan (OMP)
a. OMP date:
b. Located onsite ☐ ☐ ☐
c. Up to date ☐ ☐ ☐
d. Employee training record for
odor mitigation procedures
reviewed
☐ ☐ ☐

4. Facility diagram reviewed ☐ ☐ ☐
a. Odor control system located
on map
☐ ☐ ☐
b. Exhaust points located on
map
☐ ☐ ☐
c. Negative pressure system
labeled on map ☐ ☐ ☐
d. Click or tap here to enter
text. located on map ☐ ☐ ☐

5. Approved odor control system ☐ ☐ ☐ Make/Model:
a. Installed and operational ☐ ☐ ☐
b. Routine inspection
documented (+ take photos) ☐ ☐ ☐ Inspection frequency:
c. Filters clean ☐ ☐ ☐ Replacement frequency:

6. Waste areas ☐ ☐ ☐
a. Enclosed ☐ ☐ ☐
b. Properly sealed ☐ ☐ ☐
c. Cannabis odors observed ☐ ☐ ☐

7. Facility operated odor complaint
management system
a. Available and operational ☐ ☐ ☐
b. Documented responses
accessible ☐ ☐ ☐ Review frequency:

8. Building envelope
a. Doors close automatically ☐ ☐ ☐
b. Operable windows in odorprone areas closed ☐ ☐ ☐
c. Air leaks and sources visible ☐ ☐ ☐
d. Loading/Unloading areas
enclosed ☐ ☐ ☐
Manufacturing Facility Audit Checklist

INSPECTION ITEM Y N NA NOTES

1. Direct Observation
a. At Property Line or adjacent
to facility ☐ ☐ Intensity:
b. Office space – Odors observed ☐ ☐ ☐ Intensity:

2. State and local cultivation license
valid ☐ ☐

3. Odor Management Plan (OMP)
a. OMP date:
b. Located onsite ☐ ☐ ☐
c. Up to date ☐ ☐ ☐
d. Employee training record for
odor mitigation procedures
reviewed
☐ ☐ ☐

4. Facility diagram reviewed ☐ ☐ ☐
a. Odor control system located
on map
☐ ☐ ☐
b. Exhaust points located on
map
☐ ☐ ☐
c. Negative pressure system
labeled on map ☐ ☐ ☐
d. ___________ located on map ☐ ☐ ☐

5. Cannabis Processing Onsite ☐ ☐ ☐
a. Flower Cannabis Processing ☐ ☐ ☐
b. Extract processing ☐ ☐ ☐

6. Approved odor control system ☐ ☐ ☐ Make/Model:
a. Installed and operational ☐ ☐ ☐
b. Routine inspection
documented (+ take photos) ☐ ☐ ☐ Inspection frequency:
c. Filters clean ☐ ☐ ☐ Replacement frequency:

7. Air filtration units
a. Operational ☐ ☐ ☐
b. Labeled on facility diagram ☐ ☐ ☐
c. Maintenance log reviewed ☐ ☐ ☐ Last maintenance date:
d. Filters clean ☐ ☐ ☐ Replacement frequency:

8. Waste areas ☐ ☐ ☐
a. Enclosed ☐ ☐ ☐
b. Properly sealed ☐ ☐ ☐
c. Cannabis odors observed ☐ ☐ ☐

9. Facility operated odor complaint
management system
a. Available and operational ☐ ☐ ☐

INSPECTION ITEM Y N NA NOTES
b. Documented responses
accessible ☐ ☐ ☐ Review frequency:

10. Building envelope
a. Doors close automatically ☐ ☐ ☐
b. Operable windows in odorprone areas closed ☐ ☐ ☐
c. Air leaks and sources visible ☐ ☐ ☐
d. Loading/Unloading areas
enclosed ☐ ☐ ☐

11. Storage area ☐ ☐ ☐
a. Product is stored in odor-proof
packaging ☐ ☐ ☐
b. Packages ready to ship – Odors
observed ☐ ☐ ☐
Consumption Lounge Audit Checklist

INSPECTION ITEM Y N NA NOTES

1. Direct Observation
a. At Property Line or adjacent
to facility ☐ ☐ Intensity:
b. Office space – Odors observed ☐ ☐ ☐ Intensity:

2. State & local cultivation license
valid ☐ ☐

3. Odor Management Plan (OMP)
a. OMP date:
b. Located onsite ☐ ☐ ☐
c. Up to date ☐ ☐ ☐
d. Employee training record for
odor mitigation procedures
reviewed
☐ ☐ ☐

4. Facility diagram reviewed ☐ ☐ ☐
a. Odor control system located
on map
☐ ☐ ☐
b. Exhaust points located on
map
☐ ☐ ☐
c. Negative pressure system
labeled on map ☐ ☐ ☐
d. ___________ located on map ☐ ☐ ☐

5. Approved odor control system ☐ ☐ ☐ Make/Model:
a. Installed and operational ☐ ☐ ☐
b. Routine inspection
documented (+ take photos) ☐ ☐ ☐ Inspection frequency:
c. Filters clean ☐ ☐ ☐ Replacement frequency:

6. Air filtration units
a. Operational ☐ ☐ ☐
b. Labeled on facility diagram ☐ ☐ ☐
c. Maintenance log reviewed ☐ ☐ ☐ Last maintenance date:
d. Filters clean ☐ ☐ ☐ Replacement frequency:

7. Ventilation system
a. Operational ☐ ☐ ☐
b. Labeled on facility diagram ☐ ☐ ☐
c. Visible signs of buildup in
ducts or on vents ☐ ☐ ☐
d. Integrated with odor control
system ☐ ☐ ☐
e. Diagrams reviewed ☐ ☐ ☐
f. Maintenance log reviewed ☐ ☐ ☐ Last maintenance date:

8. Negative pressure system ☐ ☐ ☐
a. Operational ☒
☐ ☐

INSPECTION ITEM Y N NA NOTES
b. Documented on facility
diagram/plans ☐ ☐ ☐

9. Waste areas ☐ ☐ ☐
a. Enclosed ☐ ☐ ☐
b. Properly sealed ☐ ☐ ☐
c. Cannabis odors observed ☐ ☐ ☐

10. Facility operated odor complaint
management system
a. Available and operational ☐ ☐ ☐
b. Documented responses
accessible ☐ ☐ ☐ Review frequency:

11. Building envelope
a. Doors close automatically ☐ ☐ ☐
b. Operable windows in odorprone areas closed ☐ ☐ ☐
c. Air leaks and sources visible ☐ ☐ ☐
d. Loading/Unloading areas
enclosed ☐ ☐ ☐

12. Storage area ☐ ☐ ☐
a. Product is stored in odor-proof
packaging ☐ ☐ ☐
b. Receiving area –Odors
observed ☐ ☐ ☐
Retail Facility Audit Checklist

INSPECTION ITEM Y N NA NOTES

1. Direct Observation
a. At Property Line or adjacent
to facility ☐ ☐ Intensity:
b. Indoor – Odors observed ☐ ☐ Intensity:
c. Office space – Odors observed

2. State and local cultivation license
valid ☐ ☐

3. Odor Management Plan (OMP)
a. OMP date:
b. Located onsite ☐ ☐ ☐
c. Up to date ☐ ☐ ☐
d. Employee training record for
odor mitigation procedures
reviewed
☐ ☐ ☐

4. Facility diagram reviewed ☐ ☐ ☐
a. Odor control system located
on map
☐ ☐ ☐
b. Exhaust points located on
map
☐ ☐ ☐
c. Negative pressure system
labeled on map ☐ ☐ ☐
d. ___________ located on map ☐ ☐ ☐

5. Air filtration units
a. Operational ☐ ☐ ☐
b. Labeled on facility diagram ☐ ☐ ☐
c. Maintenance log reviewed ☐ ☐ ☐ Last maintenance date:
d. Filters clean ☐ ☐ ☐ Replacement frequency:

6. Storage area ☐ ☐ ☐
a. Receiving area –Odors
observed ☐ ☐ ☐
b. Displays are filtered and
vented ☐ ☐ ☐

CITY OF CATHEDRAL CITY

RESPONSE TO CORRECTIVE ACTION NOTICE

PLAN OF ACTION
Company Contact
Address Cell

CORRECTIVE ACTION NOTIFICATION INFORMATION
Date of Inspection
Date of CAN By Whom
Plan of Action Due Date By Whom
Mitigation Due Date By Whom
Equipment and
Parameters
Breakdown
Description
Breakdown
Cause
Corrective
measures taken
to avoid future
occurrences.

Cathedral City – Regulatory Review - Cannabis Odor Control www.scsengineers.com Page C
Appendix C
Communication and Public Outreach
Cathedral City – Regulatory Review - Cannabis Odor Control www.scsengineers.com Appendix Page C-1
Communication and Public Outreach
It is important to realize that a community relations program will not solve your odor issues. But be assured that you will not resolve them successfully without a community outreach program. Having good lines of communication with your neighbors will greatly enhance your success to isolate any causes of odor impacts and guide the design to ultimately control impacts. Community outreach serves not only to educate the public about your facility, but it must establish a partnership between the facility operators and members of the public to work together to resolve issues. An antagonistic relationship will not help find reasonable and effective solutions.

The facility relationship with the community may not be limited to just odors issues. It may require expansion to collectively address a broad spectrum of potential environmental related neighbor concerns such as, but not limited to, traffic, noise, dust, and other environmental topics. When such a community relations program is enacted, the public will sense that they are involved with the entire operation and will help to foster public participation in the solution of any issues.

Understanding Community Concerns
When a person encounters an odor, particularly an offensive odor, their initial and primary concern is that the exposure to whatever is causing the odor will make them sick. This perception is evident not only for short term exposure (on the scale of minutes) but also for longer term exposures (days and months). In addition to health issues, people believe that when odor impacts occur, their property values will suffer. These concerns can drive community outrage and as outrage grows the sphere of influence of the odor impacts expand. Good communication with the public can reduce and even quell the outrage and enable the facility to reasonably deal with facts and not rumor or speculation.

When the public senses an offensive odor, they need to be able to voice their concern and have their questions resolved as quickly and honestly as possible. When people feel they have no recourse or means to resolve an issue, outrage and irrational thinking takes hold. It can be very difficult to gain the trust of the community when sentiments rise to this level or they have been misinformed. A good public relations program will provide easy pathways for the facility to respond to community issues as they occur. The bottom-line is that people need to be heard and taken seriously.

It is not uncommon for people to blame a facility for odors when that facility is not causing the odors.

People respond to impacts with what they see and sense and often do not rely on facts (for example is the wind blowing in a direction that would connect your facility with the person complaining?).

Alternatively, if real-time accurate information is conveyed from the community to the facility about detected odors, then effective and meaningful solutions can be tailored to mitigate impacts. Finally, the public wants to know that their welfare is being considered and prioritized in the operation of the facility.

Key Elements of Community Action Plan
Goal of your Community Outreach
The goal of a community outreach program is to establish a partnership with neighbors to the extent that you will work together to resolve problems. This involves building trust between the cannabis operator and the community. If this trust is lost, the facility is vulnerable to unreasonable and expensive mitigation imposed by regulatory authorities that are leveraged by a community that is not with the cannabis operator.

Cathedral City – Regulatory Review - Cannabis Odor Control www.scsengineers.com Appendix Page C-2
Community outreach must entail the conveyance of regulatory compliance, open dialog of measured data and observations, meaningful and open discussion of problems, and review of tailored solutions of which the community feels that they were a significant contributor. A public relations program needs to make the community feel that they are nothing less than a valued partner in facility operation and compliance.

Engaging with Community
Connecting with the community needs to take on a comprehensive outreach effort that can reach all levels of the community. There is no common or primary way that people communicate and gain information, so it is encumbered upon the facility to reach out in a variety of ways. This includes, but not limited to, the following:
• Having a designated odor complaint point-of-contact at each cannabis facility, who is trained on understanding and observing odor events, able to receive and log complaints, as well as be knowledgeable on the facility’s odor control system, how it’s maintained, ensuring operationality conforming to the manufacturers recommendations, where system improvements are logged, and routinely evaluated. Maintenance logs should be stored onsite for at least 5 years and readily available for trend analysis and historical inquiry. • In person Town hall meetings and presentations – the more personal interaction the better the chances of building a relationship.
• Zoom or Teams meetings that people can attend via computer link • Focus group meetings with small numbers of people – perhaps people from individual block neighborhoods or logical segments or subsets of the overall community. • General Information and Policy meetings.
• Educational Seminars – each on specific topics concerning odors – teach people on how to evaluate odors.
• Summary status letters and flyers sent to the community backed up on social media. • Light social events within the community sponsored by the facility – get people together.

Conveyance of Regulatory Compliance
Compliance with regulatory conditions is very important. The facility operators need to convey to the community a vision of compliance. This needs to be done as simply as possible so the public understands what compliance means, including what information is used to assess compliance. It is important to share this data with the public in a way that is understandable and visual. If possible, illustrate how the community has helped in attaining compliance with regulatory issues.

Cathedral City – Regulatory Review - Cannabis Odor Control www.scsengineers.com Page D
Appendix D
Cathedral City Council Staff Report: Cannabis Moratorium Update
Staff Report
City Council
Item No. 1.A
Meeting Date: April 23, 2025
From: Andrew Firestine, AICP, Director of Community and Economic Development
Title: Cannabis Moratorium Update
RECOMMENDATION:

This item is for discussion purposes to serve as an update on the cannabis moratorium. No action is requested.

BACKGROUND:

On February 26, 2025, the City Council extended the cannabis moratorium by 10 months and 15 days. Through the discussion, the City Council requested routine updates as staff conducts additional research and initiates updates to the City’s cannabis regulations and processes. The prior report focused on an evaluation of the City’s zoning, locational requirements, definitions, standards, and enforcement provisions, fines, and penalties while building out an odor control plan to implement the required conditions of approval. This report provides a synopsis of cannabis research conducted in other cities and counties and efforts to engage consultant support to set standards and to support the development of an odor control permitting process. It also provides updates on consultant support to the city specifically on C4 Industry and an odor control reporting and monitoring pilot program.

DISCUSSION:

Staff has commenced research in these areas, first by identifying all the California cities and counties that allow for cannabis cultivation in some manner, a list of 84 cities and counties, and conducted an initial review of the cannabis zoning regulations, licensing, and enforcement provisions for each of these cities and counties. This initial review was narrowed down to a smaller list of 15 cities and 3 counties that potentially offer insight into one or more of the areas of focus. A review of these city and county regulations, with an emphasis on zoning and enforcement, is summarized in the sections below with additional text contained in the attachments
Staff also initiated a records request through the Department of Cannabis Control (DCC) for the purpose of understanding how many large indoor cannabis cultivation facilities are licensed in the State of California. The DCC defines large indoor cannabis cultivation as those with more than 22,000 square feet of total canopy. For comparison, C4 Industry, the existing large cannabis cultivation facility near Date Palm Drive and Ramon Road has a gross floor area of 326,000 square feet and each of its 9 bays has a canopy area of 21,504 square feet together with an 8,760 square foot mother room, totaling over 200,000 square feet of total canopy area. While the DCC began accepting applications for large indoor cultivation licenses in 2020, there are only 6 other large indoor cultivation facilities licensed by the DCC, all of which are located in Richmond and Oakland. None of these are a good comparison to C4 Industry – most are substantially smaller in size and are older warehouses in industrial areas converted to cannabis cultivation.

The initial research of other city and county regulations, together with the additional information from the DCC, reveals that while there are some models for odor control permit processes and stronger enforcement, no city or county is at the forefront of cannabis regulation. No city or county has adopted objective cannabis odor standards and most rely on reactive and subjective odor measurements for enforcement. These preliminary findings raise the importance of the city’s existing condition of approval on cannabis conditional use permits requiring odor mitigation.

As was identified in previous staff reports, there is no separate plan or document and there are no standards or minimum requirements to demonstrate how the City’s odor mitigation requirements are to be met. Other cities and counties have established odor mitigation requirements through an odor control plan and permitting process, which is captured in the summary below. To ensure the City is setting the right standards, including the evaluation of technologies and the establishment of odor control requirements, the development of content and submittal requirements for an odor control plan, and the preparation of inspection checklists, consultant support is needed. To date, staff has met and engaged with five companies with significant experience in cannabis odor control and monitoring and has prepared a scope of work specific to the City’s needs. This scope of work was issued for informal bid on April 14 with bids requested by April 28. A summary of the expected scope of work is provided below.

Through the process of identifying prospective consultants to engage with on an update of the City’s cannabis regulations, staff identified a nationally recognized expert on soil vapor sampling, soil vapor analysis, and vapor intrusion for environmental and exploration applications who has extended his work into the cannabis industry through the monitoring of cannabis odor causing compounds by similar analysis. Dr. Blayne Hartman, with Hartman Environmental Geoscience, has analyzed cannabis odor control systems and offers the ability to provide the City a qualified opinion on the effectiveness of both the current and any additionally proposed odor mitigation at C4 Industry. The business remains responsible for designing, implementing, and maintaining their odor control solutions. Dr. Hartman’s work is to validate their effectiveness through an objective analysis and to make specific recommendations to the City. Dr. Hartman does not represent any equipment manufacturer and does not design cannabis odor control systems – he has no conflict of interest with C4 Industry or any other cannabis business operating in Cathedral City. Staff has negotiated a contract and scope of work with Dr. Hartman to evaluate the performance of the odor control systems at C4 Industry, both existing and proposed.

Finally, staff has also met with Envirosuite on several occasions. Envirosuite is a leader in environmental intelligence and offers a technology driven, real-time reporting and monitoring service that provides benefits to the City and to cannabis operators. C4 Industry has contracted with Envirosuite to implement a pilot program at their facility, a program that can potentially be expanded citywide. Under the pilot program, cannabis odor reports in the vicinity of C4 Industry would be reported through the Envirosuite platform embedded on the City’s website, collecting information on the location and strength and intensity of the odor.

Envirosuite’s monitors would also collect data on weather, volatile organic compounds (VOCs), and other compounds. All of this data would be made available to the City and the operator in real-time, which is intended to better correlate odor complaints with objective data, informing both City actions and operational changes at C4 Industry. Additional details on this pilot program and partnership are outlined below.

Cannabis Regulations
In its review of cannabis regulations from 15 cities and 3 counties, City staff evaluated seven zoning questions, including questions directed to odor mitigation and odor mitigation plans.

Staff further assessed four questions related to enforcement of odor violations. The complete data collected from this research is attached to the staff report. The zoning and enforcement research is summarized for Coachella, Palm Desert, Palm Springs, Desert Hot Springs, Oakland, and Richmond for each question below.

Zoning

1. What zoning districts are cannabis cultivation, manufacturing, and lab uses permitted?
Upon reviewing neighboring cities in the Coachella Valley such as Coachella, Palm Desert, Palm Springs, and Desert Hot Springs, as well as Oakland and Richmond, it is evident that cannabis uses such as cultivation, manufacturing, distribution, and testing labs uses are typically restricted to industrial zone districts, while dispensaries are permitted in both industrial and retail zones. Cultivation, manufacturing, distribution, and testing labs uses are generally not permitted within commercial or residential zones, reflecting a common zoning practice aimed at minimizing potential impacts on retail areas and neighborhoods.

2. What separation requirements existing between cannabis uses and either residential zones or uses and other sensitive uses? Identify both the use and the separation requirement.

The separation requirements from residential uses vary significantly. Under the California Business and Professions Code (BPC) Section 26054(b), cannabis businesses shall not be located within a 600-foot radius of a school providing K-12 instruction, a daycare center, or a youth center. Cities and counties, at a minimum, must implement this standard, although they may adopt more stringent standards, including other separation requirements.

As an illustration, Palm Springs established a 1,000-foot separation requirement between cannabis cultivation and manufacturing and a residential zoning district.

Coachella, Lancaster, and Pasadena each have a 600-foot separation requirement from commercial cannabis uses and residentially zoned property. Grover Beach requires a 100-foot setback between retailers and residential zones.

The other cities studied as part of this evaluation do not have an explicit separation from cannabis uses and residential zones or uses. Cathedral City is the only city evaluated that allows cultivation, manufacturing, and distribution in a commercial zoning district. The other cities limit those uses to industrial zones, which are generally separated from residential zones.

3. Are there separation requirements between cannabis uses? Palm Desert requires that cannabis retailers be 1,500 feet apart and similarly requires cannabis businesses within their service industrial zoning district to be separated by 1,500 feet. With some exceptions, Palm Springs requires cannabis businesses be separated by 500 feet. Among the other cities studied, Long Beach has a 1,000 foot separation requirement between dispensaries.

4. Are there limits on either the number or size of cannabis uses? A review of other city regulations shows that other cities place limits on the number of cannabis dispensaries allowed, often setting the cap between three and 10. In contrast, most do not impose limits on other types of cannabis operations, including cultivation, manufacturing, distribution, and testing laboratories. This reflects a regulatory trend aimed at controlling the retail presence of cannabis while allowing more flexibility for non-retail sectors of the industry. Santa Cruz and Moreno Valley are two cities that have additional requirements for cultivation facilities. Santa Cruz restricts indoor cultivation to a maximum of 10,000 square feet. Moreno Valley restricts the total area of the premises designated/used for the cultivation canopy to no more than 22,000 square feet, effectively prohibiting large indoor cultivation facilities, as defined by the DCC. Pasadena limits cultivation to four licensed facilities.

5. What is the definition of a nuisance cannabis odor?
Nuisance cannabis odor is not consistently defined across all city zoning codes.

However, some cities have established specific standards to address this issue. For example, the City of Palm Springs defines “Odor Detection Threshold” as the threshold for the detection of odorous contaminants when one volume of the odorous air has been diluted with seven or more volumes of odor free air as measured by any instrument, device, or any other method designated by the City.

Similarly, the City of Coachella defines "Odor Threshold Concentration" as the lowest concentration of Odorous matter that produces an olfactory response in normal human beings. Odor thresholds shall be determined in accordance with the American Society for Testing and Materials Test Method D1391-57 (reconfirmed to 1967) or in an equivalent manner acceptable to the zoning administrator.

These definitions require measurement through an olfactometer, such as the St.

Croix Sensory Nasal Ranger Field Olfactometer. The specialized device uses a combination of human nose and an instrument to detect and measure odors. While the definition has been adopted by some cities and counties, including Santa Barbara County most recently, it remains a subjective measurement and is not widely accepted as an effective way of detecting cannabis odor.

6. What are the odor mitigation requirements, either through a CUP or cannabis license? Are there specific requirements or standards for cultivation and manufacturing uses? Odor mitigation requirements are standard among the cities researched and are consistent with Cathedral City’s requirements that a business install odor absorbing ventilation and exhaust system so that odor generated inside the cannabis business are not detected outside. The systems include an exhaust air filtration system with odor control that prevents internal odors from being emitted externally; or an air system that creates negative air pressure between the interior and exterior so that the odors generated inside the cannabis business are not detectable outside.

7. Does the city or county require an odor mitigation plan or permit? If so, who is authorized to prepare and submit it? What are the submission requirements? Does it need to be renewed annually as part of the license? Who approves it? A common requirement found in the cities researched is the requirement to develop and implement a ventilation or odor control plan. These plans are required to include detailed information about the proposed ventilation system, including technical specifications indicating that the system can prevent the release of cannabis odors into the atmosphere from the cultivation or manufacturing operation. Coachella, Desert Hot Springs, and Palm Springs all require odor control plans. These are most often prepared by a licensed mechanical engineer. While Palm Springs requires an odor control plan to be prepared as part of a conditional use permit, other cities require it as a post-entitlement permit reviewed administratively and concurrent with a building permit. Some cities, including Palm Springs, use a third-party contractor to review odor control plans. Among the other cities, Grover Beach requires odor control systems to be certified annually.

Code Enforcement

8. What constitutes an odor violation? Are there thresholds or measurements for cannabis odor, either for the concentration of odor or the time period over which it is detected?
National City, La Mesa, and Desert Hot Springs require that odor not be detectable at the property line. El Dorado County uses the St. Croix Sensory Nasal Ranger Field Olfactometer, and Santa Barbara County established a nuisance threshold relying on an olfactometer as part of its recent cannabis code updates. Desert Hot Springs reported that it discontinued its use of the Nasal Ranger.

9. When there is an odor complaint, how is it investigated? Does the cannabis business have a period of time to correct a violation before a citation or further action is taken? If so, how long?
Several cities and counties require cannabis businesses to respond to cannabis odor complaints, including Santa Barbara County, Long Beach, and Desert Hot Springs.

Palm Springs allows cannabis businesses with a compliant odor control plan seven days to correct an odor issue.

10.What are the fines for a violation of the cannabis ordinance? Are there penalties beyond fines? If so, what?
Palm Springs has an escalating enforcement process. For odor violations related to a cannabis business with a compliant odor control plan, a cannabis business is first issued a written warning and given seven days to modify their odor control plan to mitigate odor issues. If the odor cannot be mitigated within seven days, the use must cease until effective odor control measures are in place. For odor violations with a non-compliant odor control plan, the business can be subject to a $10,000 administrative violation and have 30 days to remedy the odor issue and comply with their odor control plan before they’re issued another administrative citation of $10,000.

After three administrative citations, the permit shall automatically be revoked.

Desert Hot Springs code allows fines up to $1,000 per day, although their staff indicates that they have never needed to issue this fine.

11.Are there any unique provisions, such as a hearing officer, that warrant further evaluation?
Stanislaus County established a hearing officer process to conduct administrative hearings to determine whether the conditions described in the notice of violation, administrative citation and order to abate, and notice of hearing constitute a nuisance.

The hearing officer also considers the suspension, revocation, or non-renewal of cannabis permits.

Desert Hot Springs contracts with a third-party for all cannabis ordinance enforcement. Palm Springs contracts for the review of odor control plans.

Cannabis Consultant Support
On April 14, a scope of work for consultant support related to cannabis odor control was issued to four companies. This scope of work builds on the city and county research performed by City staff and seeks specific subject matter expertise on cannabis odor control.

It divides the work into six areas:

1. Regulatory review and best practices assessment

2. Odor control technology evaluation

3. Odor control permitting process

4. Inspection and verification protocols

5. Stakeholder engagement and presentations

6. Training
The full scope of work is attached for reference. It also included a timeline prepared by City staff leading to the presentation of an ordinance to the Cannabis Task Force and Planning Commission in August 2025 and the City Council in September 2025. Staff would be responsible for preparing the ordinance, but with input from the consultant to ensure the City is setting clear and appropriate standards and that the ordinance is accompanied by checklists and supporting documentation for any new processes.

In addition to this scope of work, a contract has been executed with Hartman Environmental Geoscience, the fifth consultant staff met with, specifically for the review of the odor control systems at C4 Industry, both existing and proposed. This contract allows up to 50 hours of consultant time and accounts for two site visits. Through the scope of work, they are tasked with providing the City a qualified opinion on the effectiveness of both the current and proposed odor mitigation plans and make specific recommendations to improve the effectiveness of the existing and any additionally proposed odor mitigation. This contract is not to support C4 Industry but rather to support the City in its review and assessment of the odor problem at C4 Industry using objective analysis and data.

Envirosuite
The City’s current process to report cannabis odors is inefficient and relies upon a platform that was not designed or intended for odor reporting. While it has been used to aggregate complaints, the information reported through the platform is not shared with a cannabis business in real-time. The auto-generated responses to a reporting party when a complaint is made are the same as any other code compliance case, which sets an expectation with the reporting party that the City will respond to their complaint individually. The volume of cannabis odor complaints has precluded staff from investigating and responding to each individual complaint. When the complaints are closed out by City staff, residents feel they are being ignored as the underlying issue has not been addressed. To address this, staff created an email distribution group that it has been sending weekly updates to both in response to cannabis odor complaints at C4 Industry and with respect to the cannabis moratorium.

Through the pilot program with Envirosuite, the City has an opportunity to substantially improve cannabis odor reporting for the area around C4 Industry. This could potentially be expanded to other areas of the City, but beginning in May 2025 an online form will be made available on the City’s website similar to what has been deployed in Des Moines, IA:
https://www.dsm.city/departments/neighborhood_services/odor.php.

The form will document the time and date of the complaint, location, description, and optional contact information for follow-up. Once submitted, City code compliance staff would be notified of a new complaint. Envirosuite would validate the plausibility of the complaint based on atmospheric conditions, including wind direction and speed, and the location of the complaint. Envirosuite also collects time-aligned sensor data and meteorological data. The sensors will be monitoring VOC, H2S and NH3 and can be programmed to monitor two additional compounds as may be directed by the City and its consultants.

Validated complaints are assigned to the business operator, in this case C4 Industry, for investigation and response. While the City does not presently have a response timeline for cannabis businesses to address odor complaints, the pilot program establishes an initial response time of 30 minutes during business hours and 90 minutes after hours, which would include an acknowledgement of the complaint, time of receipt, and immediate investigative steps. Under the pilot program, C4 Industry would be required to post a detailed investigation summary within 24 hours, including on-site observations, source identification (if any), and mitigation actions. Code compliance staff would be responsible for reviewing the investigation conducted by the business in response to a complaint, including its resolution.

The City’s role in the pilot program would be to support its implementation through the City website and to maintain oversight of it for the purpose of regulatory compliance, the tracking of complaints, and community engagement. The pilot program is proposed for a period of six-months, through which Envirosuite, C4 Industry, and the City will evaluate its effectiveness. The pilot program can be extended for an additional six-months upon mutual agreement.

Beyond its application in the area around C4 Industry, City staff are exploring the potential deployment of additional Envirosuite sensors and weather stations elsewhere in the City to permit cannabis odor reporting and monitoring through the Envirosuite platform. There is no estimated cost for these additional services at this point. They will be assessed and evaluated under the cannabis moratorium.

Next Steps
Staff anticipates that it will award a professional services contract to a cannabis consultant in the beginning of May and that staff and the consultant will immediately begin to identify those best practices the City should model in its updated cannabis regulations, including any new odor control requirements. The consultant is expected to produce an odor control permitting process for the City, including submittal and inspection checklists. While a substantial amount of work remains, staff has developed a timeline that would result in the presentation of an ordinance to the Cannabis Task Force and Planning Commission in August 2025 and City Council in September 2025.

FISCAL IMPACT:

The contract with Hartman Environmental Geoscience is not to exceed $12,500 and will be accommodated within the existing budget. The scope of work for the other consultant support was issued on April 14, 2025, for an informal bid with the expectation that it will be within the city manager’s signature authority. This contract is expected to be split between two fiscal years and will be accommodated within the existing and proposed budget.

FIVE-YEAR STRATEGIC PLAN:

F-17 – Review and update, as needed, our ordinances, policies, and practices regarding cannabis.

ATTACHMENTS:

1. City and County Cannabis Analysis

2. Cannabis Consultant Support Scope of Work
Cathedral City – Regulatory Review - Cannabis Odor Control www.scsengineers.com Page E
Appendix E
Odor Abatement Plan Template Checklists for Various Cannabis Facility Types
Cathedral City – Regulatory Review - Cannabis Odor Control www.scsengineers.com Appendix Page E-1
Cannabis Cultivation & Manufacturing (Processing)
Odor Abatement Plan (OAP) Checklist Template
1) Introduction and Source Identification
□ Operator Name
□ OAP Certifier/Author Details
□ Facility Name
□ Facility Address
□ APN(s)
□ Vicinity map with adjacent landuse / zoning with spatial distances between cannabis facility and proximal sensitive receptors
□ Facility floorplans with accurately dimensioned operational facility layout, and room use designations (e.g.: trimming room, cure room, greenhouses, nursery areas, cloning rooms, etc.)
□ Description of operations, any phased construction, details on existing operations and proposed operations, if differs
2) Description of Odor Emitting Activities or Processes □ Identification of odor emitting activities and processes □ Identification of odorants
□ Material Storage/Waste Generation
□ Operational/Production Schedules
□ Fugitive Sources
3) Description of Methods used for Odor Control
□ Active Odor Control System Design
• Odor control facility plan with odor control system callouts, including odor control system type, location of odor control devices, device quantity • Detailed description of proposed odor control devices, including location, quantity and system integration
□ Administrative Controls
• Daily site and system inspections
• Odor control system maintenance log
• Filter replacement schedule and log
• Housekeeping controls: keeping facility doors closed, use of air curtains at egresses, strip curtains at man doors and loading bays
□ Engineering Controls
• Odor control system design: e.g.: carbon filtration, multi-stage filtration, vapor phase, vegetative buffering and any other odor control systems to be implemented
• Ensuring proper air exchanges 3-4 per hour with odor control system/HVAC • Use of negative pressure to help facilitate odor control in sealed buildings • Description of all equipment and methods to be used for reducing odors • Inclusion of technical specifications and O&M materials provided by the odor control system manufacturer
• Example odor inspection logs, inspection checklists and example odor complaint response forms
□ Required Site Preparation
• Repairing paneling, installing vapor barriers, walls and ensuring building envelope is sealed, if retrofitting/tenant improvement an existing structure Cathedral City – Regulatory Review - Cannabis Odor Control www.scsengineers.com Appendix Page E-2
there’s acknowledgement of repairing broken panels or closing gaps to ensure a tight sealed building envelope.
• Ensure existing/proposed electrical system can accommodate the proposed odor control system, some carbon scrubbers require substantial electrical loads. • Details on improvements to HVAC system to accommodate odor control systems • Cannabis processing areas are isolated from administrative areas • Entry areas with secondary door containment, and air filtering systems • Cannabis processing areas equipped with cooler panel walls and ceilings • Roll-up and slide doors equipped with good seals
□ Process Parameters for Proper Operation
• System testing and odor sampling to ensure system efficacy □ Maintenance Requirements
• Filter replacement schedule (quarterly recommended)
• Daily system checks and facility walks
□ Staff Training
4) Complaint Management Procedures
□ Facility Odor Complaint Point-of-Contact Information
□ Complaint Management System description
□ Procedures for Response
□ Community Outreach, if applicable
□ Acknowledgement of departmental access
5) Corrective Action Plan, if required. See Section 5.1.3 for more detail.

Cathedral City – Regulatory Review - Cannabis Odor Control www.scsengineers.com Appendix Page E-3
Cannabis Dispensaries (Retail Storefronts)
Odor Abatement Plan (OAP) Checklist Template
1) Introduction and Source Identification
□ Facility Name
□ Facility Address / Assessor’s Parcel Number(s) (APN)
□ Vicinity & Zoning Map
□ Site Map including entrances/exits, ventilation points □ Description of Facility Operations and Layout (e.g., retail floor, storage areas, security checkpoints)
2) Description of Odor Emitting Activities or Processes □ Identification of Odor Emitting Activities (e.g., display of cannabis products, product handling, packaging removal)
□ Identification of Potential Odorants (e.g., dried cannabis flower, concentrates, infused products)
□ Product Storage Details (including secured areas)
□ Waste Generation and Disposal Practices (e.g., expired product disposal, packaging waste)
□ Operational Schedules (hours of operation, delivery schedules) □ Potential Fugitive Odor Sources (e.g., entrance/exit air exchanges, storage room ventilation, product handling zones)
3) Description of Methods Used for Odor Control
□ Administrative Controls (e.g., odor-free product display protocols, customer handling guidelines)
□ Engineering Controls (e.g., carbon filtration systems, air curtains at entry points, HVAC filtration upgrades)
□ Process Parameters for Proper Operation (e.g., ventilation system performance per mechanical plan)
□ Maintenance Requirements (e.g., filter replacement schedules, ventilation system inspections)
□ Staff Training (odor management awareness, incident response procedures) □ OAP Certification by Certified Industrial Hygienist (CIH) or Professional Engineer (PE) 4) Complaint Management Procedures
□ Facility Contact Information (Odor complaint point-of-contact) □ Complaint Management System (e.g., log system, reporting protocols) □ Procedures for Investigation and Response
□ Community Outreach, if applicable (e.g., contact signage, neighborhood relations) 5) Corrective Action Plan, if Required
□ Steps to Investigate, Address, and Prevent Recurrence of Verified Odor Complaints.

See Section 5.1.3 for more detail.

Cathedral City – Regulatory Review - Cannabis Odor Control www.scsengineers.com Appendix Page E-4
Cannabis Consumption Lounges
Odor Abatement Plan (OAP) Checklist Template
1) Introduction and Source Identification
□ Facility Name
□ Facility Address / Assessor’s Parcel Number(s) (APN)
□ Vicinity & Zoning Map
□ Site Map including all consumption areas, ventilation points, and adjacent uses □ Description of Facility Operations and Layout (e.g., consumption lounge, retail area, private rooms, outdoor patios)
2) Description of Odor Emitting Activities or Processes □ Identification of Odor Emitting Activities (e.g., on-site smoking, vaping, edible consumption with residual odors)
□ Identification of Primary Odorants (e.g., cannabis smoke, vapor emissions, lingering odors)
□ Product Storage Details (if applicable)
□ Waste Generation and Disposal Practices (e.g., ash disposal, used vape cartridge management)
□ Operational Schedules (hours of operation, special events) □ Fugitive Odor Sources (e.g., door openings, patio areas, ventilation exhaust points) 3) Description of Methods Used for Odor Control
□ Administrative Controls (e.g., consumption area restrictions, designated smoking zones, door closure protocols)
□ Engineering Controls (e.g., high-efficiency carbon filtration, negative air pressure systems, enclosed smoking areas, exhaust stack placement) □ Process Parameters for Proper Operation (e.g., air exchange rates, airflow rates, filtration performance standards)
□ Maintenance Requirements (e.g., filter replacements, ventilation inspections, smoke evacuation systems)
□ Staff Training (odor management practices, incident handling, system operation) □ OAP Certification by Certified Industrial Hygienist (CIH) or Professional Engineer (PE) 4) Complaint Management Procedures
□ Facility Contact Information for Odor Concerns
□ Complaint Management System (e.g., community hotline, incident logs) □ Procedures for Response and Documentation
□ Community Outreach, if applicable (e.g., neighborhood meetings, communication channels)
5) Corrective Action Plan, if Required. See Section 5.1.3 for more detail. □ Steps to Investigate, Address, and Prevent Recurrence of Verified Odor Complaints.

See Section 5.1.3 for more detail.

Cathedral City – Regulatory Review - Cannabis Odor Control www.scsengineers.com Page F
Appendix F
City of Cathedral City Licensed Cannabis Business Type and Zoning Maps
Santa Maria, CA July 2025 ±
0 0.5 1 1.5
Miles
FIGURE #1 GENERAL VICINITY

CATHEDRAL CITY

REGULATORY REVIEW
BUSINESS LICENSES | ZONING MAP

CITY OF CATHEDRAL CITY, CA
Legend
Business Types
Cultivation
Dispensary
Distribution
Manufacturing
Microbusiness
Testing Laboratory
City Limits
City Limits
Zoning
Commercial
Industrial
Open Space
Residential
Santa Maria, CA July 2025 ±
0 0.25 0.5 0.75
Miles
Legend
Business Types
Cultivation
Dispensary
Distribution
Manufacturing
Microbusiness
Testing Laboratory
City Limits
City Limits
Zoning
Commercial
Industrial
Open Space
Residential
FIGURE #2 ZOOM EXTENT

CATHEDRAL CITY

REGULATORY REVIEW
BUSINESS LICENSES | ZONING MAP

CITY OF CATHEDRAL CITY, CA
Santa Maria, CA July 2025 ±
0 0.25 0.5 0.75
Miles
Legend
Business Types
Cultivation
City Limits
City Limits
Zoning
Commercial
Industrial
Open Space
Residential
FIGURE #3 CULTIVATION ONLY

CATHEDRAL CITY

REGULATORY REVIEW
BUSINESS LICENSES | ZONING MAP

CITY OF CATHEDRAL CITY, CA
Santa Maria, CA July 2025 ±
0 0.25 0.5 0.75
Miles
Legend
Business Types
Dispensary
City Limits
City Limits
Zoning
Commercial
Industrial
Open Space
Residential
FIGURE #4 DISPENSARY ONLY

CATHEDRAL CITY

REGULATORY REVIEW
BUSINESS LICENSES | ZONING MAP

CITY OF CATHEDRAL CITY, CA
Santa Maria, CA July 2025 ±
0 0.25 0.5 0.75
Miles
Legend
Business Types
Distribution
City Limits
City Limits
Zoning
Commercial
Industrial
Open Space
Residential
FIGURE #5 DISTRIBUTION ONLY

CATHEDRAL CITY

REGULATORY REVIEW
BUSINESS LICENSES | ZONING MAP

CITY OF CATHEDRAL CITY, CA
Santa Maria, CA July 2025 ±
0 0.25 0.5 0.75
Miles
Legend
Business Types
Manufacturing
City Limits
City Limits
Zoning
Commercial
Industrial
Open Space
Residential
FIGURE #6 MANUFACTURING ONLY

CATHEDRAL CITY

REGULATORY REVIEW
BUSINESS LICENSES | ZONING MAP

CITY OF CATHEDRAL CITY, CA
Santa Maria, CA July 2025 ±
0 0.25 0.5 0.75
Miles
Legend
Business Types
Microbusiness
City Limits
City Limits
Zoning
Commercial
Industrial
Open Space
Residential
FIGURE #7 MICROBUSINESS ONLY

CATHEDRAL CITY

REGULATORY REVIEW
BUSINESS LICENSES | ZONING MAP

CITY OF CATHEDRAL CITY, CA
Santa Maria, CA July 2025 ±
0 0.25 0.5 0.75
Miles
Legend
Business Types
Testing Laboratory
City Limits
City Limits
Zoning
Commercial
Industrial
Open Space
Residential
FIGURE #8 TESTING LABORATORY ONLY

CATHEDRAL CITY

REGULATORY REVIEW
BUSINESS LICENSES | ZONING MAP

CITY OF CATHEDRAL CITY, CA
Santa Maria, CA July 2025 ±
0 0.5 1 1.5
Miles
Legend
1000Ft Buffer
Business Type
Cultivation
Manufacturing
Microbusiness
City Limits
Zoning
Commercial
Industrial
Open Space
Residential
FIGURE #9 1000FT BUFFER

CATHEDRAL CITY

REGULATORY REVIEW
BUSINESS LICENSES | ZONING MAP

CITY OF CATHEDRAL CITY, CA
D e s e r t H o t
S p r i n g s
D e s e r t H o t
S p r i n g s
R a n c h o M i r a g e R a n c h o M i r a g e
P a l m
D e s e r t D e s e r t
P a l m S p r i n g s P a l m S p r i n g s
|ÿ111
Ramon Rd
Perez Rd
Date Palm Dr
Av
e
n
di a
M
a
r
a
vil al
Dinah Shore Dr
30th Ave
Date Palm Dr
Landau Blvd
Cathedral Canyon Dr
Gerald Ford Dr
Verona Rd
Vista Chino
D
a
Vall D
r
P
a
ml D
r
Varner Rd
Varner Rd
Edom Hill Rd
R1
R1-S
R1-8.5
R1
R1-12-LH
R1-15-LH
R1-LH
R2
R2
R3
R3
R3-B
RE
RE-HO
RM
RM
RR
RR
P a l m S p r i n g s P a l m S p r i n g s
|ÿ111
C
a
t
h
e
d
ral C
a
n
y
o
n
D
r
Date
P
alm
D
r
Perez Rd
E Palm Canyon Dr
R2
RR
Esri, NASA, NGA, USGS, FEMA, Sources: Esri, TomTom, Garmin, FAO, NOAA, USGS, © OpenStreetMap contributors, and the GIS User Community Z
Path: G:\Project Maps\_Planning\CannabisLocationalRequirements\CannabisLocationalRequirements.aprx | BUFFER ANALYSIS - 1000 Printed: 8/7/2025

CANNABIS CULTIVATION,

MANUFACTURING & DISTRIBUTION WITHIN
CITY OF CATHEDRAL CITY 1000FT OF RESIDENTIAL ZONING
The City of Cathedral City has made every
effort to ensure the accuracy of its data.

Use of this information is the sole
responsibility of the user, The City
Cathedral City assumes no liability
associated with the use or misuse of this
information.
0 1
Cannabis Business Location Mile
Cannabis Location Buffer
(R1) Single Family Residential
(R2) Multiple Family Residential
(R3) Multiple Family Residential
(RE) Residential Estate
(RM) Multiple Family Residential
(RR) Resort Residential
Cities
City Limits
COUNT
42 / 47
WITHIN 1000FT

OF ALL RESIDENTIAL
ZONING
R a n c h o M i r a g e R a n c h o M i r a g e
P a l m S p r i n g s P a l m S p r i n g s
|ÿ111
Ramon Rd
Landau Blvd
Perez Rd
Dinah Shore Dr Dinah Shore Dr
Ramon Rd
Date Palm Dr
D
a
t
e
P
alm
D
r
Gerald Ford Dr
Cathedral Canyon Dr
E Palm Canyon Dr
Ca
t
h
e
d
r
al C
a
n
y
o
n
D
r
PCC
PCC
PCC
PCC
PCC
18 11
26 28
56 Esri, NASA, NGA, USGS, FEMA, Sources: Esri, TomTom, Garmin, FAO, NOAA, USGS, © OpenStreetMap contributors, and the GIS User Community Z
Path: G:\Project Maps\_Planning\CannabisLocationalRequirements\CannabisLocationalRequirements.aprx | Cannabis Business in PCC Printed: 8/7/2025

CANNABIS CULTIVATION,

MANUFACTURING & DISTRIBUTION WITHIN

CITY OF CATHEDRAL CITY ZONING OF PCC
The City of Cathedral City has made every
effort to ensure the accuracy of its data.

Use of this information is the sole
responsibility of the user, The City
Cathedral City assumes no liability
associated with the use or misuse of this
information.
0 1,400
Feet Cannabis Business Location
Planned Community Commercial
Cities
City Limits
ID Business Name Site Address
11 CC Industry, LLC dba C4 USA 69375 Ramon Rd BLDG 1
18 Desert Oasis Group 68031 Ramon Rd STE 201-206
26 EMMI World Management, LLC, Dba Cannamsterdam 67625 East Palm Canyon Dr STE C1-C5 28 Green Dragon Collective #2 67772 East Palm Canyon Dr Bldg A 56 Tempter LLC 34212 Date Palm Dr
##
D e s e r t H o t
S p r i n g s
D e s e r t H o t
S p r i n g s
R a n c h o M i r a g e R a n c h o M i r a g e
P a l m
D e s e r t D e s e r t
P a l m S p r i n g s P a l m S p r i n g s
|ÿ111
Ramon Rd
30th Ave
Perez Rd
A
Date Palm Dr
v
e
n
di a
M
a
r
a
vil al
Dinah Shore Dr
Date Palm Dr
Landau Blvd
Gerald Ford Dr
Verona Rd
Vista Chino
D
a
Vall D
r
P
a
ml D
r
Cathedral Canyon Dr
Varner Rd
Varner Rd
Edom Hill Rd
RR
RR
P a l m
S p r i n g s S p r i n g s
RR
Esri, NASA, NGA, USGS, FEMA, Sources: Esri, TomTom, Garmin, FAO, NOAA, USGS, © OpenStreetMap contributors, and the GIS User Community Z
Path: G:\Project Maps\_Planning\CannabisLocationalRequirements\CannabisLocationalRequirements.aprx | BUFFER ANALYSIS - 300 Printed: 8/7/2025

CANNABIS CULTIVATION,

MANUFACTURING & DISTRIBUTION WITHIN
CITY OF CATHEDRAL CITY 300FT OF ZONING DESIGNATION RR
The City of Cathedral City has made every
effort to ensure the accuracy of its data.

Use of this information is the sole
responsibility of the user, The City
Cathedral City assumes no liability
associated with the use or misuse of this
information.
0 1
Cannabis Business Location Mile
Cannabis Business Buffer
(RR) Resort Residential
Cities
City Limits
COUNT
3 / 47
WITHIN 300FT

OF ZONING

RESORT RESIDENTIAL
City of Cathedral City
Public Hearing Notice
Notice of Availability for Public Review
and Environmental Determination
Notice is hereby given that the Cathedral City City
Council will hold a Public Hearing on the
following:

CASE(S)
Zoning Ordinance Amendment 25-0004

APPLICANT/REPRESENTATIVE
City of Cathedral City
Community and Economic Development Department

PROPOSAL
A proposal to amend the Cathedral City Municipal
Code, including the zoning ordinance, to amend the
licensing (chapter 5.88), permitting and zoning
(chapter 9.108 and section 9.30.030), and
enforcement (section 13.80.240) regulations related
to cannabis uses and to amend various sections of
the Municipal Code relating to administrative fines
contained in titles 1, 3, 5, 8, 9, 11 and 14).

Note that on August 20, 2025, the Planning
Commission conducted a public hearing on the
proposed zoning ordinance amendment and voted 4-
1 to recommend City Council adoption of an
ordinance adopting the proposed amendment.

LOCATION
City-Wide

ENVIRONMENTAL DETERMINATION
The project is exempt from the California
Environmental Quality Act (“CEQA”), pursuant to the
“common sense exemption” set forth in CEQA
Guidelines Section 15061(b)(3), which states that a
project is exempt from CEQA where it can be seen
with certainty that there is no possibility that the
activity in question may have a significant effect on
the environment.

All information regarding the proposed project is
available for public review at the City of Cathedral City Civic Center, Planning Department, 68-700 Avenida
Lalo Guerrero during regular business hours (Monday
through Friday, 8:00 AM - 4:30 PM)

DATE AND TIME OF HEARING
September 24, 2025, at 5:30 PM, or as soon
thereafter as the matter may be heard.

PLACE OF HEARING
Cathedral City Civic Center — Council Chambers
68-700 Avenida Lalo Guerrero
Cathedral City, CA 92234
Any person may appear at the hearing and be heard
in support of, or opposition to, or provide other
testimony on the proposed project or environmental
determination. In addition, persons may also submit
written testimony on the proposed project or
environmental determination, which must be
received by the Project Planner prior to the close of
the public hearing.

The City Council, at the public hearing or during
deliberations, may approve, deny, or propose
changes to the project or to the environmental
determination.

If you challenge any of these items in court, you may
be limited to raising only those issues you or
someone else raised at the public hearing described
in this notice or in written correspondence.

For further information, contact the Project Planner
at:

Andrew Firestine, Director
Community and Economic Development
68-700 Avenida Lalo Guerrero
Cathedral City, CA 92234 (760) 770-0380
NOTE: In compliance with the Americans with
Disability Act, if you need special assistance to
participate in this meeting, please contact the
Planning Department at (760) 770-0340. Notification
48 hours prior to the meeting will enable the city to
make reasonable accommodations to ensure
accessibility to this meeting. {28 CFR 35.104 ADA
TITLE II}
Outlook
Cannabis issues Perez Rd. neighbors. Please give to the task force, planning, and city council.

From John Murphy <[email protected]>
Date Sun 8/10/2025 7:21 AM
To Andrew Firestine <[email protected]>; Talen Weinman <[email protected]> Thank you all for listening to us down here by Perez Rd. And Date Palm. After buying this mobile home in Date Palm Country Club 1.5 years ago, we have suffered continuously with cannabis smells coming INTO the house from underneath through the vents and AC/furnace. It is difficult to be woken up every night with the 'skunk-like' smell. I feel like at times, my retirement has been ruined. Plus, with oxygen dependency due to emphysema, it only makes things worse if one is sensitive like myself. We explored every avenue with the existing AC and furnace to try and mitigate the smell but to no avail. It was being pulled in. We wound up spending $22K dollars for mini-spits which do not pull outside air in. Why should we be financially punished for something we did not create? Most of the cannabis owners know the rules yet seem to not care at all or are not capable of putting in enough machinery to achieve smell mitigation. Mr. Firestine has done an amazing job of setting up some guidelines and expectations of the cannabis growers. I would hope the city passes this and begins demanding action RE the smells.

Everyone down here along the corridor of Perez is being made to suffer. Remember there are many folks employed in the area (car dealers, bars, restaurants, city hall etc.) who have no escape when they go to work. Please do the right thing and make the cannabis growers/producers accountable. They appear to be, by the looks of the remodels, capable of spending the necessary funds to make our area livable. If they can't, shut them down. It's actually pretty simple. Thank you.

John Murphy
137 Via Estrada
CC
760-218-1836
8/11/25, 5:04 PM Cannabis issues Perez Rd. neighbors. Please give to the task force, planning, and city council. - Andrew Firestine - Outlook about:blank?windowId=SecondaryReadingPane1 1/1
Outlook
Cannabis odor regulation
From Kathy Fuller <[email protected]>
Date Tue 7/22/2025 12:28 PM
To Talen Weinman <[email protected]>
You don't often get email from [email protected]. Learn why this is important I read the draft ordinance for the cannabis odor control. I appreciate the City trying to do something about this problem as I am very sensitive to odors and cannabis smell makes me nauseous. Several areas of the city have made me ill with the smell, notably, around the senior citizen center area and Perez.  My question is what are the limits  or standards of the olfactometer reading? I did not see it in the ordinance. The setbacks are a good idea, but what if one can still smell the odor outside the building? I see that there are fines, but what determines if the odor is too strong? Kathryn Fuller, Cathedral City resident
8/11/25, 5:05 PM Cannabis odor regulation - Andrew Firestine - Outlook about:blank?windowId=SecondaryReadingPane1 1/1
Outlook
Draft Cannabis Ordinance Feedback
From Jeff & Erin Fitzpatrick-Bjorn <[email protected]> Date Sat 7/26/2025 1:21 PM
To Talen Weinman <[email protected]>
[You don't often get email from [email protected]. Learn why this is important at https://aka.ms/LearnAboutSenderIdentification ]
CCO Weinman,
We appreciate the opportunity to provide feedback about the proposed ordinance regarding the production, sale, and consumption of cannabis in Cathedral City.

As property owners at Outdoor Resort Palm Springs, we have experienced the cannabis odors released by the cannabis production facility adjacent to the resort along Ramon Road. Despite continued assurances from that business, those bothersome odors have persisted for years.

It seems that this ordinance provides businesses like that one with a clear path to continue operation and the City with a clear path to issue citations and, if needed, revoke licenses in the event of failure to comply.

While we are glad that the City is considering implementation of this ordinance, we remain a bit disappointed that it has taken this long and has the potential to take much longer: this neighboring business could continue to fail to comply for yet another season before losing their license.

Here’s hoping that the City takes prompt action on the ordinance and, if needed, future enforcement — and that businesses such as the one on Ramon Road promptly and consistently comply.

Sincerely,
Jeff & Erin Fitzpatrick-Bjorn
69411 Ramon Road #1198
Cathedral City
8/11/25, 5:07 PM Draft Cannabis Ordinance Feedback - Andrew Firestine - Outlook about:blank?windowId=SecondaryReadingPane1 1/1
Outlook
Re: Draft Cannabis Ordinance Released for Public Review From Rick Watts <[email protected]>
Date Sat 7/19/2025 3:56 PM
To Ernesto Gutierrez <[email protected]>; Mark Carnevale <[email protected]>; Nancy Ross <[email protected]>; Raymond Gregory <[email protected]>; Rita Lamb <[email protected]>; Ryan Hunt <[email protected]>; Talen Weinman <[email protected]>; Andrew Firestine <[email protected]> 1 attachment (54 KB)
Friday July 18, 2025 9-39 AM VOC 535.jpg;
I received the documents sent by Mr. Hunt. The following are my ongoing issues:
1) The glacial speed of which the city is moving on the Cannabis Ordinance update. It will be way over a year since the citizen uprising began. Instead of fast tracking the resolution, the city council continues to drag their feet. Enforce the ordinances already in place. Why isn't that happening? 2) Cathedral City is the only valley city with shockingly absurd low fines for ordinance violations.

Cathedral City has the lowest level of penalties for all cities in the Coachella Valley with cannabis permits. Why is that? Fines and penalties are used as deterrents. It's even mentioned in the attached report by the consulting firm. How many fines have been levied against the C4 complex for ANY violations? I'm guessing the answer is ZERO. Cathedral City should have the same level of fines and penalties as the other cities. Not less. Then again, the monthly revenue tax collected by the city lessens the desire to enforce the existing ordinances. 3) Finally........ the consultant mentioned Volatile Organic Compounds (VOC's) . The odorless, colorless gas that continues to be released into the air by the C4 complex. Attached is a screen shot of a recent VOC reading taken by a monitoring system at my residence on Friday June 18, 2025 at 9:39 AM. It measures an incredible 535. According to Mr. Firestein in an earlier email to me, VOC's are "harmless." Since Mr. Firestein is an expert, perhaps he will explain what chemicals compose the VOC's being released by the C4 complex. All of the residents who live around the C4 complex would be interested in knowing what is contained in the VOC's other than the stink of cannabis. I have seen the VOC level as high as 750.
4) What has happened to the Code Compliance drive by inspections I used to see in the Desert Sands Community? The last time I saw a Code Compliance vehicle was several weeks ago. I frequently see CCPD vehicles passing my residence, mostly in the very early morning hours. At least they have stopped turning on their "Alley Lights" and shining into the windows in my residence. The smell of cannabis has been less because the HVAC systems are running due to the summer heat.

Of course, the "stink number" has diminished as a result. This distorts your calculations contained in the reports. Cannabis reports appears less than it actually is. But I am sure the city council has figured that out.
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5) What happened to the landscaping trees which were included in the original plans at the C4 complex? Trees were supposed to line the masonry walls between the Desert Sands Community and the Outdoor Resort of Palm Springs. The trees were to shield the C4 building from the other communities. All I see is a huge metallic building facing my residence. The city approved plans called for landscaping to block the ugly building. What do we have? Nothing. Any idea(s) how the C4 ownership manages to evade non-compliance to the original approved plans? All of the "fix" work by a consulting firm should be paid for by the ownership of the C4 complex. Not by the Cathedral City taxpayers. How much are the taxpayers being asked to pay for the consultant and equipment? How much is the C4 ownership being asked to pay for these expenditures? I suspect the answer is ZERO. By the time the city finishes messing around with the E-Z to fix problem, the Canadian's (well most of them) will be back in the valley to find out nothing has changed since they left in April/May.

Here is my prediction: I will be writing emails to the city council on this same topic well into 2026. The talk will continue but little else will be accomplished. I welcome any communication from anyone at city government.

Regards,
Rick Watts
1322 Via Poco (400 yards directly south of the C4 complex) Desert Sands Community
Cathedral City, Ca. 92234
[email protected]
760-408-3578
From: Ryan Hunt <[email protected]>
Sent: Thursday, July 17, 2025 1:21 PM
To: Ryan Hunt <[email protected]>
Subject: Draft Cannabis Ordinance Released for Public Review Dear Valued Community Member,
Here is your latest update on the City's cannabis enforcement activities and a major milestone in our regulatory improvement process:

Draft Cannabis Ordinance Released for Public Review
The City has prepared a comprehensive draft ordinance to update our cannabis regulations and has made it available for public review and comment before formal consideration by the Planning Commission and City Council. This represents our commitment to transparency and community engagement throughout the regulatory development process.

The draft ordinance incorporates months of research, consultant analysis, and data collection to address cannabis odor concerns through:
8/11/25, 5:07 PM Re: Draft Cannabis Ordinance Released for Public Review - Andrew Firestine - Outlook about:blank?windowId=SecondaryReadingPane1 2/4
Mandatory odor control plans for all cannabis businesses with performance-based standards Enhanced enforcement provisions that provide clear corrective action processes Updated zoning requirements including new setback requirements from the Resort Residential zone
Public Comment Opportunity
The draft ordinance and supporting materials are also available for review at:
https://www.cathedralcity.gov/Home/Components/News/News/2378/ Community members are encouraged to review these documents and submit comments electronically to Code Compliance Officer Talen Weinman at [email protected].

Upcoming Public Hearings:

Planning Commission: August 20, 2025 (tentative)
City Council: September 24, 2025 (tentative)
Interested parties are encouraged to monitor the City's website for published meeting agendas and information on how to participate in public hearings.

Timeline Commitment
The City remains on track with the timeline presented to City Council in April 2025. The draft ordinance represents the culmination of extensive research into best practices from other California jurisdictions, professional consultation with SCS Engineers, and ongoing monitoring data from our Code Compliance Division.

This transparent approach ensures that our community has ample opportunity to review and provide input on proposed regulations before they are formally considered for adoption.

Please continue to report any cannabis-related concerns through our online reporting system at https://www.cathedralcity.gov/i-want-to/contact/report-an-issue or the free MyCathedralCity mobile app.

Best regards,
Ryan Hunt, CPC
Communications & Events Manager
City of Cathedral City, California
[email protected]
Cell: 540.664.8556|Monday-Thursday 7 a.m. – 6 p.m.
8/11/25, 5:07 PM Re: Draft Cannabis Ordinance Released for Public Review - Andrew Firestine - Outlook about:blank?windowId=SecondaryReadingPane1 3/4
8/11/25, 5:07 PM Re: Draft Cannabis Ordinance Released for Public Review - Andrew Firestine - Outlook about:blank?windowId=SecondaryReadingPane1 4/4
Scott McDonald
69411 Ramon Road
Cathedral city, CA
92234
2025 August 18
Mayor and City Council
City of Cathedral City
68-700 Avenida Lalo Guerrero
Cathedral City, CA 92234
Subject: Urgent Strengthening of Cannabis Odor & Emissions Ordinance Dear Mayor, Councilmembers, Commissioners, and Task Force Members:

I live directly adjacent to a cannabis cultivation facility. Since the opening of C4 Industries, my neighbors and I have endured intrusive odors and emissions that interfere with daily life, reduce property enjoyment, lower property values, and raise serious health concerns.

While I appreciate the City’s efforts to update the cannabis odor ordinance, the current draft contains major flaws that will delay relief, weaken enforcement, and fail to address key public health risks.

Key Concerns
● Compliance Delay – Existing operators have until December 31, 2026 to install odor control equipment, leaving residents exposed for two more years. ● Weak Enforcement – Verified violations result in warnings and grace periods instead of immediate citations. The city has not issued an odor violation since 2019. ● High Odor Threshold – The 7 DT standard still permits disruptive odors and is not protective of residents.
● Self-Certification – Annual operator self-certification is inadequate; independent third-party verification is essential.
● VOC & Chemical Risks – Emissions include VOCs (terpenes) and potentially hazardous pesticides, fertilizers, and odor-masking agents. Boilers and chillers may release additional chemicals. No monitoring or health risk assessment is required yet it is the release of these compounds that result in verified negative health consequences such as burning eyes, skin irritation, congestion, etc. ● Unjustified Buffer Zones – Distances appear based on zoning convenience, not peer-reviewed studies or air dispersion modeling.
● Lack of Transparency – Residents have no access to odor test results or meteorological sensor data.

Requested Fixes
● Require odor control plan approval within 90 days and equipment operational within 6 months.
● Impose immediate citations for verified violations.
● Adopt a lower, health-protective odor threshold.
● Mandate annual independent third-party verification.
● Require disclosure of all chemicals used in cultivation, processing, boilers, chillers, and odor systems.
● Conduct independent VOC monitoring and health risk assessments, with public reporting.
● Reevaluate buffer zones using independent science and modeling. ● Publish odor and air quality data for public access.

Accountability Questions
● Why delay compliance until 2026?
● Why use warnings instead of citations for verified violations? ● What scientific evidence supports a 7 DT standard as protective? ● Why rely on operator self-certification instead of independent verification? ● What safeguards protect schools, seniors, and vulnerable populations? ● What hazardous chemicals are used, and how are residents protected? ● Has the City conducted a health risk assessment of cannabis emissions? ● What data support current buffer zones?
● Will monitoring data be made publicly accessible in real time? ● Why is enforcement handled by the same department that promotes cannabis development, creating a conflict of interest?
● What protections exist for residents who report odors, so complaints are not dismissed?
● Will the City commit to contracting independent experts for monitoring and enforcement?
I urge the Council to strengthen this ordinance and require written responses to these questions in the public record. Residents deserve protection now, not years from now.

Sincerely,

CANNABIS TASK FORCE

MINUTES
Regular Meeting 4:00 PM
Monday, August 18, 2025
City Hall
Study Session Room
68-700 Avenida Lalo Guerrero
Cathedral City, CA 92234

CALL TO ORDER
City Manager Charles McClendon called the meeting to order at 4:00 p.m.

ROLL CALL
Members Present:

Kenneth Churchill, Member
Danny Lee, Member
James Lawrence, Member
John Ramistella, Member
Matthew Goodman, Member
Members Absent:

Armando Perez, Member
Staff Present:

Tracey Hermosillo, City Clerk
Charles McClendon, City Manager
Anne Ambrose, Assistant City Manager
Andrew Firestine, Community and Economic Development Director Justin Gardiner, Code Compliance Manager
Kevin Biersack, Financial Services Director
Kevin Reza-Ayala, Analyst II
Manuel Rocha, Assistant Planner
Talen Weinman, Code compliance Officer

1. APPROVAL OF MINUTES
A. Accept the February 24, 2025 Minutes.

A motion was made by Member Lee and seconded by Member Lawrence to accept the February 24, 2025 Cannabis Task Force Minutes.

RESULT: PASS
MOVER: Danny Lee, Member
SECONDER: James Lawrence, Member
AYES: Churchill, Lee, Lawrence, Ramistella, Goodman
ABSENT: Perez

2. AGENDA
A. Cannabis Ordinance Amendments
Recommendation: This item is presented for information, discussion and possible recommendation to City Council.

City Manager Charles McClendon introduced Andrew Firestine, Community and Economic Development Director, who provided an overview of the Cannabis Ordinance and proposed update. He noted that the following members of the team from SCS Engineers were also in attendance and available for questions:

Paul Schafer
Christopher Petro
Eva Luu
Armando Hurtado-Garcia
He covered the following points:
• A background of ordinances regulating the licensing of cannabis businesses
• The number of cannabis businesses and licenses
• Issues related to cannabis odor
• The responses to issues related to cannabis odor
• Ongoing challenges
• The enactment of a moratorium on the approval of new cannabis licenses and conditional use permits and the issuance of building permits for the build-out or expansion of new cannabis businesses • The extension of the moratorium
• Actions staff has taken since the moratorium was put in place • Review of cannabis regulations related to zoning
• Review of cannabis regulations related to separation requirements • Review of cannabis regulations – odor control
• Review of cannabis regulations – odor enforcement
• Cannabis research – what other cities and counties are doing o Zoning questions asked
o Enforcement questions asked
• Review of zoning questions
• Consultant support of SCS Engineers
• SCS Engineers Report
• Odor control technology
• Overview of the proposed Ordinance
o Zoning Regulations
o Odor Control Plans
o Enforcement
o Licensing
o Cannabis Tax
• Review of alternatives and other considerations
• Overview of public outreach and engagement
• Recommendation that will be made to the City Council
There was discussion among the members of the committee, concerns were expressed, and questions were raised. Staff responded to questions raised and provided clarification along with members of the SCS Engineers team.

A motion was made by Member Churchill and seconded by Member Ramistella to recommend that the proposed Ordinance presented by staff be presented to the City Council for consideration and approval.

RESULT: PASS
MOVER: Kenneth Churchill, Member
SECONDER: John Ramistella, Member
AYES: Churchill, Lee, Lawrence, Ramistella
NOES: Goodman
ABSENT: Perez

3. PUBLIC COMMENTS
There were no members of the public in attendance.

ADJOURNMENT
City Manager Charles McClendon adjourned the Cannabis Task Force Meeting at 5:30 p.m.

Chair, City of Cathedral City Secretary, City of Cathedral City

PLANNING COMMISSION

MINUTES
Regular Meeting 6:00 PM
Wednesday, August 20, 2025
City Council Chambers
68-700 Avenida Lalo Guerrero
Cathedral City, CA 92234
CHAIR
Danny Lee

PLANNING COMMISSION MEMBERS
Vice-Chair
Danielle Mead
Commissioner
Peter Bedard
Commissioner
Rich Malacoff
Commissioner
Roy MacPhail

CALL TO ORDER
Chair Danny Lee called the meeting to order at 6:00 p.m.

ROLL CALL
Members Present:

Danny Lee, Chair
Danielle Mead, Vice Chair
Rich Malacoff, Commissioner
Roy MacPhail, Commissioner
Peter Bedard, Commissioner
Members Absent:

None
Staff Present:

Andrew Firestine, Director of Community and Economic Development Sandra Molina, Deputy Director of Community and Economic Development Stephanie Gutierrez, Assistant City Attorney
Cynthia Schultz, Associate Planner

PLEDGE OF ALLEGIANCE
Chair Lee led the Pledge of Allegiance.

AGENDA FINALIZATION
There were no changes to the agenda.

1. PUBLIC COMMENTS
There were no members of the public that wished to speak.

2. PUBLIC HEARING ITEMS
A. Zoning Ordinance Amendment 25-0004
Recommendation: Adopt a resolution recommending that the City Council approve an ordinance amending the Cathedral City Municipal Code, including the zoning ordinance, to amend the cannabis tax (chapter 3.48), licensing (chapter 5.88), permitting and zoning (chapter 9.108 and section 9.30.030), and enforcement (section 13.80.240) regulations related to cannabis uses and to amend various sections of the Municipal Code relating to administrative fines contained in titles 1, 3, 5, 8, 9, 11 and 14).

Andrew Firestine, Director of Community and Economic Development, provided the presentation and responded to questions.

Consultant, Armando Hurtado, SCS Engineers, responded to comments raised by the Commission.

Chair Lee opened the Public Hearing to receive public comments.

Public Comments:

Scott McDonald, Cathedral City, submitted written comments for the record.

Chair Lee closed the Public Hearing and returned discussion to the Commission.

The Commission took a brief recess at 7:51 p.m.

The Commission reconvened at 7:57 p.m.

A motion was made by Chair Lee and seconded by Commissioner MacPhail to approve staff’s recommendation as presented.

Discussion ensued regarding the implementation of separation requirements between cannabis businesses, and between cannabis uses and sensitive uses, including the Cathedral City Community Amphitheater, residential areas, adult daycares, places of worship, social service agencies, and parks.

Additionally, the Commission discussed the potential inclusion of a 7-day correction or cease operations action for odor-related issues, limits on the maximum size of cannabis cultivation facilities and public engagement requirements for future large cultivation facilities.

Following discussion, the Commission supported the deletion of cannabis cultivation uses in the PCC zone district, elected not to take action on any of the items discussed, with the exception of cannabis cultivation facility size limitations. The Commission expressed support for aligning the maximum size of future cannabis cultivation facilities to a maximum canopy area of 22,000 square feet, consistent with size limitations of the State’s Department of Cannabis Control, for large indoor cultivation facilities.

A motion was made by Vice Chair Mead and seconded Commissioner Bedard to accept an amendment to the proposed motion to include limits on the maximum size of cannabis cultivation facilities to 22,000 square feet of canopy area, in alignment with the State’s Department of Cannabis Compliance size categories and definition of a large indoor cultivation facility.

RESULT: PASS
MOVER: Danielle Mead, Vice-Chair
SECONDER: Peter Bedard, Commissioner
AYES: Lee, MacPhail, Mead, Bedard
NOES: Malacoff
A motion was made by Chair Lee and seconded by Commissioner MacPhail to adopt a resolution recommending that the City Council approve an ordinance amending the Cathedral City Municipal Code, including the zoning ordinance, to amend the cannabis tax (chapter 3.48), licensing (chapter 5.88), permitting and zoning (chapter 9.108 and section 9.30.030), and enforcement (section 13.80.240) regulations related to cannabis uses and to amend various sections of the Municipal Code relating to administrative fines contained in titles 1, 3, 5, 8, 9, 11 and 14) with the inclusion of limits on the maximum size of cannabis facilities to align with the State’s Department of Cannabis size categories and definition of a large indoor cultivation facility.

RESULT: PASS
MOVER: Danny Lee, Chair
SECONDER: Roy MacPhail, Commissioner
AYES: Lee, MacPhail, Mead, Bedard
NOES: Malacoff

3. NON-PUBLIC HEARING ITEMS
A. Development Code Update
Recommendation: For discussion.

Cynthia Schultz, Associate Planner, provided the update.

This item was advisory with no formal action taken by the Commission.

4. COMMISSIONER'S COMMENTS
Commissioner Bedard inquired about certain medians in the City that are no longer landscaped.

Chair Lee recommended Commissioner Bedard speak with Public Works Manager Deanna Pressgrove for an update.

Commissioner Malacoff discussed the upcoming opportunity to tour the Kings School campus.

5. CITY ATTORNEY COMMENTS
There were no comments from the City Attorney.

6. STAFF COMMENTS
A. Work Plan and Future Agenda Items
There were no staff comments.

ADJOURNMENT
Chair Lee adjourned the meeting at 9:05 p.m.

Danny Lee, Chair Andrew Firestine, Secretary
City of Cathedral City City of Cathedral City
RESOLUTION NO. ______

A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF CATHEDRAL

CITY, CALIFORNIA, AMENDING THE SCHEDULE OF USER AND

REGULATORY FEES FOR VARIOUS CITY SERVICES TO ADD A FEE

FOR THE REVIEW OF AN ODOR CONTROL PLAN AND THE ANNUAL

CERTIFICATION OF AN CONTROL PLAN
WHEREAS, user and regulatory fees are established by the City Council; and WHEREAS, the City recently completed a study to identify the cost of providing various user and regulatory fee-related services; and
WHEREAS, the City Council adopted a schedule of fees through Resolution No. 2025-04 after finding that the study provides adequate evidence to conclude that the fees do not exceed the cost to provide the services for which the fees are charged; and WHEREAS, the schedule of fees contains provisions such that the City Manager may update the various fees based on the percentage change, for 12-months ending March of the current fiscal year, in the All Urban Consumers Price Index (CPI-U) for Riverside-San Bernardino-Ontario, to become effective July 1 of the subsequent fiscal year; and
WHEREAS, in order to assist staff in implementing the requested annual adjustments, if any, Exhibit “A” includes a column identified as “CPI” that illustrates the recommended annual adjustment pattern for the fees set forth in Exhibit “A”; and WHEREAS, this Resolution is adopted based upon the evidence submitted during the April 23, 2025, City Council meeting including, without limitation, all documents presented to the City Council; and
WHEREAS, in adopting this Resolution, the City Council is taking action only on those fees for the services, programs or products set forth in Exhibit “A” which have been modified from prior resolutions of the City Council. The remaining fees that have not been modified from prior resolutions shall remain in full force and effect.

NOW, THEREFORE, THE CITY COUNCIL OF THE CITY OF CATHEDRAL CITY, DOES HEREBY RESOLVE, DETERMINE AND ORDER AS FOLLOWS:

SECTION 1. INCORPORATION OF RECITALS
The City Council hereby finds the recitals set forth above to be true and correct.

SECTION 2. AMENDMENT TO FEE SCHEDULE AND ESTABLISHMENT OF

REVISED CANNABIS LICENSING AND USER PERMIT FEES FOR THE

REVIEW OF AN ODOR CONTROL PLAN AND THE ANNUAL

CERTIFICATION OF AN ODOR CONTROL PLAN
The City Council hereby adopts an amendment to the fee schedule as set forth in attached Exhibit “A” and incorporated by reference.

SECTION 3. EFFECTIVE DATE
This Resolution shall take effect upon adoption.

SECTION 4. CERTIFICATION
The City Clerk shall attest to and certify the vote adopting this Resolution.

PASSED, APPROVED AND ADOPTED at a regular meeting of the City Council of the City of Cathedral City held on this 23rd day of September, 2025, by the following vote:

Ayes:

Noes:

Absent:

Abstain:

Nancy Ross, Mayor
ATTEST:

Tracey R. Hermosillo, City Clerk
APPROVED AS TO FORM:

Eric S. Vail, City Attorney
“Exhibit A”
City of Cathedral City
Master Fee Schedule – Cannabis Licensing and User Permit Fees Fee Description Fee Charge Basis Note CPI
2 Odor Control Plan and Amendments (Cultivation and
Manufacturing)
3 Odor Control Plan and Amendments (Consumption Lounge) 4 Odor Control Plan and Amendments (Dispensary, Distribution, and Testing Lab)
5 Odor Control Plan Annual Certification

$3980
$3980
$480
$480
Each
each
each
each
Y
Y
Y
Y
RESOLUTION NO. ______

A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF CATHEDRAL

CITY, CALIFORNIA, ESTABLISHING A SCHEDULE OF FINES FOR

ISSUING ADMINISTRATIVE CITATIONS IN THE CITY OF CATHEDRAL

CITY AND ESTABLISHING A GREATER ADMINISTRATIVE FINE

AMOUNT FOR A PUBLIC NUISANCE VIOLATION OF CANNABIS ODOR WHEREAS, California Government Code Section 53069.4 authorizes cities to impose and collect administrative fines and penalties for violations of any of its codes and ordinances; and
WHEREAS, the City Council of the City of Cathedral City (“City Council”) adopted Ordinance No. 504, establishing a comprehensive code enforcement program and procedures for the imposition, enforcement, review and collection of administrative penalties for violations of the Cathedral City Municipal Code (“CCMC”), which is codified in Sections 13.58.010 through 13.58.160 of the CCMC; and WHEREAS, the City Council has adopted Ordinance No. _____, amending Section 13.58.020(A) to consolidate the administrative fine schedules within the CCMC into a single section and to authorize the imposition of a fine as set in the CCMC or such amount that the City Council may establish by resolution; and WHEREAS, the City Council has adopted Ordinance No. _____, amending Section 13.80.240(J) to modify the enforcement procedures for a public nuisance violation of cannabis odor; and
WHEREAS, the City Council now desires to adopt a resolution establishing an administrative fine schedule, incorporating the currently established administrative fines for all other violations of the CCMC that exceed the default fine established in Section

13.58.020 of the Cathedral City Municipal Code and establishing a fine greater than the default fine for a public nuisance violation of cannabis odor of up to: 1) $1,000 for each day a violation exists for those cannabis businesses with an approved odor control plan compliant with Sections 5.88 and 9.108 of the CCMC; or 2) $5,000 per month for those cannabis businesses required to obtain approval of an odor control plan pursuant to Chapter 5.88 of the CCMC that have failed to obtain approval of, comply with, or maintain an odor control plan.

NOW, THEREFORE, THE CITY COUNCIL OF THE CITY OF CATHEDRAL CITY, DOES HEREBY RESOLVE, DETERMINE AND ORDER AS FOLLOWS:

SECTION 1. INCORPORATION OF RECITALS
The City Council hereby finds the recitals set forth above to be true and correct.

SECTION 2. ESTABLISHMENT OF ADMINISTRATIVE FINE SCHEDULE The City Council hereby adopts an administrative fine schedule as set forth in attached Exhibit “A” and incorporated by reference.

SECTION 3. EFFECTIVE DATE
This Resolution shall take effect upon adoption.

SECTION 4. CERTIFICATION
The City Clerk shall attest to and certify the vote adopting this Resolution.

PASSED, APPROVED AND ADOPTED at a regular meeting of the City Council of the City of Cathedral City held on this 23rd day of September, 2025, by the following vote:

Ayes:

Noes:

Absent:

Abstain:

Nancy Ross, Mayor
ATTEST:

Tracey R. Hermosillo, City Clerk
APPROVED AS TO FORM:

Eric S. Vail, City Attorney
“Exhibit A”
CCMC
Provision
Chapter Name 1st Administrative
Citation
2nd Administrative
Citation
3rd Administrative
Citation

5.94.030 Plastic Beverage
Straws
1,000a- -

13.80.240(J) Cannabis 1,000/5,000b
a $1,000 per violation
b 1) $1,000 for each day a violation exists for those cannabis businesses with an approved odor control plan compliant with Sections 5.88 and 9.108 of the CCMC; or 2) $5,000 per month for those cannabis businesses required to obtain approval of an odor control plan pursuant to Chapter 5.88 of the CCMC that have failed to obtain approval of, comply with, or maintain an odor control plan
Staff Report
City Council
Item No. 6.A
Meeting Date: September 24, 2025
From: Michael A. Contreras, Fire Chief
Title: Adoption of the Updated Cathedral City Local Hazard Mitigation Plan (LHMP)
RECOMMENDATION:

To adopt the updated Cathedral City Local Hazard Mitigation Plan. This adoption aligns with state and federal requirements for formally adopting hazard mitigation plans.

BACKGROUND:

On November 13, 2024, the City Council awarded a contract to the firm Jacob Green and Associates (JGA) to update the City’s Local Hazard Mitigation Plan. Staff worked closely with JGA to bring the LHMP current and ready for City Council adoption.

The Cathedral City Local Hazard Mitigation Plan is required by the Disaster Mitigation Act of 2000 (DMA 2000), which amended the Robert T. Stafford Disaster Relief and Emergency Assistance Act by adding “Section 322 – Mitigation Planning. Adoption of the plan will also allow the city to pursue federal mitigation grant opportunities including the Hazard Mitigation Grant Program (HMGP) and the Flood Mitigation Assistance (FMA) program.

DISCUSSION:

The City of Cathedral City has partnered with Jacob Green and Associates, a Southern California-based local government consulting firm, to develop the City’s 2025 Local Hazard Mitigation Plan update. The process included receiving input from City staff, stakeholders representing key sectors such as utilities, housing, healthcare, small business, and community-based organizations, as well as the general public. Over the past year, the planning team conducted a hazard risk assessment, analyzed climate impacts and equity considerations, and identified priority mitigation actions aligned with FEMA’s updated guidance issued in April 2023 (while FEMA issued revised guidance in April 2025 making some of these elements optional, including enhanced equity and climate change impacts, Cal OES continues to require both of these in all California hazard mitigation plans).

The LHMP was submitted to Cal OES and FEMA for review in June 2025. In August 2025, FEMA determined the plan is approvable pending adoption, requiring only that the City submit proof of adoption to FEMA for final approval.

Once adopted, the LHMP will serve as the City’s official mitigation strategy for the next five years. The plan will be maintained and updated annually by City staff, in coordination with internal departments, regional agencies, and community stakeholders. Adoption of the plan will also allow the city to pursue federal mitigation grant opportunities including the Hazard Mitigation Grant Program (HMGP), and the Flood Mitigation Assistance (FMA) program.

Community Engagement: The City of Cathedral City prioritized meaningful public and stakeholder engagement throughout the development of the 2025 Local Hazard Mitigation Plan. Community engagement was conducted in both English and Spanish to ensure broad accessibility.

Key outreach activities included:
• Online Public Survey: A multilingual community survey in English and Spanish was available on the City’s website through February 2025, allowing residents to share experiences and perspectives on hazards and mitigation actions. • Workshops and Meetings: A virtual Hazards Workshop was held in December 2024.

An in-person public meeting and a parallel virtual workshop were held in January 2025.
• Public Review Period: The Draft LHMP was posted for a two-week public comment period in May 2025. Feedback was reviewed and incorporated into the final draft.

This engagement strategy ensured input from vulnerable populations including low-income residents, seniors, renters, and individuals with disabilities was considered in the planning process.

Next Steps: Upon receipt of final approval from FEMA, the City will:
• Integrate the adopted LHMP into the Cathedral City General Plan by referencing it in the Safety Element as an appendix or supporting document. • Coordinate internal implementation efforts by working with departments across the City to begin aligning capital improvements, planning policies, and emergency preparedness efforts with the mitigation actions outlined in the plan. • Maintain and update the plan on an ongoing basis, including an annual review of progress toward mitigation goals and a formal plan update every five years in accordance with FEMA requirements.

Adoption of the LHMP positions the City of Cathedral City to pursue funding for high-priority mitigation projects that reduce risk, improve public safety, and strengthen resilience to climate-related and other hazards.

FISCAL IMPACT:

There is no fiscal impact to the Operating Budget. The plan development was included in the FY 2025/26 budget.

FIVE-YEAR STRATEGIC PLAN:

Goal E: Safety
Action E-5: Update the City’s EOC, Conduct EOC drills and training, and update the City’s Emergency Operations Plan and Local Hazard Mitigation Plan.

ATTACHMENTS:

1. Attachment A – Resolution adopting the 2025 LHMP

2. Attachment B – City of Cathedral City 2025 Local Hazard Mitigation Plan 1 RESOLUTION 2025 -

A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF CATHEDRAL CITY, CALIFORNIA, ADOPTING THE 2025 CATHEDRAL CITY LOCAL

HAZARD MITIGATION PLAN UPDATE
WHEREAS, The City of Cathedral City recognizes the threat that natural and manmade hazards pose to people and property within our community; and WHEREAS, undertaking hazard mitigation actions will reduce the potential for harm to people and property from future hazard occurrences; and WHEREAS, the U.S. Congress passed the Disaster Mitigation Act of 2000 (“Disaster Mitigation Act”) emphasizing the need for pre-disaster mitigation of potential hazards; and
WHEREAS, the Disaster Mitigation Act made available hazard mitigation grants to state and local governments; and
WHEREAS, an adopted Local Hazard Mitigation Plan is required as a condition of future funding for mitigation projects under multiple FEMA pre- and post-disaster mitigation grant programs; and
WHEREAS, the City of Cathedral City fully participated in the FEMA-prescribed mitigation planning process to prepare this local hazard mitigation plan; and WHEREAS, the California Office of Emergency Services and Federal Emergency Management Agency, Region IX officials have reviewed the City of Cathedral City Local Hazard Mitigation Plan and approved it contingent upon this official adoption of the participating governing body; and
WHEREAS, the City of Cathedral City desires to comply with the requirements of the Disaster Mitigation Act and to augment its emergency planning efforts by formally adopting the 2025 Cathedral City Local Hazard Mitigation Plan (LHMP) Update; and WHEREAS, adoption by the governing body for the City of Cathedral City demonstrates the jurisdiction’s commitment to fulfilling the mitigation goals and objectives outlined in this Local Hazard Mitigation Plan; and
WHEREAS, adoption of this legitimizes the plan and authorizes responsible agencies to carry out their responsibilities under the plan; and WHEREAS, Cathedral City Fire & EMS recommended to the City Council of Cathedral City that it adopt Cathedral City Fire & EMS’ recommended finding that the City adopt the 2025 LHMP Update;
2 NOW, THEREFORE, BE IT RESOLVED that the City of Cathedral City adopts the City of Cathedral City Local Hazard Mitigation Plan Update as an official plan; and

1. THAT the City of Cathedral City will submit this adoption resolution to FEMA Region IX and the California Office of Emergency Services to enable the plan’s final approval in accordance with the requirements of the Disaster Mitigation Act of 2000.

2. THAT Interim City Manager Anne Ambrose is the appointed agent for the City of Cathedral City.

3. THAT the City Clerk shall certify as to the adoption of this resolution and shall cause the same to be processed in the manner required by law.

PASSED, APPROVED, AND ADOPTED this 24th day of September 2025. ___________________________
Nancy Ross, Mayor
ATTEST:
____________________________
Tracey R. Hermosillo, City Clerk
APPROVED AS TO FORM:
____________________________
Eric S. Vail, City Attorney
I, TRACEY HERMOSILLO, CITY CLERK of the City of Cathedral City, do hereby certify that the foregoing Resolution was introduced and adopted at a regular meeting of the City Council held on the 24th day of September 2025 by the following vote:

AYES:

NOES:

ABSENT:

ABSTAIN:

Tracey R. Hermosillo, City Clerk
Local Hazard Mitigation Plan Update
1 City of Cathedral City 2025 Local Hazard
Mitigation Plan Update
Prepared by
Jacob Green and Associates
13217 Jamboree Rd
Tustin, CA 92782
Local Hazard Mitigation Plan Update
2 (this page intentionally left blank)

Local Hazard Mitigation Plan Update
3 INTRODUCTION .......................................................................................................5 Structure of the 2025 LHMP Update................................................................................. 5 Plan Submission and Approval ....................................................................................... 6 Planning Team............................................................................................................... 6 SECTION 1 – HAZARD MITIGATION.............................................................................8 Hazard Mitigation Planning............................................................................................. 8 SECTION 2 – COMMUNITY PROFILE .........................................................................12

2.1 Setting and Location................................................................................................12

2.2 History....................................................................................................................13

2.3 Climate...................................................................................................................15

2.4 Climate Change.......................................................................................................18

2.5 Demographics.........................................................................................................19

2.6 Housing and Development.......................................................................................21

2.7 Economy.................................................................................................................25

2.8 Infrastructure..........................................................................................................27

2.9 Historically Vulnerable Populations..........................................................................30 SECTION 3 – HAZARD IDENTIFICATION AND RISK ASSESSMENT ...............................32

3.1 Introduction............................................................................................................32

3.2 Identifying Hazards..................................................................................................38

3.3 Hazard Profiles........................................................................................................42 SECTION 4 – VULNERABILITY ASSESSMENT ........................................................... 152

4.1 Introduction..........................................................................................................154

4.2 Hazard-Specific Vulnerability Analysis....................................................................156

4.3 Critical Infrastructure & Key Resources...................................................................204 SECTION 5 – CAPABILITY ASSESSMENT ................................................................. 209

5.1 Planning & Regulatory Capabilities .........................................................................210

5.2 Floodplain Management & Compliance...................................................................216

5.3 Administrative & Technical Capabilities ..................................................................230

5.4 Financial Capabilities ............................................................................................234 Local Hazard Mitigation Plan Update
4 5.5 Community Partnerships & Collaboration ...............................................................235

5.6 Strengths, Weaknesses, Opportunities, and Threats (SWOT) Analysis .......................238

5.7 Opportunities for Improvement ..............................................................................242 SECTION 6 – MITIGATION STRATEGY ...................................................................... 246

6.1 Introduction..........................................................................................................246

6.2 Vision, Goals, & Objectives ....................................................................................248

6.3 Mitigation Actions..................................................................................................251

6.4 Status of Prior Mitigation Actions............................................................................264

6.5 Actions Considered but Not Included......................................................................266

6.6 Implementation & Monitoring.................................................................................268 SECTION 7 – PLANNING, MAINTENANCE AND ADOPTION....................................... 271

7.1 Planning Process...................................................................................................271

7.2 Plan Update ..........................................................................................................275

7.3 Stakeholder Involvement .......................................................................................277

7.4 Public Involvement................................................................................................279

7.5 Plan Incorporation.................................................................................................280

7.6 Monitoring, Evaluating and Updating the Plan..........................................................282

7.7 Plan Adoption........................................................................................................287 APPENDICES ....................................................................................................... 289 Appendix A: Sample Adoption Resolution.....................................................................289 Appendix B: LHMP Approval Process............................................................................291 Appendix C. Public Outreach Documentation...............................................................293 Appendix D: Survey Results (English) ...........................................................................299 Local Hazard Mitigation Plan Update
5 INTRODUCTION
This document serves as the City of Cathedral City’s Local Hazard Mitigation Plan (LHMP) update for 2025. Hazard mitigation plans are designed to guide communities in reducing the adverse impacts of natural and human-caused hazards by identifying vulnerabilities and implementing strategies to enhance resilience. The preparation and adoption of an LHMP also provides eligibility for Federal Emergency Management Agency (FEMA) grant programs, allowing the City to secure funding for mitigation projects outlined in the plan.

FEMA requires that LHMPs be updated every five (5) years to maintain eligibility for hazard mitigation funding and ensure that the plan reflects current risks, vulnerabilities, and best practices. Cathedral City’s previous LHMP update was completed in 2018. This 2025 update includes significant revisions, aligning with FEMA’s latest guidance.

Structure of the 2025 LHMP Update
The 2025 Cathedral City LHMP Update consists of the following sections:
• An overview of hazard mitigation planning, its purpose, and benefits to the community. • A profile of Cathedral City, detailing its history, climate, demographics, infrastructure, and vulnerable communities.
• An in-depth examination of identified hazards, which were selected in collaboration with City officials and stakeholders. These include:
• Extreme heat
• Drought
• Fire
• Power outage
• Earthquake
• Flooding
• High wind/storms
• Cyberattack/IT disruption
• Infectious disease/pandemic
• Landslide
• Sandstorms
• Transportation-related disruptions
Local Hazard Mitigation Plan Update
6 • An assessment of Cathedral City’s capabilities to mitigate these hazards, including an evaluation of local policies, emergency response resources, land use regulations, and interagency coordination efforts.
• A prioritized list of potential mitigation actions, along with strategies to enhance implementation, funding opportunities, and community engagement. • A description of the LHMP planning process, including stakeholder involvement, public outreach efforts, and integration with existing city and regional plans. • A plan for maintaining and updating the LHMP, ensuring that it remains a living document that continues to support Cathedral City’s resilience goals.

Plan Submission and Approval
The 2025 Cathedral City LHMP Update was submitted to the California Governor’s Office of Emergency Services (Cal OES) and the Federal Emergency Management Agency (FEMA) for approval on [INSERT DATE]. The Cathedral City City Council reviewed and adopted the LHMP on [INSERT DATE], ensuring that the plan remains in effect and that the City retains eligibility for federal hazard mitigation funding programs.

This update represents Cathedral City’s commitment to proactive hazard mitigation planning, ensuring the safety, sustainability, and long-term resilience of the community.

Planning Team
Fire Department
Michael Contreras – Fire Chief
Stakeholder Group
Robert Bradbury -Director of Emergency Services, Agua Caliente Band of Cahuilla Indians Laura James – Chief Executive Officer, Coachella Valley Economic Partnership Angelique Ontiveros – Vice President, Business Development, Desert Arc Gregory Papazian – Emergency Management & Safety Administrator, Coachella Valley Water District
Jacob Green and Associates
Local Hazard Mitigation Plan Update
7 Patrick Marchman, AICP, SCR, Project Manager
Local Hazard Mitigation Plan Update
8 SECTION 1 – HAZARD MITIGATION
Hazard Mitigation Planning
The goal of hazard mitigation is to reduce the frequency and severity of disasters, minimize their impact on communities, and promote resilience and sustainability in the face of future emergencies. This can include measures such as building codes and standards, zoning regulations, evacuation plans, early warning systems, and disaster-resistant infrastructure. By taking a proactive approach to disaster risk reduction, we can help to save lives, reduce the economic impact of disasters, and ensure that communities are better prepared to respond to and recover from emergencies.

Hazard mitigation planning improves a community's ability to effectively respond to natural disasters by establishing plans for maintaining continuity of operations for both government and community entities. The process involves identifying attainable goals to reduce the risk of injury, loss of life, and property damage from hazardous events, and developing strategies and activities to mitigate their effects.

Hazard mitigation planning is intended to be a participatory process that involves government agencies, stakeholders, and the public. The planning process includes scheduled events that encourage participation and ensure that a comprehensive approach is taken to address current and future hazards.

By incorporating a systematic and inclusive approach, the local hazard mitigation plan (LHMP) helps to reduce the community's vulnerability to disasters and promote resilience.

Purpose and Authority
The City of Cathedral City’s 2025 Local Hazard Mitigation Plan (LHMP) outlines the potential natural and human-caused hazards that pose a threat to the citizens, resources, and property in the City. The plan also outlines the city’s objectives and commitment to reducing the risks associated with these hazards.

The focus of this LHMP is on the hazards that pose the greatest risk to the city, as determined through a comprehensive hazard risk assessment and input from local officials. The updated risk assessment will help the city prioritize and update mitigation actions based on the hazards that pose the greatest risk to lives and property.

Local Hazard Mitigation Plan Update
9 FEMA and California Requirements and Compliance
The City of Cathedral City’s risk assessment and hazard mitigation planning efforts adhere to both federal and state regulatory requirements, ensuring compliance with the Disaster Mitigation Act of 2000 (DMA 2000) (Public Law 106-390) and California Government Code §65302(g), which mandates the integration of climate adaptation and hazard mitigation into local planning efforts.

Federal Compliance: FEMA Requirements
The City of Cathedral City’ risk assessment and hazard mitigation planning efforts are guided by federal regulations established under the Disaster Mitigation Act of 2000 (DMA 2000) (Public Law 106-390), which amended the Robert T. Stafford Disaster Relief and Emergency Assistance Act (42 U.S.C. 5121 et seq.). These regulations, codified in Title 44 of the Code of Federal Regulations (CFR) Part 201, require local jurisdictions to develop and maintain a FEMA-approved Local Hazard Mitigation Plan (LHMP) to remain eligible for federal hazard mitigation funding, including grants under the Hazard Mitigation Grant Program (HMGP) and Flood Mitigation Assistance (FMA) Program, among others.

To achieve compliance with 44 CFR §201.6, this plan includes:
• Risk Assessment (§201.6(c)(2)) – A comprehensive analysis of hazard exposure, vulnerability, and potential impacts on people, property, and critical infrastructure. • Mitigation Strategy (§201.6(c)(3)) – A framework of goals, objectives, and prioritized actions designed to reduce long-term risks from identified hazards. • Plan Maintenance Process (§201.6(c)(4)) – A strategy for periodic review, evaluation, and updates to ensure the plan remains current and effective. • Public Involvement (§201.6(b)(1)) – Documentation of community engagement efforts, including outreach to stakeholders, residents, and neighboring jurisdictions. • Integration with Other Plans (§201.6(c)(4)(ii)) – A demonstration of how hazard mitigation efforts align with the General Plan Safety Element, Emergency Operations Plan (EOP), Capital Improvement Plan (CIP), and other local and regional planning mechanisms.

FEMA requires that LHMPs be updated and resubmitted every five years to reflect changes in development patterns, emerging hazard risks, and progress on mitigation actions. This ensures that the City remains eligible for FEMA disaster funding and continues to align with national hazard mitigation priorities, including those outlined in FEMA’s National Mitigation Investment Strategy (NMIS) and the National Risk Index (NRI).

Local Hazard Mitigation Plan Update
10 State of California Compliance: SB 379, SB 1035, and General Plan Integration
In addition to federal requirements, California has established additional hazard mitigation and resilience mandates through legislation that integrates climate adaptation into local planning:
• Senate Bill 379 (SB 379) – Climate Adaptation and Resilience (2015): Requires local jurisdictions to include climate adaptation and vulnerability assessments in the Safety Element of their General Plan, ensuring alignment with the Local Hazard Mitigation Plan (LHMP). • Senate Bill 1035 (SB 1035) – Safety Element Updates (2018): Mandates that the Safety Element be reviewed and updated alongside the LHMP every eight years to account for flooding, wildfires, sea-level rise, and other climate change-related hazards. • California Government Code §65302(g): Requires that cities and counties integrate climate resilience and hazard mitigation into their General Plans, ensuring that disaster risk reduction strategies align with broader land use, housing, infrastructure, and sustainability goals.

Hazard Mitigation Grant Funding
The U.S. Congress passed the Disaster Mitigation Act of 2000 (DMA 2000), which amended the Robert T. Stafford Disaster Relief and Emergency Assistance Act and emphasized the need for state and local governments to closely coordinate their mitigation planning activities. The development of a hazard mitigation plan is a specific eligibility requirement for any local government applying for federal mitigation grant funds. These funds include the Hazard Mitigation Grant Program (HMGP) and Flood Mitigation Assistance (FMA), administered by FEMA.
• Hazard Mitigation Grant Program (HMGP): To qualify for post-disaster mitigation funds, local jurisdictions must have an approved mitigation plan from FEMA. HMGP provides funds to states, territories, Indian tribal governments, local governments, and eligible private non-profit organizations (such as hospitals and special needs populations) following a presidential disaster declaration.
• Flood Mitigation Assistance (FMA): A community must have an approved mitigation plan from FEMA to be eligible for FMA grants to implement flood mitigation, acquisition, or elevation of flood-prone homes. The community must also participate in the National Flood Insurance Program (NFIP) since one of the goals of FMA is to reduce or eliminate NFIP claims.

Local Hazard Mitigation Plan Update
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Local Hazard Mitigation Plan Update
12 SECTION 2 – COMMUNITY PROFILE
This is an overview of the City of Cathedral City with information about the community’s physical setting, history, economy and demographics, current and future land uses, and key infrastructure. The Community Profile establishes the baseline conditions that informs the development of hazard mitigation actions.

2.1 Setting and Location
Cathedral City encompasses a total land area of approximately 21.5 square miles. Situated in the Coachella Valley region of Southern California, it lies roughly 115 miles east of downtown Los Angeles.

The city is bordered by Palm Springs to the west and Rancho Mirage to the east, with the San Jacinto Mountains to the southwest and the Little San Bernardino Mountains to the northeast. Interstate 10 Local Hazard Mitigation Plan Update
13 traverses the northern part of Cathedral City, serving as a vital transportation corridor that enhances regional connectivity. Additionally, major highways such as U.S. Route 111 run through the city, further facilitating access to neighboring communities and the broader metropolitan area.

Cathedral City has a varied topography, with elevations ranging from approximately 165 feet to 1,040 feet above sea level, and an average elevation of about 322 feet (98 meters). The terrain includes both flat areas and gentle slopes, making it suitable for a mix of residential, commercial, and recreational developments. The city’s landscape is characterized by its desert environment, with natural features such as the nearby San Jacinto and Santa Rosa Mountains contributing to its unique geographical setting.

Cathedral City’s transportation infrastructure is well-developed, with Interstate 10 running through the northern part of the city, providing a critical link to other regions. East Palm Canyon Drive (formerly known as State Route 111) also passes through the southern portion of the city, enhancing accessibility to neighboring areas.

2.2 History
The region now known as Cathedral City has been inhabited for at least 2,000 to 3,000 years by the Cahuilla people, whose language belongs to the Uto-Aztecan family. The Cahuilla are traditionally organized into three primary groups: the Mountain Cahuilla, Pass Cahuilla, and Desert Cahuilla. The Coachella Valley area-including present-day Cathedral City-was historically the territory of the Desert Cahuilla, who developed a deep ecological understanding and adaptive strategies suited to the arid desert environment.

Cahuilla villages were established near critical water sources, including Lake Cahuilla, a prehistoric freshwater lake that once filled much of the Coachella Valley. Geological and archaeological evidence suggests the lake’s last major desiccation occurred around 1580 CE. In response, the Cahuilla utilized underground springs and cultivated native desert plants such as mesquite, agave, and the California fan palm (Washingtonia filifera), which served vital roles in diet, construction, and cultural practices.

The Agua Caliente Hot Springs, located within the ancestral territory of the Agua Caliente Band of Cahuilla Indians, held significant cultural and spiritual importance as a site for healing and ceremonial use. The Cahuilla also developed advanced irrigation and resource management systems that enabled Local Hazard Mitigation Plan Update
14 sustainable agriculture in desert conditions, supplemented by hunting and foraging of local fauna and flora.

The first documented European contact in the greater region occurred in 1774, when the Juan Bautista de Anza Expedition passed through parts of Southern California’s inland desert. Although Mission San Gabriel Arcángel was established earlier, in 1771, Spanish influence spread eastward over time. Unlike coastal tribes, the Cahuilla’s geographic remoteness enabled relative autonomy during the mission period, though new trade networks and European diseases nevertheless impacted their population.

Following Mexican independence from Spain in 1821, California became part of Mexico, and much of the Coachella Valley was distributed through land grants or ranchos. Some Cahuilla people were incorporated into ranching systems as laborers, though many continued traditional practices in remote settlements. After the Mexican-American War, California became a U.S. territory in 1848 under the Treaty of Guadalupe Hidalgo.

Increased American settlement in the late 19th century brought pressure on indigenous lands. In 1876, President Ulysses S. Grant established the Agua Caliente Indian Reservation by executive order. The reservation was expanded in 1877, resulting in the “checkerboard” land ownership pattern that remains a defining feature of regional land management today.

In 1855, Colonel Henry Washington of the U.S. Army Corps of Engineers surveyed a canyon in the area and named it Cathedral Canyon due to rock formations that resembled the interior of a cathedral.

The name would later inspire the identity of the developing community.

Formal development of Cathedral City began in 1925 with the establishment of its first subdivision.

The city was officially incorporated on November 16, 1981, and has since grown into a residential, commercial, and cultural center within the Coachella Valley.

As of the 2022 American Community Survey, Cathedral City has a permanent population of 51,967.

According to the 2024 Greater Palm Springs Economic Report (CVEP, citing ESRI Business Analyst and U.S. Census data), Cathedral City ranks as the eighth largest city in Riverside County by population and the fourth highest in taxable retail sales in the Coachella Valley (2023).

Strategically located approximately 110 miles east of Los Angeles and 115 miles northeast of San Diego, Cathedral City shares borders with Palm Springs to the west and Rancho Mirage to the east. The city’s Local Hazard Mitigation Plan Update
15 growth has been strongly influenced by its proximity to major transportation corridors, particularly Interstate 10, which supports regional access and economic connectivity.

Cathedral City has demonstrated a commitment to revitalization and economic development, with targeted investments in downtown redevelopment, green space expansion, and public infrastructure.

These efforts have supported the city’s business environment and quality of life. Signature community events-such as the Cathedral City Hot Air Balloon Festival (celebrating its 10th year in 2024), the Taste of Jalisco Festival, and LGBTQ+ Days-underscore the city’s cultural vibrancy and inclusive civic identity.

The Agua Caliente Band of Cahuilla Indians continues to play a vital role in the region. The Tribe’s reservation encompasses approximately 31,610 acres, including parts of Cathedral City, Palm Springs, and Rancho Mirage, as well as unincorporated areas of Riverside County. The Tribe partners with municipalities across the region to coordinate on land use, infrastructure, and cultural preservation, sustaining both economic and heritage priorities across its ancestral lands.

2.3 Climate
Cathedral City is located in the Coachella Valley, approximately 115 miles inland from the Pacific Ocean, and experiences a hot desert climate (BWh) under the Köppen climate classification system.

The city lies within the Colorado Subdivision of the Sonoran Desert, located in the northwestern portion of one of North America’s most arid and biologically diverse desert regions. This area is characterized as a hot and dry subtropical desert, with extreme summer temperatures, high solar exposure, and minimal annual precipitation.

This climate is marked by long, extremely hot summers and mild, brief winters, with very limited precipitation throughout the year. The city’s summers bring some of the hottest temperatures in California, with average high temperatures reaching 107°F (42°C) in July and August, while peak summer heatwaves frequently exceed 115°F (46°C). Nighttime lows during these extreme heat events can remain above 80°F (27°C), further intensifying the risk of heat-related illnesses and power grid stress. Winters, in contrast, are much milder, with average high temperatures of approximately 71°F (22°C) in January, and low temperatures ranging between 44°F (7°C) and 50°F (10°C).

Cathedral City also has one of the highest annual sunshine rates in the United States, averaging approximately 348 sunny days per year, making it one of the sunniest locations in the country.

Local Hazard Mitigation Plan Update
16 Annual precipitation in Cathedral City is very limited, with the city receiving an average of only 5 inches (127 mm) of rainfall per year, making it one of the driest cities in Southern California. Rainfall is highly seasonal, occurring almost exclusively between November and March, with January being the wettest month, though precipitation levels even during this period are typically below an inch per month on average. Summers are almost entirely dry, though occasional monsoonal moisture in late summer can bring brief but intense thunderstorms, sometimes leading to localized flash flooding.

While Cathedral City does not experience the marine layer clouds that are common in coastal Southern California, its proximity to the San Jacinto and Santa Rosa Mountains does allow for occasional cool evening breezes, which can provide some relief during the extreme summer heat. Additionally, the city is periodically affected by Santa Ana winds, which typically occur in fall and winter. These warm, dry winds originate from inland areas, raising temperatures while significantly lowering humidity, which can exacerbate wildfire risks across the region.

Despite the city’s arid environment, localized flash flooding remains a hazard, particularly during rare but intense storms. Heavy rainfall from monsoonal moisture or atmospheric disturbances can overwhelm desert soils and drainage systems, leading to localized flooding. Buildings in 40 out of 51 census tracts in Cathedral City are at significant risk of surface (pluvial) and riverine (fluvial) flooding.

Approximately 71% of buildings in Cathedral City are at some level of risk from flooding, including both surface (pluvial) flooding and riverine (fluvial) flooding.

Month Avg High (°F) Avg Low (°F)
January 71 45
February 75 48
March 81 52
April 88 58
May 95 65
June 104 73
July 108 81
August 107 80
September 102 74
October 91 63
November 78 51
December 69 44
Month Avg Precipitation (inches)
January 1.18
February 1.09
Local Hazard Mitigation Plan Update
17 Month Avg Precipitation (inches)
March 0.63
April 0.15
May 0.03
June 0.01
July 0.18
August 0.41
September 0.22
October 0.24
November 0.31
December 0.79
Average monthly high and low temperatures and precipitation for Cathedral City, CA, based on 30-year climate normals (1991–2020) from the NOAA National Centers for Environmental Information (NCEI) and validated with data from Weather Spark and U.S. Climate Data for nearby Palm Springs:

Local Hazard Mitigation Plan Update
18 2.4 Climate Change
Cathedral City is projected to experience significant increases in temperature due to climate change.

According to the Fifth National Climate Assessment (2023), average annual temperatures across California are expected to rise by 5°F to 8°F (2.8°C to 4.4°C) by mid-century relative to historical baselines. Given that Cathedral City already experiences extreme summer temperatures, often exceeding 105°F (40°C), this warming trend is expected to result in more frequent and prolonged heatwaves, with the number of days surpassing 110°F (43°C) increasing substantially. By 2050, projections indicate that Cathedral City could experience an average of 32 days per year above 111.9°F, compared to just 7 days annually in 1990.

These extreme heat conditions pose serious public health risks, especially for vulnerable populations such as the elderly, children, and those with underlying medical conditions. The urban heat island effect-driven by extensive impervious surfaces, minimal urban canopy, and heat-retaining materialsfurther intensifies ambient temperatures. Elevated temperatures also drive higher electricity demand for air conditioning, increasing strain on the power grid. A prolonged power outage during extreme heat events could result in severe health and safety consequences.

Climate models also predict increased variability in rainfall, with greater extremes at both ends of the precipitation spectrum. While Cathedral City currently averages approximately 5 inches (127 mm) of rainfall annually-mostly between November and March-future precipitation is expected to occur in more concentrated and intense bursts. Tropical Storm Hilary in August 2023 exemplified this trend.

Although Cathedral City received roughly 3.3 inches of rain over a 24-hour period, local flooding was largely driven by a mudslide over 25 miles away in the San Bernardino Mountains, which clogged the Whitewater River channel and overwhelmed downstream infrastructure.

Cathedral City’s flood risk is heightened by its desert soil composition, which is often compacted and hydrophobic, reducing infiltration and increasing runoff during heavy rain events. According to the City’s Safety Element, the projected 100-year 24-hour storm for the planning area is 5.42 inches of rain, emphasizing the importance of resilient stormwater infrastructure. Historic events, such as the 1939 storm that dropped 6.45 inches over Indio in 6 hours, and the 1976 storm caused by Tropical Storm Kathleen, which brought 6.81 inches to valley areas and over 14 inches to adjacent mountains, further illustrate the region’s exposure to rare but intense storm systems.

While total annual precipitation may not change significantly, the frequency and duration of droughts are expected to increase. Since 2000, the Whitewater River watershed has experienced some level of Local Hazard Mitigation Plan Update
19 drought in 80% of monitored weeks, with 17% classified as Extreme or Exceptional Drought.

Simultaneously, inconsistent snowpack from the Sierra Nevada and Rocky Mountain ranges, major sources of imported water for Southern California, pose long-term challenges to water security and may necessitate expanded conservation, new supply infrastructure, and drought resilience investments Rising temperatures are also expected to worsen local air quality, especially through increased formation of ground-level ozone, which is exacerbated by heat and sunlight. Cathedral City, which already faces air quality challenges from regional pollution sources, may see an increase in respiratory and cardiovascular ailments such as asthma and bronchitis.

Though Cathedral City is not located within a Very High Fire Hazard Severity Zone, climate change is projected to increase the frequency and intensity of wildfires across California. Smoke from these fires can travel long distances, and the Coachella Valley is increasingly affected by degraded air quality from fine particulate matter (PM2.5) during regional fire events, posing a secondary climate-related health hazard to the city’s residents.

2.5 Demographics
Cathedral City experienced sustained population growth throughout the second half of the 20th century, driven by regional expansion across the Coachella Valley and the city's relative affordability compared to neighboring resort communities such as Palm Springs and Rancho Mirage. Residential development accelerated in the 1990s and early 2000s in response to growing housing demand across Southern California. However, the pace of growth began to slow during the 2010s due to rising housing costs, economic shifts, and broader demographic trends.

Between 2000 and 2023, Cathedral City’s average annual population growth was approximately 0.3%, reflecting a more modest increase than in previous decades. The COVID-19 pandemic and related economic disruptions between 2020 and 2022 contributed to a temporary decline in population. During that period, Cathedral City experienced a population decrease of approximately 2.8%, consistent with broader regional trends, as many residents relocated to more affordable inland areas or out of state.

According to the 2024 Greater Palm Springs Economic Report (CVEP, citing ESRI Business Analyst and California DOF), Cathedral City’s estimated population in 2024 is 52,494, down slightly from the 2020 Census count of 54,676 but consistent with the state’s post-pandemic recovery projections.

Local Hazard Mitigation Plan Update
20 Population and Racial/Ethnic Composition
Cathedral City is among the most ethnically diverse cities in the Coachella Valley. According to the 2022 ACS 5-Year Estimates and the CVEP 2024 report, Hispanic or Latino residents represent the majority of the population. The city’s population profile is summarized below:

Population Overview (2024 Estimate)
• Total Population: 52,494
• Sex:
• Male: 51.6%
• Female: 48.4%
• Age Distribution:
• Under 18 years: 20.2%
• 65 years and over: 18.0%
Race and Hispanic Origin
• White (Non-Hispanic): 29.7%
• Hispanic or Latino (of any race): 58.9%
• Black or African American: 1.9%
• American Indian and Alaska Native: 2.0%
• Asian: 6.9%
• Native Hawaiian or Other Pacific Islander: 0.3%
• Two or More Races: 0.6%
Educational Attainment (Age 25 and Older)
• High school graduate or higher: 80.9%
• No high school diploma: 17.0%
• High school or GED only: 30.0%
• Bachelor’s degree or higher: 28.0%
• Bachelor’s degree or higher (confirmed in ACS): 25.8% Income and Economy
As of 2024, Cathedral City’s estimated median household income is $65,462, while the per capita income stands at $33,408, based on ESRI Business Analyst and ACS 2022 data.

Local Hazard Mitigation Plan Update
21 Historically, Cathedral City's economy has been closely tied to tourism, hospitality, and service-sector employment, owing to its proximity to Palm Springs and other resort destinations. In recent years, however, the city has sought to diversify its economic base by promoting sectors such as:
• Retail trade and logistics
• Construction and real estate development
• Renewable energy and clean-tech investments

2.6 Housing and Development
Incorporated in 1981, Cathedral City’s early housing stock reflected the region’s expansion as a residential community supporting nearby resort hubs like Palm Springs. By the mid-20th century, development primarily featured modest single-family ranch-style homes, catering to working-class families drawn to the affordability of the Coachella Valley and the employment base in service and hospitality industries. These homes often included open floor plans and outdoor features well-suited to the desert climate.

Substantial residential expansion occurred during the 1980s and 1990s, during which Cathedral City emerged as a major population center within the valley. Housing types diversified to include multifamily developments-such as duplexes, apartments, and townhomes-driven by demand for more affordable and varied housing options. By 2000, the city’s population exceeded 42,000, and residential development accelerated to meet demand.

By 2020, Cathedral City had an estimated 20,000 housing units, encompassing a mix of single-family homes, condominiums, and rental properties. Its relative housing affordability compared to neighboring cities such as Palm Springs made it increasingly attractive for middle-income families, retirees, and seasonal residents.

Current Housing Market Trends (2024–2025)
As of early 2025, Cathedral City’s housing market reflects broader Southern California trends: strong post-pandemic price escalation, constrained supply, and affordability concerns. According to the TownCA February 2025 Desert Housing Report, the median home price (MHP) in Cathedral City reached $528,000, a sharp increase from prior years and a 51% increase in value since 2020, per the Zillow Home Value Index (ZHVI) data cited in the CVEP 2024 Economic Report.

Local Hazard Mitigation Plan Update
22 Despite these gains, Cathedral City remains more affordable than many Coachella Valley citiesespecially Palm Desert, Rancho Mirage, and Indian Wells. This price advantage has continued to support demand from first-time buyers and moderate-income households. However, rising costs have introduced new affordability challenges.

Rental Market and Tenure
The rental market remains strong, supported by proximity to employment centers, retail amenities, and tourism. As of early 2024, the average rent for a one-bedroom apartment in Cathedral City is approximately $1,450/month, maintaining the city’s status as one of the more accessible rental markets in the valley. Owner-occupancy has modestly increased in recent years. According to ACS 2022 5-Year Estimates, approximately 58% of housing units are owner-occupied, while 42% are renter-occupied.

Local Hazard Mitigation Plan Update
23 Local Hazard Mitigation Plan Update
24 Housing Characteristics and Affordability
Cathedral City’s residential areas offer a blend of mid-century subdivisions and newer master-planned communities, many of which cater to retirees, snowbirds, and second-home buyers. Drought-tolerant landscaping and energy-efficient retrofits are common features, aligning with regional conservation goals.

However, rising housing costs have increased the financial burden for both renters and homeowners.

The median selected monthly owner cost (SMOC) with a mortgage is estimated at $2,150, while the median gross rent is approximately $1,450, as reported by the ACS and corroborated in local housing reports.

Seasonal Housing and Vacancy
Cathedral City maintains a significant share of seasonal and vacation housing, a reflection of its role as a second-home destination. As of 2019, approximately 20.3% of housing units were classified as vacant, with most designated for seasonal, recreational, or occasional use, based on ACS data.

Housing and Occupancy Data – 2023 Estimates
Metric Value
Total households 18,250
Owner-occupied housing rate 58%
Median home price (2025) $528,000
Median selected monthly owner costs $2,150
Median gross rent $1,450
Persons per household 3.2
Local Hazard Mitigation Plan Update
25 2.7 Economy
Cathedral City maintains a diverse and evolving economy, shaped by its role as a residential and service-oriented community within the Coachella Valley. While not a major tourism destination in the same way as Palm Springs, Cathedral City’s economy is influenced by regional tourism through its sizable hospitality and service workforce. The city’s proximity to major resort destinations contributes to job creation in food service, accommodations, entertainment, and support services.

Historically, Cathedral City's economic foundation was rooted in retail, hospitality, and residential development. Over time, the city has broadened its economic base to include healthcare, construction, real estate, and-more recently-logistics and light manufacturing.

The expansion of the Palm Springs International Airport in 2024 positions Cathedral City for potential inclusion in a regional Foreign Trade Zone (FTZ). This designation could support logistics, warehousing, and light manufacturing activities, particularly for companies seeking tariff reductions and streamlined customs processes. Development interest in last-mile delivery and regional distribution centers has increased, spurred by e-commerce growth following the COVID-19 pandemic.

Tourism and Hospitality
Tourism and hospitality continue to influence Cathedral City's economy, but primarily through employment, not as a destination driver. The city supports a workforce employed in nearby resort hubs and contributes to the region's service economy. Local events such as the Cathedral City International Hot Air Balloon Festival, LGBTQ+ Days, and venues such as the Mary Pickford Theatre, CVRep Theater, and the Perez Art District provide important cultural and recreational amenities that enhance quality of life and attract visitors, particularly for arts and entertainment.

As of 2024, approximately 3,800 workers are employed in accommodation and food services and arts, entertainment, and recreation, accounting for roughly 15.9% of the local workforce. While Cathedral City does not function as a core tourism hub, this sector remains an essential part of its employment landscape.

Retail and Commercial Services
Retail is a pillar of Cathedral City’s economy, particularly in terms of tax revenue generation. The city serves as a commercial hub for eastern Coachella Valley communities, anchored by regional shopping centers along East Palm Canyon Drive, Ramon Road, and the Cathedral City Auto Center-one of the largest automotive sales clusters in the valley.

Local Hazard Mitigation Plan Update
26 Auto sales, in particular, are a cornerstone of the city’s retail tax base. Recognizing the competitive nature of the auto industry, the city is conducting a SWOT (Strengths, Weaknesses, Opportunities, Threats) analysis in collaboration with local dealerships to bolster sector resilience amid regional and online competition.

In 2024, the retail sector employed approximately 2,700 workers, accounting for 11.3% of the city’s total employment. The city continues to pursue commercial revitalization efforts, especially in the Downtown Core and East Palm Canyon corridor, through capital improvement projects and retail diversification strategies.

Healthcare and Social Services
The healthcare and social services sector is among the fastest-growing in Cathedral City. A combination of population aging and regional healthcare investment has led to the expansion of medical offices, outpatient clinics, and senior care facilities.

Major healthcare anchors in the surrounding area include Eisenhower Health (Rancho Mirage), Desert Regional Medical Center (Palm Springs), John F. Kennedy Memorial Hospital (Indio), and services coordinated through the Desert Healthcare District.

As of 2024, approximately 3,300 workers are employed in the healthcare and social assistance sector, representing 13.8% of the workforce. Continued growth is anticipated due to demographic trends and regional healthcare demand.

Construction and Real Estate
The construction sector plays a central role in Cathedral City’s economy, driven by housing development, commercial expansion, and infrastructure investment. Housing demand from full-time residents, retirees, and seasonal homeowners-attracted by relatively lower prices compared to Palm Springs or Rancho Mirage-has sustained growth in both the residential and commercial building sectors.

As of 2024, approximately 2,100 workers are employed in construction, accounting for 8.8% of local jobs. The real estate sector-including leasing, property management, and brokerage-continues to benefit from demand across both rental and owner-occupied housing markets.

Logistics, Warehousing, and Manufacturing
Local Hazard Mitigation Plan Update
27 Post-pandemic shifts in consumer behavior have increased demand for logistics and distribution facilities, positioning Cathedral City to attract investment in last-mile delivery, warehousing, and light industrial development.

While still a smaller portion of the total economy, the transportation, warehousing, and utilities sector employs around 1,100 workers (4.6%), and manufacturing employs 1,400 workers (5.9%) as of 2024.

These sectors are expected to grow, especially if Cathedral City secures an FTZ designation and further develops its industrial land base.

Industry Breakdown: Cathedral City Economy (2024)
Industry Number of Jobs Percent of Workforce (%)
Accommodation and Food Services 3,725 15.6%
Retail Trade 2,700 11.3%
Educational Services, and Healthcare and Social Assistance 3,300 13.8% Construction 2,100 8.8%
Manufacturing 1,400 5.9%
Wholesale Trade 750 3.1%
Transportation and Warehousing, and Utilities 1,100 4.6% Information 300 1.3%
Finance and Insurance, and Real Estate and Rental Leasing 1,200 5.0% Professional, Scientific, and Management Services 1,500 6.3% Arts, Entertainment, and Recreation 3,800 15.9%
Other Services (except Public Administration) 1,300 5.4% Public Administration 950 4.0%

2.8 Infrastructure
Electricity and Natural Gas
Electricity service in Cathedral City is provided by Southern California Edison (SCE), which maintains a regional power distribution network for the Coachella Valley. This includes four substations and transmission infrastructure along major corridors such as Date Palm Drive, Landau Boulevard, and Dinah Shore Drive. The system features both overhead and underground lines to serve homes, businesses, and public facilities. SCE conducts routine five- and ten-year load forecasting to identify grid reinforcement and service expansion needs.

Natural gas service is provided by Southern California Gas Company (SoCalGas). High-pressure transmission pipelines enter the region north of Interstate 10, where gas is distributed via medium- Local Hazard Mitigation Plan Update
28 pressure lines throughout the city. Primary gas corridors include Vista Chino, Date Palm Drive, Varner Road, East Palm Canyon Drive, and Mountain View Road. Natural gas supports residential, commercial, and industrial energy needs across Cathedral City.

Water Infrastructure
Water service in Cathedral City is delivered by two special districts: the Coachella Valley Water District (CVWD) and the Desert Water Agency (DWA), depending on the service area. These agencies, not the City, are responsible for water supply infrastructure investments, operations, and long-term planning.

Water is sourced from the Coachella Valley Groundwater Basin, which is replenished with imported water from the Colorado River (via the Coachella Canal and Colorado River Aqueduct) and from the State Water Project (through a water exchange agreement with Metropolitan Water District). Each agency maintains pipelines, wells, reservoirs, and booster stations to deliver water reliably. Major transmission lines follow key corridors such as Dinah Shore Drive, Ramon Road, and East Palm Canyon Drive.

Water conservation is a shared priority, with both CVWD and DWA offering rebates for droughttolerant landscaping, smart irrigation systems, and recycled water systems. Groundwater replenishment and recycled water distribution-particularly for non-potable uses like golf courses-are central to regional water sustainability goals.

Wastewater Infrastructure
Wastewater collection is managed by CVWD or DWA, based on service area jurisdiction. CVWD operates Wastewater Reclamation Plant No. 10 (WRP-10) in Palm Desert, which treats effluent from Cathedral City and recycles it for non-potable irrigation. Sewer infrastructure includes trunk lines between 4 and 24 inches in diameter, routed along major roadways.

The Cove Improvement District Sewer and Street Project, launched in 2008, connected hundreds of formerly unsewered homes in the city’s Cove area to the municipal system, replacing aging septic systems. The City enforces connection mandates for all new development.

Road and Highway Network
Cathedral City’s transportation infrastructure is anchored by Interstate 10 and East Palm Canyon Drive (former State Route 111). I-10 interchanges at Date Palm Drive, Bob Hope Drive, and Palm Drive serve Local Hazard Mitigation Plan Update
29 regional and long-haul traffic. Major east-west arterials such as Ramon Road, Dinah Shore Drive, and Gerald Ford Drive support intracity mobility.

The Varner Road corridor, north of I-10, is a critical east-west bypass route vulnerable to flooding and blowsand. The City is actively collaborating with the Coachella Valley Association of Governments (CVAG) to study and improve this corridor, which may function as an alternative route during I-10 closures.

Public Transit
Public transportation is provided by SunLine Transit Agency, which operates regional bus service across the valley. SunLine has introduced hydrogen and battery-electric buses, making Cathedral City part of one of the nation’s cleanest transit fleets. Route connections include Palm Springs, Rancho Mirage, and Indio.

To support active transportation, the City continues to invest in bike lanes, sidewalk upgrades, and safe crossings, particularly along East Palm Canyon Drive.

Stormwater and Flood Control
Cathedral City’s desert setting makes it highly vulnerable to flash flooding. The City’s stormwater infrastructure includes retention basins, storm drains, levees, and natural washes. Flood control investments are primarily led by CVWD and the Riverside County Flood Control and Water Conservation District (RCFCD).
• Eagle Canyon Dam (completed 2015) mitigates upstream flooding that historically affected East Palm Canyon Drive.
• The Cathedral Canyon Wash system conveys floodwaters into the Whitewater River Channel, the region’s principal drainage corridor.
• The Cathedral City Storm Drain Master Plan guides infrastructure upgrades with attention to climate resilience.

Localized stormwater management challenges persist, especially along Dinah Shore Drive and Gerald Ford Drive, where historic road depressions contribute to ponding during storm events.

Following Tropical Storm Hilary in 2023, the Federal Highway Administration awarded the City a grant to reconstruct Date Palm Drive between Vista Chino and Tachevah, which includes stormwater mitigation at the Los Gatos Drive intersection, a chronic flooding site. The City is also working with Local Hazard Mitigation Plan Update
30 CVAG on the Varner Road ByPass Study, evaluating mitigation measures needed to ensure Varner Road remains open during flooding and blowsand events. Improvements to Date Palm Drive (north of I-10) are also underway via a separate cooperative design agreement.

Public comments during the LHMP update process identified areas that regularly flood—such as Date Palm Drive near Los Gatos Road and DaVall Road near Century Park—as potential candidates for wetland restoration or conversion to functional green infrastructure. These measures could offer cost-effective, low-maintenance alternatives to traditional infrastructure while delivering co-benefits like carbon sequestration, habitat creation, and community cooling.

2.9 Historically Vulnerable Populations
Low-Income Residents
Major Hazards: Extreme Heat, Drought, Earthquake, High Wind/Storms Approximately 15.6% of Cathedral City’s population lives below the poverty line. Limited financial capacity reduces access to preparedness resources, insurance, and safe shelter. Many low-income households reside in older housing stock that may lack insulation or cooling systems, heightening exposure to extreme heat and seismic risk.

Elderly Individuals
Major Hazards: Earthquake, Power Outages, Infectious Disease Approximately 18.4% of Cathedral City’s population is over 65, including:\ • 12.1% aged 65–74
• 9.2% aged 75+
Older adults are at increased risk during heatwaves, blackouts, and earthquakes due to mobility limitations, medical dependencies, and social isolation. Emergency planning must prioritize power continuity, cooling centers, and proactive wellness checks.

People with Disabilities
Major Hazards: Earthquake, Power Outages
Local Hazard Mitigation Plan Update
31 Roughly 12.8% of residents have a disability, encompassing physical, sensory, and cognitive impairments. Disasters can disrupt mobility aids, medical devices, and communications systems.

Accessible shelters and inclusive alert systems are critical.

Minority Communities
Major Hazards: Earthquake, Fire, Power Outage
Hispanic or Latino residents make up 58.9% of the population (CVEP). Language barriers, limited healthcare access, and economic disparities increase disaster vulnerability. Multilingual alerts and culturally competent outreach are essential.

Unhoused Populations
Major Hazards: Extreme Heat, Drought, Fire, High Wind/Storms, Infectious Disease/Pandemic
As of the latest Point-in-Time Count, Cathedral City has 82 unhoused individuals, a 78% increase since 2018. Exposure, limited medical access, and proximity to transportation corridors or fire-prone open spaces heighten risks.

The Cathedral City Police Department Homeless Liaison Program partners with a Riverside County public health worker to provide outreach and coordinate with emergency services during extreme events.

Social Vulnerability Index
The Social Vulnerability Index (SOVI) is a critical tool in assessing community resilience to hazards.

Developed by the Centers for Disease Control and Prevention (CDC) and the Agency for Toxic Substances and Disease Registry (ATSDR), the SOVI ranks census tracts based on 15 social factors contributing to vulnerability. These include income, age, disability status, housing type, transportation access, and minority status. The higher the index score (ranging from 0 to 1), the greater the vulnerability of a community.

Local Hazard Mitigation Plan Update
32 Population
Group
Soi
Score
(0-1)
Description of Vulnerability
Low-Income
Residents 0.81
Many residents live in older housing that lacks resilience to seismic events, extreme heat, and flooding. Limited financial resources reduce their ability to evacuate or access recovery services.

Elderly
Individuals
(65+)

0.84 Many elderly residents have mobility and health challenges that limit their ability to evacuate during disasters. They are also more likely to rely on power-dependent medical devices, increasing vulnerability to power outages. Social isolation exacerbates risks during emergencies.

People with
Disabilities 0.85
Disabilities affecting mobility, sensory, or cognitive function can hinder emergency response, evacuation, and medical access. Power outages and transportation disruptions further heighten risks.

Minority
Communities 0.79
Many minority communities experience language barriers and economic disadvantages, impacting disaster response and recovery. Targeted outreach and multilingual emergency resources are essential to reduce these disparities.

Unhoused
Populations 0.90
Homeless individuals face extreme risks from heat, fire, storms, and poor air quality.

Many lack access to emergency shelter, medical care, and disaster communication services.

SECTION 3 – HAZARD IDENTIFICATION AND RISK

ASSESSMENT
Element B: Risk Assessment Requirements
B1. Does the plan include a description of the type, location and extent of all natural hazards that can affect the jurisdiction? Does the plan also include information on previous occurrences of hazard events and on the probability of future hazard events? (Requirement 44 CFR § 201.6(c)(2)(i))

3.1 Introduction
Purpose of the Risk Assessment
The risk assessment process aligns with federal and state regulatory requirements, including the Disaster Mitigation Act of 2000 (DMA 2000) (44 CFR §201.6), which mandates that local jurisdictions conduct a comprehensive, forward-looking risk assessment to maintain eligibility for FEMA’s Hazard Local Hazard Mitigation Plan Update
33 Mitigation Assistance (HMA) grant programs. Additionally, the assessment incorporates climate adaptation planning requirements outlined in FEMA’s 2023 Local Mitigation Planning Policy Guide and California Government Code §65302(g), ensuring integration with state-mandated safety and resilience planning.

From a technical perspective, the risk assessment evaluates hazard probability, severity, and cascading impacts using a multi-layered analytical framework that integrates historical disaster data and FEMA disaster declarations as well as climate projections and future risk modeling.

FEMA Requirements and Compliance
The City of Cathedral City’s risk assessment and hazard mitigation planning efforts are guided by federal regulations established under the Disaster Mitigation Act of 2000 (DMA 2000) (Public Law 106- 390), which amended the Robert T. Stafford Disaster Relief and Emergency Assistance Act (42 U.S.C. 5121 et seq.). These regulations, codified in Title 44 of the Code of Federal Regulations (CFR) Part 201, require local jurisdictions to develop and maintain a FEMA-approved Local Hazard Mitigation Plan (LHMP) to remain eligible for federal hazard mitigation funding, including grants under the Hazard Mitigation Grant Program (HMGP) and Flood Mitigation Assistance (FMA) Program, among others.

To achieve compliance with 44 CFR §201.6, this plan includes:
• A Risk Assessment (§201.6(c)(2)) – A comprehensive analysis of hazard exposure, vulnerability, and potential impacts on people, property, and critical infrastructure.

Relationship to Other Planning Elements
Hazard identification and risk assessment is a foundational component of the City of Cathedral City’s comprehensive planning framework, ensuring that hazard mitigation strategies are fully integrated into broader land use planning, emergency management, infrastructure investment, environmental sustainability, and climate adaptation efforts. This alignment strengthens the City’s ability to reduce disaster risks, enhance community resilience, and optimize access to federal and state funding opportunities.

Federal and state regulations, including FEMA’s Local Hazard Mitigation Plan (LHMP) requirements (44 CFR §201.6) and California Government Code §65302(g) (as amended by SB 379 and SB 1035), require jurisdictions to incorporate hazard mitigation and climate adaptation strategies into their General Plan Safety Element and other municipal planning documents. By fostering consistency across planning efforts, the City proactively integrates risk reduction principles into growth and development decisions, ensuring a safer, more resilient future.

Local Hazard Mitigation Plan Update
34 Integration with Local and Regional Plans
The City’s risk assessment is closely coordinated with the following local and regional planning efforts, ensuring a holistic, cross-sectoral approach to hazard mitigation and climate resilience:

General Plan Safety Element
• Mandated by SB 379 and SB 1035, the Safety Element incorporates hazard risk assessments, climate adaptation strategies, and emergency preparedness measures to reduce vulnerabilities in the built environment.
• Regular updates ensure that the Safety Element remains aligned with the LHMP, reflecting evolving risks such as wildfire, flooding, seismic activity, and extreme heat. • Integration with land use planning promotes smart growth strategies, minimizing exposure to high-risk areas.
• In coordination with CVAG, Riverside County Flood Control and Water Conservation District, and neighboring jurisdictions such as Palm Springs, Rancho Mirage, and Desert Hot Springs, Cathedral City is participating in regional roadway flooding and blowsand hazard mitigation studies. This collaboration has resulted in the initiation of three regional roadway improvement projects designed to mitigate 100-year flood event–related roadway shutdowns. • The City is an active participant in the CVAG Interstate 10 Bypass Study, which is assessing hazards and mitigation requirements for an alternative cross-valley (west–east) transportation route in the event of a prolonged I-10 closure.

Emergency Operations Plan (EOP)
• The City’s EOP establishes operational protocols for disaster response and recovery, ensuring effective coordination among Cathedral City departments, Riverside County Emergency Management Department, CVAG, California Office of Emergency Services (Cal OES), and local nonprofit and community-based organizations.
• The LHMP risk assessment informs:
• Evacuation planning for at-risk populations,
• Resource allocation for emergency services, and
Local Hazard Mitigation Plan Update
35 • Emergency communication strategies to enhance public safety and ensure continuity of services.

Capital Improvement Plan (CIP)
• The CIP prioritizes critical infrastructure investments that reduce vulnerability to identified hazards, with risk-informed selection criteria. Investments include:
• Stormwater management and retention basin upgrades,
• Seismic retrofits of public safety facilities and city-owned buildings, • Roadway reconstruction projects that incorporate resilience to flooding and blowsand, • Microgrid readiness and backup power for emergency shelters and critical infrastructure.
• Projects are implemented in coordination with CVWD, RCFCD, SCE, and adjacent cities, particularly where infrastructure spans jurisdictional boundaries.

Zoning and Building Codes
• The City’s Code of Ordinances incorporates hazard mitigation and resilience into land use, zoning, and construction standards.
• The risk assessment directly informs:
• Seismic design standards for new and substantially improved structures, • Wildland-urban interface (WUI) building requirements and fire-resistance standards to reduce exposure to wildfire and structure fires.
• Cathedral City is actively working on a comprehensive update to its zoning code, scheduled for completion in 2026, to align land use policy with climate and hazard risk considerations. • The City currently uses the 2022 California Building Code (CBC) and is preparing for adoption of the 2025 CBC, which will go into effect in 2026, to ensure building practices reflect the latest seismic, energy, and fire safety requirements.

Summary of Interagency Coordination
Cathedral City integrates LHMP priorities through formal collaboration with:
• Coachella Valley Association of Governments (CVAG) – flood control, active transportation, and I-10 bypass planning,
• Riverside County Emergency Management Department – emergency preparedness and incident coordination,
Local Hazard Mitigation Plan Update
36 • Riverside County Flood Control and Water Conservation District (RCFCD) – regional stormwater planning and infrastructure investment,
• Coachella Valley Water District (CVWD) and Desert Water Agency (DWA) – water and wastewater resilience strategies,
• Southern California Edison (SCE) and SoCalGas – energy reliability and hazard mitigation, • Neighboring cities (Palm Springs, Rancho Mirage, Desert Hot Springs) – mutual aid, crossjurisdictional infrastructure planning, and shared mitigation priorities, • Cal OES – for funding, technical assistance, and plan integration guidance at the state level.

Methodology and Data Sources
The risk assessment for Cathedral City utilizes a comprehensive, multi-layered approach that integrates historical disaster data, geospatial analysis, probabilistic risk modeling, and climate projections. This methodology ensures that mitigation planning is data-driven, forward-looking, and aligned with evolving hazard conditions specific to the Coachella Valley.

The risk assessment follows FEMA’s Local Hazard Mitigation Plan (LHMP) requirements (44 CFR §201.6) and incorporates California-specific regulations, including:
• California Government Code §65302(g) (SB 379, SB 1035): Requires jurisdictions to integrate hazard mitigation and climate adaptation strategies into the General Plan Safety Element. • California Adaptation Planning Guide (2020): Developed by Cal OES to provide a framework for assessing climate vulnerabilities and future hazard risks. • Riverside County Multi-Jurisdictional Hazard Mitigation Plan (MJLHMP) (2023): Provides county-wide risk assessments for hazards such as wildfire, flooding, drought, and extreme heat. • 2023 California State Hazard Mitigation Plan (SHMP): Offers statewide hazard profiles and risk assessments, including projections for wildfire, flooding, drought, extreme heat, earthquakes, and other climate-driven hazards.

By integrating local, regional, and state-level risk assessment frameworks, Cathedral City ensures that mitigation planning is comprehensive, equity-focused, and aligned with best practices in climate resilience.

Historic Disaster Declarations
Given the size and geographic diversity of Riverside County, this LHMP will not provide a list of all disaster declarations for the county. Historic disaster declarations may be found by specific hazard.

Local Hazard Mitigation Plan Update
37 Consideration of Future Climate Conditions and Changing Risks Recognizing the increasing frequency and severity of climate-related hazards, the HIRA incorporates scientific projections from regional, state, and national climate assessments, ensuring that mitigation strategies remain adaptive to future conditions.

Key climate risk projections include:
• Riverside County Climate Vulnerability Assessment (2023): Projects:
• A significant increase in extreme heat events, with Cathedral City experiencing over 30 days per year above 111°F (44°C) by 2050.
• Rising wildfire risk, with 30% of all Cathedral City properties facing some level of exposure over the next 30 years.
• Greater intensity of inland flooding due to sporadic heavy rainfall events and constrained stormwater infrastructure.
• California’s Fourth Climate Change Assessment (2018): Provides downscaled climate modeling for temperature rise, drought severity, and extreme weather variability through 2100. • First Street Foundation’s Climate Risk Data (2024): Includes probabilistic modeling for flooding, extreme heat, and air quality deterioration, supporting local infrastructure resilience planning.
• Cathedral City General Plan and Safety Element (2024 Update): Aligns land use policies with projected wildfire, earthquake, and flood risk exposure, ensuring compliance with SB 379 and SB 1035.
• Southern California Association of Governments (SCAG) Regional Climate Adaptation Framework (2020): Establishes regional resilience strategies for:
• Drought mitigation.
• Transportation adaptation.
• Energy grid reliability.
• Coachella Valley Association of Governments
• Flooding & Blowsand Risk Assessment and Improvement Plan for Western Coachella Valley: identifies hazards and risk and provides mitigation measures within the region and the city.
• CVAG Varner Road I-10 Bypass Feasibility Study: identifies hazards and risk and provides mitigation measures within the region and the city.

Local Hazard Mitigation Plan Update
38 3.2 Identifying Hazards
Definition of Hazards
For the purposes of the City of Cathedral City’s Local Hazard Mitigation Plan (LHMP), hazards are defined as natural, technological, or human-caused events that have the potential to cause loss of life, injury, property damage, economic disruption, and environmental degradation. These hazards can be categorized into two primary types:

Chronic hazards are long-term, ongoing conditions that gradually impact the community over time.

These include extreme heat, drought, air quality degradation, and water resource shortages, which accumulate over years or decades and exacerbate vulnerabilities.

Acute hazards are sudden-onset, high-impact events that occur rapidly with little warning. These include earthquakes, flash floods, wildfires, hazardous materials spills, high-wind events, and power outages, which can cause immediate destruction and necessitate emergency response efforts.

Methodology for Hazard Selection
Hazards for the 2025 LHMP were determined by examining hazards previously analyzed in the most recent LHMP revision as well as additional hazards identified by the City through internal solicitation from participants in the internal interview process for the LHMP.

The National Risk Index identifies 18 specific hazards that may affect communities across the United States. Not all of these hazards were included in the LHMP update. Each hazard is addressed below along with justifications as to why they may not have been included.

Hazard Included Explanation
Avalanche No The City of Cathedral City does not experience significant snowfall; therefore, this hazard Is not applicable to the City.

Coastal
Flooding
No The City of Cathedral City does not have any coastline; therefore, this hazard is not applicable to the City.

Cold Wave No Southern California is known for its temperate and warm climate; therefore, this hazard is not applicable to the City.

Drought Yes This hazard is included in the LHMP.

Earthquake Yes This hazard is included in the LHMP.

Local Hazard Mitigation Plan Update
39 Hail No This hazard was not determined to be significant enough to include in the LHMP. Related hazards are included as “High wind/storms”.

Hazard Included Explanation
Heat Wave Yes This hazard is included under “Extreme Heat”.

Hurricane No Hurricanes rarely impact Southern California; therefore, this hazard is not applicable to the City. Similar impacts are examined under “Flooding” and “High wind/storms”.

Ice Storm No Southern California is known for its temperate and warm climate; therefore, this hazard is not applicable to the City.

Landslide Yes This hazard is included.

Lightning No This hazard was not determined to be significant enough to include in the LHMP. Related hazards are included as “High wind/storms”.

Riverine
Flooding
Yes This hazard is included as “Flooding”
Strong Wind Yes This hazard is included as “High wind/storms”.

Tornado No Tornadoes are extremely rare in Southern California; therefore, this hazard is not applicable to the City.

Tsunami No The City of Cathedral City does not border a major body of water and is sufficiently inland to be insulated from immediate tsunami impacts; therefore, this hazard is not applicable to the City.

Volcanic
Activity
No There are no active volcanos in Southern California; therefore, this hazard is not applicable to the City.

Wildfire Yes This hazard is included under “Fire”.

Winter
Weather
No Southern California is known for its temperate and warm climate; therefore, this hazard is not applicable to the City.

To ensure consistency with best practices, regulatory requirements, and evolving hazard conditions, the Planning Team conducted a comprehensive review of hazard planning documents, integrating scientific data and jurisdictional priorities from the following sources:

Federal Hazard Planning Documents
• FEMA Local Hazard Mitigation Plan (LHMP) Guidance (44 CFR §201.6): Defines requirements for hazard identification and risk assessment to maintain eligibility for federal hazard mitigation funding.
• FEMA National Risk Index (2023): Provides a nationwide ranking of hazard exposure, including earthquakes, wildfires, flooding, and extreme heat, which are highly relevant to Cathedral City.

Local Hazard Mitigation Plan Update
40 • NOAA National Centers for Environmental Information (NCEI) Storm Events Database:

Documents historical extreme weather events, including heatwaves, monsoonal storms, and atmospheric river-driven flooding affecting the Coachella Valley. • United States Geological Survey (USGS) Earthquake Hazards Program: Identifies fault systems, seismic activity, and ground shaking potential impacting Cathedral City, particularly the San Andreas Fault and nearby secondary fault systems.

State of California Hazard Planning Documents
• 2023 California State Hazard Mitigation Plan (SHMP): Provides a statewide risk assessment, including wildfire, flooding, earthquakes, drought, and extreme heat, with specific implications for Riverside County and the Coachella Valley.
• California’s Fourth Climate Change Assessment (2018): Uses downscaled climate models to project future hazard conditions, such as increased wildfire risk, more frequent and prolonged heat waves, and changing precipitation patterns contributing to flood and drought risk. • California Department of Forestry and Fire Protection (CAL FIRE) Fire Hazard Severity Zone Map (2022): Identifies areas of elevated fire hazard severity, particularly in wildland-urban interface (WUI) areas surrounding Cathedral City.
• California Adaptation Planning Guide (2020): Establishes a framework for integrating climate adaptation and resilience strategies into local hazard mitigation planning.

Regional and Local Hazard Planning Documents
• Riverside County Multi-Jurisdictional Hazard Mitigation Plan (MJLHMP) (2023): Establishes countywide hazard assessments and highlights multi-jurisdictional risk mitigation priorities that align with Cathedral City.
• Cathedral City General Plan Safety Element (2024 Update): Integrates hazard mitigation, land use planning, and emergency preparedness, ensuring compliance with SB 379 and SB 1035. • First Street Foundation Risk Factor Data (2024): Provides probabilistic modeling for flood, wildfire, and extreme heat risks at the parcel level, supporting localized risk assessment and infrastructure planning.

Methodology
Local Hazard Mitigation Plan Update
41 In January 2025, a hazards and vulnerability assessment workshop was conducted with the City of Cathedral City and with local stakeholders. During the workshop, attendees evaluated the risk of hazards suggested in the course of plan development.

Based in part on elements of the Critical Priority Risk Index, modified for an increased emphasis on future risks using standard climate risk assessment categorization, participants were asked to give their opinion on the assigned scores for each hazard.

This information was used to calculate the Modified Calculated Probability Risk Index score. The CPRI is a common methodology used in hazard mitigation plans to quantify risk. However, it does not give sufficient weight to risks from climate change or other future events.

The Modified CPRI is calculated in the following manner:
((Severity (Present)*0.3)+(Probability (Present)*0.45)+(Severity (Future)*0.3)+(Probability (Future)*0.45))
Hazards Matrix
This LHMP will use the following definitions throughout Section 3 to allow policymakers and planners to use the LHMP to inform City priorities and planning decisions.

Probability Definition
Very Unlikely Less than 5% probability of occurrence
Local Hazard Mitigation Plan Update
42 Unlikely Greater than 5% and less than 30% probability of occurrence Moderate Greater than 30% and less than 60% probability of occurrence Likely Greater than 60% and less than 95% probability of occurrence Very Likely Greater than 95% probability of occurrence

3.3 Hazard Profiles

3.3.1 Extreme Heat
Description
Extreme heat refers to prolonged periods of excessively high temperatures that exceed historical norms for Cathedral City and the surrounding Coachella Valley region. These events are often intensified by low humidity, minimal nighttime cooling, and heat retention in urban areas. The severity of an extreme heat event is influenced not only by absolute temperature values but also by the duration of sustained heat, the presence of warm nighttime temperatures, and the ability of the built and natural environment to dissipate heat effectively. As temperatures remain high for extended periods, the risks to public health, infrastructure, and ecosystems increase, particularly for vulnerable populations such as the elderly, young children, individuals with pre-existing health conditions, and outdoor workers.

Extreme heat presents cascading risks that extend beyond personal discomfort. Heat-related illnesses, including heat exhaustion and heat stroke, become more prevalent as prolonged exposure to high temperatures strains the human body’s ability to regulate heat. Critical infrastructure is also affected, as increased demand for cooling places stress on the power grid, often leading to rolling blackouts and brownouts. Roadways and railways can suffer physical damage due to heat-induced expansion, while urban water systems experience elevated evaporation rates and greater demand for hydration and cooling. Ecosystems are not immune to these effects, as prolonged extreme heat can contribute to drought conditions, reduce soil moisture, and intensify wildfire risks.

The National Weather Service (NWS) defines extreme heat in terms of both daily maximum temperatures and the heat index, which accounts for the combined effects of heat and humidity on human perception of temperature. The heat index, often referred to as the "feels like" temperature, plays a critical role in issuing heat-related warnings and advisories. When the heat index exceeds 105°F for two or more consecutive days, the NWS typically issues an Excessive Heat Warning, signaling that Local Hazard Mitigation Plan Update
43 conditions may pose a significant risk to public health. A Heat Advisory is issued at lower thresholds when conditions are expected to cause moderate health risks, particularly for vulnerable populations.

According to Cal-Adapt and regional climate models, extreme heat events in Cathedral City are expected to intensify due to climate change. The key heat metrics include:
• Extreme Heat Days – A day when the daily maximum temperature exceeds the 98th percentile of historical highs (April–October, based on 1961–1990 records). • Warm Nights – A night when the daily minimum temperature remains above the 98th percentile of historical nighttime lows, reducing the ability of the body to recover from daytime heat stress.
• Extreme Heat Waves – A period of four or more consecutive extreme heat days and warm nights, leading to increased health risks, higher energy demand, and infrastructure strain.

According to climate projections, Cathedral City currently experiences approximately seven days per year with a heat index exceeding 113°F, but this number is expected to increase to 20 days per year by 2050.

Urban areas can experience elevated temperatures due to the Urban Heat Island (UHI) effect, a phenomenon in which built environments absorb and retain heat more than surrounding rural areas.

Surfaces such as asphalt roads, concrete sidewalks, and dark rooftops absorb solar radiation during the day and release heat more slowly at night, leading to higher ambient temperatures. Additionally, limited vegetation and tree canopy coverage reduce opportunities for natural cooling through evapotranspiration. Waste heat from industrial activity, vehicular emissions, and air conditioning systems further amplifies local temperatures.

In Cathedral City, certain areas exhibit elevated heat exposure due to urban density, high pavement coverage, and limited green space. Studies indicate that daytime maximum temperatures within heat islands can vary by as much as 7°F from surrounding rural areas, and more importantly, these areas retain heat overnight, preventing cooling.

Location and Extent
Extreme heat is a citywide hazard in Cathedral City, affecting all neighborhoods due to the region’s desert climate, the urban heat island (UHI) effect, and projected increases in the frequency and intensity of heat waves due to climate change. The Coachella Valley experiences approximately 348 sunny days per year, with summer high temperatures regularly exceeding 110°F. These extreme Local Hazard Mitigation Plan Update
44 conditions create significant health and infrastructure risks, particularly for vulnerable populations, older buildings with poor insulation, and neighborhoods with limited tree canopy coverage.

Industrial areas, major transportation corridors, and residential neighborhoods with limited green space are particularly vulnerable to prolonged heat retention and elevated daytime and nighttime temperatures.

Industrial zones and commercial corridors within Cathedral City contribute to significant heat accumulation due to extensive pavement, asphalt, and metal structures that absorb and retain heat well into the evening. These areas lack sufficient tree canopy coverage and vegetation to provide natural cooling, leading to sustained high temperatures that intensify the urban heat island effect. Additionally, heat generated from industrial activity and vehicular emissions further exacerbates localized temperature increases.

High-traffic corridors such as East Palm Canyon Drive (Highway 111), Date Palm Drive, and Ramon Road contribute to increased localized temperatures. The dark asphalt surfaces of major roadways absorb heat throughout the day, releasing it slowly at night, limiting cooling and amplifying the heat island effect. The combination of traffic congestion and waste heat from vehicles intensifies this effect, particularly in adjacent residential areas.

Residential areas with low tree canopy coverage, particularly in older neighborhoods and high-density developments, experience prolonged heat stress. Many homes in Cathedral City were built before modern energy efficiency standards and lack proper insulation and cooling systems. As a result, indoor temperatures in these buildings can become dangerously high, posing severe risks to occupants, especially low-income residents who may be unable to afford air conditioning Relationship to Land Use and Development
Land use and urban development patterns play a critical role in Cathedral City’s extreme heat vulnerability. The city’s mix of residential, commercial, and industrial land uses, combined with widespread impervious surfaces, intensifies local temperature increases.

The predominance of hardscaped surfaces in Cathedral City-such as roads, parking lots, and industrial sites-significantly reduces the potential for natural cooling. In commercial districts and industrial zones, high heat retention is exacerbated by the lack of shade and vegetation. The city’s tourism and hospitality industry, which includes large hotels, resorts, and shopping centers, also contributes to heat retention due to the extensive use of reflective glass and concrete surfaces.

Local Hazard Mitigation Plan Update
45 Transportation infrastructure further amplifies heat retention across the city. Cathedral City is bisected by major roadways, including Highway 111 and Interstate 10, which contribute to heat buildup.

Freeway-adjacent neighborhoods experience compounded heat exposure due to the combination of direct solar radiation on asphalt and emissions from high traffic volumes.

Older residential developments, particularly those built before California’s modern building energy codes, have limited insulation, outdated cooling systems, and roofing materials that absorb rather than reflect heat. These buildings are more susceptible to overheating, increasing energy costs for residents and heightening health risks for those who lack access to adequate cooling. Green spaces such as Panorama Park, Century Park, Ocotillo Park and the soon to be completed Esperanza Park provide some relief from extreme heat, but Cathedral City’s overall tree canopy coverage is low, further intensifying urban heat stress.

Magnitude and Severity
Unlike some other natural hazards, extreme heat lacks a singular, universally accepted intensity scale, such as the Modified Mercalli Intensity Scale for earthquakes or the Saffir-Simpson Hurricane Wind Scale for hurricanes. Instead, the severity of extreme heat events is assessed using a combination of temperature thresholds, heat indices, and frequency and duration metrics, which collectively provide a comprehensive measure of the hazard’s magnitude and potential impacts.

National Weather Service (NWS) Heat Index
Local Hazard Mitigation Plan Update
46 The NWS Heat Index is the primary tool used to quantify how hot it "feels" by factoring in both actual air temperature and relative humidity. This index plays a critical role in issuing heat-related alerts and warnings. The NWS issues an Excessive Heat Warning when the heat index surpasses 105°F for at least two consecutive days. A Heat Advisory may be issued when heat index values pose a moderate risk to public health, particularly for vulnerable populations such as the elderly, outdoor workers, and individuals with pre-existing health conditions.

Cal-Adapt Extreme Heat Metrics
California’s Cal-Adapt system, developed by Cal OES and UC Berkeley’s Geospatial Innovation Facility, provides historical and projected climate data to help communities assess and plan for extreme heat risks. Cal-Adapt defines extreme heat through three primary measurements:
• Extreme Heat Days – A Day when the maximum temperature exceeds the 98th percentile of historical daily highs (based on 1961–1990 data).
• Warm Nights – A night when the minimum temperature remains above the 98th percentile of historical lows for the same period, limiting nighttime cooling and increasing heat stress. • Extreme Heat Waves – A period of four or more consecutive Extreme Heat Days and Warm Nights, significantly increasing health risks, energy demand, and infrastructure stress.

Severity of Extreme Heat
Extreme heat events in Cathedral City are becoming more frequent, prolonged, and intense due to climate change and the urban heat island (UHI) effect. The city, located in the Coachella Valley, experiences extremely high summer temperatures, often exceeding 120°F between June and September . The number of days with temperatures exceeding 113°F is projected to increase from 7 days per year today to 20 days per year by 2050. The UHI effect is exacerbated by the city’s constructed environment, where asphalt, concrete, and other heat-absorbing materials contribute to sustained heat retention, particularly in areas with limited vegetation and tree canopy coverage Health and Infrastructure Impacts
The intensification of extreme heat presents severe risks to human health, critical infrastructure, and economic stability. Prolonged exposure to high temperatures significantly increases the likelihood of heat-related illnesses, including heat exhaustion and heat stroke. Vulnerable populations, such as Local Hazard Mitigation Plan Update
47 elderly residents, low-income households, outdoor workers, and individuals with pre-existing health conditions, are at heightened risk. The healthcare system in Cathedral City is expected to face increased demand for emergency medical services due to rising heat-related conditions.

Extreme heat also places a substantial strain on energy infrastructure. Increased air conditioning use leads to higher electricity demand, raising the likelihood of power outages, rolling blackouts, and grid failures, especially during prolonged heat waves. Cathedral City already experiences significant energy demand for cooling, with 315 cooling days per year today, projected to increase to 326 days per year by 2050.

Additionally, high temperatures accelerate infrastructure deterioration, affecting roads, bridges, and rail systems. Asphalt softening, pavement buckling, and rail track warping are expected to increase, disrupting transportation networks and local economic activities.

Historical Occurrences of Extreme Heat
FEMA Disaster Declarations
Incident
Subcategory County FEMA Declaration String
Calendar Year of
Declaration
Date
Month
Declaration
Date
Declaration
Title State
None None None None None None None None
California Governor-declared Declarations

DATE OF DISASTER TYPE OF DISASTER COUNTIES INVOLVED
None None None
List of Governor-declared disasters for property tax purposes since 1991. Source: California State Board of Equalization Cathedral City and the greater Coachella Valley region have experienced multiple extreme heat events over the past several decades, resulting in increased public health risks, surges in energy demand, and cascading infrastructure failures. The frequency, duration, and intensity of these heat waves have intensified due to climate change, placing additional stress on vulnerable populations, emergency response systems, and critical infrastructure.
• July 2006 Heat Wave: In July 2006, California experienced one of its most intense and prolonged heat waves, lasting nearly three weeks. Temperatures soared well above 115°F in the Coachella Valley, with Palm Springs recording highs of 121°F. The extreme heat caused Local Hazard Mitigation Plan Update
48 widespread health emergencies, including heat stroke, dehydration, and respiratory distress, particularly among seniors, outdoor workers, and individuals without access to air conditioning. Emergency room visits surged, and the strain on the electrical grid led to rolling blackouts in multiple locations throughout Southern California. • July 2018 Heat Wave: During early July 2018, an intense heat wave struck Southern California, with Palm Springs reaching 120°F and Thermal hitting 121°F. This event resulted in a spike in heat-related illnesses and power disruptions across Riverside County. The combination of prolonged high temperatures and dry conditions exacerbated wildfire risks, leading to several brush fires in the region.
• August 2020 Heat Wave and Rolling Blackouts: In August 2020, California experienced an extreme heat wave, triggering the state's first rolling blackouts in nearly two decades. Cathedral City, along with the rest of the Coachella Valley, saw temperatures soar beyond 120°F. This event placed unprecedented stress on California’s power grid, with the California Independent System Operator (CAISO) declaring a Stage 3 Emergency due to electricity demand exceeding available supply. Nearly 500,000 residents across the state lost electricity, affecting cooling systems, refrigeration, and critical medical equipment, further endangering vulnerable populations.
• September 2020 Labor Day Weekend Heat Wave: In early September 2020, another recordbreaking heat wave struck California. Palm Springs recorded a high of 121°F, matching its alltime record. The extreme temperatures led to increased 911 emergency calls, emergency room visits, and widespread power disruptions. This event also exacerbated air pollution and groundlevel ozone formation, leading to higher rates of respiratory illnesses.

Probability and Effects of Future Conditions
Local Hazard Mitigation Plan Update
49 Overall probability over next five years: Likely.

Extreme heat in Cathedral City is projected to intensify in frequency, severity, and duration due to the ongoing effects of climate change. Rising global temperatures, combined with the urban heat island (UHI) effect, will lead to more frequent, longer-lasting, and higher-intensity heat waves, posing serious risks to public health, infrastructure, and economic stability.

With Cathedral City’s location in the Coachella Valley, extreme heat events are already common, but they are expected to worsen in the coming decades. Heat waves will be more frequent and prolonged, increasing the likelihood of health emergencies, power disruptions, and infrastructure degradation.

Projected Temperature Increases
Under current climate change scenarios, Cathedral City is expected to experience an increase in extreme heat days, with temperatures exceeding 113°F rising from 7 days per year today to 20 days per year by 2050.

The increase in extreme temperatures will intensify the risks associated with heat-related illnesses, economic productivity losses, and increased energy consumption for cooling. With an expected rise in cooling degree days, Cathedral City’s electricity usage for cooling purposes is projected to increase by

5.8% by 2050.

Increased Frequency of Heat Waves
Historically, heat waves in Cathedral City have been intense but relatively infrequent. Climate projections indicate that heat waves lasting three or more consecutive days will become significantly more common. The likelihood of experiencing at least one extreme heat wave per year will increase dramatically, leading to disruptions in daily life, elevated cooling costs, and a heightened burden on vulnerable populations, including low-income households, outdoor workers, and elderly residents.

Longer Duration and Warmer Nights
Not only will extreme heat waves become more frequent, but their duration will also increase, making multi-day heat waves the norm rather than the exception. The combination of rising daytime Local Hazard Mitigation Plan Update
50 temperatures and warmer nighttime temperatures will limit opportunities for heat recovery, increasing the risk of heat stress and heat-related illnesses.

Historically, Cathedral City has experienced hot summer nights where temperatures remain high, but by 2050, this number is expected to increase significantly, placing additional strain on the power grid and increasing the likelihood of rolling blackouts.

Warmer nights pose a significant health risk for vulnerable populations, as the lack of cooling can prevent the human body from recovering from daytime heat stress, increasing the risk of heat exhaustion, heat stroke, and cardiovascular complications. The increased demand for air conditioning during nighttime hours will also heighten energy demand, increasing the risk of power grid failures during peak heat waves.

3.3.2 Drought
Hazard Description
Drought is a prolonged period of below-average precipitation resulting in water shortages that impact people, agriculture, ecosystems, and industries. Unlike other natural hazards, droughts develop gradually and can persist for months or even years. Drought severity is often exacerbated by high temperatures, low humidity, and increased evaporation rates, further straining natural and human systems.

According to the National Weather Service (NWS), drought is defined as a deficiency of moisture severe enough to adversely affect people, animals, or vegetation over a sizable area. The U.S. Drought Monitor classifies drought conditions on a scale from "Abnormally Dry (D0)" to "Exceptional Drought (D4)," based on multiple indicators such as precipitation deficits, soil moisture levels, and reservoir storage.

Droughts are categorized into five primary types based on their causes and impacts:

Local Hazard Mitigation Plan Update
51 • Meteorological Drought: Occurs when precipitation levels fall significantly below the historical average for an extended period. In California, shifts in climate patterns such as La Niña and El Niño influence drought conditions. The El Niño-Southern Oscillation (ENSO) cycle plays a crucial role in regional precipitation variability, with La Niña phases typically linked to drier conditions.
• Agricultural Drought: Results from insufficient soil moisture to sustain healthy crop and pasture growth. This is particularly concerning for California’s Central Valley, where agriculture relies heavily on surface water and groundwater supplies. Prolonged droughts lead to lower crop yields, increased irrigation demands, and higher food prices. • Hydrological Drought: Occurs when surface and groundwater supplies decline due to extended precipitation deficits, leading to reduced river flows, depleted reservoirs, and dropping groundwater tables. In Southern California, where water supplies depend on the Sierra Nevada snowpack, rising temperatures and altered precipitation patterns due to climate change have reduced snowpack accumulation, leading to earlier snowmelt and lower summer water availability.
• Socioeconomic Drought: Happens when water shortages disrupt economic activities, public infrastructure, and daily life. Drought conditions often result in stricter water use regulations, increased utility costs, and economic losses in sectors such as agriculture, energy production, and tourism. Additionally, extended droughts elevate wildfire risk, increasing emergency response costs and insurance premiums.
• Ecological Drought: Disrupts natural ecosystems by affecting wildlife, aquatic habitats, and vegetation. Decreased streamflows and lower reservoir levels result in higher water

temperatures, declining fish populations, and habitat loss for native species. Prolonged droughts have also contributed to tree mortality and increased vulnerability to pests, such as bark beetle infestations.

Magnitude and Severity
Unlike sudden-onset hazards such as earthquakes or hurricanes, drought is a slow-developing phenomenon lacking a universally accepted severity scale. Instead, its magnitude and severity are evaluated using multiple indices that consider precipitation deficits, soil moisture levels, streamflow reductions, and socio-economic impacts.

Palmer Drought Severity Index (PDSI): The PDSI is a widely utilized metric that assesses long-term drought conditions by analyzing precipitation, temperature, and soil moisture data. It classifies drought severity on a scale from +4.0 (extremely wet) to -4.0 (extreme drought). This index is particularly Local Hazard Mitigation Plan Update
52 pertinent to Southern California, where prolonged precipitation deficits and rising temperatures contribute to persistent drought conditions.

US Drought Monitor Classification Scheme.

Source: https://droughtmonitor.unl.edu/About/AbouttheData/DroughtClassification U.S. Drought Monitor Classification: The U.S. Drought Monitor categorizes drought severity into five levels, serving as a critical tool for emergency declarations, water conservation measures, and agricultural impact assessments:
• D0 (Abnormally Dry): Short-term dryness, slower crop growth, and increased fire risk. • D1 (Moderate Drought): Some damage to crops, voluntary water restrictions implemented. • D2 (Severe Drought): Likely crop losses, water shortages, and mandatory restrictions. • D3 (Extreme Drought): Major crop losses, widespread water shortages, and heightened fire risk. • D4 (Exceptional Drought): Widespread water emergencies, ecosystem degradation, and significant economic losses.

Standardized Precipitation Index (SPI): The SPI measures drought intensity over various time scales, ranging from one month to multiple years. It quantifies deviations in precipitation from historical averages and is particularly useful for assessing short-term drought impacts on urban water supplies.

Agencies such as the California Department of Water Resources (DWR) and the National Oceanic and Atmospheric Administration (NOAA) utilize SPI data to project seasonal drought risks for Southern California.

California Snow Water Equivalent (SWE) Index: A significant portion of Southern California’s water supply depends on the Sierra Nevada snowpack. The SWE Index measures the amount of water stored in the snowpack; lower SWE values indicate reduced runoff and heightened drought risk. Climate projections suggest that by 2050, SWE levels could decline by up to 65%, further exacerbating water shortages.

Local Hazard Mitigation Plan Update
53 Water Supply Vulnerabilities
Drought-prone areas within Cathedral City are not defined by physical geography but rather by their reliance on vulnerable water sources. The city’s primary water supply challenges stem from three key sources:

Groundwater Basins: Cathedral City depends on the Coachella Valley Groundwater Basin, a critical groundwater resource that provides water for municipal and industrial use.. The Indio Subbasin, which underlies Cathedral City and the majority of the Coachella Valley, contains 29.8 million acre-feet of groundwater in storage in the first 1,000 feet below the ground surface. The Indio Subbasin is replenished with imported Colorado River water which has averaged 124,592 acre-feet of recharged water since 2007. Historical low groundwater levels in the Indio Subbasin occurred in the years around 2009 but have since risen, recently achieving groundwater sustainability due to source substitution projects, conservation programs, and recharge operations.

Imported Water Supplies: Cathedral City relies on groundwater from the Indio Subbasin which is replenished by imported water from the Colorado River via the Colorado River Aqueduct. The Colorado River Basin has been in persistent drought since 2000, causing inconsistent snowpack and long-term water security concerns. State Water Project (SWP) water deliveries have averaged 45% of allocated supply since 2009 with allocations between 5% and 15% during extreme drought years, further stressing local water availability.

Surface Water Bodies: While Cathedral City lacks major natural lakes or reservoirs, it relies on regional storage facilities and groundwater replenishment programs managed by CVWD. These facilities experience heightened evaporation rates during prolonged drought periods, influencing their effectiveness in maintaining stable water supplies.

Urban Development and Land Use Impacts on Drought Resilience Urban development and land use patterns in Cathedral City influence the city’s vulnerability and resilience to drought. Several key sectors are particularly impacted:

Residential Areas: Many residential neighborhoods in Cathedral City rely heavily on outdoor irrigation for landscaping, making them primary targets for mandatory water restrictions during drought emergencies. Landscaping water use accounts for a significant portion of household consumption, and drought conditions may lead to significant reductions in permitted irrigation.

Local Hazard Mitigation Plan Update
54 Commercial and Industrial Sectors: Cathedral City has a growing commercial and industrial sector, which depends on stable water supplies for cooling, processing, and other industrial applications. Water restrictions may lead to increased operational costs, production delays, and economic losses, particularly for businesses that rely on high water usage.

Parks and Green Spaces: Public parks, golf courses, and urban green spaces face increased vulnerability to drought-induced water shortages. Vegetation stress and loss of tree cover may lead to higher temperatures and increased urban heat island effects, exacerbating extreme heat conditions.

Historical Occurrences of Drought
FEMA Disaster Declarations
Incident
Subcategory County FEMA Declaration String
Calendar Year of
Declaration
Date
Month
Declaration
Date
Declaration
Title State
None None None None None None None None
California Governor-declared Declarations

DATE OF DISASTER TYPE OF DISASTER COUNTIES INVOLVED
October 2021 Drought All 58 counties (including Riverside County) List of Governor-declared disasters for property tax purposes since 1991. Source: California State Board of Equalization Drought is a recurrent hazard in California, with Cathedral City and the greater Coachella Valley experiencing multiple severe droughts in recent decades. These prolonged dry periods have strained water supplies, increased wildfire risk, and led to mandatory conservation measures. Historical drought occurrences highlight the increasing frequency and intensity of dry conditions, exacerbated by climate change and growing water demand.

Between 2000 and 2023, Cathedral City’s Whitewater River watershed experienced drought conditions for 80% of all weeks. Of these, 17% were classified as Extreme or Exceptional Drought (D3-D4), signifying severe impacts on water supply, agriculture, and wildfire conditions. • 2011–2017 California Drought: The 2011–2017 drought was one of the most severe and prolonged in California’s history. By 2014, nearly the entire state was classified under Severe Drought (D2) or worse, leading to significant reductions in groundwater levels and emergency water conservation mandates. In response, Governor Jerry Brown declared a statewide Local Hazard Mitigation Plan Update
55 emergency, requiring jurisdictions-including Cathedral City-to reduce water usage by at least 25%. Water restrictions remained in effect until early 2017, when consecutive winter storms replenished some of California’s reservoirs and aquifers • 2020–2022 Drought: Beginning in late 2020, another significant drought developed across California. By 2022, 97% of Riverside County, including Cathedral City, was classified under Extreme Drought (D3) or higher. Key impacts included:
• Reduced snowpack levels in the Sierra Nevada, a major source of water for California, leading to decreased runoff into reservoirs.
• Historic low water levels in the Colorado River Basin. • Increased wildfire risk, as prolonged drought dried vegetation earlier in the season, fueling more intense fires.

FEMA Disaster Declarations
While droughts do not typically result in FEMA Major Disaster Declarations (DR) in the same way as earthquakes or wildfires, their cascading impacts-such as wildfires, water shortages, and economic disruptions-have contributed to multiple FEMA disaster declarations in California. • FEMA DR-4323 (2017) provided federal assistance for wildfire damages exacerbated by prolonged drought conditions.
• FEMA DR-4558 (2020) was declared in response to wildfires intensified by ongoing drought, highlighting the link between prolonged dry periods and increased fire risk.

Federal and state drought emergency declarations have been issued multiple times, including Governor-declared drought emergencies in 2014, 2015, 2021, and 2022, all of which impacted Cathedral City.

Probability and Effects of Future Conditions
Overall probability over next five years: Likely.

Drought conditions in Cathedral City are anticipated to increase in frequency, duration, and severity due to climate change, rising temperatures, and shifting precipitation patterns. Climate models and historical data indicate that the Coachella Valley will experience longer and more intense dry periods, punctuated by short, intense rainfall events. These changes are expected to lead to reduced water availability and inefficient groundwater recharge, compounding stress on the region’s already limited water resources.

Local Hazard Mitigation Plan Update
56 More Frequent and Prolonged Droughts: Projections suggest that Cathedral City and the surrounding Coachella Valley will experience increasing drought conditions nearly every decade, a significant shift from historical patterns where major droughts occurred approximately every 20 to 30 years.

Rising temperatures will exacerbate drought severity. By 2050, Cathedral City is projected to experience an increase in extreme heat days, with temperatures above 113°F rising from 7 days per year today to 32 days per year. These higher temperatures will accelerate evaporation rates, deplete soil moisture, and increase water loss from reservoirs, intensifying drought severity.

Declining Water Supplies and Increased Dependence on Imported Water: Cathedral City relies on groundwater from the Indio Subbasin, which is replenished with imported Colorado River water, and State Water Project (through an exchange agreement with Metropolitan Water District of Southern California),. Groundwater levels in the Indio Subbasin, which serves Cathedral City, reached historical low levels in 2009 but have since rebounded, recently achieving groundwater storage sustainability..

Groundwater production in the Indio Subbasin during water year 2024 was 267,495 acre-feet and has averaged 272,308 acre-feet since 2017. Source substitution projects and conservation programs have continued to support efforts to minimize supply needed from the Indio Subbasin.

The Colorado River Basin, a primary supply to replenish the Indio Subbasin, has been in persistent drought since 2000, with key reservoirs like Lake Mead and Lake Powell reaching historic lows. Federal negotiations on mandatory water cuts for the seven Colorado River basin states could reduce allocations to the Coachella Valley Water District (CVWD) who is an importer of Colorado River water.

Extreme Weather and Precipitation Variability ("Precipitation Whiplash"): Climate models indicate that Cathedral City and Southern California will experience more extreme shifts between drought and flooding, known as "precipitation whiplash." Prolonged dry conditions will be abruptly followed by intense rainfall, leading to rapid runoff, erosion, and reduced groundwater replenishment. Despite occasional heavy precipitation events, the overall annual rainfall in Cathedral City is expected to remain at approximately 4.5 inches per year, meaning water shortages will persist. The frequency of extreme atmospheric river storms, which deliver the bulk of California’s precipitation, is expected to increase by 25% by 2070. However, these events will not be evenly distributed throughout the year, limiting their effectiveness in replenishing groundwater or restoring reservoir levels.

3.3.3 Fire
Description
Local Hazard Mitigation Plan Update
57 Urban fires occur in developed areas and are fueled by buildings, industrial operations, vehicles, and hazardous materials. Cathedral City faces elevated risks due to its mix of commercial, residential, and industrial areas, as well as major transportation corridors. While the city does not have a high concentration of large industrial facilities, it still has fuel storage sites, older structures, and commercial centers that increase fire risks.

Several key factors contribute to urban fire risk in Cathedral City. Commercial and industrial fires can originate from electrical failures, mechanical malfunctions, or hazardous materials accidents. Older commercial buildings and retail centers may lack modern fire-resistant materials, increasing the risk of rapid fire spread. The city also faces risks from electrical and transportation-related fires, as major roadways such as Interstate 10 and Highway 111 experience heavy truck traffic carrying hazardous cargo. Additionally, the city is traversed by multiple power transmission lines, increasing the risk of fire ignition during extreme heat or high wind conditions.

Wildfire and Wildfire Smoke: Although Cathedral City is not located in a Very High Fire Hazard Severity Zone (FHSZ), it is still vulnerable to wildfire risks from surrounding foothills and the nearby Santa Rosa and San Jacinto Mountains National Monument. Embers carried by Santa Ana winds can ignite dry vegetation in vacant lots, open spaces, and urban landscaping, increasing the risk of localized fire outbreaks. Wildfires in adjacent mountainous areas have the potential to cut off access to utilities, impact evacuation routes, and degrade air quality.

Air Quality Impacts: Wildfires across California, particularly in Riverside County and the nearby San Bernardino National Forest, generate smoke plumes that carry fine particulate matter (PM2.5), carbon monoxide, and other pollutants. Cathedral City experiences periodic "Unhealthy" air quality conditions (AQI 150-200) due to wildfire smoke, disproportionately affecting vulnerable populations such as children, the elderly, and individuals with respiratory conditions.

Urban Vegetation and Fuel Sources: While Cathedral City does not have dense forests, dry grasses, palm trees, and landscaping vegetation create fire risks, particularly during extreme drought conditions.

Areas with vacant lots, parks, and right-of-way vegetation can act as fuel sources if not properly managed. Prolonged heat waves and extended droughts increase vegetation dryness, making urban fire hazards more severe.

Cathedral City’s moderate wildfire risk over the next 30 years is influenced by both natural and humanmade factors. According to First Street Foundation’s Risk Factor data, approximately 6,092 properties, or 30% of all parcels, in Cathedral City have some level of wildfire exposure, primarily from embers or adjacent vegetation in the wildland-urban interface (WUI).

Local Hazard Mitigation Plan Update
58 Location and Geographic Extent
Cathedral City faces fire hazards shaped by land use patterns, commercial activities, transportation infrastructure, and regional wildfire exposure. While the city does not include extensive designated Very High Fire Hazard Severity Zones (VHFHSZs) under CAL FIRE’s 2025 Fire Hazard Severity Zone Maps, it remains vulnerable to urban fire risks, transportation-related fire hazards, and indirect wildfire impacts, including wind-driven ember transport, degraded air quality, and post-fire debris or mudflow events originating from neighboring jurisdictions.

Fire hazard areas in Cathedral City can be categorized into four general risk categories Commercial and Industrial Fire: Cathedral City’s mix of commercial, industrial, and mixed-use development areas increases exposure to structural and operational fire risks. Key hazards include:
• Aging electrical systems in older strip malls and shopping centers, • Fuel storage and mechanical operations in automotive, warehouse, and light manufacturing businesses,
• Proximity of commercial zones to residential neighborhoods, which can accelerate fire spread if initial containment fails.

Residential Fire: While Cathedral City is not formally classified in CAL FIRE’s 2025 VHFHSZ for LRAs, structural fire risks remain-especially in:
• Older neighborhoods with wood-frame homes, limited fire suppression systems, or poor defensible space,
• Multi-family and mobile home parks, where structure spacing and egress limitations increase vulnerability,
• Residences near dry washes or desert vegetation prone to wind-driven ignition from embers.

Wildfire Risk and Ember Transport: Although Cathedral City lacks a history of large-scale wildfire within its municipal limits, it is indirectly at risk due to its proximity to wildfire-prone areas such as the Santa Rosa and San Jacinto Mountains National Monument. During Santa Ana wind events, embers can travel several miles and ignite:
• Rooftop materials,
• Yard vegetation,
• Dry landscaping in parks and medians.

Local Hazard Mitigation Plan Update
59 Cathedral City also faces secondary risks from mud and debris flows following regional wildfires or heavy storms, particularly when transported via flood control channels from upstream burn scars-an increasingly relevant hazard under future climate conditions.

Transportation and Utility Fire Risk Corridors: High-use transportation corridors and utility alignments present persistent fire hazards:
• Interstate 10 and Highway 111 carry substantial commercial freight and hazardous materials, increasing risk of vehicular or cargo fires,
• Union Pacific rail lines, which traverse the Coachella Valley just north of Cathedral City, carry combustible materials that, if derailed, could pose ignition threats, • Southern California Edison (SCE) transmission infrastructure-particularly overhead highvoltage lines near Flat Top Mountain and Edom Hill-may spark fires during wind or heat stress, especially in dry vegetation zones.

Local Hazard Mitigation Plan Update
60 Relationship to Land Use and Development in Cathedral City The distribution of fire hazards in Cathedral City is closely linked to land use patterns, commercial and residential density, and transportation infrastructure. While Cathedral City does not have a high concentration of heavy industrial activity, the city’s mix of commercial centers, industrial storage, transportation corridors, and high-density residential areas creates distinct fire risk zones.

Cathedral City’s zoning and land use plan designates significant portions of the city for commercial and mixed-use development, which increases vulnerability to structural fires, electrical equipment failures, and fuel-related ignition sources. The presence of auto repair shops, warehouses, gas stations, and commercial centers contributes to fire risk, especially in older buildings that may lack modern fireresistant materials and suppression systems.

Higher-density developments, including multi-family residential areas, mobile home parks, and mixeduse districts, increase structure-to-structure fire spread risk. Many residential and commercial buildings in Cathedral City were built before modern fire codes and may not have adequate fire suppression systems, making them more vulnerable to fire hazards.

Additionally, aging electrical infrastructure and the presence of overhead power lines present fire ignition risks. High winds, extreme heat, and electrical faults have historically contributed to fire outbreaks in Southern California communities and remain an ongoing concern for Cathedral City Magnitude and Severity of Fire Hazards
Fire Intensity and Structural Impact – Fire Intensity Scale (FIS): The Fire Intensity Scale (FIS) classifies fire severity based on energy release, flame length, and suppression difficulty. Cathedral City’s fire hazards are most commonly associated with structural fires and transportation-related incidents, with the potential for larger, more intense fire events under extreme conditions. • Class 1 (0-250 kW/m): Small, localized fires in structures or open areas that can be extinguished with standard firefighting methods. This category includes residential fires and minor vehicle fires.
• Class 2 (251-1,000 kW/m): Moderate-intensity fires, including commercial building fires and industrial storage yard fires, requiring coordinated suppression efforts. • Class 3 (1,001-10,000 kW/m): Large warehouse or commercial center fires and wind-driven urban fires that require multi-agency response and pose risks to nearby structures.

Local Hazard Mitigation Plan Update
61 • Class 4 (10,001-50,000 kW/m): Fires involving hazardous materials and fuel storage sites, generating toxic smoke and extreme heat, requiring specialized response. • Class 5 (50,001+ kW/m): Large-scale conflagrations, including multi-structure urban fires, industrial explosions, or catastrophic transportation-related fires, necessitating mass evacuations.

Wildfire Spread and Impact – National Fire Danger Rating System (NFDRS): Although Cathedral City is not located in a Very High Fire Hazard Severity Zone (VHFHSZ), wildfire risks are still present due to ember transport, prolonged drought conditions, and regional fire activity. The National Fire Danger Rating System (NFDRS) categorizes wildfire risk based on weather conditions, fuel moisture, and fire spread potential.
• Low: Fires spread slowly and are easily controlled, with minimal risk of regional impact. • Moderate: Fires ignite in dry grass and urban vegetation, but spread is limited unless driven by high winds.
• High: Fires spread rapidly in dry conditions and can be intensified by ember transport.

Wildfires from surrounding areas can contribute to structural ignitions in Cathedral City. • Very High: Fast-moving fires, especially during Santa Ana wind events, can ignite structures, vehicles, and industrial storage areas, requiring rapid emergency response. • Extreme: Fires exhibit explosive growth, necessitating multi-agency firefighting efforts and evacuations. Embers can travel long distances and create widespread fire hazards.

Ember Transport Risk – Spot Fire Probability Model: Cathedral City’s vulnerability to ember transport is heightened due to proximity to fire-prone areas, high winds, and flammable materials stored in commercial and industrial zones. The Spot Fire Probability Model assesses ember ignition risks based on wind speeds and fuel sources:
• 40-60 mph winds: Embers can travel 1-3 miles, igniting vegetation, rooftops, and storage areas containing flammable materials.
• 80+ mph winds: Embers can travel over 5 miles, significantly increasing the risk of spot fires within urban and commercial areas.

Air Quality Impact – Wildfire Smoke and the Air Quality Index (AQI): Wildfire smoke from regional fires has historically impacted Cathedral City, leading to elevated PM2.5 (fine particulate matter) pollution levels. The Air Quality Index (AQI) system measures wildfire-related pollution and associated health risks:
• AQI 100-150: Unhealthy for sensitive groups, requiring air quality advisories.

Local Hazard Mitigation Plan Update
62 • AQI 151-200: Unhealthy for the general population, prompting recommendations to limit outdoor activities.
• AQI 201-300: Very unhealthy, requiring emergency health advisories and restrictions on outdoor exposure.
• AQI 300+: Hazardous, triggering public health warnings, school closures, and emergency response actions.

Fire Hazard Severity
Urban fire severity in Cathedral City is considered moderate to high, driven by a combination of aging structures, vulnerabilities in electrical infrastructure, and concentrated commercial fire loads.

Although the city does not contain large-scale industrial refineries, specific land uses-such as automotive repair facilities, localized fuel storage sites, and older commercial centers-present structural and operational fire hazards. High-density residential areas, particularly those with wood-frame construction and outdated or absent fire suppression systems, increase the likelihood of structure-tostructure fire spread during ignition events. In many neighborhoods, close proximity between residential and commercial zones contributes to compounded fire risk.

Transportation infrastructure also plays a role in urban fire severity. Interstate 10 and Highway 111, both of which traverse the city, carry high volumes of freight, including hazardous or flammable materials. This increases the potential for vehicular fires, hazardous material releases, or roadside ignitions. These corridors, combined with above-ground electrical infrastructure, create additional ignition pathways, particularly during periods of high temperature and wind.

Wildfire and ember transport risk in Cathedral City is considered moderate. While the city itself is not classified within a Very High Fire Hazard Severity Zone (VHFHSZ) according to CAL FIRE’s 2025 maps, it remains vulnerable to indirect wildfire impacts due to proximity to high-risk wildland areas, including the Santa Rosa and San Jacinto Mountains. Wind-driven wildfire events in these regionsespecially during Santa Ana conditions-can transport embers into the city. These embers can ignite vulnerable rooftops, dry vegetation, and combustible materials in industrial or commercial yards.

Approximately 6,092 properties in Cathedral City, or roughly 30 percent of all parcels, are considered to have some level of wildfire exposure over the next 30 years. This estimate is based on First Street Foundation’s 2024 parcel-level wildfire modeling, which incorporates local building characteristics, surrounding land cover, prevailing wind patterns, and ember susceptibility. Properties with higher exposure are typically located in areas with limited defensible space, older construction, or proximity to ornamental vegetation and dry landscaping.

Local Hazard Mitigation Plan Update
63 The probability of spot fires igniting within the urban core increases significantly during prolonged droughts, particularly when vegetation and surface debris become highly flammable. During extreme fire weather events, such as those driven by Santa Ana winds, the combination of low humidity, high temperatures, and combustible conditions elevates the risk of ember ignitions in older neighborhoods, commercial zones with high fuel loads, and industrial sites. While Cathedral City may not face largescale wildfire spread internally, the cumulative risks posed by urban fire dynamics, regional ember exposure, and climate-driven fuel volatility represent a significant hazard to life safety, property, and air quality.

Historical Occurrences of Fire

FEMA Disaster Declarations
Incident
Subcategory County
FEMA
Declaration
String
Calendar Year of
Declaration
Date
Month
Declaration
Date Declaration Title State
Fire Riverside
County DR-1005-CA 1993 October 10/28/1993 FIRES, MUD/LANDSLIDES, FLOODING, SOIL EROSION CA Fire Riverside
County DR-1498-CA 2004 October 10/24/2004 WILDFIRES CA
Fire Riverside
County DR-1731-CA 2007 November 11/3/2007 WILDFIRES CA
Fire Riverside
County DR-1810-CA 2008 July 7/9/2008 WILDFIRES CA
Fire Riverside
County DR-1884-CA 2010 August 8/31/2010 WILDFIRES CA
Fire Riverside
County DR-4158-CA 2013 July 7/26/2013 WILDFIRES CA
Fire Riverside
County DR-4305-CA 2017 October 10/10/2017 CALIFORNIA WILDFIRES CA Fire Riverside
County DR-4407-CA 2018 August 8/4/2018 CALIFORNIA WILDFIRES CA Fire Riverside
County DR-4558-CA 2020 August 8/22/2020 CALIFORNIA WILDFIRES CA Fire Riverside
County DR-4610-CA 2021 September 9/12/2021 CALIFORNIA WILDFIRES CA Fire or wildfire-related declared disasters in the vicinity of the Coachella Valley, 1953-2024. Source: FEMA California Governor-declared Declarations

DATE OF DISASTER TYPE OF DISASTER COUNTIES INVOLVED
September 9, 2024 Fire (Airport) Orange, Riverside
Local Hazard Mitigation Plan Update
64 DATE OF DISASTER TYPE OF DISASTER COUNTIES INVOLVED
October 10, 2019 Wildfires (Eagle, Sandalwood,
Reche, and Wolf fires)
Riverside
August 2018 Wildfire (Holy Fire) Orange and Riverside
July 2018 Wildfires (Cranston & Carr Fire) Riverside and Shasta August 7, 2013 Wildfire (Silver Fire) Riverside
July 15, 2013 Wildfire (Mountain Fire) Riverside
November 2008 Wildfires Los Angeles, Orange, Riverside, San Bernardino, Santa Barbara
October 21, 2007 Wildfires Los Angeles, Orange, Riverside, San Bernardino, San Diego, Santa Barbara,
Ventura
October 2006 Wildfire Riverside
October – November 2003 Wildfires Los Angeles, Riverside, San Bernardino, San Diego, Ventura
October 27 & 28, 1993 Firestorms Los Angeles, Orange, Riverside, San Bernardino, San Diego, Ventura
List of Governor-declared disasters for property tax purposes since 1991. Source: California State Board of Equalization Cathedral City’s fire history has been shaped by urban structure fires, transportation-related fire hazards, and indirect wildfire exposure. Although the city is not classified within a Very High Fire Hazard Severity Zone (VHFHSZ), its proximity to the Santa Rosa and San Jacinto Mountains, extensive commercial activity, and major transportation corridors contribute to significant fire risks Between 1984 and 2021, no major wildfire incidents have been officially recorded within Cathedral City’s boundaries. However, the city has periodically been affected by wildfire smoke, ember transport, and emergency response efforts linked to regional wildfires. • 2020 Wildfire Smoke and Air Quality Emergency: During the September 2020 wildfire season, Cathedral City experienced hazardous air quality conditions due to smoke from wildfires across Southern California. The AQI (Air Quality Index) exceeded 200 ("Very Unhealthy"), prompting public health advisories, school closures, and emergency responses. Wildfire smoke transported from fires in San Bernardino National Forest, the San Jacinto Mountains, and other regions led to an increase in emergency room visits for respiratory distress. • Power Line Fire near Interstate 10 (2021): In July 2021, a utility-related fire occurred near Interstate 10, igniting dry brush along the freeway embankment. High temperatures and dry conditions contributed to the rapid spread of the fire, which temporarily disrupted traffic and required emergency fire suppression efforts. This incident underscored the ongoing risk of electrical infrastructure failures as ignition sources, particularly during the peak summer fire season.

Local Hazard Mitigation Plan Update
65 While Cathedral City has not experienced major wildfires within city limits, it is periodically affected by wind-driven embers from fires in surrounding mountainous areas. Santa Ana wind events have the potential to carry embers from fires burning in Riverside County, the San Bernardino National Forest, and the Santa Rosa Mountains into Cathedral City, where they could ignite dry vegetation, rooftops, and flammable storage areas.

Nearby FEMA Disaster Declarations Related to Fire Hazards While Cathedral City has not been the direct recipient of a FEMA fire-related disaster declaration, several regional disaster declarations have impacted the city due to wildfire smoke, ember transport, and emergency response coordination.
• FEMA DR-4569-CA (October 2020 – Regional Wildfires, including Bobcat Fire and El Dorado Fire): This federal disaster declaration covered major wildfires in Southern California, including the Bobcat Fire in Los Angeles County and the El Dorado Fire in San Bernardino County. Cathedral City was not directly in the burn zone but experienced severe smoke pollution and degraded air quality, prompting health advisories and emergency response measures
• FEMA DR-5285-CA (September 2022 – Statewide Wildfires and Smoke Impacts): This declaration covered multiple large-scale wildfires across California, including the Fairview Fire and Mosquito Fire. During this period, wildfire smoke caused AQI levels in Cathedral City to deteriorate to "Unhealthy" (AQI 150-200) for multiple days, leading to increased health risks, disruptions to outdoor activities, and increased hospital visits for respiratory illnesses. Although Cathedral City did not receive direct federal assistance, regional disaster funding supported firefighting operations and emergency air quality monitoring in Riverside County.

Probability and Effects of Future Fire Conditions
Overall probability over next five years: Likely.

Urban fire risk in Cathedral City is influenced by commercial density, electrical infrastructure vulnerabilities, and transportation-related fire hazards. The probability of significant fire events remains moderate to high due to aging electrical systems, commercial storage of flammable materials, and increased energy demand. In particular, commercial and mixed-use zones with older buildings lacking modern fire suppression systems present a higher risk of structural fire spread.

Local Hazard Mitigation Plan Update
66 While Cathedral City is not located within a Very High Fire Hazard Severity Zone (VHFHSZ), over 6,092 properties-approximately 30% of all properties in the city-have some level of wildfire risk over the next 30 years. These risks stem from heat-induced ignitions, ember transport, and prolonged drought conditions that create more flammable landscapes.

Urban fire risk in Cathedral City is expected to increase in severity, particularly in high-risk commercial areas where hazardous materials and aging electrical infrastructure increase fire ignition potential. Power grid failures, mechanical malfunctions, and electrical faults are projected to become more frequent as extreme heat events increase energy demand.

Fire intensity is expected to rise, with large-scale commercial fires, classified as Class 3 or higher on the Fire Intensity Scale (FIS), becoming more severe in cases involving flammable chemicals, plastics, or fuel storage. Without proactive mitigation measures, urban fires could result in higher property losses and greater demands on emergency response resources.

Wildfire risk in Cathedral City is expected to grow due to rising temperatures, prolonged drought, and stronger wind events. The number of extreme wildfire days-defined by temperatures exceeding 100°F, humidity below 15%, and winds greater than 40 mph-is projected to increase by 30-50% by 2050.

Santa Ana wind conditions are expected to persist for longer periods each season, increasing by approximately 10-15%, which will further elevate the risk of wind-driven fire spread affecting urban areas. Reduced regional fuel moisture levels due to persistent droughts will contribute to larger, more intense wildfires, indirectly impacting Cathedral City through wildfire smoke, air quality deterioration, and transportation disruptions.

While Cathedral City does not face direct wildfire exposure, it is vulnerable to wind-driven ember transport from regional wildfires in the Santa Rosa and San Jacinto Mountains. Santa Ana winds reaching speeds of 40-80 mph could carry embers into urban areas, igniting dry vegetation, rooftops, and industrial storage materials.

Wildfire smoke remains a persistent hazard, with air quality frequently deteriorating during major fire events. AQI levels exceeding 150 ("Unhealthy") have been recorded multiple times in Cathedral City due to wildfire smoke transport from surrounding regions. Projections suggest that AQI levels exceeding 200 ("Very Unhealthy") may occur annually by 2050, necessitating expanded public health protections, enhanced air filtration measures, and emergency response planning for prolonged smoke exposure.

Local Hazard Mitigation Plan Update
67 3.3.4 Power Outage
Description
A power outage, also known as an electrical blackout or power failure, is the loss of electrical service to a given area due to disruptions in the generation, transmission, or distribution of electricity. Outages may be localized, affecting a small area or facility, or widespread, impacting entire regions for extended periods. The severity of an outage depends on its duration, geographic extent, and the ability of electrical utilities to restore power. Cathedral City’s reliance on commercial activities, emergency services, and extreme heat mitigation measures makes power reliability a key concern.

Power outages in Cathedral City can occur in three primary forms, each with distinct implications:
• Momentary interruptions, lasting seconds to minutes, typically occur due to automatic grid protection systems responding to minor faults, such as tree branches contacting power lines or short circuits. These brief outages can disrupt traffic signals, industrial equipment, and business operations.
• Sustained outages, lasting minutes to hours, often result from localized equipment failures, transformer malfunctions, or downed power lines. Such outages cause disruptions to traffic flow, emergency response systems, and residential air conditioning units, particularly during extreme heat.
• Extended blackouts, lasting multiple hours to days or even weeks, are often caused by major disasters such as earthquakes, extreme wind events, or regional grid failures. Prolonged outages Local Hazard Mitigation Plan Update
68 have severe implications for hospitals, water treatment plants, communication networks, and cooling infrastructure.

Cathedral City’s electrical infrastructure is vulnerable to multiple outage triggers, including weatherrelated events, infrastructure failures, and human-caused disruptions. • Extreme Heat and Grid Overload: Cathedral City experiences high temperatures exceeding 120°F during summer months, increasing electricity demand for air conditioning and industrial cooling systems. Overloaded infrastructure can lead to rolling blackouts or brownouts, particularly between July and September. As the number of days exceeding 111°F is expected to increase from 7 days in 1990 to over 32 days per year by 2050, power grid strain will become more severe.
• Santa Ana Winds and Storm Events: Wind gusts exceeding 50 mph can topple power lines, damage transformers, and cause airborne debris to strike electrical equipment, increasing the risk of outages. Santa Ana winds also heighten wildfire risks, and Southern California Edison (SCE) may preemptively shut off power through Public Safety Power Shutoffs (PSPS) to prevent utility-related ignitions.
• Earthquakes and Seismic Damage: A major earthquake could disrupt power supply by damaging substations, transmission lines, and underground electrical conduits. A large-scale seismic event could cause cascading failures, impacting critical emergency response capabilities, water treatment operations, and cooling centers.
• Vehicle Collisions and Equipment Failures: Given Cathedral City’s proximity to major transportation corridors such as Interstate 10 and Highway 111, the risk of vehicular collisions damaging power poles or substations is elevated. Additionally, aging electrical infrastructure presents reliability concerns, particularly during periods of peak demand or extreme weather. • Cyberattacks and Physical Security Threats: As part of Southern California’s regional power grid, Cathedral City relies on digitally connected electrical systems that could be targeted by cyberattacks. Intentional disruptions to substations or grid control centers could cause widespread outages.

Utility-initiated Public Safety Power Shutoffs (PSPS) add another layer of complexity to Cathedral City’s power reliability. Southern California Edison (SCE) may preemptively shut off power to reduce wildfire ignition risks during high wind and dry conditions. While Cathedral City is not within a designated high wildfire risk zone, PSPS events in adjacent areas may still affect power supply, disrupting businesses, schools, and vulnerable residents.

Location and Geographic Extent
Local Hazard Mitigation Plan Update
69 Power outages in Cathedral City can occur citywide but have a higher probability and greater consequences in specific locations due to infrastructure vulnerabilities, land use patterns, and population density.

Cathedral City has a significant concentration of commercial and light industrial facilities, particularly along East Palm Canyon Drive, Date Palm Drive, and Highway 111. These areas rely heavily on uninterrupted power for refrigeration, automated processing, and retail operations. Extended blackouts can disrupt business continuity, result in financial losses, and impact emergency services.

Residential neighborhoods, particularly mobile home parks, senior housing complexes, and highdensity apartments, face elevated risks during power outages, especially during extreme heat events.

Many low-income households lack backup power sources, making them vulnerable to heat-related illnesses. Air conditioning failures during power outages in summer months pose significant public health risks, particularly in areas where temperatures can exceed 120°F.

Key transportation corridors such as Interstate 10, Date Palm Drive, and Ramon Road depend on functional traffic signals and street lighting, which can become non-operational during power failures.

Public safety services, including fire stations, police departments, and hospitals, rely on backup generators, but prolonged outages could strain these emergency resources.

Relationship to Land Use and Development
As new development occurs and energy demand rises, mitigating power outage risks will require proactive planning and grid modernization. Cathedral City’s growing commercial and residential sectors are increasing electricity demand, placing additional strain on existing electrical infrastructure.

The expanding logistics, retail, and hospitality sectors require consistent, high-capacity power sources.

Without grid upgrades and backup power systems, outages could lead to business disruptions, production losses, and economic instability.

Magnitude and Severity
Unlike natural hazards that have well-defined measurement scales (e.g., the Modified Mercalli Intensity Scale for earthquakes or the Saffir-Simpson Scale for hurricanes), power outages are categorized based on their geographic scope, duration, and cascading effects. While momentary service interruptions are common, prolonged and widespread outages can have severe consequences for public health, emergency response, industrial operations, and economic stability.

Outage Scope and Geographic Extent – U.S. Department of Energy (DOE) Classification Local Hazard Mitigation Plan Update
70 The U.S. Department of Energy (DOE) classifies power outages based on the number of customers affected and the extent of grid failure:
• Localized Outage (Level 1): Affects a single building, block, or small neighborhood due to equipment failure, minor weather impacts, or scheduled maintenance. Typically lasts under two hours and has minimal community-wide impacts.
• Substation-Level Outage (Level 2): Impacts hundreds to thousands of customers due to transformer failures, high wind damage to power lines, or extreme heat grid stress. Outages last a few hours to a full day, affecting traffic signals, businesses, and emergency services. • Citywide or Regional Outage (Level 3): Affects tens of thousands of customers due to major transmission failures, wildfire-related public safety power shutoffs (PSPS), or severe storms.

Lasts several hours to multiple days, causing significant economic and emergency response impacts.
• Grid Failure or Blackout (Level 4): A widespread, prolonged outage affecting multiple cities, counties, or states, often caused by major weather disasters, earthquakes, or cyberattacks. Can last weeks, leading to severe economic losses, public health emergencies, and security concerns.

Cathedral City most frequently experiences Level 1 and Level 2 outages, though Level 3 outages have occurred during extreme weather events and regional grid failures.

Outage Duration and Restoration Complexity – IEEE 1366 Reliability Indices The Institute of Electrical and Electronics Engineers (IEEE) Standard 1366 provides reliability indices to measure the frequency and duration of power outages. These indices help utilities and emergency planners assess service reliability and outage severity:
• System Average Interruption Duration Index (SAIDI): Measures total annual power outage duration per customer. In Cathedral City, SAIDI has historically ranged from 60 to 120 minutes per year, though this increases significantly during heat waves and high-wind events. • System Average Interruption Frequency Index (SAIFI): Measures how often the average customer experiences an outage per year. In Cathedral City, SAIFI values suggest 1-2 outages per year under normal conditions, with higher frequencies during peak summer months. • Customer Average Interruption Duration Index (CAIDI): Evaluates the average time to restore power after an outage. CAIDI in Cathedral City is typically under 90 minutes but can increase significantly during extreme weather or seismic events.

Local Hazard Mitigation Plan Update
71 Severity of Power Outages
The severity of a power outage depends on its duration, the number of customers impacted, and cascading effects on critical infrastructure. Outages range from minor disruptions to large-scale emergencies.
• Short-Term Outages (Less than 2 hours – Low Severity): Short-term outages are the most common in Cathedral City and are typically caused by localized transformer failures, minor equipment malfunctions, or temporary weather-related disruptions. While these outages cause minimal long-term impacts, they can disrupt traffic signals, interfere with business operations, and create safety concerns for residents reliant on medical equipment. • Medium-Term Outages (2 to 12 hours – Moderate Severity): Outages lasting several hours are often due to heat-related grid overloads, vehicle collisions with power infrastructure, or downed power lines from wind events. These outages increase risks such as:
o Traffic congestion and increased accident risk due to non-functioning traffic lights. o Business closures and financial losses, especially for restaurants, grocery stores, and industrial facilities relying on continuous power.
o Medical risks for individuals dependent on electricity-powered medical devices, particularly in high-temperature conditions.
• Long-Term Outages (12 hours to multiple days – High Severity): Extended outages, typically caused by severe storms, wildfires, or regional grid failures, result in widespread impacts such as:
o Loss of refrigeration for food and medication, increasing health risks for vulnerable populations.
o Emergency service delays, including 911 call center disruptions and decreased police/fire response efficiency.
o Shutdowns of water and wastewater treatment facilities if backup generators fail, leading to public health risks. Should this section include impacts if outages occur during summer months – added threat of heat exposure, deaths? o Catastrophic Power Outages (Multiple Days to Weeks – Extreme Severity): A catastrophic, prolonged power outage-such as one caused by a major earthquake, cyberattack, or statewide grid failure-could create a widespread humanitarian and economic crisis. In such cases:
o Hospitals and emergency services would rely solely on backup generators, which could fail if fuel supplies run out.
o Mass evacuations may be necessary if essential services such as water, fuel, and communication systems become inoperable.

Local Hazard Mitigation Plan Update
72 o The financial impact on businesses, particularly in the industrial sector, could result in millions of dollars in losses due to production stoppages, supply chain failures, and perishable inventory losses.

Historical Occurrences of Power Outages
FEMA Disaster Declarations
Incident
Subcategory County FEMA Declaration String
Calendar Year of
Declaration
Date
Month
Declaration
Date
Declaration
Title State
None None None None None None None None
California Governor-declared Declarations

DATE OF DISASTER TYPE OF DISASTER COUNTIES INVOLVED
None None None
List of Governor-declared disasters for property tax purposes since 1991. Source: California State Board of Equalization Cathedral City has experienced multiple power outages over the past two decades due to extreme heat, high winds, equipment failures, and regional grid instability. Power outages have occurred during heatwaves, storms, and Public Safety Power Shutoffs (PSPS) implemented to reduce wildfire risk. • July 2006 California Heatwave Power Outages: In July 2006, California experienced one of its most severe heatwaves, resulting in record-breaking temperatures that overwhelmed the power grid. Cathedral City, like other parts of Riverside County, faced rolling blackouts lasting between two to six hours. The outages affected residences, businesses, and industrial zones, particularly straining air conditioning systems, transformers, and substations. • December 2011 Santa Ana Windstorm and Power Failures: A Santa Ana wind event in December 2011 brought gusts exceeding 80 mph, toppling power lines, damaging transmission infrastructure, and causing widespread outages. The event left thousands of residents and businesses in Cathedral City and surrounding areas without electricity for several days. The power failure also resulted in traffic signal failures, increased accident risks, and business disruptions.
• September 2015 Heatwave and Grid Overloads: In September 2015, a late-summer heatwave caused local power failures across Riverside County, including Cathedral City. With temperatures exceeding 105°F, transformers in residential and commercial districts failed, Local Hazard Mitigation Plan Update
73 causing outages that lasted between four to eight hours. Businesses and residents reliant on air conditioning and refrigeration systems were significantly impacted. • July 2018 Southern California Power Grid Strain: A statewide heatwave in July 2018 caused emergency grid conditions, forcing rolling blackouts in Cathedral City and other parts of Riverside County. Outages lasted between one to three hours, affecting residential areas, commercial corridors, and industrial facilities. Large industrial users were required to reduce energy consumption, leading to temporary production slowdowns. • January 2023 California Winter Storm and Power Outages: In early 2023, a series of atmospheric river storms brought high winds, heavy rain, and flooding to Southern California, including Cathedral City. Wind speeds exceeding 50 mph damaged power lines and transformers, leading to outages that lasted up to 48 hours in some industrial districts.

FEMA Disaster Declarations Related to Power Outages
While power outages alone do not typically trigger standalone FEMA disaster declarations, they often occur as secondary impacts of federally declared disasters such as extreme heat, wildfires, and highwind events. Cathedral City has been affected by several FEMA disaster declarations linked to major power failures.
• FEMA DR-4301-CA (February 2017 – Winter Storms and Infrastructure Damage): Severe winter storms caused flooding, high winds, and power outages across Southern California, including Cathedral City. Localized outages resulted from downed power lines and waterdamaged electrical equipment. FEMA assistance was provided for public infrastructure repairs, including electrical system restoration.
• FEMA DR-4569-CA (October 2020 – Wildfires and PSPS Events): During California’s devastating 2020 wildfire season, utility companies implemented Public Safety Power Shutoffs (PSPS) to mitigate fire risks. While Cathedral City was not directly impacted by wildfires, PSPS events disrupted portions of the regional electrical grid, leading to brief power interruptions in industrial zones.
• FEMA DR-4683-CA (January 2023 – Winter Storm Power Failures): A series of atmospheric river storms caused flooding, landslides, and power failures across Southern California.

Cathedral City experienced extended power outages in some industrial districts as a result of high winds damaging electrical infrastructure.

Probability and Effects of Future Conditions
Overall probability over next five years: Likely.

Local Hazard Mitigation Plan Update
74 Cathedral City is projected to experience an increase in both the frequency and severity of power outages due to rising energy demand, climate change impacts, and vulnerabilities in aging electrical infrastructure. While short-term, localized outages will continue to result from equipment failures and minor weather disturbances, the likelihood of prolonged and widespread blackouts is growing. Extreme heat events, high windstorms, seismic activity, and cyber or physical attacks on power infrastructure all contribute to this increasing risk.

Risk assessments for power outages rely on historical outage data, climate projections, and grid reliability modeling. As part of Southern California Edison’s (SCE) service territory and the California Independent System Operator (CAISO) power grid, Cathedral City is subject to forecasts by CAISO, the U.S. Department of Energy (DOE), and the North American Electric Reliability Corporation (NERC), which track grid stability, energy demand trends, and outage risks.

Cathedral City is located in a seismically active region, making its electrical infrastructure highly susceptible to earthquake-related damage. A magnitude 6.5 or greater earthquake on the San Andreas or San Jacinto faults could result in severe disruptions to substations, high-voltage transmission lines, and underground power conduits. Restoration efforts following a major earthquake could extend for several days or weeks, depending on the extent of damage to infrastructure and available repair resources.

Climate models predict that rising temperatures, prolonged heatwaves, and more intense storms will significantly impact electrical grid stability. By 2050, the number of extreme heat days exceeding 95°F in Cathedral City is projected to double, leading to an estimated 30% increase in heat-related grid overloads. The frequency of rolling blackouts is expected to rise as electricity demand peaks during extreme weather events. Additionally, Santa Ana wind events, a leading cause of power line damage, are anticipated to become more intense due to climate change, increasing the probability of winddriven outages. High wind events can topple power lines, damage transformers, and disrupt transmission infrastructure, especially in areas with overhead electrical lines.

By 2045, CAISO projects that peak electricity demand in Southern California will increase by 25–30%, raising the likelihood of power shortages during heatwaves. If renewable energy generation and grid modernization efforts fail to keep pace, rolling blackouts could become an annual occurrence during extreme heat periods. Businesses and industrial facilities may face significant economic impacts, with extended power outages potentially resulting in annual losses ranging from $5 million to $10 million due to production delays, business closures, and supply chain disruptions.

Local Hazard Mitigation Plan Update
75 PSPS events, which preemptively cut power to reduce wildfire risks, are expected to increase in both duration and geographic coverage by 2030. While Cathedral City may not face direct wildfire threats, regional power disruptions could have widespread economic consequences, affecting businesses, schools, hospitals, and emergency response systems.

Cybersecurity threats to electrical infrastructure are projected to rise significantly in the coming decades. National security assessments estimate that by 2040, the probability of a major cyberattack affecting the power grid will increase by 50%. Additionally, physical attacks on substations, similar to those previously carried out in California, could lead to localized or widespread power failures.

3.3.5 Earthquake
Description
An earthquake is a sudden and violent shaking of the ground caused by the release of energy within the Earth's crust due to movement along fault lines. This energy release generates seismic waves that propagate outward, resulting in ground shaking, surface rupture, soil liquefaction, landslides, and, in some cases, tsunamis. Earthquakes vary in magnitude, depth, and duration, with impacts ranging from minor tremors to catastrophic destruction. Their severity depends on factors such as the amount of energy released, proximity to the epicenter, depth of the seismic activity, and local geological conditions. Because seismic events occur without warning, they are among the most unpredictable and destructive natural hazards.

Cathedral City is located within a highly seismically active region of Southern California, primarily influenced by the southern segment of the San Andreas Fault Zone, which is capable of generating magnitude 8.0+ earthquakes. The San Jacinto Fault Zone, located west of the city, also presents a Local Hazard Mitigation Plan Update
76 significant seismic hazard and has historically been the source of multiple moderate-to-large earthquakes. Additional faults that may impact Cathedral City include the Pinto Mountain Fault, the Burnt Mountain Fault, and the Elsinore Fault, all of which are capable of producing strong ground shaking.

The Banning Fault, a branch of the San Andreas system, runs across the northern portion of the planning area and is capable of producing a magnitude 7.4 earthquake, which could generate peak ground accelerations of 0.45 to 0.9g in Cathedral City. The Mission Creek Fault, another strand of the San Andreas Fault, could generate peak accelerations of 0.4 to 0.8g, with the potential for even greater accelerations if simultaneous rupture of multiple fault strands occurs.

The majority of earthquakes affecting Cathedral City result from tectonic activity along strike-slip faults, where plates move laterally against one another. The San Andreas Fault and its subsidiary faults define the boundary between the Pacific Plate and the North American Plate, making the region particularly prone to strong seismic events.

Human activities such as groundwater extraction, oil and gas production, and geothermal energy development can also trigger seismic activity. In areas of the Coachella Valley, subsurface fluid withdrawal has been linked to minor induced seismicity, though it is not the primary source of earthquake risk.

Secondary Effects of Earthquakes
Ground Shaking: Cathedral City is subject to severe ground shaking during large earthquakes. The valley floor consists of loose, recently deposited sediments, which amplify seismic waves, increasing the likelihood of structural damage.

Surface Rupture: If an earthquake occurs along a shallow fault, ground displacement may damage roads, pipelines, and buildings. The Banning Fault and Mission Creek Fault, which pass through Cathedral City’s planning area, have the potential for surface rupture during a significant seismic event.

Liquefaction: Liquefaction occurs when loose, saturated soils temporarily lose strength and behave like a liquid due to strong shaking. While the potential for liquefaction is low to none throughout most of Cathedral City, certain areas near the northern portion of the planning area, particularly near the San Andreas Fault, have a moderate to high susceptibility due to shallow groundwater levels.

Local Hazard Mitigation Plan Update
77 Seismically Induced Settlement: The valley floor consists of unconsolidated sediments that are highly susceptible to settlement, which can damage buildings, pipelines, and grade-sensitive infrastructure.

Developers in high-risk areas should conduct subsurface geotechnical investigations to evaluate settlement risks and implement mitigation measures such as soil densification.

Landslides and Slope Instability: Seismically induced landslides and rockfalls pose a risk in the Santa Rosa Mountains and Indio Hills, particularly where steep terrain and fractured rock formations exist.

Ground accelerations exceeding 0.10g in these areas could trigger slope failures, potentially impacting roadways, homes, and utilities.

Fire Following Earthquakes: Broken gas lines and electrical failures can ignite post-earthquake fires, a significant concern in densely built urban areas. If fire suppression capabilities are impaired due to water main breaks or blocked roadways, fire hazards could escalate quickly.

Location and Geographic Extent
Local Hazard Mitigation Plan Update
78 Cathedral City is located in a seismically active region of Southern California and is at significant risk of earthquakes due to its proximity to several major fault systems. The city is situated within Riverside County, an area classified as having high seismic hazard potential. Multiple active faults in the vicinity are capable of generating moderate to severe earthquakes that could result in strong ground shaking, structural damage, and secondary hazards such as liquefaction and landslides.

Key fault systems that influence Cathedral City’s seismic risk include:
• San Andreas Fault – The San Andreas Fault is the most significant seismic threat to Cathedral City. This right-lateral strike-slip fault extends through the Coachella Valley and is capable of producing earthquakes exceeding magnitude 8.0. A major rupture of the southern segment of the San Andreas Fault could result in violent shaking, widespread infrastructure damage, and significant disruptions to critical lifelines such as freeways, power lines, and aqueducts. • San Jacinto Fault – The San Jacinto Fault, which runs through Riverside County, has a history of producing moderate to large earthquakes. This fault is capable of generating magnitude 7.0 earthquakes, with shaking intensities strong enough to cause significant structural damage.

Local Hazard Mitigation Plan Update
79 • Banning Fault – A segment of the San Andreas Fault system, the Banning Fault extends near Cathedral City and presents a risk of moderate-to-large earthquakes. Ground shaking from this fault could cause structural damage and disrupt transportation networks. • Elsinore Fault – Though farther west, the Elsinore Fault has the potential to generate magnitude

7.1 earthquakes. While its impact on Cathedral City would be less severe than the San Andreas or San Jacinto Faults, it could still contribute to regional seismic activity The California Geological Survey (CGS) and U.S. Geological Survey (USGS) have identified Cathedral City as an area with a moderate-to-high risk of liquefaction, particularly in the northern portion of the city near the San Andreas Fault. Liquefaction occurs when loose, water-saturated soils lose their strength during an earthquake, potentially causing buildings, roads, and underground utilities to sink or tilt.

Relationship to Land Use and Development
Cathedral City has a mix of residential, commercial, and industrial development, all of which have varying levels of vulnerability to seismic hazards. The city’s land use and development patterns influence its overall risk exposure and the extent of potential earthquake damage.

Residential Areas: Many of Cathedral City’s residential neighborhoods contain a mix of single-family homes and multi-family units. Structures built before California's modern seismic codes (introduced in the 1970s) may be particularly vulnerable to damage. Homes with unreinforced masonry, soft-story designs, or older foundations are at greater risk of collapse or severe structural damage during strong ground shaking.

Commercial and Industrial Zones: Cathedral City has several commercial and industrial districts that house a variety of businesses, including retail centers, hotels, and light manufacturing facilities. These areas contain critical infrastructure such as power substations, water treatment plants, and major roadways. Unreinforced masonry buildings, non-ductile concrete structures, and older industrial facilities are particularly susceptible to earthquake damage, potentially leading to hazardous materials spills, business disruptions, and supply chain interruptions.

Critical Infrastructure and Public Facilities: Several critical infrastructure systems in Cathedral City could be severely impacted by a major earthquake, including:

Local Hazard Mitigation Plan Update
80 • Water and Sewer Systems: Underground water mains and sewer lines are vulnerable to rupture during earthquakes. Damage to these systems could disrupt water supply and wastewater treatment operations.
• Electric and Natural Gas Utilities: Cathedral City is served by Southern California Edison (SCE) for electricity and Southern California Gas Company for natural gas. Earthquakes could damage substations, transmission lines, and pipelines, increasing the risk of prolonged power outages and gas leaks.
• Transportation Networks: Key transportation routes, including Interstate 10, Date Palm Drive, and East Palm Canyon Drive (State Route 111), are essential for emergency response and economic activity. An earthquake could cause road damage, bridge collapses, and traffic congestion, severely affecting mobility within and beyond the city.

Cathedral City has several areas susceptible to liquefaction, particularly in the northern portion of the city near the San Andreas Fault. The California Geological Survey classifies this area as having moderate to high liquefaction potential, due to shallow groundwater levels and unconsolidated sandy soils.

Liquefaction can cause severe ground instability, structural collapse, and damage to underground utilities.

By contrast, the southern portion of Cathedral City, near the Santa Rosa Mountains, has a low risk of liquefaction due to deeper groundwater levels and coarser sediments such as gravel, cobbles, and boulders. However, this area is more vulnerable to seismically induced landslides, particularly where steep slopes exist.

Seismically Induced Settlement is another concern for Cathedral City, particularly in areas where loose, recently deposited sediments are present. Strong ground shaking can cause soils to compact, leading to uneven settlement of buildings, pipelines, and roadways. Proper foundation design, soil compaction, and geotechnical investigations are critical in mitigating these risks.

Magnitude and Severity
Earthquake severity is measured using two primary scales: magnitude, which quantifies the energy released at the earthquake’s source, and intensity, which describes the observed effects on people, structures, and the environment at different locations.

The Moment Magnitude Scale (Mw) is the most widely used measure of earthquake size, replacing the older Richter Scale. It quantifies the total energy released by an earthquake by considering fault length, slip amount, and rock rigidity. The Richter Scale, developed in 1935, assigns a logarithmic magnitude value to seismic events, where each whole-number increase represents a tenfold increase in amplitude and approximately 32 times more energy release.

Local Hazard Mitigation Plan Update
81 Magnitude Classifications:
• Minor (Mw <3.0) – Generally not felt but recorded by seismographs. • Light (Mw 3.0–4.9) – Often felt but rarely causes damage. • Moderate (Mw 5.0–5.9) – Can cause damage to poorly built structures. • Strong (Mw 6.0–6.9) – Can cause widespread damage, particularly near the epicenter. • Major (Mw 7.0–7.9) – Causes significant destruction over a large area. • Great (Mw 8.0+) – Capable of catastrophic damage and widespread impact.

The Modified Mercalli Intensity (MMI) Scale categorizes earthquakes based on their observed effects on people, buildings, and natural features. It is measured on a Roman numeral scale from I (Not Felt) to XII (Total Destruction). Unlike magnitude, which remains constant for a given earthquake, MMI values vary by location based on distance from the epicenter, soil composition, and building vulnerability.

Intensity Levels:
• I – Instrumental: Not felt except by very sensitive instruments. • IV – Light: Felt indoors by many, outdoors by few; no damage. • VII – Very Strong: Noticeable damage to buildings; furniture overturned. • IX – Violent: Severe damage, some buildings collapse. • XII – Catastrophic: Total destruction; ground movement visible.

Cathedral City faces a high risk of strong ground shaking due to its proximity to the San Andreas Fault, the San Jacinto Fault Zone, and the Pinto Mountain Fault. Based on USGS ShakeMap projections, a magnitude 7.0–8.0 earthquake on the San Andreas Fault could generate Modified Mercalli Intensity (MMI) IX (Violent) to MMI X (Extreme) shaking in Cathedral City. This level of seismic intensity could lead to severe infrastructure damage, widespread power outages, ruptured water and gas pipelines increasing fire risks, and liquefaction hazards in areas with water-saturated soils, particularly in lowlying and industrial zones.

Historical Occurrences
FEMA Disaster Declarations
Incident
Subcategory County
FEMA
Declaration
String
Calendar
Year of
Declaration
Date
Month
Declaration
Date Declaration Title State
Earthquake Riverside
County DR-845-CA 1990 April 4/6/1990 EARTHQUAKE CA
Local Hazard Mitigation Plan Update
82 Incident
Subcategory County
FEMA
Declaration
String
Calendar
Year of
Declaration
Date
Month
Declaration
Date Declaration Title State
Earthquake Riverside
County DR-1008-CA 1994 January 1/17/1994 NORTHRIDGE EARTHQUAKE CA Earthquake Riverside
County DR-1577-CA 2005 February 2/4/2005

SEVERE STORMS, FLOODING,

DEBRIS FLOWS, AND
MUDSLIDES*
CA
Earthquake Riverside
County DR-4301-CA 2017 February 2/14/2017

SEVERE WINTER STORMS,

FLOODING, MUDSLIDES, DEBRIS
FLOWS*
CA
California Governor-declared Declarations

DATE OF DISASTER TYPE OF DISASTER COUNTIES INVOLVED
June 28, 1992 Earthquakes Riverside, San Bernardino
List of Governor-declared disasters for property tax purposes since 1991. Source: California State Board of Equalization Cathedral City is situated in one of the most seismically active regions in the United States, with a history of moderate to strong earthquakes impacting the Coachella Valley and surrounding areas. Due to its location near major fault systems, the city remains vulnerable to significant seismic events. Several notable earthquakes have affected the region:
1992 Landers Earthquake (Magnitude 7.3)
• Date: June 28, 1992
• Epicenter: Landers, approximately 50 miles northeast of Cathedral City • Impacts: Strong shaking caused structural damage to buildings and roads throughout Riverside and San Bernardino counties
• Economic Losses: Estimated at $92 million
• FEMA Major Disaster Declaration: DR-937-CA.
1992 Big Bear Earthquake (Magnitude 6.5)
• Date: June 28, 1992 (same day as Landers earthquake)
• Epicenter: Big Bear, California
• Impacts: Additional structural damage across Southern California, secondary impacts in Coachella Valley
• FEMA Major Disaster Declaration: DR-937-CA.
1999 Hector Mine Earthquake (Magnitude 7.1)
Local Hazard Mitigation Plan Update
83 • Date: October 16, 1999
• Epicenter: Mojave Desert, California
• Impacts: Felt across Cathedral City, moderate damage to roads and structures in nearby desert regions but limited direct impact to the city.

2010 Mexicali Earthquake (Magnitude 7.2)
• Date: April 4, 2010
• Epicenter: Baja California, Mexico, near the U.S. border • Impacts: Strong shaking felt throughout Southern California, including Cathedral City; moderate infrastructure damage in Imperial County, California.

Probability and Effects of Future Conditions
Overall probability over next five years: Moderate.

Seismic risk in Cathedral City is assessed using Probabilistic Seismic Hazard Analysis (PSHA), which estimates the likelihood of various levels of ground shaking over time. The United States Geological Survey (USGS) and the California Geological Survey (CGS) provide earthquake probability models based on historical seismic activity, fault slip rates, and regional geologic conditions.

The 2024 Uniform California Earthquake Rupture Forecast (UCERF3) estimates a 72% probability of a magnitude 6.7 or greater earthquake in Southern California within the next 30 years. The most significant earthquake risks to Cathedral City come from the San Andreas Fault, the San Jacinto Fault Zone, and the Banning Fault. The Coachella Valley segment of the San Andreas Fault, which runs directly through the northern portion of Cathedral City, has the potential to generate earthquakes ranging from magnitude 7.0 to 8.3. A rupture of this fault could cause violent ground shaking (Modified Mercalli Intensity X–XII), resulting in severe damage to buildings, infrastructure, and transportation networks.

The San Jacinto Fault Zone, located west of Cathedral City, has historically experienced moderate-tolarge earthquakes, including a magnitude 7.0 event. This fault exhibits strain accumulation, indicating a heightened probability of seismic activity in the near future. The Banning Fault, which crosses Cathedral City’s planning area, has the potential to generate a magnitude 7.4 earthquake, capable of producing peak ground accelerations between 0.45g and 0.9g, leading to severe infrastructure damage.

Local Hazard Mitigation Plan Update
84 Seismic intensity maps classify Cathedral City as a high-risk zone for strong ground motion, particularly in areas with loose alluvial soils near the San Andreas Fault and Banning Fault. Liquefaction modeling from the California Geological Survey (CGS) identifies portions of the city, especially in the northern planning area, as highly susceptible to ground failure due to shallow groundwater and unconsolidated sediments. During strong shaking, these conditions could lead to soil liquefaction, resulting in building collapses, road failures, and utility line disruptions.

Recent geophysical studies suggest that multi-fault ruptures-where multiple faults rupture simultaneously-are more common than previously thought. If the San Andreas Fault and San Jacinto Fault rupture together, the resulting earthquake could exceed magnitude 8.0, causing catastrophic regional damage and prolonged recovery periods.

Impacts of Future Earthquakes
• Structural Damage: Many industrial and commercial structures in Cathedral City were built before modern seismic building codes were adopted. Older buildings, particularly unreinforced masonry structures and pre-1970s tilt-up concrete buildings, face a higher probability of structural failure during a significant earthquake.
• Transportation and Infrastructure Disruptions: A magnitude 7.5+ earthquake could cause severe damage to Interstate 10, State Route 111, bridges, and overpasses, impeding emergency response and evacuation efforts.
• Water and Utility Failures: The city’s water distribution system and natural gas pipelines are vulnerable to rupture during seismic events, increasing the risk of post-earthquake fires and prolonged service disruptions.
• Economic and Social Disruptions: A major earthquake could lead to significant economic losses, business closures, and displacement of residents, particularly in mobile home parks and highdensity housing units.

While climate change does not directly cause earthquakes, it can exacerbate secondary seismic hazards such as landslides and post-seismic flooding. Prolonged drought conditions can lead to soil instability, increasing the likelihood of seismically induced landslides on steep slopes in and around Cathedral City. Additionally, intense atmospheric river storms projected to increase with climate change may contribute to post-earthquake flooding, further complicating emergency response efforts.

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85 (this page intentionally left blank)

Local Hazard Mitigation Plan Update
86 3.3.6 Flooding
Description
Flooding in Cathedral City results from a combination of heavy precipitation, stormwater runoff, infrastructure limitations, and drainage system failures. The city’s location in the Coachella Valley, along with its proximity to the Whitewater River and surrounding mountainous terrain, significantly influences its flood risk profile.

Urban and Stormwater Flooding: Cathedral City’s urbanized environment features extensive impervious surfaces, including roads, parking lots, and commercial developments, which reduce natural water absorption and increase stormwater runoff. The city’s storm drain system is aging, minimal, and undersized in some areas, leading to localized flooding when rainfall exceeds the system’s capacity. Low-lying intersections and areas such as along Date Palm Drive, Ramon Road, Vista Chino, and Varner Road-are particularly vulnerable to temporary street flooding during heavy rain events.

Flash Flooding: Due to its desert climate and the presence of steep slopes in the Santa Rosa and San Jacinto Mountains, Cathedral City is vulnerable to flash flooding. Intense rainfall over a short duration can overwhelm natural drainage channels and stormwater infrastructure, leading to sudden and hazardous flood conditions. The Eagle Canyon and Cathedral Canyon drainages had historically funneled floodwaters and debris into developed areas. In the past 30 years the Riverside County Flood Control District (RCFCD) has completed the East and West Cathedral Canyon Flood Control Channels, respectively and in the past 6 years has completed the Eagle Canyon Dam Project, which collectively have reduced flooding due to flash flooding in the Cove neighborhood and along East Palm Canyon Drive.

Riverine Flooding: Although the Whitewater River is the primary drainage channel for the region, it can experience high flows during major storm events, potentially contributing to flood risks in Cathedral City. The river drains approximately 720 square miles and can generate storm flows of up to 47,000 cubic feet per second during a 100-year storm event.

Infrastructure-Related Flooding: Flooding in Cathedral City can also result from failures or limitations in stormwater management infrastructure. The city’s storm drain system, particularly in older developed areas, includes undersized pipelines that struggle to handle heavy runoff. Areas north of Interstate 10 and neighborhoods along major roadways have been identified as vulnerable to nuisance flooding due to outdated or insufficient drainage systems.

Local Hazard Mitigation Plan Update
87 Groundwater and Drainage Basin Flooding: Although Cathedral City is not prone to coastal or tidal flooding, rising groundwater levels and the limited capacity of stormwater retention basins can contribute to localized flood risks.

Location and Geographic Extent
Local Hazard Mitigation Plan Update
88 Local Hazard Mitigation Plan Update
89 Flooding in Cathedral City is not uniformly distributed across the city, as certain areas are more vulnerable due to elevation differences, drainage limitations, and surrounding land use. The city’s flood risk is influenced by its position within the Coachella Valley and its reliance on regional stormwater management systems, including the Whitewater River Channel and Cathedral Canyon Drainages.

Roadways and Intersections with Recurring Flooding Issues: Several roadways and intersections in Cathedral City experience frequent temporary flooding during heavy rain events, particularly in lowlying areas where storm drains have limited capacity or are blocked by debris. Major arterial roads with extensive paved surfaces, lack of stormwater undercrossing infrastructure, and limited adjacent natural absorption are particularly susceptible. Historically, areas near Vista Chino and Landau Boulevard, Vista Chino and Horizon Road, Date Palm Drive and Los Gatos Road, Dinah Shore Drive between Date Palm Drive and Cathedral Canyon, and Gerald Ford Drive at Plumley Road have been prone to floodrelated disruptions. These roads are critical to local and regional mobility, and temporary closures due to stormwater accumulation can create significant traffic delays. Additionally, the area bounded by McCallum Way, Avenida Maravilla, Landau Blvd and Vista Chino, as well as the region near Date Palm Drive, Ramon Road, Landau Blvd and Tortuga Road, have experienced periodic flooding events due to drainage constraints.

Industrial and Commercial Zones with High Runoff Volume: Cathedral City’s commercial and industrial areas contain extensive impervious surfaces, which prevent natural rainwater infiltration and contribute to increased stormwater runoff. Warehouses, shopping centers, and large paved parking lots exacerbate flooding risks, particularly in areas where older drainage infrastructure is insufficient to handle high-intensity rainfall. The Cathedral City Marketplace, along Date Palm Drive and Dinah Shore Drive , is one such location where stormwater ponding in parking areas has historically disrupted business operations and increased vehicle damage risks. Industrial zones along Ramon Road, Cathedral Canyon Drive, and Perez Road face additional risks, particularly in areas where large-scale runoff can overwhelm stormwater drainage capacity. In some cases, localized flooding may also pose risks of hazardous material exposure if floodwaters reach industrial sites with chemical storage.

Storm Drain Infrastructure and Flood Control Channels: Cathedral City relies on an extensive stormwater drainage network, including underground storm drains and open-channel flood control systems. The Whitewater River Channel is the primary flood control facility in the region, draining approximately 720 square miles and capable of handling 100-year storm flows of 47,000 cubic feet per second (cfs). The Cathedral Canyon Drainages, including the West and East Cathedral Canyon Channels, direct runoff from the Santa Rosa Mountains into the Whitewater River Stormwater Channel. These drainage corridors play a critical role in diverting stormwater away from developed areas but can become overwhelmed during extreme rainfall events.

Local Hazard Mitigation Plan Update
90 Storm drain outfalls near the Whitewater River and the Cathedral Canyon Drainages may experience temporary backups during heavy rainfall, leading to localized street flooding in adjacent neighborhoods. Improvements to these systems, including revetment and channel armoring projects, have been ongoing to mitigate erosion and reduce flood risks.

Retention basins in Cathedral City provide temporary storage for excess runoff, helping to prevent major flooding in urbanized areas. However, during extreme rainfall events, these basins may exceed their design capacity, leading to additional flood risks. The Eagle Canyon Dam, constructed in response to past damaging floods, plays a key role in stormwater detention and has significantly reduced flood impacts in western Cathedral City.

Relationship to Land Use and Development
Flood hazards in Cathedral City are closely tied to land use and development patterns, particularly in industrial, commercial, and residential corridors where high levels of impervious surfaces increase stormwater runoff. Future urban development, combined with projected climate change impacts, will further influence flood risks, necessitating improved land use planning and infrastructure adaptation.

Industrial and Commercial Development Impact on Flooding: Cathedral City's extensive commercial and industrial base has significantly altered natural drainage patterns, increasing reliance on engineered stormwater management solutions. Industrial growth in areas near Perez Road and East Palm Canyon Drive has led to the expansion of paved surfaces, contributing to increased stormwater runoff during heavy storms. Older industrial zones with outdated drainage infrastructure remain particularly vulnerable. Developments near Landau Boulevard and Ramon Road were built before modern stormwater retention requirements were implemented, leading to periodic flooding when storm drains reach capacity. Future redevelopment in these areas will need to incorporate updated stormwater management strategies, such as permeable pavement, bioswales, and retention basins, underground storage chambers to reduce flood risks.

Transportation Infrastructure and Flood Exposure: Cathedral City's major transportation corridors, including Interstate 10, East Palm Canyon Drive, and Date Palm Drive, are critical to regional mobility and commerce. Flooding on these routes can disrupt commuter traffic, emergency response operations, and freight movement, causing economic and logistical disruptions. Past flood events have led to temporary lane closures and delays along Dinah Shore Drive, Date Palm Drive, and Gerald Ford Drive, affecting access to businesses and residential areas. The I-10 corridor near between Palm Drive and Bob Hope Drive is a known flood-prone area, particularly during extreme storm events when runoff from nearby desert slopes converges into low-lying sections of the freeway. The closure of lanes along I-10 Local Hazard Mitigation Plan Update
91 withing this corridor occurred as recent as August of 2023, as a result of Tropical Storm Hilary water and mud flows.

Magnitude and Severity
Flood severity in Cathedral City is assessed using national hydrologic classification systems and local urban hydrology models. Factors such as flood depth, frequency, velocity, and the performance of stormwater infrastructure play a significant role in determining the impacts of flooding within the city.

FEMA Flood Zone Designations
FEMA’s Flood Insurance Rate Maps (FIRMs) categorize flood hazards based on probability and expected inundation levels:
• Zone X (Minimal Risk): The majority of Cathedral City falls into this category, indicating a low probability of large-scale flooding. However, localized stormwater flooding remains a persistent hazard, especially in areas with outdated or undersized drainage infrastructure. • Zone A (High-Risk 100-Year Floodplain): Areas near the Whitewater River and Cathedral Canyon Wash are mapped within this high-risk flood zone, particularly where historical flood events have occurred. FEMA requires properties in these zones to carry flood insurance if they have federally backed mortgages.

While large-scale riverine flooding is not a major concern for Cathedral City, urban flooding caused by storm drain capacity exceedance remains a significant issue during heavy precipitation events.

Local Flood Severity Analysis
Flood severity is further analyzed using urban hydrology models, which assess:
• Runoff Coefficients: Cathedral City's high proportion of impervious surfaces, including roadways and commercial developments, contributes to elevated runoff, increasing the risk of urban flooding during high-intensity storms.
• Stormwater System Capacity: The city’s storm drains and retention basins, particularly in older neighborhoods and industrial corridors, may not be sufficient to handle extreme storm events.

Infrastructure along major arteries, such as Date Palm Drive and Ramon Road, and Date Palm and Los Gatos Drive has been identified as vulnerable to capacity exceedance.

Local Hazard Mitigation Plan Update
92 • Flow Velocity and Debris Accumulation: Areas near the Whitewater River Channel and Cathedral Canyon Wash may experience high-velocity runoff, which can exacerbate erosion, cause structural damage, and transport debris into roadways.

Severity of Flooding
The magnitude of flooding in Cathedral City varies depending on storm intensity, drainage performance, and land use patterns:
• Minor Flooding occurs during moderate rainstorms when storm drains experience temporary blockages, leading to localized ponding in intersections and parking lots. These conditions typically resolve within hours.
• Moderate Flooding is less frequent but results from high-intensity rainstorms exceeding 1 inch per hour. This type of flooding temporarily overwhelms drainage systems, causing road closures on key transportation routes such as East Palm Canyon Drive and Date Palm Drive. Industrial and commercial properties in flood-prone areas may experience water infiltration, leading to operational disruptions and minor structural damage.
• Major Flooding is rare but can occur during extreme precipitation events, such as atmospheric river storms or back-to-back heavy rainfall systems. Such events could lead to significant infrastructure failures, particularly in areas reliant on aging stormwater infrastructure.

Floodwaters could inundate commercial and industrial zones, resulting in economic losses and potential contamination of stormwater with hazardous materials from nearby facilities.

Historical Occurrences
FEMA Disaster Declarations
Incident
Subcategory County
FEMA
Declaration
String
Calendar Year
of Declaration
Date
Month
Declaration
Date Declaration Title State
Flood Riverside
County DR-253-CA 1969 January 1/26/1969 SEVERE STORMS & FLOODING CA Flood Riverside
County DR-595-CA 1979 August 8/24/1979 SEVERE STORMS, FLOODING, AND MUDSLIDES CA Flood Riverside
County DR-979-CA 1993 February 2/3/1993

SEVERE WINTER STORM,

MUD & LAND SLIDES, &

FLOODING
CA
Flood Riverside
County DR-1046-CA 1995 March 3/12/1995

SEVERE WINTER STORMS,

FLOODING, LANDSLIDES,

MUD FLOW
CA
Local Hazard Mitigation Plan Update
93 Incident
Subcategory County
FEMA
Declaration
String
Calendar Year
of Declaration
Date
Month
Declaration
Date Declaration Title State
Flood Riverside
County DR-1203-CA 1998 February 2/9/1998 SEVERE WINTER STORMS AND FLOODING CA Flood Riverside
County DR-1577-CA 2005 February 2/4/2005

SEVERE STORMS, FLOODING,

DEBRIS FLOWS, AND

MUDSLIDES
CA
Flood Riverside
County DR-1585-CA 2005 April 4/14/2005

SEVERE STORMS, FLOODING,

LANDSLIDES, AND MUD AND

DEBRIS FLOWS
CA
Flood Riverside
County DR-1884-CA 2010 March 3/8/2010

SEVERE WINTER STORMS,

FLOODING, AND DEBRIS AND

MUD FLOWS
CA
Flood Riverside
County DR-4305-CA 2017 March 3/16/2017 SEVERE WINTER STORMS, FLOODING, AND MUDSLIDES CA Flood Riverside
County DR-4683-CA 2023 March 3/10/2023

SEVERE WINTER STORMS,

FLOODING, LANDSLIDES, AND

MUDSLIDES
CA
Flood Riverside
County DR-4777-CA 2024 February 2/18/2024

SEVERE STORMS AND
FLOODING (related to Hurricane
Hilary aftermath)
CA
Flood-related declared disasters in the vicinity of the Coachella Valley, 1953-2024. Source: FEMA California Governor-declared Declarations

DATE OF DISASTER TYPE OF DISASTER COUNTIES INVOLVED
None None (events causing flooding
mostly categorized under “Storms”)
None
List of Governor-declared disasters for property tax purposes since 1991. Source: California State Board of Equalization While Cathedral City is not classified as a high-risk flood zone under FEMA’s Flood Insurance Rate Maps (FIRMs), the city has been included in several federally declared disasters related to severe storms, flooding, and stormwater infrastructure impacts. These events have triggered access to federal recovery resources under the Stafford Act, supporting storm response, infrastructure repair, and resilience investments.
• FEMA DR-4305 (March 2017 – Severe Winter Storms, Flooding, and Mudslides): This disaster declaration covered widespread damages across Riverside County, including Cathedral City.

The city experienced roadway flooding, storm drain overflows, and localized infrastructure disruption during a sequence of severe winter storms.
• FEMA DR-4434 (February 2019 – Valentine’s Day Flood): Although Cathedral City was not named in the primary declaration, FEMA issued a federal disaster declaration for the Cahuilla Band of Indians following heavy rainfall and flash flooding on February 14, 2019, which Local Hazard Mitigation Plan Update
94 severely impacted Tribal lands within the region. These events highlight the broader Coachella Valley’s susceptibility to localized flood and mudflow hazards during high-intensity rainfall events, even in areas outside designated FEMA flood zones. • FEMA DR-4683 (January 2023 – Atmospheric River Storms): This declaration followed a sequence of powerful atmospheric river events that brought widespread flooding and

high winds to Southern California. In Cathedral City, impacts included localized road closures, temporary power outages, and strain on stormwater management infrastructure. • FEMA DR-4699 (March 2023 – Additional Atmospheric River Flooding): This follow-up declaration was issued after consecutive storm systems in March 2023 triggered further flooding, erosion, and drainage issues across Riverside County, including areas of Cathedral City. Transportation corridors and stormwater systems were again impacted, reinforcing the city’s vulnerability to extreme precipitation events under changing climate conditions.

Probability and Effects of Future Conditions
Overall probability over next five years: Unlikely.

Severe flooding events in Cathedral City are projected to increase in frequency and intensity due to climate change and continued urban development. Historical flood data, climate modeling, and stormwater infrastructure analysis indicate that short-duration, high-intensity rainfall events are becoming more frequent, potentially exceeding the capacity of existing drainage systems. Studies suggest that extreme precipitation events in California cities will continue intensifying, leading to heightened urban flooding risks.

Cathedral City experiences flood risks primarily from stormwater runoff and overflow from the Whitewater River and Cathedral Canyon drainage systems. The Whitewater River drains a vast watershed of approximately 720 square miles, and 100-year storm flows at Cathedral City are estimated at 47,000 cubic feet per second. Standard Project Flood (SPF) modeling suggests that in extreme cases, flow volumes could reach 85,000 cubic feet per second, with a recurrence interval of approximately 500 years.

Future Rainfall and Urban Flooding Risks: By 2050, climate models predict an increase in the intensity of atmospheric river storms, leading to longer periods of stormwater system overload and surface flooding. Storm drain exceedance models indicate that a 10-year return period storm could overwhelm existing drainage infrastructure in commercial and industrial areas, leading to prolonged flooding in key transportation corridors. Intersections with historical drainage challenges, such as Date Palm Drive and Ramon Road, as well as Dinah Shore Drive between Date Palm and Cathedral Canyon, are expected to experience increased stormwater accumulation.

Local Hazard Mitigation Plan Update
95 Pavement drainage analysis suggests that critical intersections and low-lying streets will likely see higher flood depths during extreme precipitation events, leading to road closures, vehicle stall-outs, and emergency response delays. By 2070, extreme precipitation events exceeding historical norms may become twice as frequent, increasing the probability of storm drain failures and localized ponding in both residential and industrial districts.

Development and Impervious Surface Impacts: Continued industrial and commercial development in Cathedral City will increase impervious surface coverage, reducing natural water absorption and increasing stormwater runoff. Currently, a significant portion of developed land in Cathedral City consists of impervious surfaces, including roadways, parking lots, and building footprints, contributing to elevated flood risks. Without enhanced stormwater management measures, future development may further exacerbate these challenges. New projects in high-risk flood areas will require mitigation strategies such as retention basins, bioswales, and permeable pavement systems to reduce runoff volume.

Storm Drain System Overload and Infrastructure Adaptation Needs: Existing storm drain infrastructure in Cathedral City is designed based on historical rainfall data, but climate change projections indicate that future storm events will more frequently exceed system capacity. Areas around McCallum Way, Avenida Maravilla, and Vista Chino have been identified as having higher stormwater accumulation risks. Additionally, storm drain outfalls near Whitewater River may experience temporary backups during heavy precipitation events, further increasing localized flooding risks.

By 2050, the probability of storm drain backups causing localized flooding is expected to increase significantly. Infrastructure adaptation measures, including expanded stormwater capacity, green infrastructure solutions, and increased maintenance of existing systems, will be necessary to mitigate future flood risks.

Projected Economic and Infrastructure Impacts: Economic damages from flooding in Cathedral City are expected to rise by 2050 due to the increasing frequency of storm events and continued urbanization. Roadway repair costs related to flood damage, particularly along major corridors like East Palm Canyon Drive and Date Palm Drive, could increase as recurring storm events degrade pavement conditions and drainage infrastructure. Flood-related business disruptions, particularly in commercial and industrial zones, may also lead to increased economic losses.

Local Hazard Mitigation Plan Update
96 Local Hazard Mitigation Plan Update
97 3.3.7 High wind/storms
Description
High wind events in Southern California stem from various meteorological phenomena, including Santa Ana winds, thunderstorm-related winds, and strong frontal systems. These events pose significant risks to infrastructure, utilities, and public safety.

Santa Ana Winds: Originating from high-pressure systems over the Great Basin, Santa Ana winds are dry, warm, and gusty northeast winds that blow from the interior of Southern California toward the coast and offshore. As these winds descend through mountain passes and canyons, they accelerate and warm, leading to extremely dry conditions. These winds are most common between September and April, with peak activity in the fall and early winter months. During strong events, wind speeds can reach sustained levels of 50 to 70 mph, with gusts exceeding 100 mph in certain locations. Santa Ana winds significantly increase wildfire risks by rapidly spreading flames through dry vegetation, leading to large-scale fire disasters and declared emergencies.

Thunderstorm and Downburst Winds: Thunderstorm-related winds result from rapid downdrafts, creating damaging straight-line winds. Downburst winds occur when storm clouds collapse, forcing a powerful surge of air toward the ground. These winds can reach speeds of 60 to 80 mph and are capable of uprooting trees, damaging power lines, and disrupting transportation networks. The force of these winds poses risks to aviation, utility infrastructure, and buildings, particularly those constructed before modern wind-resistant building codes were in place.

Gradient Winds from Storm Systems: Large-scale storm systems moving through Southern California generate strong gradient winds, particularly during winter storms. These winds develop when intense pressure differences drive sustained wind speeds of 40 to 60 mph, with higher gusts in areas with open terrain or near passes and canyons. Winter frontal storms associated with the Pacific jet stream often lead to long-duration high wind events, which can cause widespread utility outages, structural damage, and disruptions to transportation corridors.

In Cathedral City, high wind events have had tangible impacts on local events and infrastructure. For instance, in November 2024, dangerous weather conditions led to the cancellation of the final competition flight at the 10th Annual Cathedral City Hot Air Balloon Festival due to high winds, highlighting the challenges such conditions pose to outdoor activities and public gatherings.

Location and Geographic Extent
Local Hazard Mitigation Plan Update
98 Cathedral City is susceptible to high wind events, notably the Santa Ana winds. These winds originate from high-pressure systems over the Great Basin and flow towards the coast, accelerating through mountain passes such as the San Gorgonio Pass, which is in proximity to Cathedral City. As these winds descend, they warm and dry, leading to extremely low humidity levels. Santa Ana winds are most prevalent between September and April, with peak activity during the fall and early winter months. The National Weather Service notes that these winds can reach sustained speeds exceeding 40 mph, with gusts surpassing 60 mph during extreme events.

The topography of Cathedral City, characterized by its location within the Coachella Valley and near the San Gorgonio Pass, influences wind flow and intensity. The city’s open desert landscape allows winds to accelerate, particularly affecting areas with wide, open spaces such as industrial corridors and major transportation routes. These locations are especially vulnerable to wind-related hazards, including debris, downed power lines, and structural damage. The California State Hazard Mitigation Plan identifies utility disruptions, infrastructure damage, and wildfire ignition from wind-driven embers as primary risks associated with high wind events.

Relationship to Land Use and Development
In Cathedral City, land use and development patterns significantly influence the impact of high wind events:
• Industrial Areas: The city hosts numerous industrial and warehouse facilities, many featuring lightweight roofing materials and expansive structures prone to wind damage. These buildings can act as wind catchers, making them susceptible to roof failures, siding detachment, and accumulation of hazardous debris during strong wind events. Additionally, industrial zones often store hazardous materials, presenting further risks if containment systems are compromised.
• Transportation Corridors: Major highways and rail lines traverse Cathedral City, making transportation infrastructure vulnerable to wind-related disruptions. High-profile vehicles, such as trucks and trailers, are at risk of overturning during strong winds, leading to road closures and accidents. Debris, including fallen trees and damaged signage, can obstruct roadways, while rail operations may face disruptions due to overhead power line failures or debris on tracks.
• Residential Neighborhoods: Areas with mature trees and above-ground power lines are at increased risk of power outages and property damage. High winds can break large tree limbs, causing significant damage to homes and vehicles. Wind-driven debris, such as loose roofing Local Hazard Mitigation Plan Update
99 materials and outdoor furniture, can become projectiles, posing additional safety hazards. Older homes constructed before modern building code updates may lack adequate wind-resistant features, increasing their susceptibility to structural damage. • Critical Infrastructure: High winds pose substantial threats to power distribution systems, communication networks, and emergency response operations. Downed power lines can lead to extended outages, disrupting businesses and essential services. In extreme cases, power failures can hinder emergency response efforts by disabling traffic signals, communication towers, and public safety facilities. Utility companies may implement Public Safety Power Shutoffs during extreme wind events to reduce wildfire risk, but these measures also introduce challenges for residents and businesses reliant on uninterrupted power supply.

Magnitude and Severity
Understanding the magnitude and severity of high wind events in Cathedral City requires the use of standardized meteorological scales that quantify wind speeds, storm intensity, and associated damage potential. While hurricanes and tornadoes are rare, the region experiences significant risks from Santa Ana winds, winter storms, and atmospheric river events, all of which can impact infrastructure, transportation, and public safety.
https://www.icams-portal.gov/resources/ofcm/fmh/FMH1/fmh1_2019.pdf Local Hazard Mitigation Plan Update
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Beaufort Wind Force Scale: The Beaufort Wind Force Scale classifies wind speeds based on their observed effects on land and structures. In Cathedral City, the most relevant categories include:
• Beaufort Force 6-7 (25-38 mph): Strong winds that can displace unsecured objects, impact highprofile vehicles, and accelerate wildfire spread. • Beaufort Force 8-9 (39-54 mph): Gale-force winds capable of breaking tree limbs, causing minor structural damage, and resulting in power outages. • Beaufort Force 10-11 (55-73 mph): Storm-force winds that present significant risks to infrastructure, including damage to mobile homes and lightweight structures.

National Weather Service (NWS) High Wind Warning Criteria: The NWS issues alerts based on sustained wind speeds and gusts:
• Wind Advisory: Sustained winds of 31-39 mph or gusts of 46-57 mph for over an hour. • High Wind Warning: Sustained winds of 40+ mph or gusts exceeding 58 mph, with structural damage likely.

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• Extreme Wind Warning: Sustained winds over 115 mph, typically associated with extreme storm conditions.

The severity of high wind hazards depends on several factors, including wind speed, duration, and environmental conditions such as topography and urban development. is particularly vulnerable to three primary types of high wind events:

Santa Ana Winds: Santa Ana winds are warm, dry winds that develop from high-pressure systems over the Great Basin, accelerating as they move downslope into Southern California. These winds can persist for several days and create extreme fire conditions due to low humidity and high temperatures. • Typical sustained wind speeds range from 40-60 mph, with peak gusts exceeding 80 mph in extreme cases.
• Major impacts include wildfire spread, downed power lines, roadway hazards, and airborne debris, all of which increase emergency response demands. • Historical Santa Ana wind events have resulted in widespread infrastructure damage and FEMA-declared disasters due to fire ignition and rapid flame spread.

Thunderstorm Winds and Microbursts: Severe convective storms can generate strong winds, including microbursts and straight-line winds, which are particularly dangerous due to their sudden onset and localized nature.
• Wind speeds in microbursts can reach 60-100 mph, producing damage comparable to an EF0- EF1 tornado.
• Potential impacts include roof failures, structural collapses, and disruptions to aviation and transportation infrastructure.

Atmospheric River Events: Atmospheric rivers are long, narrow bands of concentrated moisture that bring heavy precipitation and strong winds to California, particularly during winter storm systems.

These events have become more intense due to climate change, leading to increased hazards from both wind and flooding.
• Wind speeds associated with atmospheric rivers typically range from 40-70 mph, especially along storm fronts.
• Secondary hazards include widespread flooding, road closures, and increased soil saturation, which can lead to landslides.

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Historical Occurrences
FEMA Disaster Declarations
Incident
Subcategory County
FEMA
Declaration
String
Calendar Year
of Declaration
Date
Month
Declaration
Date Declaration Title State
Severe Storm Riverside
County DR-253-CA 1969 January 1/26/1969 SEVERE STORMS & FLOODING CA Severe Storm Riverside
County DR-547-CA 1978 February 2/15/1978 COASTAL STORMS, MUDSLIDES & FLOODING CA Severe Storm Riverside
County DR-595-CA 1979 August 8/24/1979 SEVERE STORMS, FLOODING, AND MUDSLIDES CA Severe Storm Riverside
County DR-979-CA 1993 February 2/3/1993

SEVERE WINTER STORM,

MUD & LAND SLIDES, &

FLOODING
CA
Severe Storm Riverside
County DR-1046-CA 1995 March 3/12/1995

SEVERE WINTER STORMS,

FLOODING, LANDSLIDES,

MUD FLOW
CA
Severe Storm Riverside
County DR-1203-CA 1998 February 2/9/1998 SEVERE WINTER STORMS AND FLOODING CA Severe Storm Riverside
County DR-1577-CA 2005 February 2/4/2005

SEVERE STORMS, FLOODING,

DEBRIS FLOWS, AND

MUDSLIDES
CA
Severe Storm Riverside
County DR-1585-CA 2005 April 4/14/2005

SEVERE STORMS, FLOODING,

LANDSLIDES, AND MUD AND

DEBRIS FLOWS
CA
Severe Storm Riverside
County DR-1884-CA 2010 March 3/8/2010

SEVERE WINTER STORMS,

FLOODING, AND DEBRIS AND

MUD FLOWS
CA
Severe Storm Riverside
County DR-4305-CA 2017 March 3/16/2017 SEVERE WINTER STORMS, FLOODING, AND MUDSLIDES CA Severe Storm Riverside
County DR-4683-CA 2023 March 3/10/2023

SEVERE WINTER STORMS,

FLOODING, LANDSLIDES, AND

MUDSLIDES
CA
Severe Storm Riverside
County DR-4777-CA 2024 February 2/18/2024 SEVERE STORMS AND FLOODING CA Flood-related declared disasters in the vicinity of the Coachella Valley, 1953-2024. Source: FEMA

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California Governor-declared Declarations

DATE OF DISASTER TYPE OF DISASTER COUNTIES INVOLVED
Early February 2024,
beginning February 3
Severe winter storms Alameda, Butte, Glenn, Humboldt, Lake, Los Angeles, Marin, Mendocino, Monterey, Napa, Orange, Riverside, Sacramento, San Bernardino, San Diego, San Francisco, San Luis Obispo, Santa Barbara, Santa Clara, Santa Cruz, Solano, Sonoma, Sutter, Trinity, and Ventura
August 20, 2023 Hurricane Hilary Fresno, Imperial, Inyo, Kern, Los Angeles, Orange, Riverside, San Bernardino, San Diego, Siskiyou, Tulare, and Ventura
ebruary-March 2023 Severe winter storms Alameda, Alpine, Amador, Butte, Calaveras, Contra Costa, Del Norte, El Dorado, Fresno, Glenn, Humboldt, Imperial, Inyo, Kern, Kings, Lake, Los Angeles, Madera, Marin, Mariposa, Mendocino, Merced, Modoc, Mono, Monterey, Napa, Nevada, Orange, Placer, Plumas, Riverside, Sacramento, San Benito, San Bernardino, San Diego, San Francisco, San Joaquin, San Luis Obispo, San Mateo, Santa Barbara, Santa Clara, Santa Cruz, Shasta, Sierra, Solano, Sonoma, Stanislaus, Trinity, Tulare, Tuolumne, Ventura, Yolo, and Yuba
September 9, 2022 Tropical Storm Kay Imperial, Inyo, Los Angeles, Riverside, and San Bernardino January-February 2019 Winter storms Amador, Calaveras, El Dorado, Glenn, Humboldt, Lake, Los Angeles, Marin, Mendocino, Modoc, Mono, Monterey, Orange, Riverside, San Bernardino, San Diego, San Mateo, Santa Barbara, Santa Clara, Shasta, Sonoma, Tehama, Trinity, Ventura, Yolo January 2017 Storm System Alameda, Alpine, Amador, Butte, Calaveras, Contra Costa, Del Norte, El Dorado, Fresno, Humboldt, Inyo, Kern, Kings, Lake, Lassen, Los Angeles, Madera, Marin, Mendocino, Merced, Modoc, Mono, Monterey, Napa, Nevada, Orange, Placer, Plumas, Riverside, Sacramento, San Benito, San Bernardino, San Diego, San Francisco, San Luis Obispo, San Mateo, Santa Barbara, Santa Clara, Santa Cruz, Shasta, Sierra, Siskiyou, Solano, Sonoma, Stanislaus, Sutter, Tehama, Trinity, Tulare, Tuolumne, Ventura, Yolo, Yuba
July 18, 2015 Rainstorms Imperial, Kern, Los Angeles, Riverside, San Bernardino, San Diego December 2010 – January
2011
Winter storms Inyo, Kern, Kings, Los Angeles, Madera, Mariposa, Orange, Riverside, San Bernardino, San Diego, San Luis Obispo, Santa Barbara, Tulare
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DATE OF DISASTER TYPE OF DISASTER COUNTIES INVOLVED
January 17-21, 2010 Winter storms Calaveras, Imperial, Los Angeles, Orange, Riverside, San Bernardino, San Francisco, Siskiyou
March 2005 Severe rainstorms Kern, Los Angeles, Orange, Riverside, San Bernardino, San Diego, Santa Barbara, Ventura
January 2005 Storms Kern, Los Angeles, Orange, Riverside, San Bernardino, San Diego, Santa Barbara, Ventura
February 2, 1998 El Niño Alameda, Amador, Butte, Calaveras, Colusa, Contra Costa, Fresno, Glenn, Humboldt, Kern, Kings, Lake, Los Angeles, Marin, Mendocino, Merced, Monterey, Napa, Orange, Riverside,
Sacramento, San Benito, San Bernardino, San Diego, San Francisco, San Joaquin, San Luis Obispo, San Mateo, Santa Barbara, Santa Clara, Santa Cruz, Siskiyou, Solano, Sonoma, Stanislaus, Sutter, Tehama, Trinity, Tulare, Ventura, Yolo, Yuba
January 1995 Severe Winter Storms Alameda, Alpine, Amador, Butte, Colusa, Contra Costa, Del Norte, El Dorado, Fresno, Glenn, Humboldt, Kern, Kings, Lake, Lassen, Los Angeles, Madera, Marin, Mendocino, Modoc, Monterey, Napa, Nevada, Orange, Placer, Plumas, Riverside, Sacramento, San Bernardino, San Diego, San Luis Obispo, San Mateo, Santa Barbara, Santa Clara, Santa Cruz, Shasta, Siskiyou, Solano, Sonoma, Sutter, Tehama, Trinity, Ventura, Yolo, Yuba
December 1992 Late Winter Storms Alpine, Contra Costa, Fresno, Humboldt, Imperial, Lassen, Los Angeles, Madera, Mendocino, Modoc, Monterey, Napa, Orange, Plumas, Riverside, San Bernardino, San Diego, Santa Barbara, Sierra, Siskiyou, Sonoma, Tehama, Trinity, Tulare
List of Governor-declared disasters for property tax purposes since 1991. Source: California State Board of Equalization In December 2011, a significant windstorm affected Southern California, including Cathedral City. This event, driven by a strong pressure gradient over the Great Basin, resulted in sustained winds of 40-60 mph, with gusts exceeding 80 mph in certain areas. The storm caused widespread power outages, impacting over 400,000 residents, with some outages lasting multiple days. Emergency response teams addressed blocked roadways, damaged commercial signage, and structural failures. Although this event did not trigger a federal disaster declaration, it necessitated substantial state-level emergency response actions.

In February 2017, a powerful atmospheric river event brought damaging winds, heavy rainfall, and localized flooding to Cathedral City and surrounding communities. Wind speeds reached 50-65 mph, leading to tree falls, property damage, and power disruptions. This storm contributed to FEMA Disaster Declaration DR-4301-CA, which covered multiple counties in Southern California due to storm-related damages, including wind and flood impacts.

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In early January 2023, a series of winter storms driven by atmospheric rivers produced widespread damaging winds and intense rainfall across the region. Cathedral City experienced gusts exceeding 60 mph, resulting in damaged signage, utility failures, and transportation slowdowns. This event led to FEMA Disaster Declaration DR-4683-CA, issued due to the extensive damage across California. The incident underscored the increasing frequency of high-impact storm systems and the necessity for enhanced resilience planning.

In October 2020, a severe Santa Ana wind event impacted Cathedral City, characterized by high wind speeds, dry conditions, and elevated wildfire risks. Wind gusts exceeded 70 mph, causing power outages and hazardous driving conditions. The event coincided with extreme wildfire conditions, with embers from nearby fires traveling considerable distances, increasing ignition risks in urban areas. While no FEMA declaration was issued, local emergency response teams implemented high wind advisories, wildfire mitigation measures, and power shutoff protocols.

FEMA Disaster Declarations Related to High Winds and Storms • FEMA DR-4301-CA (February 2017): This disaster declaration followed a series of winter storms impacting multiple counties in California, including Riverside County. Cathedral City experienced wind-related damage to structures, utilities, and transportation networks. Federal funding supported public infrastructure repair, flood mitigation, and debris removal efforts. • FEMA DR-4683-CA (January 2023): Declared in response to severe winter storms and atmospheric river impacts across the state, this disaster declaration included Riverside County.

The city faced high wind gusts, localized flooding, and transportation disruptions. Federal assistance facilitated infrastructure repairs and bolstered emergency management efforts.

Probability and Effects of Future Conditions
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Overall probability over next five years: Likely.

While hurricanes and tornadoes remain low-probability hazards in Cathedral City, the region is susceptible to Santa Ana wind events, atmospheric river-driven storms, and convective windstorms.

Climate change is projected to influence the frequency and intensity of these events, thereby affecting their impact on the area.

Wind Speed Probability Models: Wind speed probability models integrate historical wind data, meteorological patterns, and climate projections to estimate the likelihood of high-wind events in Cathedral City. Agencies such as the National Weather Service (NWS), the Federal Emergency Management Agency (FEMA), and the California Governor's Office of Emergency Services (Cal OES) utilize these models to predict wind hazards and inform emergency planning. • Santa Ana Winds: Historically, Southern California experiences approximately 20 to 40 Santa Ana wind events annually, with peak gusts ranging from 40 to 80 mph. Climate projections indicate a potential reduction in the frequency of these events, particularly during the fall and spring seasons, while the intensity during peak months may remain relatively unchanged. • Severe Windstorms: The probability of storm-related winds exceeding 50 mph is estimated at once every 5 to 10 years, primarily resulting from Pacific storm systems. • Extreme Wind Events (60+ mph): Climate models suggest a 1 to 3% annual probability, typically associated with convective thunderstorms, downbursts, or frontal systems.

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Recurrence intervals, or return periods, estimate the likelihood of an event occurring over a given timeframe. Based on historical data from the NWS and FEMA:
• 40-50 mph winds: Expected every 1 to 2 years.
• 50-60 mph winds: Expected every 5 to 10 years.
• 60+ mph winds: Expected every 10 to 25 years.
• 80+ mph winds: Historically rare but possible in Santa Ana wind corridors or during extreme storm events.

Climate models from the National Oceanic and Atmospheric Administration's (NOAA) Geophysical Fluid Dynamics Laboratory (GFDL) and the California Climate Assessment indicate shifts in wind patterns due to atmospheric changes. Santa Ana wind events may decrease in overall frequency by 2050, especially during the fall and spring, but the intensity during peak months (December and January) is projected to remain relatively stable. t
Winter storm wind speeds are projected to rise by 5 to 10% due to enhanced storm intensities driven by warming Pacific waters and intensified atmospheric rivers. Convective windstorms, including microbursts and downbursts, are expected to become more common, with gusts exceeding 60 mph occurring 30 to 50% more frequently by 2050.

Future Projections for Hazard Severity and Frequency
• Santa Ana Winds: While the overall frequency of Santa Ana winds may decrease, particularly in the fall and spring, the intensity during peak months is expected to remain consistent. This stability in intensity could continue to exacerbate wildfire risks and air quality degradation during these periods. Urban expansion and climate change may increase wind-driven fire hazards, necessitating stricter vegetation management and infrastructure resilience planning. • Pacific Storm Systems: Atmospheric rivers and extratropical cyclones are anticipated to bring stronger winds, particularly during the winter storm season. Wind speeds exceeding 50 mph may become more frequent by 2050, increasing risks of power outages, transportation disruptions, and structural damage. Rain-loaded storm systems will add compounding hazards, including wind-driven tree falls, debris flows, and urban flooding. • Convective Windstorms: Short-duration, high-impact wind bursts, including microbursts and straight-line winds, are projected to increase due to shifting atmospheric instability patterns.

Severe wind gusts exceeding 60 mph from convective storms could occur 30 to 50% more frequently by 2050. Localized storm damage will increase, particularly in exposed areas with aging infrastructure.

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Structural stress on buildings, power lines, and transportation networks is expected to intensify due to higher wind speeds. Wildfire risks will rise as Santa Ana winds maintain their intensity during peak months. Emergency response challenges will also grow, requiring updated protocols for wind-related power outages, road closures, and infrastructure failures.

3.3.8 Cyberattack/IT disruption
Description
A cyberattack is a deliberate attempt to infiltrate, damage, or disrupt computer networks, digital infrastructure, or electronic systems. Cyber incidents can result from malicious activities, technical failures, or human error, compromising the confidentiality, integrity, and availability of critical data and services. Cyber threats pose risks to municipal government operations, emergency response services, utilities, transportation networks, and private sector businesses.

Types of Cyberattacks and IT Disruptions
Cyber threats take multiple forms, each with distinct impacts on essential services and infrastructure. • Ransomware attacks remain one of the most pervasive threats. In a ransomware incident, attackers use malware to encrypt data and systems, demanding payment for decryption. The 2019 Baltimore ransomware attack, for example, cost the city over $18 million and disrupted Local Hazard Mitigation Plan Update
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municipal services for weeks. If a similar attack occurred in Cathedral City, essential city services, police communications, and business operations could be severely impacted. • Distributed Denial-of-Service (DDoS) attacks flood online services and networks with excessive traffic, causing widespread service outages. In municipal systems, DDoS attacks could cripple online payment portals, emergency alert systems, and public communication platforms, impeding critical operations.
• Phishing and social engineering attacks exploit human vulnerabilities to steal credentials, financial information, and other sensitive data. Government agencies, businesses, and residents remain frequent targets of phishing schemes. In 2022 alone, phishing accounted for nearly 40% of all cyber breaches nationwide.
• Malware and spyware attacks involve malicious software that disrupts operations or steals sensitive data. These threats target public and private networks, increasing the risk of system failures and data breaches. A major cyber intrusion could compromise city databases, exposing confidential resident information.

Cyberattacks on critical infrastructure pose one of the most significant risks. Power grids, water treatment facilities, and transportation networks rely on automated control systems vulnerable to hacking. The 2021 Colonial Pipeline ransomware attack, which disrupted fuel supply across the East Coast, highlighted the vulnerabilities of essential services. A similar attack on Cathedral City’s infrastructure could result in widespread outages, water service disruptions, or traffic control failures.

Location and Geographic Extent
Cyber threats are not confined by geography but target digital infrastructure, networks, and interconnected systems essential to government operations, businesses, emergency services, and critical utilities. These cyber disruptions can originate from local, regional, or global sources, impacting systems that extend beyond municipal boundaries. Specific sectors and locations are particularly susceptible to cyber-related disruptions due to their reliance on information technology systems, data networks, and automated control mechanisms.

Municipal Government and Emergency Services: Cathedral City’s government offices, police and fire departments, emergency dispatch centers, and public safety systems depend heavily on secure IT networks and digital communications infrastructure. A cyberattack targeting these systems could disrupt 911 call centers, delaying emergency response coordination; compromise police and fire department databases, affecting investigations and resource deployment; or lock city employees out of municipal IT systems, hindering service delivery, financial operations, and public communication.

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Critical Infrastructure and Utility Networks: The city’s power grid, water treatment facilities, wastewater systems, and industrial utility services rely on Supervisory Control and Data Acquisition (SCADA) systems to monitor and regulate infrastructure operations. These SCADA systems provide real-time control of essential services such as electricity distribution, wastewater flow regulation, and potable water treatment processes. A cyberattack on SCADA infrastructure could severely disrupt operations. Such an event could result in the shutdown of power distribution or water supply systems, tampering with water quality settings that could lead to contamination, and disabling industrial controls essential to energy efficiency, air emissions monitoring, and equipment safety protocols. These threats are of increasing concern in hazard mitigation planning given the rise in both targeted attacks and system vulnerabilities in the public infrastructure sector. In August 2024, Halliburton, a global oilfield services provider, experienced a significant cyberattack that led the company to take its systems offline to protect internal data and infrastructure. Although not directly affecting Cathedral City, the incident highlights the growing national risk posed by cyber threats to critical infrastructure operators and industrial control systems, many of which share similar SCADA vulnerabilities.

During Tropical Storm Hilary in August 2023, several communities across the Coachella Valley experienced serious infrastructure disruptions. The storm caused flooding and high winds, and notably severed a fiber-optic line, leading to a regional 911 emergency communication outage. In Cathedral City, emergency services successfully rerouted 911 calls to the City’s non-emergency business lines, enabling continuity of emergency response while system repairs were underway. This incident illustrates both the vulnerability of communication infrastructure during compound weather events and the importance of local redundancy planning.

Industrial and Commercial Facilities: Cathedral City hosts numerous industrial facilities, warehouses, and distribution centers that depend on automated logistics systems, digital inventory management, and online supply chain coordination. A cyberattack on industrial networks could disrupt manufacturing and supply chain operations, causing financial losses and shipment delays; shut down automated equipment, leading to safety hazards and operational inefficiencies; and expose sensitive trade secrets and business data, affecting competitiveness and regulatory compliance.

Financial Institutions, Retail Businesses, and Healthcare Services: Banks, commercial businesses, and medical facilities rely on digital payment systems, financial networks, and electronic health records. A cyberattack could block access to financial transactions, preventing payroll processing, credit card payments, and ATM withdrawals; compromise confidential customer and patient data, leading to identity theft and regulatory violations; and cause business shutdowns or service disruptions, leading to economic losses and reduced public confidence. For instance, in May 2024, Ascension, a healthcare Local Hazard Mitigation Plan Update
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organization, experienced a ransomware attack that disrupted clinical functions and access to electronic health records, highlighting the potential impact of cyber incidents on healthcare services.

Relationship to Land Use and Development
While cybersecurity risks are not influenced by traditional land use patterns as natural hazards are, the expansion of digital infrastructure, smart city technologies, and industrial automation in Cathedral City has introduced new vulnerabilities that must be considered in urban planning and development.

Mention city’s update of the zoning code that is currently pre-internet.

Industrial Growth and Smart Infrastructure: Cathedral City’s industrial sector is increasingly adopting automated technologies, cloud computing, and Internet of Things (IoT) devices to enhance efficiency and productivity. While these advancements improve operations, they also increase exposure to cyber threats. The city’s Public Works Department offers programs such as the WaterSmart Landscape Grant Program and Smart Irrigation Controller Program, promoting the adoption of smart technologies in residential and commercial landscapes.

Municipal Services and Smart City Initiatives: The City of Cathedral City is incorporating smart technologies into public services, including traffic management, public utilities, and emergency response coordination. While these systems improve efficiency, they also create potential cyber vulnerabilities. The city’s Five-Year Strategic Plan emphasizes the integration of technology to enhance service delivery and operational efficiency, reflecting a commitment to smart city initiatives.

Commercial and Residential IT Vulnerabilities: With expanding broadband access, remote work infrastructure, and digital communication platforms, residents and businesses in Cathedral City face increased cyber risks from phishing scams, data breaches, and financial fraud. The city’s efforts to improve infrastructure aim to enhance connectivity and accessibility, which, while beneficial, also necessitate robust cybersecurity measures to protect the growing digital landscape.

Magnitude and Severity
To assess the severity of cyberattacks, standardized classification models focus on factors such as the scale of disruption, duration of system outages, data integrity compromise, financial impact, and potential threats to public safety.

Several government agencies and cybersecurity organizations have developed frameworks to categorize cyber incidents based on their impact and response level. Cathedral City can use these classification Local Hazard Mitigation Plan Update
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models to assess and respond to cybersecurity threats that could affect municipal operations, critical infrastructure, and private sector functions.

Cyber Incident Severity Schema (CISA/US-CERT): The Cybersecurity and Infrastructure Security Agency (CISA) and the United States Computer Emergency Readiness Team (US-CERT) use a fivelevel Cyber Incident Severity Schema to classify cyberattacks based on their impact on national security, public safety, and critical infrastructure:
• Emergency (Level 5): A catastrophic cyberattack causing nationwide or regional infrastructure failures, such as disabling power grids, financial networks, or emergency response systems.

Immediate federal response and emergency actions are required. • Severe (Level 4): A major Cathedral City causing widespread system outages, financial losses, or threats to public safety, such as ransomware shutting down a city’s government network or a cyberattack on water treatment facilities. Federal and state resources are activated. • High (Level 3): A significant cyberattack affecting one or more critical services, such as 911 dispatch, hospital networks, or major business operations, requiring multi-agency coordination to restore affected systems.
• Medium (Level 2): A targeted cyberattack or IT disruption affecting municipal departments, business systems, or industrial networks without immediate threats to public safety. • Low (Level 1): A minor cyber event such as phishing attempts, website defacement, or a localized malware infection with limited operational impact.

Cathedral City’s most severe potential cyber threats include ransomware attacks on city services, data breaches exposing sensitive resident information, and disruptions to power or water infrastructure via cyber intrusions into industrial control systems.

National Institute of Standards and Technology (NIST) Cyber Impact Scale: The National Institute of Standards and Technology (NIST) classifies cyber incidents based on their impact on confidentiality, integrity, and availability of information systems:
• Critical Impact: The attack completely disables essential public services, such as emergency dispatch, law enforcement systems, or critical utilities, leading to immediate risks to life and safety.
• High Impact: The attack compromises sensitive data, disrupts major government or business operations, or causes significant financial harm, requiring prolonged recovery efforts. • Moderate Impact: A cyberattack partially disrupts operations but does not fully compromise critical services, causing delays and operational inefficiencies.

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• Low Impact: The attack is minor and contained, such as a brief website outage or a phishing attempt detected before damage occurs.

Severity of Cyberattacks
Cyber threats vary in severity, ranging from low-impact phishing attempts to high-impact critical infrastructure disruptions. The most significant threats include:

Municipal and Emergency Services Disruptions: A ransomware attack or data breach targeting city government IT systems could disrupt financial transactions, permit processing, emergency services, and law enforcement databases. If 911 dispatch services, police records, or fire department communication networks were compromised, this could lead to delayed response times, compromised public safety, and legal liabilities for the city.

Critical Infrastructure Attacks: If cybercriminals or nation-state actors targeted Cathedral City’s power grid, water treatment facilities, or industrial SCADA (Supervisory Control and Data Acquisition) systems, the resulting outage or contamination event could create a public health emergency. An attack of this nature would require state and federal emergency response coordination to restore essential services.

Business and Industrial Cyber Disruptions: Industrial and logistics facilities often rely on automated control systems and cloud-based logistics operations. A cyberattack on an industrial network could shut down manufacturing production lines, disrupt supply chains, or expose proprietary business data.

This could result in millions of dollars in economic losses and potential job disruptions for local employees.

Widespread Personal Data Breaches: If a data breach exposed personally identifiable information (PII) from municipal databases, financial institutions, or healthcare providers, it could lead to identity theft, financial fraud, and regulatory penalties. A large-scale breach affecting thousands of residents or businesses could result in long-term legal and reputational consequences for the city and affected organizations.

Transportation and Traffic Management System Disruptions: An attack on Cathedral City’s traffic control systems, transit networks, or freeway communication systems could create major congestion, increase accident risks, and disrupt freight movement through the city. A cyberattack affecting highway sensors, traffic signals, or public transit payment systems would require urgent mitigation efforts to prevent secondary transportation hazards
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Historical Occurrences
FEMA Disaster Declarations
Incident
Subcategory County FEMA Declaration String
Calendar Year of
Declaration
Date
Month
Declaration
Date
Declaration
Title State
None None None None None None None None
California Governor-declared Declarations

DATE OF DISASTER TYPE OF DISASTER COUNTIES INVOLVED
None None None
List of Governor-declared disasters for property tax purposes since 1991. Source: California State Board of Equalization Although Cathedral City has not been directly targeted, past cyber incidents in California and across the United States illustrate the types of cyber threats that could impact the city. 2018 City of Atlanta Ransomware Attack: In March 2018, a ransomware attack crippled the City of Atlanta’s IT infrastructure, locking city employees out of email accounts, financial processing systems, and public service databases.
• The attackers demanded approximately $51,000 in Bitcoin, but the total cost of recovery exceeded $17 million due to system restoration, data recovery, and security enhancements. • 911 dispatch systems, municipal court records, and online payment systems were rendered inoperable for weeks.
• This attack demonstrated how a single cyber incident can disrupt government functions and require extensive emergency response measures.
2019 Los Angeles County Phishing Attack: In 2019, Los Angeles County experienced a large-scale phishing attack that compromised email accounts of county employees, including those in the Department of Public Works, Sheriff’s Department, and health services. • More than 1,000 employees were affected, with attackers gaining access to sensitive county records and resident information.
• The breach exposed social security numbers, financial records, and personal medical data, creating risks of identity theft and fraud.

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2021 Colonial Pipeline Cyberattack: In May 2021, the Colonial Pipeline, which supplies nearly 50% of the East Coast’s fuel, was shut down due to a ransomware attack carried out by criminal hacking group DarkSide.
• The attack disrupted fuel distribution for several days, causing shortages and price spikes across multiple states.
• The attackers gained access through a compromised VPN password, highlighting vulnerabilities in remote access systems used by industrial control networks. 2022 Los Angeles Unified School District Ransomware Attack: In September 2022, the Los Angeles Unified School District (LAUSD) suffered a major ransomware attack that encrypted data across its entire school network, affecting over 600,000 students. • Class schedules, student records, and payroll systems were disrupted, forcing emergency IT restoration efforts.
• The attack targeted a weak point in LAUSD’s cybersecurity protocols, emphasizing the need for multi-layered protection and regular system updates, 2023 U.S. Healthcare Cyberattacks: Healthcare providers, including hospitals and emergency medical networks in California, have been targeted by ransomware groups, causing disruptions to patient care, medical records access, and emergency response coordination. • In February 2023, a cyberattack on a hospital system in Southern California delayed emergency room services and patient admissions.
• In August 2023, a ransomware attack on a major health insurance provider disrupted payment processing and patient scheduling for multiple medical facilities.

FEMA Disaster Declarations Related to Cyberattacks
While cyberattacks do not traditionally trigger standalone FEMA disaster declarations, they are increasingly being incorporated into federal emergency response planning. FEMA recognizes cyber incidents as potential components of broader disaster scenarios, such as coordinated attacks on power grids, financial institutions, or emergency communication networks. • FEMA DR-4569-CA (October 2020 – Wildfires and Public Safety Power Shutoffs): Although this disaster declaration was issued due to wildfires in California, it included

cybersecurity concerns related to the Public Safety Power Shutoff (PSPS) system, which could be targeted by cybercriminals to create artificial outages.

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• Presidential Policy Directive 21 (PPD-21) – Critical Infrastructure Cyber Resilience: This directive, issued in 2013 and expanded in 2021, identifies 16 critical infrastructure sectors, including energy, water, transportation, and communications, that require federal cybersecurity protection.

Probability and Effects of Future Conditions
Overall probability over next five years: Likely.

Cyber threats are a rapidly evolving hazard that poses a significant risk to municipal governments, critical infrastructure, businesses, and residents. As Cathedral City continues to expand its digital infrastructure, adopting smart city technologies, and increasing its reliance on cloud-based services, the city’s vulnerability to cyberattacks is expected to rise. The sophistication of cyber threats, combined with the interconnectivity of IT systems across essential services, presents an escalating challenge.

Future risks will be further compounded by the intersection of climate-driven disruptions, geopolitical instability, and the continued advancement of cyberattack techniques.

Reports from the Cybersecurity and Infrastructure Security Agency (CISA) and the Federal Bureau of Investigation (FBI) highlight that ransomware, phishing, and denial-of-service (DoS) attacks have been responsible for disrupting city services, financial systems, and emergency response capabilities at an accelerating pace. Between 2018 and 2023, ransomware incidents against U.S. municipalities doubled, largely due to cybercriminals exploiting vulnerabilities in remote-access software, cloud-based storage, and legacy municipal IT systems. Additionally, the rise of industrial cyberattacks has placed critical infrastructure at heightened risk, particularly as utilities and government services transition toward automation and greater digital integration.

Given these trends and the growing attack surface created by digital modernization, Cathedral City is at a high probability of experiencing a cyberattack affecting municipal operations, emergency services, and critical infrastructure systems.

The frequency and severity of cyberattacks are projected to increase due to several emerging trends.

The expansion of artificial intelligence (AI) in cybercrime will allow threat actors to automate attacks, improve malware evasion techniques, and escalate the volume of cyber intrusions. AI-driven ransomware and social engineering campaigns are expected to become more sophisticated, making detection and prevention more challenging for local governments. At the same time, threats to industrial control systems (ICS) will continue to rise, particularly within water and power utilities that rely on Supervisory Control and Data Acquisition (SCADA) systems. These systems, which are essential for infrastructure automation, present attractive targets for cybercriminals seeking to disrupt essential services.

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The rapid expansion of smart city technologies further increases cyber vulnerabilities. Internet of Things (IoT) devices, used for traffic management, emergency response coordination, and municipal surveillance, create additional entry points for attackers. As interconnected urban infrastructure becomes more commonplace, cyber risks will extend beyond traditional IT networks, directly affecting public safety and urban operations. If a cyberattack were to disable Cathedral City’s IT networks, cascading failures could disrupt power distribution, water treatment systems, and emergency communication channels. The potential for such disruptions reinforces the need for heightened cyber resilience across municipal agencies.

Cyberattacks pose significant financial risks to municipalities, with the cost of ransomware attacks on mid-sized cities averaging over $3.5 million per incident. These costs encompass system restoration, legal expenses, data recovery, and operational downtime. In addition to direct recovery expenses, local governments are facing a sharp rise in cybersecurity insurance premiums, with municipal cyber liability policies increasing by 300% since 2020. The economic implications of prolonged IT disruptions extend beyond city hall, affecting residents and businesses that rely on municipal services. A single cyberattack on a city’s financial system can result in revenue losses ranging from $5 million to $25 million, depending on the extent of downtime, data loss, and service disruption. These escalating costs highlight the urgent need for robust cybersecurity investments to mitigate financial and operational risks.

The intersection of climate change and cybersecurity presents additional challenges for municipal resilience planning. Natural disasters such as wildfires, extreme heat events, and severe storms have been increasingly exploited by cybercriminals, who time attacks to coincide with emergency situations when response capabilities are already strained. The growing reliance on digital emergency management tools, including cloud-based crisis coordination platforms, introduces further vulnerabilities that must be addressed.

Energy grid vulnerabilities also represent a growing concern, as increasing temperatures and extreme weather conditions lead to surging electricity demand. With power distribution networks becoming more digitized, cyber threats targeting grid infrastructure could result in prolonged blackouts during critical periods. In a worst-case scenario, a cyberattack on a power utility during a climate-driven emergency could significantly delay response efforts, exacerbating the overall impact on public health and safety.

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3.3.9 Infectious disease/pandemic
Description
Infectious diseases and pandemics pose significant risks to public health, economic stability, and societal function. These hazards can spread rapidly, overwhelm healthcare systems, and disrupt essential services. An infectious disease outbreak occurs when a pathogen-such as a virus, bacterium, or fungus-spreads within a community, region, or globally, potentially leading to widespread illness and fatalities.

A pandemic is a large-scale infectious disease outbreak that extends across multiple countries or continents, affecting a significant portion of the global population. Pandemics often arise from novel or highly transmissible pathogens with little to no preexisting immunity, such as influenza viruses, coronaviruses (e.g., SARS-CoV-2), or emerging zoonotic diseases. The World Health Organization (WHO) and the Centers for Disease Control and Prevention (CDC) define pandemics as global epidemics requiring coordinated international response efforts.

The spread and severity of an infectious disease outbreak depend on its mode of transmission, human behavior, and the effectiveness of public health interventions.

Modes of Transmission: Understanding how a disease spreads is critical for developing mitigation strategies:
• Airborne Transmission – Pathogens spread through respiratory droplets or aerosolized particles (e.g., COVID-19, tuberculosis, measles).
• Direct Contact Transmission – Infection occurs through physical contact with an infected person, contaminated surfaces, or bodily fluids (e.g., Ebola, norovirus, MRSA). • Vector-Borne Transmission – Carriers such as mosquitoes and ticks spread disease (e.g., West Nile virus, Zika virus, Lyme disease).
• Foodborne and Waterborne Transmission – Contaminated food or water supplies contribute to outbreaks (e.g., Salmonella, cholera).

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The interaction of these transmission pathways with climate change and urban development increases the complexity of predicting and mitigating infectious disease risks.

Characteristics of Pandemic-Capable Diseases: Not all infectious diseases result in pandemics.

Pathogens with pandemic potential typically share the following characteristics:
• High transmissibility – The ability to spread efficiently from person to person, often before symptoms appear (e.g., influenza, COVID-19).
• Global impact potential – The capacity to move beyond a single region and affect multiple countries (e.g., H1N1, SARS).
• Limited preexisting immunity – A lack of natural or vaccine-induced immunity within the population, increasing infection susceptibility (e.g., novel coronaviruses, emerging zoonotic diseases).
• Severe healthcare strain – A high rate of infections overwhelming hospitals, leading to resource shortages and increased mortality.

Location and Geographic Extent
Infectious diseases and pandemics differ from natural hazards in that they do not adhere to physical geographic boundaries. Instead, their spread is influenced by human mobility, population density, infrastructure resilience, and the effectiveness of containment measures. The geographic extent of an outbreak can range from localized clusters to global pandemics, with transmission pathways dictated by factors such as travel patterns, workplace interactions, and healthcare access.

Cathedral City does not possess unique geographic attributes that inherently increase the likelihood of infectious disease outbreaks. However, as a city with a diverse economy encompassing industrial, commercial, and service sectors, its connectivity to major transportation corridors and reliance on a commuter labor force elevate the potential for disease spread. The city’s economic and social integration with the broader Riverside County region necessitates a preparedness framework that accounts for emerging infectious disease threats and pandemic response capabilities.

Several factors may influence the likelihood and severity of disease transmission in specific areas:

Industrial and Commercial Zones: Cathedral City’s economy includes manufacturing, logistics, and industrial operations, which often require employees to work in enclosed spaces for prolonged periods.

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physical interactions. During the COVID-19 pandemic, outbreaks in similar settings nationwide underscored the need for enhanced workplace health and safety protocols, including ventilation improvements and flexible sick leave policies.

High-Traffic Transportation Corridors: Cathedral City’s location along major transportation routes, including Interstate 10 and U.S. Route 111, facilitates high-volume movement of goods and people.

The presence of freight rail lines further integrates the city into regional and national supply chains.

These transportation networks can accelerate the spread of infectious diseases by facilitating close contact among travelers, workers, and freight operators. Public transit users, particularly those relying on buses and ride-sharing services, are also at heightened exposure risk, especially during peak travel hours.

Healthcare Facilities and Long-Term Care Centers: Cathedral City is home to healthcare facilities, assisted living centers, and skilled nursing homes that serve elderly residents and individuals with chronic health conditions. These populations face heightened risks from infectious diseases due to weakened immune systems and frequent medical interactions. Historical data from past pandemics, including COVID-19 and influenza outbreaks, demonstrate that long-term care facilities are particularly susceptible to rapid disease spread. Effective infection control measures, such as vaccination programs, personal protective equipment (PPE) distribution, and emergency staffing plans, are essential for mitigating risks in these environments.

Schools and Childcare Facilities: Educational institutions, including schools, daycare centers, and afterschool programs, serve as focal points for community interaction and can amplify disease transmission.

Children, particularly those in elementary schools, are more susceptible to contracting and spreading infectious diseases such as influenza, measles, and gastrointestinal viruses due to frequent close contact and underdeveloped immune responses. High absenteeism rates during pandemics can disrupt education and burden working families, while school closures-as seen during the COVID-19 pandemiccan have cascading socioeconomic effects.

Public Gathering Spaces and Retail Centers: Cathedral City contains numerous retail establishments, dining venues, fitness centers, and entertainment spaces that serve as community hubs. Crowded environments, especially during peak hours and special events, increase the likelihood of airborne and surface-contact disease transmission. Large-scale public events, religious services, and recreational activities also present potential exposure risks.

Magnitude and Severity
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Infectious disease outbreaks and pandemics pose significant risks to public health, the economy, and societal stability. The severity of an outbreak is determined by multiple factors, including the pathogen's transmissibility, morbidity and mortality rates, impact on healthcare systems, and economic disruption. Unlike natural hazards with standardized intensity scales, infectious disease severity is assessed using epidemiological and clinical metrics, such as the basic reproduction number (R₀), case fatality rate (CFR), and excess mortality.

Pandemic classification and response levels are guided by international and national health agencies, including the World Health Organization (WHO), the Centers for Disease Control and Prevention (CDC), and state and local public health departments. The impact of a pandemic also depends on the availability and effectiveness of medical countermeasures, including vaccines, antiviral treatments, and healthcare surge capacity. Pandemic severity is evaluated using epidemiological models, hospital capacity assessments, and economic impact studies. The following frameworks provide a structured approach to measuring and understanding pandemic severity:
• Basic Reproduction Number (R₀): The Basic Reproduction Number (R₀) is a fundamental metric indicating the average number of secondary infections caused by a single infected individual in a fully susceptible population. Higher R₀ values correlate with greater transmission potential, necessitating stronger mitigation measures such as vaccination, social distancing, and quarantine protocols.
• R₀ < 1 – The disease is expected to decline over time. • R₀ = 1 – The disease maintains a steady presence without significant outbreaks. • R₀ > 1 – The disease spreads exponentially, increasing the risk of a pandemic.

Past pandemics have exhibited different R₀ values, influencing their severity and response measures:
• Seasonal Influenza: R₀ ≈ 1.3
• COVID-19 (original strain): R₀ ≈ 2.5
• Measles: R₀ ≈ 12–18 (one of the most highly contagious diseases known) • Case Fatality Rate (CFR): CFR measures the proportion of deaths among confirmed cases and is a key indicator of pandemic severity. Higher CFR values indicate greater strain on public health infrastructure and higher mortality risk:
• Low-Severity Disease (CFR < 0.1%) – Includes common seasonal influenza strains. • Moderate-Severity Disease (CFR 0.1% – 5%) – Includes pandemic influenza (H1N1) and certain COVID-19 strains.

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• High-Severity Disease (CFR > 10%) – Includes Ebola (CFR ~50%), SARS (CFR ~11%), and MERS (CFR ~34%).
• Hospitalization and Healthcare System Strain: A pandemic’s severity is also measured by the burden it places on healthcare systems. High hospitalization rates can overwhelm medical facilities, necessitating emergency expansion measures and surge staffing. Metrics include:
• Hospitalization Rate – Percentage of infected individuals requiring hospital care. • ICU Admission Rate – Proportion of hospitalized patients requiring intensive medical intervention.
• Bed Occupancy Rate – Percentage of available hospital beds occupied by pandemic patients.

• Pandemic Severity Assessment Framework (PSAF): The CDC’s Pandemic Severity Assessment Framework (PSAF) categorizes pandemics based on transmissibility and clinical severity:
• Category 1 (Mild Pandemic): CFR < 0.1% (e.g., seasonal flu). • Category 2–3 (Moderate Pandemic): CFR between 0.1% and 1.0% (e.g., 2009 H1N1 pandemic).
• Category 4–5 (Severe Pandemic): CFR > 1.0% (e.g., 1918 Influenza Pandemic, early COVID-19 waves).

Severity of Potential Infectious Disease Outbreaks
The impact of an infectious disease outbreak in Cathedral City would depend on multiple factors, including public health response capacity, local healthcare infrastructure, and workforce resilience.

Cathedral City, located in the Coachella Valley, has a diverse economy with significant employment in sectors such as retail, food services, and personal care. During the COVID-19 pandemic, the Coachella Valley experienced substantial job losses, with projections indicating a decline of 28.7% in employment from December 2019 to May 2020. Sectors like sales, food preparation, and personal care were among the most affected, leading to high absenteeism and supply chain disruptions. This underscores the need for enhanced workplace safety policies, including personal protective equipment (PPE), remote work accommodations, and staggered shifts.

The Coachella Valley’s healthcare infrastructure comprises three general acute care hospitals:

Eisenhower Health, Desert Regional Medical Center, and John F. Kennedy Memorial Hospital, collectively offering 1,006 licensed beds. However, 86% of these beds are located in the western part of the valley, potentially limiting access for residents in other areas. During high-severity pandemics, this distribution may lead to ICU bed shortages, increased emergency department congestion, and supply chain challenges for critical medical equipment, including ventilators and PPE.

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Certain populations within Cathedral City face heightened risks due to age, preexisting health conditions, or economic status. The Coachella Valley has communities with significant disparities between rich and poor, with poverty heavily concentrated in geographically isolated areas. These communities often exhibit lower rates of medical coverage, and residents may face barriers to healthcare access, increasing disease spread. Additionally, long-term care and assisted living facilities require stringent infection control measures to protect vulnerable individuals.

Historical Occurrences
FEMA Disaster Declarations
Incident
Subcategory County FEMA Declaration String
Calendar Year of
Declaration
Date
Month
Declaration
Date Declaration Title State
Biological Riverside
County DR-4482-CA 2020 March 3/22/2020 COVID-19 PANDEMIC CA Flood-related declared disasters in the vicinity of the Coachella Valley, 1953-2024. Source: FEMA California Governor-declared Declarations

DATE OF DISASTER TYPE OF DISASTER COUNTIES INVOLVED
March 2020 COVID-19 All 58 counties (including Riverside County) List of Governor-declared disasters for property tax purposes since 1991. Source: California State Board of Equalization Throughout history, infectious disease outbreaks and pandemics have profoundly impacted public health, economies, and societies. While Cathedral City has not been the epicenter of a pandemic, it has been affected by regional, national, and global infectious disease events. These outbreaks have shaped public health policies, emergency response planning, and business continuity strategies in the area.

The 1918 Influenza Pandemic, commonly known as the "Spanish Flu," was one of the deadliest global disease outbreaks, infecting approximately one-third of the world’s population and causing an estimated 50 million deaths worldwide. During this period, Riverside County, where Cathedral City is located, experienced significant morbidity and mortality. Local governments implemented quarantine measures, business closures, and mask mandates to curb the spread of the virus. The pandemic's impact on the local workforce, including agricultural and service industries, led to economic disruptions and highlighted the need for improved public health infrastructure.

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The 1957–1958 Influenza Pandemic, known as the "Asian Flu," resulted in an estimated 1–2 million deaths worldwide and caused severe economic disruptions due to workforce absenteeism. California's healthcare system was heavily burdened, prompting public health authorities to implement vaccination programs. Communities in Riverside County, including Cathedral City, experienced increased healthcare demands and workforce shortages, underscoring the importance of vaccination and public health preparedness.

The 2009 H1N1 Influenza Pandemic, referred to as the "Swine Flu," caused an estimated 274,000 hospitalizations and 12,500 deaths in the United States. Riverside County reported numerous confirmed cases, leading to school closures, vaccination campaigns, and emergency health declarations. The Federal Emergency Management Agency (FEMA) provided funding to local governments for pandemic response, including testing, treatment, and public education efforts. In Cathedral City, schools and businesses faced operational disruptions due to workforce absences and public health restrictions, emphasizing the need for effective communication and continuity planning.

During the 2014–2016 West Africa Ebola Outbreak, while the Ebola virus did not spread widely in the United States, Riverside County health officials implemented emergency response protocols due to the risk of imported cases. Local hospitals and emergency services conducted Ebola preparedness drills and enhanced biosecurity protocols. Emergency medical and public health personnel in Cathedral City participated in regional coordination efforts to enhance infectious disease containment procedures, reflecting the city’s commitment to global health security.

The 2019–2023 COVID-19 Pandemic was the most significant infectious disease event affecting Cathedral City in modern history. Riverside County experienced over 5,000 fatalities, with Cathedral City reporting a substantial number of cases. Business closures, workforce disruptions, and supply chain delays affected various sectors, including tourism, retail, and healthcare. School closures and transitions to remote learning impacted students, educators, and working parents. Mass vaccination campaigns were launched across Riverside County, including sites in Cathedral City, to ensure vaccine accessibility for residents and essential workers. The pandemic highlighted the city’s resilience and the critical role of community cooperation in public health initiatives.

In 2022, Riverside County declared a public health emergency in response to the global monkeypox (Mpox) outbreak. The outbreak was contained through targeted vaccination efforts and public health education campaigns. Cathedral City collaborated with county health officials to provide resources and information to residents, demonstrating the importance of proactive public health measures in managing emerging infectious diseases.

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FEMA issues disaster declarations for pandemics when they cause widespread infrastructure strain, economic damage, or require large-scale federal assistance. Cathedral City has benefited from federal emergency support during national and statewide pandemic responses.

During the COVID-19 Pandemic (FEMA DR-4482, March 2020 – Ongoing), federal assistance provided funding for emergency medical response, personal protective equipment (PPE) distribution, and economic relief programs in California. Riverside County, including Cathedral City, received support for vaccination sites, hospital resources, and small business assistance. This remains one of the most extensive public health emergency responses in FEMA history, underscoring the collaborative efforts between federal, state, and local agencies in addressing public health crises.

During the 2009–2010 H1N1 Influenza Pandemic, federal assistance helped provide flu vaccines, public health messaging, and antiviral medication stockpiles for state and local governments. Healthcare providers in Cathedral City benefited from county-level allocations of medical resources, highlighting the importance of federal support in enhancing local public health capacities during infectious disease outbreaks.

Probability and Effects of Future Conditions
Overall probability over next five years: Unlikely.

Public health agencies, including the Centers for Disease Control and Prevention (CDC), the World Health Organization (WHO), and the Riverside County Department of Public Health, utilize predictive modeling to assess disease transmission patterns and outbreak probabilities. These models integrate factors such as pathogen characteristics, environmental influences, and human movement patterns to estimate the likelihood of future pandemics and emerging infectious diseases.

The WHO and CDC have identified an increasing emergence of novel infectious diseases, with approximately 75% being zoonotic-transmitted from animals to humans. The probability of another pandemic occurring within the next few decades is considered high, with respiratory viruses, such as influenza and coronaviruses, being the most probable causative agents. Additionally, climate change is altering disease transmission patterns by expanding the reach of vector-borne illnesses like West Nile virus into regions such as Southern California. Cathedral City must incorporate these projections into emergency response planning, addressing both airborne diseases and the growing threat of vectorborne diseases driven by rising temperatures.

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different population groups. In communities like Cathedral City, several key factors influence transmission dynamics. Workplace transmission risks are significant in sectors where employees work in enclosed spaces with shared equipment, increasing the potential for disease spread. The city’s proximity to major transportation corridors connects Cathedral City to higher-density urban centers, which could accelerate disease transmission during an outbreak. Population movement patterns, including gatherings in schools, long-term care facilities, and retail centers, also play a role in determining the likelihood and severity of an outbreak.

The impact of a future pandemic will also depend on the strain placed on the healthcare system and the capacity for medical response. During the COVID-19 pandemic, hospitals in Riverside County, serving Cathedral City, experienced severe strain, with ICU occupancy rates exceeding 90% during peak periods. Future pandemics with high hospitalization rates could similarly overwhelm emergency medical services and necessitate the expansion of surge capacity at regional hospitals.

Although the exact timing of future pandemics cannot be predicted, global epidemiological trends indicate that severe infectious disease outbreaks are likely to occur more frequently due to increased international travel, environmental changes, and microbial evolution. Historical patterns suggest that large-scale pandemics have occurred approximately every 30 to 50 years, but modern factors, such as increased human-animal interactions and climate change, may accelerate this timeline. The CDC and WHO have identified multiple viral families, including coronaviruses, influenza viruses, and paramyxoviruses, with pandemic potential. Riverside County’s role as a transportation hub increases the likelihood of early exposure to emerging diseases, which could affect Cathedral City before containment measures are widely implemented. In response, Cathedral City must maintain an adaptive public health framework that allows for rapid adjustments to emerging disease threats and changing transmission patterns.

Future pandemics could vary widely in severity. Some may cause widespread illness with low mortality rates, similar to the 2009 H1N1 influenza pandemic, while others could result in high fatality rates and healthcare system breakdowns, resembling the early waves of COVID-19 or historical outbreaks such as the 1918 influenza pandemic. Models suggest that a pandemic with a case fatality rate (CFR) between 1% and 3% could lead to significant social and economic disruptions, while a CFR exceeding 5% could trigger global instability. Additional concerns, such as antibiotic resistance and novel pathogen evolution, could further increase the severity of future outbreaks and complicate containment efforts.

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Climate change is expected to play a growing role in the emergence and spread of infectious diseases.

Rising temperatures and shifting precipitation patterns are expanding the range of vector-borne diseases, such as West Nile virus, into new geographic areas. Urban heat islands, including areas in Cathedral City, may create microenvironments conducive to increased mosquito breeding and disease transmission. Additionally, worsening air pollution and wildfire smoke-both becoming more frequent in California-can exacerbate respiratory infections and make populations more vulnerable to airborne diseases.

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3.3.10 Landslides
Description
Landslides are the downslope movement of rock, soil, or debris due to gravity, often triggered by factors such as seismic activity, heavy rainfall, or human-induced alterations to the landscape. In Cathedral City, landslide hazards are primarily associated with seismically induced slope instability, rockfalls, and debris flows, particularly in areas of steep terrain such as the Santa Rosa Mountains and the Indio Hills.

Landslides present a significant hazard to transportation infrastructure, buildings, and utilities, particularly where development has expanded into areas of high susceptibility. The effects of landslides can be exacerbated by earthquakes, heavy precipitation, and wildfires, which reduce soil cohesion and increase runoff.

Local Susceptibility and Risk Factors: Cathedral City is situated in a geologically active region, with fault lines capable of generating strong ground shaking. Seismically induced slope instability is a particular concern in the steep slopes of the Santa Rosa Mountains and the Indio Hills, where fractured bedrock and loose sediments make these areas prone to landslides. The 2040 Cathedral City General Plan identifies a moderate to high potential for seismically induced rockfalls and landslides, particularly where steep slopes exist adjacent to developed areas.

The East and West Cathedral Canyon Washes provide some level of protection against slope instability by acting as natural buffers between the mountains and urbanized areas. However, areas at the base of slopes remain vulnerable to rockfalls and debris flows, especially during periods of intense rainfall or seismic activity.

Soils in the region vary in their susceptibility to slope failure. Loose, unconsolidated sediments, such as those found on alluvial fans, may experience movement due to liquefaction or erosion. In contrast, fractured bedrock in the Santa Rosa Mountains can fail along existing planes of weakness, particularly when subjected to ground shaking or weathering processes.

Seismically Induced Landslides: Strong earthquakes can trigger landslides in steeply sloped areas by causing rapid ground shaking that reduces soil cohesion and destabilizes slopes. A peak ground acceleration of 0.10g or greater is typically required to induce earthquake-related slope failures. Given that the region is located near active faults, including the San Andreas Fault and the San Jacinto Fault, Cathedral City is at risk of experiencing seismically induced landslides in areas with vulnerable topography.

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Intense shaking can also lead to rockfalls, particularly on steep ridges such as Edom Hill. Rockfalls occur when weathered or fractured rock becomes dislodged and falls due to the force of gravity. Areas with high concentrations of boulders or loose rock are especially at risk.

Rainfall-Induced Landslides and Debris Flows: Heavy precipitation can saturate soils, reducing their cohesion and leading to slope failure. This is particularly concerning in post-wildfire environments, where vegetation loss increases the potential for soil erosion and runoff. Burned areas can become sources of debris flows, in which fast-moving mixtures of water, soil, and rock travel downslope with destructive force.

Climate change projections suggest that extreme rainfall events may become more frequent in California, increasing the likelihood of rain-triggered landslides in Cathedral City. Areas with loose or poorly compacted soils are especially vulnerable during intense storm events Location and Geographic Extent
Landslides in Cathedral City are primarily associated with the slopes of the Santa Rosa Mountains and the Indio Hills, which exhibit moderate to high susceptibility to rockfalls and slope failures due to their geologic composition and steep inclines. The metasedimentary and intrusive rocks in these regions contain planes of weakness, including fractures, joints, and foliation, which contribute to instability, particularly during seismic events or intense rainfall.

The areas most at risk for landslides are those adjacent to steep slopes, where rockfalls and debris flows could impact developed and undeveloped lands. The highest-risk locations include the eastern and northeastern slopes of the Santa Rosa Mountains and sections of the Indio Hills, where weathering processes create precariously perched boulders susceptible to failure. The East and West Cathedral Canyon Washes act as natural buffers, helping to mitigate the effects of slope instability by absorbing falling debris and providing some protection to habitable structures.

Earthquake-induced slope failures are a significant concern due to the proximity of active faults, including the San Andreas Fault and the San Jacinto Fault. Seismically induced landslides are most likely to occur in areas experiencing peak ground accelerations above 0.10g, which is within the range of seismic activity projected for Cathedral City. Additionally, engineered slopes and cut-and-fill constructions on the valley floor may also be vulnerable if not designed to withstand seismic shaking.

Magnitude and Severity
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The magnitude of a landslide’s impact depends on its size, location, and the proximity of vulnerable structures or infrastructure. In Cathedral City, areas at the base of steep slopes - Source: California Geological Survey Map Sheet 58: Deep-Seated Landslide Susceptibility Local Hazard Mitigation Plan Update
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particularly along the edges of the Santa Rosa Mountains and Indio Hills - are susceptible to rockfall and debris flow hazards. These hazards pose risks to roadways, utility lines, and the Cove neighborhood, where residential development lies near the base of unstable slopes. The East and West Cathedral Canyon Washes function as natural drainage channels and can absorb limited debris from slope failures, offering partial protection to adjacent areas during moderate events.

The Santa Rosa Mountains and Indio Hills contain zones with moderate to high landslide susceptibility, particularly where fractured or jointed bedrock is exposed. The severity of slope failure events in Cathedral City is influenced by both natural and human-induced factors, including earthquake ground shaking, intense or prolonged rainfall, and grading or construction on unstable terrain.

Seismically induced landslides and rockfalls are a key concern given the city’s proximity to multiple active faults. The San Andreas Fault, which runs near the Coachella Valley, is capable of producing earthquakes in excess of magnitude 7.0, with peak horizontal ground accelerations (PGA) in Cathedral City ranging from 0.45g to 0.9g, according to USGS models. Ground shaking at these levels could dislodge unconsolidated slope materials and fractured rock in the Santa Rosa foothills and nearby ridgelines. Additionally, areas underlain by unconsolidated alluvial deposits may be subject to seismically induced ground failure, including settlement or lateral spreading.

Rainfall-triggered landslides are also a concern, particularly during extreme precipitation events such as atmospheric rivers or tropical storms. Although Cathedral City experiences relatively low annual rainfall due to its arid Sonoran Desert climate, high-intensity storms can saturate loose soils, especially on unvegetated or recently disturbed slopes. This can increase the probability of debris flows or shallow landslides.

Of growing significance is the risk of mudflow and debris transport from burned areas outside Cathedral City. During Tropical Storm Hilary in August 2023, significant volumes of sediment, rocks, and mud were transported from burn scars in the Santa Rosa Mountains, more than 25 miles away.

These debris flows overwhelmed regional drainage infrastructure, causing road closures and sediment deposition in downstream areas. Although Cathedral City was not within the burn area, the city received mud and sediment from upstream flows, highlighting the need to address post-wildfire hydrologic and geomorphic impacts in slope hazard mitigation. These transboundary flow risks are projected to increase under climate-driven changes to wildfire frequency and storm intensity.

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Historical Occurrences
FEMA Disaster Declarations
Incident
Subcategory County FEMA Declaration String
Calendar Year of
Declaration
Date
Month
Declaration
Date
Declaration
Title State
None None None None None None None None
California Governor-declared Declarations

DATE OF DISASTER TYPE OF DISASTER COUNTIES INVOLVED
None None None
List of Governor-declared disasters for property tax purposes since 1991. Source: California State Board of Equalization While there are no records of large catastrophic landslides directly within Cathedral City’s developed areas, documented incidents of rockfalls and slope instability have occurred following seismic events, particularly along highways adjacent to steep terrain. The escarpment along East Palm Canyon Drive has been identified as a hazard area, where falling rock during earthquakes has posed a threat to motorists and infrastructure. Historically, intense seismic events in the broader Coachella Valley region have resulted in localized landslides and rockfalls, with several faults in the area capable of generating peak ground accelerations sufficient to trigger slope failures. Given these conditions, Cathedral City has been assessed as having a moderate to high potential for seismically induced landslides, particularly in undeveloped lands near the Santa Rosa Mountains and on steep ridges such as Edom Hill, where past seismic activity has led to recurrent rockfall hazards.

Probability and Effects of Future Conditions
Overall probability over next five years: Moderate.

The probability of future landslides in Cathedral City is influenced by a combination of natural and human-induced factors, including seismic activity, extreme precipitation events, and slope instability.

While the city is primarily located on relatively flat desert terrain, certain areas, particularly near the Santa Rosa Mountains and Indio Hills, have a moderate to high susceptibility to landslides, especially during seismic events or following heavy rainfall.

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Seismically induced landslides are a significant concern due to Cathedral City’s proximity to multiple active fault zones, including the San Andreas Fault and the San Jacinto Fault. Ground accelerations of at least 0.10g in steep terrain can trigger slope failures, rockfalls, and debris slides. Studies have shown that certain segments of the Santa Rosa Mountains contain highly fractured or jointed bedrock, making them prone to rockfalls, particularly during strong ground shaking.

Climate change is also expected to influence landslide probability in Cathedral City. While the region has an arid climate with minimal annual rainfall, the increasing intensity of atmospheric river events could lead to higher precipitation levels in short periods, increasing soil saturation and the risk of debris flows. Periods of extreme drought followed by heavy rain can destabilize slopes, further heightening landslide risks. Additionally, wildfires, which are becoming more frequent and severe in Southern California, contribute to slope instability by reducing vegetative cover that helps hold soil in place.

Future development and land use changes in hillside areas near the Santa Rosa Mountains may further increase susceptibility to landslides if appropriate geotechnical assessments and mitigation measures are not implemented. Engineering solutions such as slope reinforcement, proper drainage systems, and vegetation management can help reduce landslide risks in vulnerable areas. However, as development expands into terrain with moderate to high susceptibility to landslides, continuous monitoring and adherence to updated building codes will be necessary to mitigate potential impacts.

The potential effects of future landslides include damage to infrastructure, road closures, and disruptions to essential services. Areas near the foothills of the Santa Rosa Mountains and Indio Hills, as well as sections of Highway 111 and other roadways adjacent to unstable slopes, may experience periodic closures due to rockfalls or debris flows. Landslides in these areas could also impact utilities, including water and power lines, further exacerbating the consequences of such events.

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3.3.11 Sandstorms
Description
Sandstorms in Cathedral City are characterized by strong wind events that lift and carry large amounts of fine dust, sand, and particulate matter across roadways, open land, and developed areas. These events include haboobs-fast-moving walls of dust triggered by downdrafts from collapsing thunderstorms-and persistent blowsand conditions, which occur when dry, loose sand is mobilized by high sustained winds, often from the northwest.

Blowsand is a chronic hazard in the Coachella Valley, particularly along roadways such as Interstate 10, Varner Road, Gene Autry Trail, and Vista Chino, where wind-driven sand can accumulate on pavement, obscure visibility, and cause significant disruptions to transportation, public safety, and health. Unlike haboobs, which are rapid-onset events associated with summer monsoons, blowsand typically occurs under sustained wind conditions from November through May and may persist for hours or even days.

Fine particulate matter (PM10 and PM2.5) carried in sandstorms poses serious health risks, especially to individuals with asthma, chronic respiratory disease, cardiovascular illness, or other pre-existing health conditions. In Cathedral City, this hazard intersects with regional air quality concerns, which already place the city in non-attainment status under federal clean air standards due to desert dust and transported pollution.

While sandstorms rarely cause direct structural damage, they frequently lead to traffic accidents, road closures, vehicle damage, and utility disruptions, particularly along power lines and substations exposed to high dust loads. Recurrent sand accumulation also increases roadway maintenance costs and decreases visibility for both emergency and commercial traffic, presenting operational hazards for first responders and freight carriers.

Location and Geographic Extent
Sandstorms in Cathedral City primarily affect areas with exposed sandy soils, minimal vegetation cover, and direct alignment with prevailing northwesterly winds. These events are most common in the northern and eastern portions of the city, particularly adjacent to major wind corridors and desert washes.

The most affected locations include:

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• Varner Road and Interstate 10 Corridor: High vulnerability zone for both visibility-related vehicle collisions and sand deposition across roadways. Wind-driven sediment often originates from open land west of Palm Drive and north of Vista Chino. • Whitewater River Channel: Functions as a conduit for wind-driven sand transport, particularly where the channel intersects with infrastructure east of Date Palm Drive and near Cathedral Canyon Drive.
• North Cathedral City Open Spaces: Undeveloped or sparsely vegetated parcels between Mountain View Road, Rio Vista Elementary School, and the Desert Princess Golf Course frequently experience localized sand deposition.
• Edom Hill Area: Located on the city’s northern boundary, this area is prone to both wind erosion and terrain-amplified gusts, making it a significant origin point for episodic sand transport during high-wind events.

Winds in the Coachella Valley frequently exceed 25–35 mph, with gusts over 50 mph recorded at nearby weather stations (e.g., Palm Springs International Airport and CVAG’s Indio wind monitor).

Sandstorms typically develop during Santa Ana wind conditions or during cold frontal passages when desert wind gradients intensify.

Relationship to Land Use and Development
Blowsand hazards are closely tied to land use decisions and the amount of disturbed or unprotected soil in urban fringe areas. In Cathedral City, the expansion of urban development along the city’s north and east periphery-particularly in the Panorama, north of Vista Chino, and Varner Road areas-has increased exposure to sand-laden winds from open space and alluvial fan terrain.

Unpaved lots, vacant parcels, and transitional areas between development and desert terrain act as source zones for fine particulate matter. These are especially vulnerable during construction activity, grading, or utility trenching. Developments adjacent to the Whitewater River floodplain and historic wind-transport corridors are particularly at risk for both sand deposition and chronic dust accumulation.

The Coachella Valley Association of Governments (CVAG) has emphasized in its Blowsand and Flood Risk Study (2021) that unmanaged edge conditions between urban and undeveloped land magnify sand transport. Vegetation removal, compacted soils, and altered drainage patterns further contribute to sediment mobilization during high-wind events.

Future development, if not properly mitigated through design and site planning, may increase longterm exposure. Cathedral City’s zoning code and future updates to its General Plan should consider Local Hazard Mitigation Plan Update
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incorporating blowsand risk overlays, windbreak design standards, and construction-phase stabilization requirements (e.g., mulch, temporary barriers, and native vegetation buffers) to minimize downstream impacts on road safety, air quality, and infrastructure maintenance.

Magnitude and Severity
Sandstorms in Cathedral City vary in intensity, with severity primarily determined by wind speed, duration, soil particle concentration, and visibility reduction. The most disruptive sandstorm events typically occur when wind gusts exceed 40–50 mph and surface soil conditions are dry and unconsolidated. These conditions frequently occur during Santa Ana wind events in the fall and early winter, and during frontal passages in the spring.

The severity of impacts is concentrated in three domains:
• Transportation Safety: Sand deposition across major arterials such as Varner Road, Date Palm Drive, and Interstate 10 can reduce visibility to less than ¼ mile, qualifying as a visibilityobstructing sandstorm under the National Weather Service definition. These events increase the risk of multi-vehicle accidents and can result in highway closures. According to Caltrans and CHP incident logs, sand-related closures have occurred multiple times in the Varner/I-10 corridor in recent years.
• Public Health: Fine particulate matter (PM₁₀ and PM₂.₅) carried by sandstorms poses respiratory risks, especially for individuals with asthma, chronic obstructive pulmonary disease (COPD), or cardiovascular conditions. The South Coast Air Quality Management District (SCAQMD) frequently issues Windblown Dust Advisories in the Coachella Valley during severe wind events. Blowsand can trigger local AQI (Air Quality Index) levels to exceed 150 (Unhealthy), particularly in downwind areas such as Cathedral City's Panorama and Cove Districts.
• Infrastructure Impacts: Accumulation of sand in gutters, storm drains, HVAC systems, and solar panel surfaces can degrade performance and increase maintenance costs. Repetitive sand incursion events have prompted the city’s Public Works Department to develop rapid response sand removal protocols along critical corridors and near stormwater intakes.

The severity of individual sandstorm events can be quantified using proxies such as:
• Wind Speed (mph): Events with sustained speeds above 25 mph and gusts over 40 mph are typically associated with sand transport.

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• Particulate Concentration: PM₁₀ levels exceeding 150 µg/m³ over 24 hours, as measured by SCAQMD air monitoring stations, indicate significant health hazards. • Visibility Reduction (miles): Visibility below 0.5 miles over a sustained period triggers National Weather Service advisories for blowing dust or sand.

In extreme cases, sandstorm events may be classified by the National Weather Service as “Haboobs”, involving rapidly advancing walls of dust that reduce visibility to near zero in minutes.

While less common than in Arizona, haboob-like conditions have been recorded in the Coachella Valley-most notably during a July 2018 wind event that generated sustained winds of 60 mph and closed segments of I-10.

Historical Occurrences
FEMA Disaster Declarations
Incident
Subcategory County FEMA Declaration String
Calendar Year of
Declaration
Date
Month
Declaration
Date
Declaration
Title State
None None None None None None None None
California Governor-declared Declarations

DATE OF DISASTER TYPE OF DISASTER COUNTIES INVOLVED
None None None
List of Governor-declared disasters for property tax purposes since 1991. Source: California State Board of Equalization Cathedral City and the surrounding Coachella Valley have experienced multiple sandstorm and blowsand events over the past two decades. While not typically recorded as federally declared disasters, these events have resulted in road closures, air quality advisories, traffic accidents, and localized infrastructure impacts. Key historical incidents include:
• July 9, 2018 – Coachella Valley Sandstorm Event: A sudden wind event with gusts exceeding 60 mph resulted in a fast-moving wall of sand and dust sweeping through Cathedral City, reducing visibility to less than ¼ mile. The event prompted closure of eastbound I-10 between Gene Autry Trail and Date Palm Drive. Local police and fire units responded to multiple traffic collisions and stalled vehicles due to zero-visibility conditions. Air quality levels measured at the Palm Springs monitoring station exceeded 170 AQI (Unhealthy) for PM₁₀.

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• March 6–7, 2017 – Spring Wind Event: Prolonged high winds generated widespread blowsand along Varner Road, impacting traffic circulation and temporarily halting SunLine Transit services along key routes. The Public Works Department initiated emergency sand clearance operations to maintain arterial function.
• October 13, 2014 – Santa Ana Wind Event: Sustained winds of 30–40 mph, with gusts exceeding 50 mph, transported large volumes of sand from unpaved areas east of Cathedral City. Blowsand accumulation was recorded on streets in the Dream Homes and Rio Vista neighborhoods. This event was associated with multiple power outages and temporary school closures due to indoor air quality concerns.
• April 21, 2010 – Dust and Blowsand Advisory: The National Weather Service (NWS) issued a regional Blowing Dust Advisory for Riverside County. Winds exceeding 45 mph created sand drifts on I-10 and SR-111, prompting Caltrans to deploy road crews for sand removal and traffic management. PM₁₀ concentrations exceeded 200 µg/m³ at local air monitoring stations.
• Annual Recurrence Patterns: Based on historical weather data from the Western Regional Climate Center and Caltrans maintenance logs, sandstorm or blowsand events occur 3–6 times per year, with higher frequency in spring (March–May) and fall (September–November). These events typically align with Santa Ana wind patterns or pre-frontal passage conditions that accelerate wind flow through the San Gorgonio Pass.

Cathedral City’s location east of open desert terrain and near active wind corridors such as Varner Road and the Whitewater River channel contributes to elevated exposure. Unpaved lots, agricultural lands, and disturbed development sites within and near city boundaries continue to serve as origin points for sediment mobilization during these wind events.

Probability and Effects of Future Conditions
Overall probability over next five years: Likely.

The probability of future sandstorm events, including both large-scale haboobs and localized blowsand episodes, in Cathedral City is classified as “Likely”, consistent with FEMA’s frequency definition of events that are expected to occur at least once every three years. Based on historical climate records, wind speed trends, and recent NWS advisories, Cathedral City experiences 3–6 significant sand transport events annually, particularly along known high-risk corridors such as Varner Road, Date Palm Drive, and the Whitewater River wash.

Climatic Trends and Drivers: Projected increases in drought severity, declining soil moisture, and longer dry seasons in Southern California-linked to regional climate change-are expected to Local Hazard Mitigation Plan Update
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exacerbate conditions conducive to sand and dust transport. The Fourth California Climate Change Assessment (Inland Deserts Region) identifies increasing wind-driven particulate events in the Coachella Valley due to the following compounding factors:
• Increased frequency and duration of high-wind events during transitional seasons (spring and fall).
• Expansion of exposed soils due to prolonged drought, fallow agricultural fields, and postwildfire burn scars. • Land use change and disturbance from new development and deferred dust control on vacant parcels.

Modeling from the South Coast Air Quality Management District (SCAQMD) indicates that PM₁₀ levels in Riverside County’s desert areas may exceed federal thresholds more frequently under midand high-emissions scenarios by 2045, especially during Santa Ana wind conditions.

Future Exposure and Development Patterns: As Cathedral City continues to develop vacant or underutilized land on its eastern edge-especially near the Varner Road corridor, Whitewater Channel, and Edom Hill foothills-construction activity and land disturbance are likely to temporarily increase local susceptibility to sand entrainment and migration. Without adequate stabilization measures, such as revegetation or dust suppression controls, these areas may contribute to more frequent or severe blowsand events.

Additionally, future climate and land-use changes may result in:
• More frequent road closures due to sand accumulation on key arterials (especially I-10, Varner Road, and 30th Avenue).
• Elevated public health impacts from prolonged PM₁₀ exposure, particularly among vulnerable populations with pre-existing respiratory conditions.
• Increased infrastructure maintenance costs for sand removal, street sweeping, and HVAC filtration system replacements at public facilities.

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3.3.12 Transportation-Related Disruptions
Description
Cathedral City faces a variety of transportation-related disruption risks tied to the limited redundancy of its roadway network, regional dependence on Interstate 10 (I-10), proximity to high-frequency rail traffic, and proximity to air corridors and operations associated with Palm Springs International Airport (PSP). Disruptions to transportation systems-whether caused by flood, earthquake, mudflow, accidents, mechanical failure, or cascading hazards such as wildfire or sandstorms-can significantly impact emergency response, resident mobility, goods movement, and regional economic continuity.

The city is bisected and bounded by several critical corridors, including I-10, State Route 111 (SR-111), Date Palm Drive, Gene Autry Trail, and Dinah Shore Drive. Many of these corridors lack functional detour alternatives in the event of closures. During Tropical Storm Hilary in 2023, for example, multiple I-10 exits were rendered impassable due to mudflows and water damage, stranding travelers and emergency vehicles. Similar disruptions have occurred during past seismic and flood events, exacerbated by the region’s topography and limited east-west redundancy.

Additionally, Cathedral City lies adjacent to the Union Pacific (UP) Railroad main line, one of the busiest freight corridors in the western United States. An estimated 50 to 100 freight trains traverse the Coachella Valley daily between Colton Crossing and Yuma, Arizona. This includes hazardous materials shipments and heavy cargo that, if derailed, could result in substantial threats to life, infrastructure, Local Hazard Mitigation Plan Update
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and environmental safety. Though derailments are infrequent, their potential severity requires inclusion in regional hazard mitigation planning.

Air transportation represents another critical dimension of transportation vulnerability. Cathedral City is approximately 5 miles southeast of Palm Springs International Airport (PSP), which served over 3.2 million passengers in 2024 and is projected to exceed 6 million by 2042. While the airport is located outside of Cathedral City's jurisdiction, its proximity and role as an emergency coordination hub and economic driver mean that disruptions-whether due to wildfire smoke, flood, airspace incidents, or security events-can affect regional mobility and response operations.

Transportation-related disruptions pose particular challenges for Cathedral City’s emergency evacuation planning, supply chain continuity, and access to healthcare and emergency services. This is especially relevant for populations with mobility constraints, those living in hillside or cul-de-sac developments, and areas with limited ingress and egress points, such as the Cove District, portions of north Cathedral City, and neighborhoods adjacent to Edom Hill.

Planned infrastructure projects, including the proposed Coachella Valley–Los Angeles passenger rail line, will add future transportation options but may also introduce new safety and coordination considerations. Hazards affecting any component of this multimodal system-roadways, rail, or air-may ripple through Cathedral City’s built environment and community systems, requiring robust contingency planning and interagency coordination.

Location and Extent
Transportation-related disruptions can occur citywide but are most acute along Cathedral City’s limited east–west and north–south corridors, which serve as the primary conduits for regional mobility, emergency response, and goods movement. The most critical transportation infrastructure includes:
• Interstate 10 (I-10): A federally designated Strategic Highway Network (STRAHNET) route and major freight and evacuation corridor. Closures along I-10 impact all of Cathedral City, particularly when alternate routes such as Varner Road or Ramon Road are simultaneously affected by storm, debris, or crash events.
• State Route 111 (SR-111): A key arterial that links Cathedral City with Palm Springs and Rancho Mirage. SR-111 is susceptible to closure due to flooding, sand accumulation, and stormwater damage.

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• Union Pacific Railroad Corridor: This active freight rail line runs north of Cathedral City and carries hazardous cargo. The corridor is vulnerable to derailment risk, particularly in segments with aging infrastructure or exposure to seismic shaking. • Gene Autry Trail, Date Palm Drive, and Cathedral Canyon Drive: These city roadways serve as vital local connectors and are used heavily during I-10 closures or detours. They are vulnerable to flood inundation and post-storm debris deposition.
• Palm Springs International Airport (PSP): Although outside city limits, PSP is less than 5 miles from Cathedral City’s civic center and is a key access point for residents, tourists, and emergency services.

Relationship to Land Use and Development
The transportation network intersects directly with Cathedral City’s residential, commercial, and industrial development patterns. Residential neighborhoods such as the Cove, Panorama, and Century Park are built along or near key arterial roadways and would be significantly affected by road closures, particularly during emergency evacuations. Industrial and warehouse development is concentrated in the southwestern and northern portions of the city, adjacent to both rail and freeway infrastructure, increasing the potential consequences of disruptions related to derailments or hazmat spills.

Many of Cathedral City’s commercial corridors-particularly along East Palm Canyon Drive (SR-111) and Date Palm Drive-depend on uninterrupted roadway access for supply deliveries, customer access, and business continuity. Similarly, development near the Whitewater River Stormwater Channel must account for both hydrologic and transportation vulnerabilities, given the flood-prone nature of adjacent roadways and crossings.

Recent growth and future development near Varner Road, Rio del Sol Road, and within North City Specific Plan areas are expanding into zones with limited existing transportation redundancy. These areas require targeted planning to integrate emergency ingress/egress, storm-resilient design, and coordination with regional evacuation strategies.

The expansion of regional rail service through the proposed Coachella Valley–Los Angeles rail project will also necessitate new planning considerations, including grade separation, emergency response access to track-adjacent areas, and coordination with existing road networks. Development near the proposed corridor-especially in northern Cathedral City-must be evaluated for exposure to both service disruptions and potential derailment hazard buffers.

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Magnitude and Severity
Transportation-related disruptions in Cathedral City can range from minor delays and detours to fullscale regional emergencies that isolate entire sections of the city. The severity of these disruptions depends on the type of incident, the location within the transportation network, and the presence-or absence-of redundant access routes.

Incidents of moderate to high severity are most commonly associated with:
• Storm-related roadway washouts, mudflows, and debris blockages, particularly along Gene Autry Trail, Vista Chino, and Cathedral Canyon Drive during monsoonal rain events or postfire debris flows. • Rail derailments, especially those involving hazardous cargo such as flammable liquids or pressurized gases. Though less frequent, these events have high consequence potential due to proximity to residential neighborhoods and arterial roadways. A hazardous materials derailment could trigger shelter-in-place orders or evacuations over a wide area. • Air transportation disruptions linked to Palm Springs International Airport (PSP), which can impact emergency medical transport, regional logistics, and evacuation efforts during widearea disasters. Delays or closures at PSP are often related to strong wind events (e.g., Santa Ana conditions) or low-visibility conditions caused by sand and dust. • Traffic collisions or hazmat spills on I-10 or SR-111, which can result in extended freeway closures and rerouting through local surface streets, overwhelming local capacity and delaying emergency response.

The impacts of these disruptions extend beyond mobility. In events where I-10, SR-111, or Varner Road are simultaneously compromised, Cathedral City faces a temporary loss of regional access, with cascading effects on:
• Emergency response and evacuation coordination.
• Supply chain continuity, particularly for fuel, medical supplies, and food distribution. • Economic activity, as retail centers, hospitality corridors, and industrial sites become inaccessible.

Severity is also heightened by Cathedral City’s limited number of east–west and north–south arterial routes, making even localized blockages or traffic incidents consequential for community-wide access.

Notably, during Tropical Storm Hilary (2023), multiple freeway and arterial exits were closed between Washington Street and Highway 111, severely limiting regional egress.

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Based on FEMA’s Threat and Hazard Identification and Risk Assessment (THIRA) methodology, the severity scale for transportation-related disruptions in Cathedral City can be summarized as:
• Low Severity (frequent): Short-term congestion or local road detours (e.g., due to traffic collisions or minor flooding).
• Moderate Severity (periodic): Extended road closures due to flooding, debris flow, or multivehicle accidents requiring detour implementation. • High Severity (infrequent): Multi-day closures of regional routes (e.g., I-10), hazmat-related derailments or spills, or airport shutdowns that impact emergency logistics and public safety.

The California Department of Transportation (Caltrans) has identified SR-111 and I-10 as vulnerable to stormwater and debris flow hazards in regional adaptation plans, with both corridors serving as lifelines for the Coachella Valley.

The California State Hazard Mitigation Plan (2023) also recognizes transportation network vulnerability-particularly in inland desert regions-as a key interdependency risk in the context of climate change, seismicity, and extreme weather.

Historical Occurrences
FEMA Disaster Declarations
Incident
Subcategory County FEMA Declaration String
Calendar Year of
Declaration
Date
Month
Declaration
Date
Declaration
Title State
None None None None None None None None

California Governor-declared Declarations

DATE OF DISASTER TYPE OF DISASTER COUNTIES INVOLVED
None None None
List of Governor-declared disasters for property tax purposes since 1991. Source: California State Board of Equalization Cathedral City has experienced multiple significant transportation-related disruptions in recent years, often triggered by extreme weather events, seismic conditions, or infrastructure failures. These disruptions have affected local and regional mobility, emergency response access, and goods movement throughout the Coachella Valley.

Key historical incidents include:

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• Tropical Storm Hilary (August 2023): This rare tropical storm brought intense rainfall to Cathedral City and the surrounding region, causing widespread flooding and debris flows.

Nearly all eastbound and westbound I-10 exits between Washington Street and SR-111 were impassable for several hours due to floodwaters and mud deposits. Key arterial routes including Vista Chino, Gene Autry Trail, and Cathedral Canyon Drive were also closed, creating citywide access challenges and delaying emergency services.
• January 2019 Windstorm and Sand Event: High winds exceeding 60 mph led to visibilityrelated road closures along I-10 near Date Palm Drive and SR-111 through Palm Springs and Cathedral City, disrupting commuter and freight movement. Blowing sand created hazardous conditions for both vehicles and pedestrians and temporarily halted travel through the Varner Road corridor.
• Union Pacific Freight Train Delays and Disruptions: Although no major derailments have occurred in Cathedral City to date, freight traffic of 50 to 100 trains per day on the Union Pacific mainline-running parallel to I-10-has been subject to service interruptions due to weather, track obstructions, or downstream infrastructure issues. A significant train derailment near Mecca in 2015 led to service suspensions that affected regional cargo and supply chains, with indirect impacts on Coachella Valley distribution timelines. • July 2013 Flash Flooding: A monsoonal downpour caused a rapid rise in Cathedral Canyon Wash, leading to the temporary closure of Cathedral Canyon Drive south of Dinah Shore Drive.

Adjacent properties experienced localized access constraints due to water over roads and sediment deposition.
• PSP Airport Weather Delays: Palm Springs International Airport (PSP), just northwest of Cathedral City, has experienced multiple wind-related flight cancellations and diversions, particularly during Santa Ana wind events or low-visibility conditions tied to sand and dust.

While PSP remains a critical emergency and passenger hub for the region, its proximity to hazard-prone corridors adds operational vulnerability.

While catastrophic incidents like large-scale train derailments or air transport crashes have not occurred in Cathedral City, the cumulative impact of recurring roadway disruptions, extreme weather, and freight delays highlights the vulnerability of the city’s transportation network.

Given these patterns and the projected increase in extreme weather due to climate change, historical trends underscore the need for investment in redundant infrastructure, interagency coordination, and emergency traffic management.

Probability and Effects of Future Conditions
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Overall probability over next five years: Moderate.

The probability of future transportation-related disruptions in Cathedral City is considered moderate, with frequency and severity influenced by a combination of climate-related hazards, seismic vulnerability, and the City’s reliance on a limited number of critical roadways and utility corridors. As population growth, regional travel, and freight volumes increase across the Coachella Valley, the city’s exposure to transportation disruption risks is also expected to rise.

Several trends influence future risk:
• Extreme Weather Intensification: Projected increases in extreme heat, intense rainfall, and high wind events will likely result in more frequent roadway washouts, flood-induced closures, and visibility reductions due to sand and debris. According to California’s Fourth Climate Change Assessment, storm intensity is projected to increase by up to 15–20% by mid-century, with implications for roadway drainage and slope stability. • Limited Redundant Roadway Network: Cathedral City’s internal circulation system is dependent on a small number of north-south corridors (e.g., Date Palm Drive, Cathedral Canyon Drive, Landau Blvd) and east-west routes (e.g., Dinah Shore Drive, Vista Chino, Ramon Road). During Tropical Storm Hilary in 2023, simultaneous closures of multiple crossings over the Cathedral Canyon Wash and Whitewater River demonstrated the vulnerability of this constrained network. As development continues along foothill zones and eastern edges of the city, the demand for reliable alternate evacuation and supply routes will increase. • Increased Freight and Rail Traffic: With 50 to 100 Union Pacific freight trains per day passing through the region and proposals for new intercity passenger rail service between Los Angeles and the Coachella Valley, the likelihood of system stress and cascading delays from derailments, collisions, or infrastructure failure will increase-particularly during multi-hazard events such as earthquakes or flooding.
• Proximity to Palm Springs International Airport (PSP): PSP’s projected growth to 6.4 million annual passengers by 2042 will elevate the regional significance of uninterrupted surface access to the airport. During high wind or flooding events, roadway closures on Vista Chino and Gene Autry Trail can restrict airport access, posing both economic and emergency response challenges.
• Seismic and Post-Earthquake Access Constraints: Cathedral City’s transportation infrastructure-particularly bridges and culverts crossing natural washes and flood channelsmay be vulnerable to closure or damage following a major earthquake. Inaccessibility of key routes during post-disaster response windows would hinder evacuation, firefighting, and supply distribution efforts.

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Future conditions also indicate that transportation disruptions could intersect with socioeconomic vulnerability, disproportionately affecting transit-dependent, elderly, disabled, and low-income residents who may lack immediate access to private vehicles or alternative routes during emergencies.

These populations are more likely to reside in areas where redundant access is limited, and service restoration may be delayed.
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SECTION 4 – VULNERABILITY ASSESSMENT
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Element B: Risk Assessment Requirements
B2. Does the plan include a summary of the jurisdiction's vulnerability and the impacts on the community from the identified hazards? Does this summary also address NFIP insured structures that have been repetitively damaged by floods? (Requirement 44 CFR § 201.6(c)(2)(ii))

4.1 Introduction
Vulnerability assessments are critical tools for identifying the people, infrastructure, and assets most at risk from natural and human-caused hazards. By systematically analyzing how hazards interact with community characteristics such as demographics, land use, critical facilities, and environmental conditions, the assessment helps determine who and what are most vulnerable to disasters.

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4.2 Hazard-Specific Vulnerability Analysis

4.2.1 Extreme Heat
Overall Vulnerability and Impact
Cathedral City faces mounting vulnerability to extreme heat events as a result of rising global temperatures and localized urban heat island (UHI) effects. According to Cal-Adapt and the California Fourth Climate Change Assessment, average annual temperatures in the region are projected to increase by 4.4°F to 5.8°F by 2050 under high-emissions scenarios (RCP8.5). The city already experiences summer highs that frequently exceed 110°F, and by mid-century, Cathedral City could face an average of 32 days per year above 111.9°F, compared to just 7 days in 1990.

In addition to direct health impacts-such as heat exhaustion, heat stroke, and dehydration-extreme heat compounds air quality degradation, electricity demand, and regional drought stress. The city’s physical landscape-including widespread impervious surfaces, large asphalt parking lots, and industrial zones concentrated along East Palm Canyon Drive, Perez Road, and the Date Palm Drive corridorfurther intensifies local surface temperatures. The city’s limited tree canopy cover, particularly in commercial and industrial areas, amplifies heat stress for both built infrastructure and vulnerable residents.

Population Exposure
The entire population of Cathedral City is exposed to the risks of extreme heat. However, risk is not evenly distributed. High-Social Vulnerability Index (SVI) census tracts-especially in the Cove neighborhood, Dream Homes, and areas north of Vista Chino-experience greater exposure due to older housing stock, limited shade, and fewer private cooling systems.

Critical Facilities
Critical facilities such as Southern California Edison substations, CVWD and DWA water infrastructure, and emergency operations centers face operational pressure under prolonged heat conditions. While heat itself does not structurally damage these facilities, it drives peak load stress on electrical systems and increases the probability of rotating outages or system faults. During high heat days, air conditioning demand can spike significantly, and if outages occur, essential facilities-including fire stations, cooling centers, and the Cathedral City Senior Center-may be compromised.

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Water and wastewater systems are also impacted. Heat can reduce pumping efficiency, raise water temperatures, and impair chemical treatment processes, particularly in older facilities such as those serving the city's east and northeast service areas. Sustained high temperatures may also reduce pressure in overhead transmission systems, limiting regional power flow.

Non-Critical Facilities
Schools such as Cathedral City High School and James Workman Middle School face heat-related risks due to aging HVAC systems and outdoor campus designs with minimal shade. Commercial and industrial facilities along Perez Road and Ramon Road corridors also report rising energy costs and indoor temperature hazards, especially where facilities lack modern insulation or cooling retrofits.

Increased heat also reduces workplace productivity in warehousing and manufacturing sectors, which represent a substantial share of the city's employment base. Construction crews, outdoor logistics teams, and auto center employees are especially vulnerable to midday heat exposure.

Environmental Impacts
Extreme heat has multifaceted environmental impacts in Cathedral City:
• Urban Heat Island Intensification: Industrial surfaces, unshaded arterial roads like East Palm Canyon Drive and Gerald Ford Drive, and concrete-heavy developments increase local ambient temperatures by up to 8°F compared to surrounding natural landscapes. • Air Quality Degradation: High temperatures contribute to ground-level ozone formation, worsening respiratory conditions, particularly for children and elderly residents in high-traffic corridors.
• Water Supply Stress: Increased cooling demand accelerates municipal water use, while ongoing drought conditions reduce supply resilience from the Coachella Valley Aquifer and Colorado River allocations.

Changes in Development Since Last Approved Plan
Development Trends: Since the 2018 LHMP, Cathedral City has experienced continued industrial and commercial growth, particularly north of Interstate 10 and along Date Palm Drive. This development has increased impervious surface area, contributing to urban heat retention and localized exposure to extreme heat events.

Land Use and Zoning: No new zoning ordinances or land use policies have been adopted to address extreme heat through urban forestry requirements, green infrastructure standards, or reflective Local Hazard Mitigation Plan Update
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(albedo-enhancing) building materials. Tree canopy coverage remains limited, especially in commercial zones and multi-family residential areas.

Population Shifts: The proportion of residents aged 65 and older has increased to approximately 18.4% of the total population (ACS 2022). This demographic trend heightens the city’s vulnerability to extreme heat events due to age-related sensitivity, chronic health conditions, and reliance on air conditioning systems during prolonged heatwaves.

Impacts on Vulnerable Populations
Low-Income Residents: Many households in Cathedral City-particularly in central and eastern census tracts-lack access to efficient cooling systems. High utility costs may lead residents to reduce air conditioning use, resulting in unsafe indoor temperatures during prolonged heat events. These areas align closely with high-SVI designations and older rental housing stock.

Elderly Individuals: Seniors are at elevated risk of heat-related morbidity and mortality. Many live in single-story homes or mobile home parks without central air or sufficient insulation. Social isolation further impairs emergency response and cooling access.

People with Disabilities: Individuals reliant on electrically powered devices (e.g., ventilators, CPAP machines, motorized wheelchairs) are at high risk if rolling blackouts or outages occur during heat events. Mobility impairments also limit access to designated cooling centers such as the Cathedral City Library or Senior Center, especially without family or transit assistance.

Outdoor Workers: The city’s logistics, maintenance, and construction workforce is frequently exposed to high surface temperatures during peak summer months. Without scheduled hydration breaks, shade, and heat training, workers remain at elevated risk of heat exhaustion and productivity loss. These impacts are particularly acute in areas under active development such as the North City Specific Plan area.

Unhoused Individuals: The city's unhoused population, estimated at 82 individuals in the latest PIT Count, is highly exposed during heatwaves. Many individuals reside near commercial corridors, flood channels, and freeway underpasses, where radiant heat from asphalt and metal structures intensifies exposure. Lack of access to hydration, shelter, or transportation compounds this risk. During extreme heat days, the city coordinates with Riverside County Emergency Management to activate emergency cooling centers and deploy homeless outreach teams.

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4.2.2 Drought
Overall Vulnerability and Impact
Cathedral City is highly vulnerable to drought due to its geographic position in the Colorado Subunit of the Sonoran Desert and its reliance on groundwater from the Indio Subbasin, as well as imported water to replenish the Indio Subbasin from the Colorado River via the Colorado River Aqueduct and the State Water Project (through a transfer agreement with Metropolitan Water District). The city receives an average of approximately 4.1 inches of annual rainfall, most of which occurs between November and March. This limited local precipitation makes Cathedral City dependent on external water supplies and long-term groundwater storage.

Climate change is expected to exacerbate drought conditions by increasing average annual temperatures by 4.4°F to 5.8°F by mid-century and reducing snowpack in the Sierra Nevada and Upper Colorado River Basin, both of which feed critical water sources for Southern California. Diminished snowmelt and extended dry seasons will strain water allocations to the Coachella Valley Water District (CVWD) and Desert Water Agency (DWA), Cathedral City’s primary water purveyors.

Drought impacts extend beyond water scarcity. Less efficient groundwater recharge due to higher evapotranspiration rates threatens long-term water sustainability. Prolonged dry conditions increase dust and fine particulate pollution, contributing to respiratory illness and degraded air quality. The risk of wildfires in surrounding foothill areas is also heightened, and water-intensive landscaping losses exacerbate urban heat island effects.

Population
All 51 census tracts in Cathedral City are exposed to drought-related impacts, though effects vary by income level, housing condition, and access to cooling or supplemental water sources. Populations living in older mobile homes or multi-family units-common in areas like the Cathedral Canyon Drive corridor-are more likely to face dehydration, utility shut-offs, and secondary heat impacts.

Critical Facilities
Drought does not structurally damage critical infrastructure, but it does create operational vulnerabilities. Water treatment facilities, fire suppression systems, and emergency medical facilities are dependent on consistent and pressurized water delivery. In drought years, reduced groundwater Local Hazard Mitigation Plan Update
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recharge from the Whitewater Replenishment Facility affects CVWD’s ability to maintain stable aquifer levels.

Fire suppression capabilities-particularly in wildland-urban interface zones near Cathedral Canyon Wash and the southern edges of the Cove neighborhood-are at risk if water pressure drops or storage levels decline. Additionally, prolonged drought may increase electricity demand for water pumping and treatment, straining both energy and water infrastructure simultaneously.

Non-Critical Facilities
Commercial and residential water consumers-including apartment complexes, hotels, and golf resortsface mandatory water restrictions during severe drought. Businesses in landscaping, construction, and hospitality report increased operating costs, loss of revenue, and reduced landscape aesthetic appeal.

Drought-tolerant landscaping incentives and tiered water pricing by CVWD and DWA have helped to reduce waste, but some properties have struggled to retrofit or maintain xeriscape transitions.

Residential yards in central Cathedral City, particularly within HOA-managed communities and mobile home parks, are disproportionately affected by visible water stress, increasing evapotranspiration rates and contributing to higher local temperatures.

Environment
Drought significantly impacts the natural environment, reducing water availability for local ecosystems, increasing wildfire risk, and degrading air quality. • Water Availability: The Whitewater River watershed, which supports the Coachella Valley Groundwater Basin, has experienced drought conditions in 80% of weeks since 2000, with 17% of those weeks classified as Extreme or Exceptional Drought (U.S. Drought Monitor, 2024). • Wildfire Risk: While Cathedral City is not within a designated Very High Fire Hazard Severity Zone, nearby mountain slopes (Santa Rosa and San Jacinto ranges) experience elevated wildfire risk during dry seasons. Blown embers from fires in these areas can threaten neighborhoods at the urban edge.
• Air Quality: Prolonged drought increases fugitive dust emissions and PM10 concentrations, particularly along unpaved lots, construction zones, and riverbeds such as the Whitewater Channel. This contributes to elevated AQI levels and frequent air quality alerts during the spring and fall.
• Urban Tree Canopy: Ongoing drought reduces urban tree health, especially in public medians, parkways, and the Civic Center complex, leading to increased canopy loss and reduced cooling Local Hazard Mitigation Plan Update
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benefits. Tree mortality from drought and bark beetle infestation has also been observed in community parks and older neighborhoods.

Changes in Development Since Last Approved Plan
Development Trends: New residential subdivisions and commercial centers have been constructed since the last LHMP update, increasing total water demand. However, water-efficient appliances and drought-tolerant landscaping requirements in new construction-per CVWD’s Water Efficient Landscape Ordinance-have mitigated per capita use.

Land Use and Zoning: While the city has not enacted major zoning amendments directly targeting drought vulnerability, landscape ordinances and conservation regulations adopted by CVWD and DWA are enforced within city limits. These include turf reduction mandates and recycled water incentives.

Population Shifts: Although the city’s total population has remained stable, there is an increasing share of residents aged 65 and over (18.4%), who are more susceptible to dehydration and fixed-income utility burden.

Impacts on Vulnerable Populations
Low-Income Residents: Residents in cost-burdened households may be unable to afford rising water rates or fines for overuse. They are less likely to own high-efficiency appliances or have access to subsidized drought retrofit programs. These impacts are most concentrated in the city’s central and eastern census tracts, based on ACS 2022 and CVWD affordability thresholds.

Elderly Individuals: Seniors are more likely to suffer heat-related illnesses exacerbated by limited water access, especially during billing moratoriums or water shut-offs. Older residents also have limited mobility, which may hinder access to water distribution or assistance sites during supply interruptions.

People with Disabilities: Individuals requiring dialysis, cooling systems, or humidifiers are particularly vulnerable to drought-related utility disruptions. Accessibility barriers further limit their ability to obtain emergency water or seek medical help during compounded events (e.g., drought and heatwave).

Outdoor Workers: Construction, landscaping, and agricultural workers are heavily affected during Stage 2 and Stage 3 drought restrictions, which limit outdoor water use and raise occupational heat Local Hazard Mitigation Plan Update
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risks. Many of these workers are based in Cathedral City’s industrial zones along Perez Road, Edom Hill, and the West Cathedral Canyon area.

Unhoused Individuals: The city's unhoused residents have very limited access to clean water for hydration, hygiene, and cooling. During summer drought periods, public restrooms and hydration stations become critical for survival. This group remains one of the most at risk and is targeted for support by the Cathedral City Homeless Outreach and Housing Team (HOHT) in coordination with Riverside County Health Services.

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4.2.3 Fire (Urban and Wildfire)
Overall Vulnerability and Impact
Cathedral City faces compound fire risks from both urban and regional wildfire hazards. Although the city itself is not currently within a Cal Fire-designated Very High Fire Hazard Severity Zone (VHFHSZ) per the 2022–2025 updated maps, it remains vulnerable to indirect wildfire impacts from the nearby Santa Rosa and San Jacinto Mountains. Wildfires in these areas-such as those that have affected the Palm Springs Aerial Tramway region or Highway 74 corridors-pose risks through smoke transport, degraded air quality, and ember ignition carried by Santa Ana winds.

Climate change is expected to exacerbate fire risk by extending the duration and intensity of fire seasons. More frequent heatwaves and prolonged drought conditions will continue to dry out vegetation and create favorable conditions for ignition. Santa Ana winds, which blow through the San Gorgonio Pass into the Coachella Valley, can rapidly transport embers into urban areas, increasing ignition risk along the western and southern edges of the city, particularly near the Cove neighborhood, Cathedral Canyon Wash, and landscaped commercial zones near East Palm Canyon Drive.

Urban fire hazards are primarily concentrated in Cathedral City’s aging commercial and residential sectors, where older buildings-particularly those with outdated electrical infrastructure or no internal sprinkler systems-remain vulnerable to rapid fire spread. Industrial corridors along Perez Road, Ramon Road, and Date Palm Drive house auto repair shops, fuel storage areas, and light manufacturing uses that include combustibles or flammable materials, contributing to localized ignition potential. Mobile home parks-such as those east of Landau Boulevard, Vista Chino, and Dinah Shore Drive-face elevated risk due to building materials, density, and limited evacuation access.

Population
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The entire population of Cathedral City is potentially exposed to fire hazards, though levels of vulnerability vary significantly by location, structural conditions, and socioeconomic factors. Mobile home residents, individuals in high-density multi-family developments, and residents near commercial corridors face heightened exposure.

Critical Facilities
Fire incidents that disrupt or damage critical infrastructure pose a substantial threat to citywide resilience. Cathedral City operates three fire stations:
• Fire Station 411 (36913 Date Palm Drive)
• Fire Station 412 (32100 Desert Vista Road)
• Fire Station 413 (27610 Landau Boulevard)
These stations serve not only the city but participate in mutual aid agreements across Riverside County.

Medical facilities such as urgent care centers and long-term care homes, particularly along Gerald Ford Drive, depend on reliable HVAC and filtration systems to safeguard at-risk populations during wildfire smoke events.

Electrical substations and transformers maintained by Southern California Edison (SCE) near Edom Hill and along Vista Chino are critical to maintaining energy resilience. Fire-induced failures at these locations could result in widespread outages. Additionally, Cathedral City's portion of the CVWD and Desert Water Agency (DWA) systems must be maintained during fire events to support water pressure for firefighting. Pump stations, particularly near Dinah Shore Drive and Canyon Plaza, are at risk of thermal or smoke-related mechanical failure during extended fire events.

Non-Critical Facilities
Cathedral City’s logistics and retail sectors, particularly along Ramon Road, East Palm Canyon Drive, and the Perez Road industrial corridor, include numerous facilities with high ignition potential and combustible stockpiles. These areas could experience significant economic losses in the event of an industrial fire. Fire propagation through older commercial centers-many of which pre-date modern fire code requirements-could lead to multi-structure events.

Educational institutions like Cathedral City High School, located in the north-central portion of the city, are also susceptible to wildfire smoke infiltration and may be forced to close if indoor air quality Local Hazard Mitigation Plan Update
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declines during regional fire events. Disruption to school operations affects working families and vulnerable student populations, many of whom rely on schools for daily meals and health support.

Environment
Urban and regional fire hazards in Cathedral City can result in direct and cascading environmental consequences:
• Air Quality Impacts: Cathedral City already experiences frequent poor air quality days during the fall wildfire season. AQMD data indicates the region regularly exceeds National Ambient Air Quality Standards (NAAQS) for PM2.5 and ozone during large regional fires. • Water Contamination: Chemical and oil runoff from vehicle service shops or paint storage facilities in the industrial districts can pollute the Cathedral Canyon Wash, especially when mixed with fire suppression foam or damaged sprinkler systems. • Vegetation Loss: City-maintained street trees and small parklands-particularly in Town Square Park and Panorama Park-may be lost to localized structure fires or ember ignition, further degrading urban cooling services.
• Ember Transport Risk: Areas along Eagle Canyon Dam, Varner Road, and the city’s southern boundary are particularly exposed to wind-borne embers from wildfires in the foothills, including mudflow-prone canyons.

Changes in Development Since Last Approved Plan
Development Trends: Since the last LHMP, Cathedral City has experienced continued growth in both residential and commercial sectors. While recent developments comply with the latest California Building and Fire Codes-including ignition-resistant materials and defensible space requirementslegacy developments continue to account for a majority of the city’s structure fires.

Land Use and Zoning: While fire-resistant requirements are in place in zoning and building regulations, no significant rezoning or annexations have shifted the city’s exposure to fire risk. However, increased warehouse and mixed-use development within the North City Specific Plan and East Palm Canyon corridor has added potential structural and economic vulnerability.

Population Trends: The city’s aging population-over 18.4% age 65 and older, according to the 2022 ACS-represents an increased demand on evacuation and sheltering services during fire or smoke emergencies.

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Impacts on Vulnerable Populations
Low-Income Residents: Many lower-income residents live in housing without central HVAC or filtration. With limited renters insurance and no disaster savings, they face prolonged displacement or loss following a fire.

Elderly Individuals: Seniors, especially those in isolated homes or senior housing without elevators, may be unable to evacuate during fast-moving fire events. Their pre-existing health conditions also place them at risk from smoke-related illnesses.

People with Disabilities: Accessible transport, mobility support, and power-dependent medical devices are all critical during fire evacuations. These individuals may require registry-based support and medically equipped shelters.

Outdoor Workers: Fire-related air quality degradation affects construction, delivery, and public works crews. OSHA-compliant protective gear and adjusted work schedules are essential to prevent heat and smoke exposure.

Unhoused Individuals: Many unhoused persons reside along drainage channels or near commercial plazas. Without access to clean indoor air or transportation, they are at high risk during both urban and regional fire events.
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4.2.4 Power Outage
Overall Vulnerability and Impact
Cathedral City is vulnerable to power outages resulting from multiple hazard types, including extreme heat, high winds, wildfires, and earthquakes. These outages may be brief or prolonged, depending on the disruption's severity and cause. Southern California Edison (SCE) maintains Cathedral City’s electric service infrastructure and, in high-risk fire weather, may implement Public Safety Power Shutoffs (PSPS) to reduce ignition hazards, especially during Santa Ana wind events. Although PSPS events have more frequently affected unincorporated and mountainous areas of Riverside County, their cascading effects-including cellular outages and traffic signal disruptions-can extend into Cathedral City.

The city's electrical infrastructure includes major transmission lines along Date Palm Drive, Landau Boulevard, and Dinah Shore Drive, with several substations serving residential and commercial zones.

Power outages, particularly during high-demand periods in summer, have potential to impact medical services, cooling capacity, traffic operations, and emergency communication.

Climate change is intensifying these risks. Elevated temperatures increase demand for cooling, putting additional strain on the regional grid. Prolonged outages can disrupt not only routine services but also emergency response capacity, particularly for individuals reliant on electrically powered medical devices and refrigeration for essential medications. During Tropical Storm Hilary in August 2023, for example, a regional fiber line was severed, disrupting 911 communications throughout the Coachella Valley. Cathedral City was forced to reroute emergency calls to non-emergency business lines, underscoring the vulnerability of critical communications infrastructure.

Population
The entire population of Cathedral City is exposed to potential power outages, but those in heat-prone housing, medically vulnerable households, and residents lacking backup systems are at elevated risk.

Power outages impact refrigerated food storage, communication systems, and access to transportation, disproportionately affecting those without backup power options. Growing adoption of electric vehicles, especially in newer developments, may further constrain mobility during widespread outages if charging infrastructure is compromised.

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Critical Facilities
Power outages pose serious risks to critical infrastructure, including Cathedral City Fire Stations 411, 412, and 413, police facilities, water and wastewater treatment systems, and public health institutions.

Most of these facilities are equipped with backup generators, but sustained outages may exhaust fuel reserves or strain equipment.

Water and wastewater systems managed by CVWD and DWA rely on electric pumps and telemetry controls. Outages can lead to drops in water pressure, limiting firefighting capacity and increasing contamination risk. Additionally, traffic signals and emergency communication networks may lose function without adequate backup systems, impeding incident response and evacuation efforts.

Non-Critical Facilities
Businesses across Cathedral City, including retail centers along East Palm Canyon Drive and Ramon Road, industrial operations on Perez Road, and logistics facilities, are vulnerable to outages. Economic losses from halted operations, spoilage, and supply chain disruptions can be significant, particularly for temperature-sensitive sectors such as food service and warehousing.

Schools and community centers-especially those serving as designated cooling shelters-may be forced to close if outages occur during extreme heat. This disrupts educational continuity and reduces access to safe indoor environments during climate emergencies.

Residential impacts are most severe among households that lack access to generators or battery storage.

Loss of internet and cellular service may isolate residents from emergency information, while food spoilage and loss of HVAC systems can endanger health and safety, especially during summer heatwaves.

Environment
While outages do not directly damage natural environments, indirect impacts can include:
• Air Pollution: Generator use increases emissions of carbon monoxide and particulate matter.

Extended use during outages-especially in industrial zones-can degrade air quality. • Hazardous Spills: Facilities using automated containment or refrigeration systems may experience chemical releases or leaks if these systems fail.

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• Water Quality Risk: Interruptions in wastewater pumping or treatment can increase the likelihood of untreated discharges into the Cathedral Canyon Wash or other local drainage systems.

Changes in Development Since Last Approved Plan
Development Trends: Cathedral City has seen ongoing industrial and commercial growth, increasing demand on the regional power grid, especially in newer industrial parks and the North City Specific Plan area.

Land Use and Zoning: No zoning changes have significantly altered the city’s exposure to power outage risks. However, increasing density and reliance on electric vehicles and HVAC systems heighten overall system dependency.

Population Shifts: While overall population growth has been slow, the proportion of residents over age 65 has increased to 18.4% as of the 2022 ACS. This demographic trend heightens the importance of energy resilience in residential facilities and healthcare centers.

Impacts on Vulnerable Populations
Low-Income Residents: These households may lack access to alternative energy sources such as generators or battery-powered fans, leading to increased exposure during outages. Limited resources also mean they are more likely to experience food insecurity following refrigerator failure.

Elderly Individuals: Many older adults rely on air conditioning, oxygen concentrators, or refrigerated medications. Outages may significantly impair their ability to remain safely at home, particularly if communication systems are also disrupted.

People with Disabilities: For individuals who use powered mobility aids, ventilators, or home dialysis machines, electricity loss is potentially life-threatening. Backup power and accessible transport are essential for emergency preparedness.

Unhoused Individuals: Many rely on public facilities for access to electricity, water, and shelter. If libraries, cooling centers, or shelters lose power, access to safe indoor environments is lost.

Non-English-Speaking Populations: Without multilingual alerts and culturally tailored outreach, these residents may not be aware of power outage protocols or cooling center locations, limiting their ability to respond effectively.

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4.2.5 Earthquake
Overall Vulnerability and Impact
Cathedral City is highly vulnerable to earthquakes due to its proximity to major active fault systems, including the San Andreas Fault, Banning Fault, Garnet Hill Fault, and San Jacinto Fault Zone. The San Andreas Fault, which runs northeast of the city along the Indio Hills Fault section, represents the greatest seismic threat and is capable of generating earthquakes exceeding magnitude 8.0. The Banning Fault, an active strand of the San Andreas system, is capable of producing magnitude 7.4 earthquakes with peak ground accelerations ranging between 0.45g and 0.9g, which could severely impact structures and infrastructure throughout the city.

Ground shaking remains the most significant threat; however, liquefaction, surface rupture, lateral spreading, and utility disruptions also pose serious risks. Liquefaction potential is highest in the northern areas of Cathedral City where water tables are shallower and soils are more susceptible, particularly near the Whitewater River and adjacent to the San Andreas Fault zone. Seismically induced settlement and ground deformation are also risks in areas underlain by unconsolidated alluvial sediments, common in central and northern portions of the city.

An earthquake could cause major disruptions to the city’s economic activities, particularly in industrial corridors like Perez Road, and could damage key transportation assets such as Interstate 10 and regional arterial roads. Widespread infrastructure damage, including to electricity, gas, and water systems, could compound emergency response difficulties.

Population
The entire population of Cathedral City is at risk from earthquake-related impacts. Residents living in unreinforced masonry buildings, older mobile homes, or non-retrofitted structures are especially vulnerable. People reliant on utilities for medical care or mobility are disproportionately affected by service interruptions following seismic events.

Critical Facilities
Critical facilities-such as the Emergency Operations Center, police and fire stations, and healthcare providers-must remain functional during and after an earthquake. Fire Stations 411, 412, and 413 must be able to coordinate search-and-rescue, fire suppression, and emergency medical response operations.

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If these facilities sustain structural or system damage, Cathedral City’s emergency response capabilities would be significantly compromised.

Water and sewer systems operated by CVWD and DWA may be affected by ruptured pipelines and failed pumping stations. Transportation routes such as Date Palm Drive, Ramon Road, and Dinah Shore Drive may become impassable due to bridge damage or road collapse. Gas lines could rupture and cause fires in residential neighborhoods.

Non-Critical Facilities
Non-critical facilities-such as schools, houses of worship, commercial centers, and industrial warehouses-are still vulnerable to seismic damage. Buildings constructed prior to the 1980s without retrofitting may collapse or suffer major structural compromise. Commercial losses from supply chain interruptions and property damage could be extensive, particularly in auto sales, logistics, and light manufacturing.

Residential units, including multi-family housing and older mobile home parks, are at risk of collapse or loss of habitability. Displacement pressures would strain the city’s emergency shelter capacity, particularly in areas like the Cathedral Canyon Cove neighborhood, which includes older housing stock.

Environment
Earthquakes can cause landslides in the Santa Rosa Mountains and Indio Hills, threatening residential developments near the base of these slopes. Ground rupture, subsidence, and slope instability may result in utility corridor failures or closed roads.

Chemical leaks or hazardous spills from industrial areas along Perez Road or within the North City Specific Plan area could contaminate soil and groundwater. Earthquakes may also damage stormwater infrastructure, increasing the risk of localized flooding or stormwater pollution.

Changes in Development Since Last Approved Plan
Development Trends: New construction is required to meet seismic code standards; however, retrofitting of pre-code buildings remains incomplete in parts of the city.

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Land Use and Zoning: No significant changes in land use policy have occurred that alter citywide earthquake vulnerability.

Population Shifts: The percentage of residents over 65 has increased since the previous plan, necessitating additional planning for medical, mobility, and communication needs during postearthquake recovery.

Impacts on Vulnerable Populations
Low-Income Residents: Recovery from earthquake damage may be delayed due to a lack of financial resources and access to insurance.

Elderly Individuals: Many seniors may require mobility assistance or power-dependent medical devices, heightening vulnerability during outages or evacuations.

People with Disabilities: Structural damage, inaccessible shelters, and disrupted support services can create major barriers for individuals with disabilities.

Unhoused Individuals: Earthquake response systems must account for unhoused residents, many of whom live in unsafe or informal shelters.

Non-English-Speaking Populations: Linguistic isolation may prevent access to emergency notifications and assistance. Multilingual communications are essential for effective response and recovery.

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4.2.6 Flooding
Overall Vulnerability and Impact

Cathedral City is vulnerable to flooding from multiple sources, including heavy rainfall, stormwater runoff, and infrastructure failures. Localized flooding occurs due to inadequate drainage, urban development, and extreme weather events. Approximately 14.2% of properties in Cathedral City are at risk of flooding over the next 30 years.

The region’s arid climate typically results in long dry periods, punctuated by intense storm events, particularly during winter and late summer monsoon season. Cathedral City’s urban landscape, with extensive industrial and commercial development, exacerbates flood risk due to impervious surfaces that hinder natural water absorption. The Whitewater River Channel serves as the primary drainage facility for the city, conveying stormwater flows from multiple tributaries, including Cathedral Canyon Wash and East Cathedral Canyon Wash.

Secondary impacts of flooding include damage to transportation networks, disruptions to utilities, and increased mold risks, structural instability, and economic losses. Flash flooding is particularly concerning in areas with outdated or undersized stormwater infrastructure, including Gerald Ford Drive, Dinah Shore Drive, and the Date Palm Drive corridor, which have historically experienced closures due to floodwaters or debris flow.

Population
The entire population of Cathedral City is exposed to potential flooding, though the level of impact varies based on location, housing conditions, and socioeconomic factors. Residential areas near major storm drain channels, such as the Whitewater River, West and East Cathedral Canyon Washes, and Eagle Canyon Wash, face elevated risks. Floodwaters pose direct hazards, including drowning, electrocution, and exposure to contaminated water.

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Critical Facilities
Critical facilities such as emergency response centers and utility infrastructure must remain operational during flood events to ensure public safety. Facilities with underground utility connections are vulnerable to water intrusion, which can cause equipment failure and extended service disruptions. Power substations and energy infrastructure-such as those near Vista Chino, Landau Boulevard, and Varner Road-may also be at risk of short circuits or outages from flood damage.

The Whitewater River drainage system carries stormwater from a 720-square-mile watershed, generating peak flows of 47,000 cubic feet per second (cfs) during a 100-year storm. The Coachella Valley Water District (CVWD) and Riverside County Flood Control and Water Conservation District (RCFCD) manage regional stormwater infrastructure to mitigate regional flooding risks. The city also coordinates with the Coachella Valley Association of Governments (CVAG) on roadway flood risk mitigation, including active projects along Varner Road and Date Palm Drive to improve stormwater capacity and reduce 100-year flood hazards.

Non-Critical Facilities
Non-critical facilities, such as schools, businesses, and industrial operations, may experience structural damage, utility failures, and operational disruptions during flood events. Commercial districts with large impervious surfaces-including East Palm Canyon Drive and Perez Road-are particularly susceptible to ponding and runoff issues. Industrial facilities are vulnerable to hazardous material spills if floodwaters interact with chemical storage or mechanical operations.

Environment
Flooding can have significant environmental consequences, including erosion, sedimentation, and water contamination. Industrial zones in Cathedral City contain facilities that store hazardous materials, increasing the risk of contamination during flood events. Key environmental concerns include:
• Water Contamination: Flood events may overwhelm drainage systems, leading to water quality issues as runoff carries debris, oil, and chemicals into storm drains and waterways. • Soil Erosion and Sedimentation: Unstable slopes and developed areas with insufficient drainage may experience erosion, affecting natural habitats and infrastructure. This is especially relevant Local Hazard Mitigation Plan Update
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near the Santa Rosa Mountains foothills, where stormwater from upstream burn scars can accelerate debris flow, as occurred during Tropical Storm Hilary (2023). • Impact on Vegetation: Flooding can damage urban landscaping and reduce the effectiveness of stormwater control measures like green infrastructure and bioswales, particularly in newly developed or landscaped areas.

Localized feedback from residents highlights flood-prone areas where nature-based approaches—such as wetland restoration—may offer viable mitigation solutions. These areas merit further study for suitability as multi-benefit flood control sites that align with ecological and community goals, as demonstrated by successful models in Tempe and Tucson.

Changes in Development Since Last Approved Plan
Development Trends: Since the last hazard mitigation plan, Cathedral City has continued to expand commercial and industrial areas, especially north of Interstate 10 and along Palm Drive and Varner Road, increasing impervious surfaces and stormwater runoff.

Land Use and Zoning: No major zoning changes have significantly altered flood risk, though updates to the city’s Comprehensive Storm Drain Master Plan are in progress to address vulnerabilities.

Population Shifts: While overall population growth has been moderate, an increasing number of older adults and medically vulnerable individuals may require additional support during flood events.

Impacts on Vulnerable Populations
Low-Income Residents: Households with limited financial resources may struggle to recover from flood-related damages, particularly if they lack flood insurance. Temporary displacement due to flooding can create additional economic hardships, including lost wages and increased transportation costs
Elderly Individuals: Older adults may experience difficulties evacuating flood-prone areas, particularly those with mobility limitations. Flood-related power outages can also impact those reliant on electrically powered medical devices.

People with Disabilities: Individuals with disabilities may face heightened risks during flood events due to evacuation barriers, reliance on accessible transportation, and potential disruption of medical services.

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Unhoused Individuals: The unhoused population is critically vulnerable, as they often lack access to safe shelter, clean water, and emergency services. Flooding increases exposure to unsanitary conditions, heightening the risk of disease.

Non-English-Speaking Populations: Language barriers may prevent some residents from receiving timely flood warnings and evacuation instructions, increasing their risk of harm. Targeted outreach and multilingual emergency communications are essential to address these challenges. (this page intentionally left blank)
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4.2.7 High Wind/Storms
Overall Vulnerability and Impact
Cathedral City is vulnerable to high wind events, particularly Santa Ana winds, which are strong, dry, downslope winds that occur most frequently between October and February. These winds can exceed speeds of 50 to 70 mph and are known to intensify wildfire risks, cause structural damage, and increase airborne dust, reducing air quality. Winter storms and occasional strong convective thunderstorms can also bring high winds, heavy rain, and localized flooding, but the city is not historically impacted by hurricanes or tornadoes. While Cathedral City itself is not designated in a Cal OES high wind hazard zone, the surrounding Coachella Valley is regularly impacted by wind-driven dust storms, especially along corridors such as Varner Road, Interstate 10, and Palm Drive, exacerbating respiratory issues and visibility hazards.

Wind speeds in Cathedral City are typically highest in the northern portions of the city near the foothills and open desert terrain, where gusts exceeding 50 mph have been recorded. Areas such as Varner Road, Mountain View Road, and neighborhoods adjacent to Interstate 10 are particularly exposed. Unsecured structures, construction materials, and lightweight buildings are especially susceptible to wind damage, and power outages are common during strong wind events, sometimes compounded by Public Safety Power Shutoffs (PSPS).

Population
The entire population of Cathedral City is exposed to the hazards associated with high winds and storms. Residents in older homes, mobile home parks (including those along Perez Road, Cathedral Canyon Drive, and East Palm Canyon Drive), and non-retrofitted structures are particularly at risk, as these buildings may not be constructed to current wind-load standards. Airborne dust and debris from windstorms can exacerbate health conditions, particularly for vulnerable populations with respiratory illnesses such as asthma and COPD.

Critical Facilities
Critical facilities such as emergency response centers, fire stations, water treatment plants, and power substations must remain operational during high wind and storm events. Downed power lines, windborne debris, and dust intrusion can disrupt essential services. High winds can also damage cell towers and broadband infrastructure, impeding emergency communication capabilities.

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Water treatment and wastewater facilities may experience service disruptions if power is lost or if windblown debris clogs stormwater drainage systems. The risk of ignition from arcing or downed lines is a major concern during Santa Ana wind events, especially in combination with dry vegetation in areas such as Cathedral Canyon Wash and near Flat Top Mountain.

Non-Critical Facilities
Schools, businesses, and industrial properties can experience significant damage during high wind events. Schools may temporarily close due to safety concerns or transportation service disruptions.

Commercial and industrial facilities, especially along Perez Road, Date Palm Drive, and in north Cathedral City’s light industrial zones, may suffer economic losses from inventory damage, structural impacts, or halted operations.

Mobile homes, temporary structures, and older buildings with inadequate anchoring or roof bracing are at increased risk. Poorly maintained trees or palm fronds, especially in medians and residential areas, may fall and cause property damage or obstruct roads.

Environment
High wind and storm events can have significant environmental consequences, affecting vegetation, air quality, and stormwater management systems.
• Urban Forestry and Vegetation Damage: Strong winds can uproot trees, break limbs, and damage landscaping in parks, street medians, and residential neighborhoods. Tree failure is especially common among non-native ornamental species.
• Airborne Dust and Pollutants: Santa Ana winds are known to carry high levels of PM10 and PM2.5, degrading air quality and triggering air quality warnings. This is especially acute near blowsand-prone areas such as Varner Road, Palm Drive, and the city’s northwestern edge. • Stormwater Runoff and Pollution: Windstorms that coincide with rainfall events can carry significant dust, sediment, and surface contaminants into storm drains, impacting the Whitewater River Channel and Cathedral Canyon Wash.
• Wildfire Risk: High winds rapidly spread embers and flames, especially during dry conditions.

Although Cathedral City is not heavily vegetated, structures near open land or desert terrainsuch as along Edom Hill or the western city boundary-remain vulnerable to wind-driven ember ignitions.

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Changes in Development Since Last Approved Plan
Development Trends: Cathedral City has continued to develop commercial and industrial properties, particularly north of Interstate 10. These areas face higher wind exposure due to open terrain and increased structure count. All new development is required to meet California Building Code (CBC) wind resistance standards.

Land Use and Zoning: There have been no major zoning changes that significantly alter the city’s exposure to high winds and storms.

Population Shifts: While the city’s total population has remained relatively stable, the percentage of residents over age 65 has increased, elevating health vulnerability to storm-related disruptions such as power loss and poor air quality.

Impacts on Vulnerable Populations
Low-Income Residents: Households with limited financial resources may struggle to afford repairs after wind damage or replace spoiled food during power outages.

Elderly Individuals: Older adults may have difficulty evacuating during extreme weather events, particularly if transportation routes are blocked by debris. Prolonged power outages can also increase health risks for elderly residents reliant on medical equipment.

People with Disabilities: Individuals who rely on electrically powered medical devices, accessible transportation, or in-home care services may face significant health risks if storms cause power outages or transportation disruptions.

Unhoused Individuals: The unhoused population is particularly vulnerable to high wind and storm events, as they often lack access to secure shelter and emergency services. Strong winds can destroy makeshift encampments and increase the likelihood of injuries.

Non-English-Speaking Populations: Language barriers may limit access to emergency alerts and preparedness resources, increasing the risk of delayed response and lack of awareness about storm risks.

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4.2.8 Cyberattack/IT Disruption
Overall Vulnerability and Impact
Cathedral City, like many urban communities, is increasingly vulnerable to cyberattacks and IT disruptions due to its reliance on digital infrastructure to support government operations, emergency services, public utilities, and business activities. A cyberattack can take many forms, including ransomware, data breaches, distributed denial-of-service (DDoS) attacks, and attacks targeting industrial control systems that manage utilities and transportation networks.

Cyber threats have grown in complexity and frequency, with local governments, financial institutions, healthcare providers, and critical infrastructure operators facing heightened risks. A significant cyberattack could compromise sensitive data, disrupt essential services, and cause economic and reputational harm to the city. Public sector entities, including law enforcement and emergency response agencies, rely on interconnected digital systems, making them susceptible to coordinated attacks that target 911 dispatch systems, public records databases, and real-time traffic management. Power outages, water supply interruptions, and communication failures resulting from a cyberattack could have cascading effects, especially during extreme weather events or other concurrent hazards.

Notably, during Tropical Storm Hilary in August 2023, a regional fiber line failure caused a 911 service disruption in Cathedral City, which required emergency calls to be rerouted to administrative lineshighlighting the fragility of critical communications infrastructure during compounding hazards.

Population
The entire population of Cathedral City is exposed to cyberattack risks, particularly as residents and businesses rely on digital communication, financial services, and emergency response systems. The impacts of an IT disruption vary based on the severity and duration of the event. A prolonged outage affecting municipal services could prevent residents from accessing critical information, paying bills, or requesting emergency assistance.

Critical Facilities
Cyberattacks targeting critical facilities can have widespread and severe consequences. Emergency response operations, hospitals, water treatment plants, and power infrastructure rely on digital control systems to maintain functionality and security. A cyberattack could disrupt:

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• 911 and emergency response systems, delaying dispatch services for law enforcement, fire departments, and paramedics.
• Hospital networks, impacting patient records, emergency room operations, and medical equipment reliant on IT infrastructure.
• Water and wastewater treatment facilities, where cyber interference with industrial control systems could lead to contamination, pressure loss, or service failures. Facilities managed by CVWD and DWA are especially critical.
• Electric grid operations, where cyberattacks on smart grid technology or substations operated by Southern California Edison could result in blackouts or power surges, affecting businesses and residences.

Non-Critical Facilities
Non-critical facilities, including businesses, schools, and community centers, are highly dependent on IT infrastructure for daily operations. A cyberattack disrupting internet access, payment processing, or communication networks could significantly impact economic activity and public services.

Retail businesses and financial institutions could experience financial losses if point-of-sale systems, ATMs, or online banking services are disrupted. Manufacturing and logistics operations in Cathedral City-particularly in the Perez Road and north-of-I-10 industrial corridors-which depend on automated systems and real-time inventory tracking, may face significant delays and revenue losses in the event of an IT disruption.

Schools rely on digital learning platforms and online administrative systems, meaning a cyberattack could interrupt education, limit access to student records, and compromise data privacy. Government offices that manage public records, business licenses, and utility billing systems could also face operational challenges during an IT disruption.

Environment
Cyberattacks do not directly cause environmental damage, but they can lead to secondary hazards that impact air and water quality, hazardous material containment, and urban sustainability initiatives. A cyberattack targeting industrial facilities or chemical plants could disable safety monitoring systems, increasing the risk of accidental hazardous material spills or chemical releases. If an attack disrupts water treatment operations, contamination events could occur, posing risks to public health and natural ecosystems-particularly near Cathedral Canyon Wash, the Whitewater River Channel, or areas with underground chemical storage.

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Changes in Development Since Last Approved Plan
Development Trends: Since the last approved hazard mitigation plan, Cathedral City has seen increased digital integration in municipal operations, transportation systems, and public utilities.

Land Use and Zoning: There have been no significant land use changes directly affecting cyberattack vulnerability.

Population Shifts: While the overall population has remained stable, increased remote work and digital dependency have made residents more vulnerable to cyberattacks targeting personal devices, financial institutions, and online government services.

Impacts on Vulnerable Populations
Low-Income Residents: Cyberattacks targeting financial institutions, municipal services, or identity records can disproportionately affect low-income individuals, who may lack resources to recover from financial fraud, delayed benefit payments, or credit disruptions. Limited access to cybersecurity education may further increase their exposure to phishing scams and online fraud.

Elderly Individuals: Older adults may be more susceptible to identity theft, financial scams, and fraudulent activity resulting from data breaches. A cyberattack disrupting healthcare networks or telehealth platforms used by seniors could also limit access to medical care.

People with Disabilities: Individuals with disabilities who rely on assistive technology, telehealth services, or online transportation scheduling may experience severe disruptions if cyberattacks disable digital accessibility tools. Power outages related to cyberattacks could also impact medical equipment reliant on electricity.

Unhoused Individuals: Many unhoused individuals rely on digital services to access social programs, employment resources, and communication tools. Cyberattacks that disrupt government services or nonprofit organizations could create additional barriers for those seeking assistance.

Non-English-Speaking Populations: Language barriers may limit awareness of cybersecurity threats and response strategies. A cyberattack on emergency alert systems or public information platforms could further reduce access to real-time hazard updates for non-English-speaking residents.

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4.2.9 Infectious Disease/Pandemic
Overall Vulnerability and Impact
Cathedral City is vulnerable to infectious disease outbreaks and pandemics, which can have widespread impacts on public health, the economy, and essential services. The COVID-19 pandemic highlighted the risks associated with global disease transmission, particularly in densely populated urban areas and communities with high levels of industrial and commercial activity.

Infectious diseases can spread through various transmission pathways, including airborne transmission (influenza, COVID-19), vector-borne transmission (West Nile virus, Zika), waterborne contamination (E. coli, norovirus), and direct contact transmission (tuberculosis, hepatitis). The risks associated with infectious disease outbreaks are heightened in locations with high levels of social interaction, such as workplaces, schools, healthcare facilities, and public transportation.

The impacts of an infectious disease outbreak can extend beyond immediate health concerns, affecting economic stability, workforce availability, and public safety. During a pandemic, businesses may experience supply chain disruptions, healthcare systems may become overwhelmed, and public health measures such as quarantines, travel restrictions, and school closures may be necessary. Long-term health consequences, including post-viral complications and increased demand for medical services, can place additional strain on local healthcare infrastructure.

Population
The entire population of Cathedral City is vulnerable to infectious disease outbreaks, though the level of risk varies based on age, health conditions, socioeconomic status, and access to healthcare. Certain populations face heightened risks, including older adults, individuals with preexisting medical conditions, unhoused individuals, and those without access to adequate healthcare.

High-density housing and workplaces, including the city’s industrial and logistics sectors, can facilitate disease transmission due to close-quarters working conditions and shared facilities. Workers in manufacturing, retail, and food service industries are particularly vulnerable due to frequent in-person interactions. Schools and childcare centers also present high transmission risks due to close-contact environments and the difficulty of enforcing social distancing measures.

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A pandemic can have psychological and emotional impacts on residents, increasing stress, anxiety, and social isolation. Mental health effects may persist long after the initial outbreak, requiring expanded behavioral health services and community support programs.

Critical Facilities
Hospitals and urgent care centers serving Cathedral City-most notably Eisenhower Health and regional urgent care clinics-must maintain surge capacity and continuity of operations during infectious disease events. A shortage of healthcare workers, PPE, or critical supplies could impair their ability to treat patients with infectious and non-infectious conditions alike.

Emergency responders from Cathedral City Fire Department and Police Department must operate under elevated health precautions, with reduced staffing or quarantine protocols impacting response capability. Cathedral City successfully implemented modified response models during the COVID-19 emergency to reduce exposures.

Essential utilities such as wastewater systems operated by CVWD or DWA, and energy distribution from Southern California Edison, must also remain functional despite potential staffing shortfalls.

SCADA-managed infrastructure systems are particularly vulnerable during concurrent cybersecurity or staffing crises.

Non-Critical Facilities
Non-critical facilities, including businesses, educational institutions, and recreational centers, can experience significant disruptions during an infectious disease outbreak. Schools may be required to close or transition to remote learning, creating challenges for students, parents, and educators.

Businesses, particularly those in the retail, hospitality, and entertainment industries, may experience revenue losses due to reduced customer demand and workforce shortages.

Environment
Infectious disease outbreaks can have both direct and indirect environmental impacts. The increased use of medical supplies, including personal protective equipment (PPE), can contribute to waste management challenges. Disposal of contaminated materials, such as masks, gloves, and testing kits, must be carefully managed to prevent environmental contamination.

During pandemics, public health measures such as sanitation efforts, disinfection procedures, and air filtration improvements may be implemented to reduce disease spread. While these measures help protect public health, they may also lead to increased energy consumption and chemical runoff from disinfectants entering local waterways.

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Changes in Development Since Last Approved Plan
Development Trends: Since the last hazard mitigation plan, there has been a heightened awareness of the need for pandemic preparedness in urban planning and infrastructure development.

Land Use and Zoning: No major land use changes have directly influenced infectious disease vulnerability.

Population Shifts: While Cathedral City’s overall population has remained stable, demographic trends indicate an increasing number of older adults who may require specialized healthcare services during disease outbreaks.