Calistoga City Council
October 6, 2026

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Figure 2-5: City of Calistoga Dependent Age Groups Map
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Figure 2-6: City of Calistoga Disabled Elderly Map
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Race, Ethnicity & Language
Natural disasters compound racial disparities; non-white individuals and communities receive less recovery aid from FEMA than their white counterparts, even where the amount of damage is the same. (Howell, Junia; Elliott, James R., 2019) (National Advisory Council, 2020) These disparities are evidence of the complicated relationship between disaster recovery and overlapping social vulnerabilities including race, income, language, and health. Black and Latino residents are more likely to be low income and renters, conditions which create barriers to navigating FEMA’s Individual Assistance programs. Communities with more non-white residents may have lower tax revenue and property values, which means less investment in mitigation and rebuilding efforts before and after an emergency.

Figure 2-7 depicts the racial and ethnic composition of the City of Calistoga. According to ACS data, the city is mostly White, but also has a significant Hispanic or Latino population.

Residents with limited English proficiency (LEP) face heightened barriers to understanding emergency alerts, accessing preparedness resources, and navigating post-disaster recovery programs. In Calistoga, approximately 20% of households speak Spanish, but only around 3% report limited English proficiency. (Table 2-7). Figure 2-8 highlights where Spanish-speaking populations are concentrated in Calistoga.

Table 2-7: City of Calistoga Household Languages
Jurisdiction Households (HH) Spanish Speaking %
Limited
English %
Other
Lang. %
Napa County 55,588 8,738 15.7% 2,141 3.9% 12 0.0%
City of American Canyon 5,924 1,069 18.0% 177 3.0% - 0.0% City of Calistoga 2,330 474 20.3% 63 2.7% - 0.0%
City of Napa 31,666 5,800 18.3% 1,653 5.2% 9 0.0%
City of St. Helena 2,963 370 12.5% 88 3.0% - 0.0%
Town of Yountville 1,824 49 2.7% 21 1.2% - 0.0%
Source: ACS 5-Year, 2017-2022
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Figure 2-7: City of Calistoga Race and Ethnicity Map
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Figure 2-8: City of Calistoga Spanish-Speaking Households Map CAL OES SUBMITTAL - JUNE 2026
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Social Vulnerability Index (SVI)
The Centers for Disease Control and Prevention (CDC) Social Vulnerability Index (SVI) for City of Calistoga reveals important spatial and demographic patterns that have direct implications for equitable hazard mitigation planning. As discussed in detail in Volume 1, Section 1.4.3.6, the SVI is a composite measure developed by the CDC to identify communities that are more likely to require support before, during, and after a disaster. It incorporates a range of factors across four key dimensions: socioeconomic status, household composition and disability, minority status and language, and housing type and transportation access. The resulting index score ranges from 0 (lowest vulnerability) to 1 (highest vulnerability).

Figure 2-9 shows that social vulnerability ranges between 0.50 and 0.75 in Calistoga, which is indicative of moderate SVI. Areas with higher SVI values indicate neighborhoods where residents may have reduced capacity to prepare for, respond to, and recover from hazard events due to factors such as lower income, higher proportions of renters, limited access to vehicles, language barriers, or greater concentrations of elderly and disabled individuals. Conversely, areas with lower SVI scores generally reflect populations with greater access to resources and adaptive capacity.

Spatial patterns in the SVI map suggest that higher social vulnerability is concentrated in portions of the central and southern areas of the city, where multiple vulnerability indicators overlap. These areas may experience disproportionate impacts during events such as flooding, extreme heat, earthquakes, or wildfire smoke episodes, particularly if hazards coincide with power outages, transportation disruptions, or prolonged recovery periods. Residents in higher-SVI neighborhoods may also face challenges accessing emergency information, evacuation assistance, sheltering, and post-disaster financial or housing resources.

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Figure 2-9: City of Calistoga CDC Social Vulnerability Index Map CAL OES SUBMITTAL - JUNE 2026
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2.2.3 Economy
The City of Calistoga plays an important economic role within northern Napa County, serving as a local employment center and tourism hub. The local economy is largely centered around visitor-serving commercial uses and wine production. Calistoga’s location at the junction of Highways 29 and 128 makes it a crossroads of sort within the upper Napa Valley.

Retail, restaurants, and visitor-serving commercial uses are primarily concentrated on Lincoln Avenue.

These businesses contribute significantly to local tax revenues and provide jobs for residents of Calistoga and surrounding communities. At the same time, the concentration of economic activity along Lincoln Avenue increases the importance of protecting critical infrastructure, transportation corridors, and utility systems from natural hazards such as flooding, earthquakes, and power outages.

The city’s commercial economy includes neighborhood-serving retail, restaurants, and personal services that support daily needs and contribute to community vitality. These businesses are particularly sensitive to hazard-related disruptions, as temporary closures, infrastructure damage, or reduced access can result in lost income and longer-term economic impacts. Small businesses may have limited capacity to absorb prolonged disruptions, making economic resilience an important consideration in hazard mitigation planning.

A significant portion of Calistoga’s workforce is employed in sectors that involve physical labor or outdoor activity, including agriculture and visitor-serving commercial uses. These workers may face heightened exposure to hazards such as extreme heat, wildfire smoke, and poor air quality. Climate change projections indicating more frequent heat events and longer wildfire seasons have implications for worker safety, productivity, and business continuity within these sectors.

Economic vulnerability is also influenced by income variability and employment stability. Workers in hourly or service-based positions may experience immediate income loss during disaster-related closures or evacuations, which can compound household vulnerability and slow community recovery. Protecting employment centers, maintaining transportation access, and ensuring continuity of utilities and communications are therefore key components of reducing economic disruption from hazard events.

2.2.4 Growth Trends & Future Development
The City of Calistoga has experienced moderate growth since the 1970s, with development patterns shaped by adopted growth management policies, infrastructure capacity, and regional housing demand. Growth in recent decades has occurred primarily through planned residential development and visitor-serving commercial uses. This approach reflects the city’s long-standing emphasis on directing growth toward areas that can be efficiently served by public services and infrastructure while limiting outward expansion into agricultural and environmentally sensitive lands.

Residential growth has been driven largely by infill development within existing neighborhoods. Recent development activity has included a mix of single-family and multi-family housing intended to CAL OES SUBMITTAL - JUNE 2026
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accommodate population growth and meet state-mandated housing requirements. The City’s Housing Element and Annual Progress Reports document continued efforts to increase housing supply while addressing affordability, infrastructure demands, and community character.

Future development in Calistoga is expected to continue focusing on buildout of remaining developable parcels within the Urban Limit Line and Sphere of Influence. Planned growth areas are generally located near existing transportation corridors, utilities, and employment centers, supporting more compact and efficient development patterns. This strategy reduces the need for extensive new infrastructure and helps limit exposure to hazards associated with hillside development, wildfire risk, and access constraints.

Economic development is also anticipated to remain a key component of future growth. Expansion and intensification of industrial and commercial uses, particularly those related to logistics, manufacturing, and the wine industry, are expected to support employment and fiscal stability. At the same time, continued development in low-lying areas and near critical transportation routes underscores the importance of incorporating hazard mitigation and climate adaptation measures into future land use and infrastructure planning.

2.3 Planning Process
The City of Calistoga followed the planning process detailed in Volume 1, Section 2, including participating in the county-wide Hazard Mitigation Planning Team (HMPT) and formulating their own internal planning team to support the broader planning process.

The city’s representatives in the Steering Group led stakeholder and public engagement efforts alongside the Consultant Team, with assistance from the county-wide HMPT and their internal planning team. This engagement process is described in Volume 1. Specifically, for the City of Calistoga, this included postings to the city website and social media, and outreach events, as documented in Appendix B. Examples of Key Stakeholders engaged by Napa County on behalf of the city with relevance to the development of Calistoga’s mitigation strategy include the USDA and other federal agencies; CAL FIRE and other state agencies; other neighboring jurisdictions; community-based organizations such as the Chamber of Commerce; utility providers like PG&E; UC Davis and other academia; and local businesses.

All Key Stakeholders that were invited to participate in the planning process are listed in Volume 1, Section 2, and the input received from stakeholders was integrated into the city’s annex, as described in Volume 1 Table 2-9. The city’s internal planning team participants, their positions, and how they participated in the planning process are shown in Table 2-8.

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Table 2-8: City of Calistoga Planning Team and Steering Group Members Team Members Title Description of Involvement
Jed Matcham Fire Chief Lead Point-of-Contact, HMPT #1, and #2, BO #1 and #2 Mitch Celaya Interim City Manager Alternate Point-of-Contact, HMPT #4, BO #2 Derek Rayner Public Works Director Participating Stakeholder, BO #1 Greg Desmond Planning and Building
Director
Participating Stakeholder, BO #1
Hamid Heidary Senior Civil Engineer Participating Stakeholder, BO #1 Laura Snideman Former City Manager Participating Stakeholder, BO #1 Jason Tamagni Fire Captain Participating Stakeholder, BO #1 Mark Woods Building Official Participating Stakeholder, BO #1 City of Calistoga participated in a comprehensive hazard mitigation planning process as part of the 2026 Napa County MJHMP update. This included a series of breakout meetings, listed in Table 2-9 that engaged the district’s planning team, which included key city personnel and stakeholders in evaluating hazards, identifying local vulnerabilities, and prioritizing mitigation strategies.

The process began with a County-Wide Steering Group Kickoff Meeting on February 28, 2024. This initial meeting focused on welcoming participants, establishing a shared understanding of the project scope and schedule, clarifying roles and responsibilities of the Steering Group, the county-wide Hazard Mitigation Planning Team (HMPT), and individual jurisdictional planning teams, and included a review of key changes since the 2020 Local Hazard Mitigation Plan The meeting set the foundation for coordinated participation throughout the planning effort.

Throughout the series of breakout meetings, the City of Calistoga engaged in a structured and collaborative planning process focused on assessing hazard risks, identifying vulnerabilities, and developing targeted mitigation strategies. The meetings began with recaps of the county-wide HMPT meetings to ensure alignment of goals and progress.

During the August 22, 2024, breakout out meeting, discussions concentrated on community engagement outcomes, initial risk assessments, and the integration of demographic data to better understand vulnerable populations. Jurisdictional teams reviewed their specific hazard exposures using the Risk Assessment Mapping Platform (RAMP) and participated in prioritization exercises to identify their top hazards.

The November 10, 2025, breakout meeting shifted toward reviewing local capabilities and defining specific areas of concern, which informed the drafting of problem statements. Teams worked collaboratively to refine mitigation alternatives, align actions with FEMA guidelines, and develop a shortlist of priority mitigation actions and inter-jurisdictional collaboration opportunities. Participants also engaged in a hexagon mapping activity designed to visually identify mitigation actions that could benefit from or require CAL OES SUBMITTAL - JUNE 2026
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inter-jurisdictional coordination. These collaborative efforts helped shape a refined set of mitigation alternatives, establish shared planning goals, and align local strategies with FEMA’s Hazard Mitigation Assistance (HMA) funding framework.

The meetings also included consensus-building activities around hazard rankings, capabilities, and planned actions, while providing regular updates on the overall project schedule.

Table 2-9: City of Calistoga Planning Team Meetings
Meeting & Date Agenda / Topics Goals / Key Inputs
County-Wide Steering Group and HMPT Kick-off and Meetings #1 & #2 February 28, 2024– July 18, 2024
Calistoga Planning
Team
Breakout Meeting #1
August 22, 2024
▪ County-wide HMPT meetings #1 and #2 recaps
▪ Community engagement progress and results
▪ Risk assessment and community vulnerability
▪ Demographics and vulnerable populations
▪ Overview of jurisdiction-specific hazard risks and
exposure
▪ Introduction to Risk Assessment Mapping Platform
(RAMP)
▪ Jurisdiction-specific hazard risk ranking exercise
▪ Project schedule updates and next steps
▪ Consensus on jurisdictionspecific priority hazards
▪ Identify capabilities and
potential mitigation actions
▪ Community engagement
volunteers
County-Wide HMPT Meeting #3
March 25, 2025
Calistoga Planning
Team
Breakout Meeting #2
November 10, 2025
▪ Breakout Meeting #1 and HMPT #3 recaps
▪ Review capabilities assessment
▪ Review areas of concern and define problem
statements
▪ Principles of effective mitigation strategies and
actions, and mitigation alternatives
▪ Refine and align jurisdiction-specific mitigation
actions exercise
▪ Project schedule updates and next steps
▪ Consensus on jurisdictionspecific capabilities
▪ Consensus on jurisdictionspecific areas of concern
▪ Consensus on priority
mitigation actions and
collaboration opportunities
▪ Community engagement
volunteers
County-Wide HMPT Meeting #4
December 10, 2025

2.3.1 Public Input & Draft Review
As detailed in Volume 1, Section 2, the draft plan was available for public review and comment from May 15 to June 2, 2026. Public comments received during that time were similar to those gathered throughout the public engagement process, including the need for more equity in the distribution of mitigation activities and funding and the need for enhanced cooperation among jurisdictions, utility providers, and state CAL OES SUBMITTAL - JUNE 2026
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agencies. These comments were incorporated into the city’s mitigation strategy, as appropriate; although, most were already addressed by the Mitigation Action Plan which was based on previous public input.

Public and stakeholder input was gathered and incorporated throughout the plan development process, before the public review period, such as from the online public survey (see Volume 1, Section 2.1.2 and Appendix B, for details). During the review period, jurisdictional staff and stakeholders that participated in the plan development also reviewed the public draft and provided comments on minor corrections and revisions, which were addressed in the final plan.

2.4 What’s New
This section provides an overview of hazard mitigation planning efforts for the planning area and highlights the updates made in the 2026 MJHMP. The City of Calistoga previously participated and maintained a Hazard Mitigation Plan, which guided resilience planning and hazard mitigation actions at the city level.

Calistoga is updating their current plan on a county wide level. This integration reflects the city’s ongoing commitment to regional resilience and acknowledges that many hazards such as flooding, severe storms, and earthquakes cross jurisdictional boundaries.

Through participation in the MJHMP, Calistoga has identified its highest priority hazards, developed hazard specific problem statements, and proposed actionable strategies to reduce risks. By aligning with countywide partners and leveraging regional resources, Calistoga has strengthened its capacity to prepare for, withstand, and recover from disasters while continuing to protect its unique community character.

2.4.1 Mitigation Activities
The city has successfully implemented several initiatives aimed at addressing identified vulnerabilities.

Some of these accomplishments are highlighted in this section and have directly contributed to reducing risks from hazards such as flooding, all hazards, and severe weather. These completed projects showcase Calistoga’s ability to effectively plan, fund, and execute measures that protect its residents and infrastructure.

In addition, Calistoga has systematically reviewed and adjusted its mitigation actions, exemplifying adherence to FEMA’s Planning Policy Guide principles and emphasizing the importance of dynamic and adaptive mitigation planning. By fostering partnerships, leveraging funding opportunities, and prioritizing equity in implementation, the city aligns with best practices to build resilience against natural disasters.

This ongoing effort is a testament to the city's commitment to the principles of risk-informed decisionmaking, equitable resource allocation, and integration with broader regional and state hazard mitigation objectives.

Adjustments to Previous Mitigation Actions
A significant portion of the city's mitigation efforts remain ongoing or in the pipeline. These actions, ranging from infrastructure upgrades to community outreach initiatives, represent the city’s proactive approach to addressing hazards as resources become available.

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Recognizing constraints such as limited funding, staffing, and shifting priorities, the city has reevaluated certain initiatives, leading to their reprioritization or canceling of mitigation actions. Factors such as feasibility, cost-effectiveness, and emerging risks informed these decisions, ensuring alignment with the city’s updated hazard mitigation goals. Adjustments to previous mitigation actions are documented as part of the City of Calistoga’s Mitigation Action Plan Table 2-16, and more specific status updates are provided in Table 2-17.

2.4.2 Mitigation Successes
Calistoga Resiliency Center
The Calistoga Resiliency Center is the world's largest utility-scale, ultra-long duration energy storage project. This first-of-its-kind hybrid hydrogen and battery energy storage system enables a cost-effective, community-scale, clean microgrid that stores and dispatches clean energy, on demand. The microgrid will provide 48 hours of continuous power to Pacific Gas & Electricity Company customers in downtown Calistoga and the surrounding area during a Public Safety Power Shutoffs event.

Hi-Lo Alert System
Recognizing the City of Calistoga susceptibility to wildfires, the Calistoga Fire Department and Calistoga Police Department vehicles are equipped with Hi-Lo Alert Devices that emit a distinctive tone pattern.

Traditional emergency alert systems rely of fixed telecommunication facilities such as cell towers that may be out of service during a wildfire. Hence, Calistoga first responder vehicles have the ability provide mobile evacuation alerts via the Hi Lo Alert System.

Updated Safety Element
The Safety Element update includes multiple mitigation-forward policies such as tailored evacuation messaging for single-access neighborhoods, assessing ingress/egress improvements, zone-based evacuation planning, siting critical infrastructure outside hazard zones where feasible, and maintaining participation in the Napa County MJHMP update cycle.

Water Infrastructure Improvements
The Hazard Mitigation Grant Program (HMGP) has allowed the city to receive seismic retrofits with a new 1- million-gallon water tank. Funding has also been allocated for new SCADA/PLC and generators for treatment plants. The city run Wastewater Treatment Plant also received funding for the New Riverside Pond improvements by removing them from floodplain, as well as lining, repairing creek banks from erosion to protect critical wastewater treatment plant infrastructure.

2.5 Risk Assessment
This section focuses on profiling hazards specific to the City of Calistoga and assessing their vulnerability independent of the broader county-wide planning area, which has been evaluated in Section 3 of Volume 1.

The hazard profiles in Volume 1 discuss overall impacts to the planning area and describe relevant plans, CAL OES SUBMITTAL - JUNE 2026
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policies, and regulations; past events; location; frequency and probability of future occurrences; severity and extent; warning time; secondary hazards; and climate change impacts. For more information on risk assessment methodologies, see Volume 1, Appendix A.

This section includes a tailored vulnerability assessment, analyzing assets at risk such as population, property, and critical facilities and infrastructure unique to the city, and information on city-specific differences in hazard vulnerability across the planning area. It also identifies total city assets at risk, including people, property, and critical facilities and infrastructure within the city. In addition, this section presents growth and development trends for the community, offering insights into vulnerabilities and risks that represent the broader context of assets at risk.

2.5.1 Hazard Screening & Prioritization
Members of the Planning Team from each participating jurisdiction came together to collaboratively decide which county-wide hazards would be included in the MJHMP, and which would be excluded. Hazard screening and prioritization took place early in the process and integrated historic data, local knowledge, and consensus opinions to create a risk assessment matrix for the county as well as for each participating jurisdiction. These matrices indicate the priority of hazards prior to further refinement. Details about this process, the results of the discussion, and in-depth profiles for county-wide hazards can be found in Volume 1, Sections 2 and 3.

The City of Calistoga’s internal planning group used the same hazard identification and prioritization process as the county-wide Planning Team. They reviewed previously prepared hazard mitigation plans and other relevant documents to determine the realm of natural hazards that have the potential to affect the city. Table 2-10 provides a crosswalk of hazards identified in select planning documents, including the 2020 Napa County MJHMP, the City of Calistoga General Plan, and the 2023 State of California HMP. The crosswalk was used to develop a preliminary hazards list, providing a framework for the group to evaluate which hazards were truly relevant to the City of Calistoga and which ones were not.

The internal planning group then ranked hazards based on their probability of affecting City of Calistoga and potential impacts on the community. Figure 2-10 displays the results of the hazard risk ranking exercise that was performed before further refinement. All hazards have been profiled in Volume 1 of this document.

The purpose of this annex is to specifically address the city’s vulnerability to specifically identified hazards.

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Table 2-10: City of Calistoga Document Review of Potential Hazards Hazard 2020 Napa County
MJHMP
City of Calistoga General
Plan
2023 California
SHMP
Agricultural Pests ■ ■
Avalanche ■
Climate Change ■ ■ ■
Coastal ■
Dam Failure ■ ■
Drought ■ ■ ■
Earthquake / Liquefaction ■ ■ ■
Extreme Cold ■
Extreme Heat ■ ■
Extreme Weather / Storms ■ ■ ■
Flood ■ ■ ■
Geologic / Mass Movement ■ ■ ■
Human-Caused ■
Insects ■
Levee Failure ■
Pandemic Disease ■ ■
Sea Level Rise ■
Soil ■
Subsidence ■
Tornado ■
Tsunami / Seiche Wave ■
Volcano ■
Wildfire ■ ■ ■
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Figure 2-10: City of Calistoga Risk Assessment Matrix
Note: Hazard naming in the Risk Assessment Matrix may not match the final naming used. Refer to hazards prioritization summary table.

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Priority Hazards
The results of the initial risk ranking exercise completed by the city’s Planning Team, before further refinement, are identified in the county’s completed matrix in Figure 2-10. Table 2-11 provides the final list of priority hazards and subhazards with additional details about why certain hazards were chosen and why others were not prioritized. However, it should be noted that many hazards not prioritized for profiling are briefly discussed as secondary or compounding hazards, and subhazards that were profiled and included in the risk assessment are listed specifically.

Table 2-11: City of Calistoga Hazards Prioritization Summary Hazard Priority Explanation
Earthquake / Liquefaction Medium Profiled in Volume 1, Section 3.3.4, and Section 2.5.2.2 in this annex, including Liquefaction
Wildfire Extreme Profiled in Volume 1, Section 3.3.1, and Section 2.5.2.1 in this annex Flood Medium Profiled in Volume 1, Section 3.3.2, and Section 2.5.2.3 in this annex, not including Levee Failure due to no exposure
Levee Failure - Profiled in Volume 1, Section 3.3.2; not a priority due to no exposure Extreme Weather / Storms High
Profiled in Volume 1, Section 3.3.5, and Section 2.5.2.6 in this annex as Severe Weather, including High Wind and Heavy Rain (Winter Weather not a priority due to low probability and impact potential) Drought High Profiled in Volume 1, Section 3.3.6, and Section 2.5.2.4 in this annex Geologic / Mass Movement -
Profiled in Volume 1, Section 3.3.5; not a priority due to low probability and impact potential
Extreme Heat Medium Profiled in Volume 1, Section 3.3.8, and Section 2.5.2.5 in this annex Agricultural Pests High Profiled in Volume 1, Section 3.3.9, and Section 2.5.2.7 in this annex under Climate Change as part of Agricultural Impacts
Sea Level Rise - Profiled in Volume 1, Section 3.3.9; not a priority due to no exposure Climate Change High
Profiled in Volume 1, Section 3.3.9, and Section 2.5.2.7 in this annex, including Agricultural Impacts, and discussed as a compounding hazard in relevant profiles
Dam Failure -
Profiled in Volume 1, Section 3.3.3; not a priority due to low probability and impact potential
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2.5.2 Vulnerability to Specific Hazards
Assessing vulnerabilities exposes the unique characteristics of individual hazards and begins the process of narrowing down which areas within the city are vulnerable to specific hazard events. The vulnerability assessment considered unique local knowledge of hazards and impacts and a GIS overlaying method for examining such vulnerabilities in more depth. Using these methods, the city’s planning group estimated vulnerable populations, properties, and assets, and potential losses. In addition, the exposure of city assets to drought, geological, earthquake, wildfire and flood hazards were also considered.

Many of the hazard profiles include a snapshot map and damage estimation tables that illustrate the city’s vulnerabilities to those specific hazards. These maps assisted the planning group in understanding the hazard exposure of populations, parcels, and critical facilities and infrastructure. Each snapshot map contains an exposure summary that displays the percentage of the population, the improvement and content value of parcels, and the amount of critical infrastructure that is exposed. For hazards without geospatial extents, such as drought and severe weather, narratives are provided instead of exposure maps and tables.

Based on the hazard prioritization exercise, this vulnerability assessment focuses on seven hazards for the City of Calistoga, some of which encompass sub hazards such as Liquefaction and Heavy Rain.

Wildfire
SECTION 0
Earthquake
SECTION 2.5.2.2
Flood
SECTION 2.5.2.3
Drought
SECTION 2.5.2.4
Extreme Heat
SECTION 2.5.2.4
Severe Weather
SECTION 2.5.2.6
Climate Change
SECTION 2.5.2.7
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Wildfire Hazard
Wildfire risk in the City of Calistoga is primarily concentrated along the eastern and western edges of the community, where developed areas interface with open space, wetlands, and the Mayacamas Mountains and the Howell Mountains. The wildfire risk exposure map, Figure 2-11, shows that portions of the city and surrounding Sphere of Influence are located within Moderate, High, and Very High Fire Hazard Severity Zones, particularly in areas adjacent to undeveloped land and wildland vegetation.

The eastern boundary of Calistoga, which transitions into rolling hills and open space east of Highway 29 and near Silverado Trail, is characterized by Very High wildfire hazard. These areas contain dense vegetation on steep slopes that can dry rapidly during summer and fall months, increasing the potential for fast-moving fires under windy or extreme heat conditions. Residential neighborhoods, resorts, and wineries located near this wildland–urban interface (WUI) may face heightened risk related to ember intrusion, evacuation constraints, and access limitations during wildfire events. Exposure summaries indicate that approximately 700 residents, more than 250 parcels, nearly $242 million in building improvement value, and $131 million in content value fall within Very High Fire Hazard Severity Zones. However, over half of the total city population (about 2,700 people) live in Moderate to Very High zones.

More than 50% of the land within city limits is located within a Fire Hazard Severity Zone, with many residents, properties, and public assets exposed. As shown in Figure 2-11, population, parcel, and critical infrastructure exposure rates within Very High hazard zones are approximately 12%. This reflects Calistoga’s relatively urbanized development pattern with extensive WUI areas in high-risk wildfire terrain surrounding the city core.

Wildfire risk and exposure are important planning considerations in Calistoga due to dense past development that extends into High and Very High hazard areas along the city edges, regional wildfire activity, and secondary impacts such as smoke exposure, power shutoffs, transportation disruptions, and evacuation demands. Increasing the threat of wildfire is the city’s lack of water suppression due to aging pipes, lack of water system looping for redundancy, and pipe materials susceptible to fire. There is a great need to increase water delivery reliability for fire protection in these WUI areas.

Of particular concern in the WUI is Calistoga’s growing senior population. As past wildfire evacuations over the last decade have demonstrated, growing mobility limitations among the aging population create additional challenges during a fast-moving event and warrant special attention in mitigation and emergency planning.

Climate change projections indicating hotter temperatures, longer dry seasons, and increased frequency of extreme weather events are expected to exacerbate wildfire conditions throughout Napa County, including areas surrounding Calistoga. To address Calistoga’s future needs, a new Emergency Operations Center is needed. During past wildfire events, the city fairgrounds were used for sheltering and incident comment, including for the Valley Fire in 2015, the Tubbs Fire in 2017, and the Pickett Fire in 2025.

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Figure 2-11: Exposure Summary – City of Calistoga Wildfire Risk CAL OES SUBMITTAL - JUNE 2026
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Earthquake Hazard
The City of Calistoga is subject to significant earthquake risk due to its location within the seismically active San Francisco Bay Area and proximity to multiple active faults in Napa County and the surrounding region.

Earthquake impacts in the city are best illustrated through scenario modeling, including the Hunting Creek– Berryessa Earthquake Scenario (Magnitude 7.1) and the West Napa Earthquake Scenario (Magnitude 6.7).

These scenarios reflect credible seismic events that could produce strong to severe ground shaking throughout the city.

Under the Hunting Creek–Berryessa M7.1 scenario (Figure 2-12), ground shaking across Calistoga is generally characterized as Strong (Modified Mercalli Intensity [MMI] VI). Exposure summaries indicate that approximately 300 residents, 200 parcels, nearly $78 million in building improvement value and $42 million in content value fall within these intensity ranges. In addition, all mapped critical infrastructure categories, including essential facilities, hazardous materials sites, high potential loss facilities, and transportation and lifeline systems, are exposed to damaging levels of ground shaking.

The West Napa Earthquake M6.7 scenario, Figure 2-13, represents a less impactful event for Calistoga. Under this scenario, 100 percent of the City’s population, parcels, and assessed parcel value are exposed to Moderate to Strong (MMI V–VI). While exposure summaries indicate no population, parcels, or critical infrastructure located in the highest modeled intensity categories for this scenario within city limits, the widespread nature of strong shaking suggests the potential for damage to buildings, infrastructure, and lifelines, particularly older structures and non-ductile construction.

Earthquake impacts associated with these scenarios include structural damage to residential, commercial, and industrial buildings; failure of non-structural components; disruption of transportation corridors such as Highways 29, 128, and Silverado Trail; and damage to utilities including water, recycled water, wastewater, stormwater, power, and communications systems. Existing pipelines for wet utilities, in particular, are aging and made of brittle materials that are highly susceptible to breaks and leaks.

Secondary earthquake hazards also present a concern for Calistoga. These include hazardous materials releases from industrial and commercial facilities, fires following earthquakes, prolonged power outages, and limited access for emergency response due to damaged roadways or bridges. Given the city’s strategic location in the upper Napa Valley, such disruptions could have regional economic and public safety consequences.

Liquefaction
Liquefaction represents a significant secondary earthquake hazard for the City of Calistoga due to local soil conditions, groundwater characteristics, and location on the Napa River (Figure 2-14). Liquefaction occurs when saturated, loose, fine-grained soils temporarily lose strength during intense ground shaking, causing the ground to behave more like a liquid. This phenomenon can result in ground settlement, lateral spreading, loss of bearing capacity, and damage to buildings, roadways, and buried utilities. While liquefaction is a CAL OES SUBMITTAL - JUNE 2026
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consideration in hazard mitigation planning, it is not profiled as a standalone hazard but addressed as a secondary earthquake effect.

Liquefaction can significantly amplify earthquake impacts by damaging lifeline infrastructure such as water, wastewater, storm drainage, gas, and telecommunications systems. Buried pipelines may rupture or become misaligned, roadways and bridges may settle or deform, and access routes needed for emergency response may be compromised. Commercial areas located on susceptible soils may face additional risks related to hazardous materials releases if tanks, pipelines, or containment systems are affected.

The earthquake scenario analyses for Calistoga indicate that strong to very strong ground shaking (MMI VII–VIII) is likely under credible seismic events. When combined with local liquefaction-prone soils, these shaking intensities increase the potential for widespread ground failure in susceptible areas. As a result, liquefaction poses a threat not only to individual structures but also to the city’s broader functionality and recovery following a major earthquake.

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Figure 2-12: Exposure Summary – City of Calistoga Earthquake Risk (M7.1 Hunting Creek–Berryessa) CAL OES SUBMITTAL - JUNE 2026
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Figure 2-13: Exposure Summary – City of Calistoga Earthquake Risk (M6.7 West Napa) CAL OES SUBMITTAL - JUNE 2026
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Figure 2-14: City of Calistoga Liquefaction Risk
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Flood Hazard
Flooding is a significant natural hazard for the City of Calistoga due to its location on the Napa River.

Portions of the City are subject to riverine flooding during major precipitation events. Flood hazard areas within Calistoga are concentrated along the Napa River.

The FEMA Flood Risk Exposure map, Figure 2-16, shows areas within the 100-year (1% annual chance) and 500-year (0.2% annual chance) floodplains, including mapped floodway areas. There are no areas in the city protected by levee. These flood-prone areas reflect the combined influence of river overflow and constrained drainage capacity. Flood hazards in these areas may be exacerbated during extreme storm events when high river flows coincide with elevated bay water levels.

Exposure analysis indicates that about 1,300 residents, 150 parcels, $90 million in building improvement value, and $51 million in contents value are at risk of flooding. While no hazardous materials sites are located within the mapped flood hazard areas, several transportation and lifeline facilities intersect flood-prone zones and the city’s wastewater treatment plant is located in the FEMA Regulatory Floodway, highlighting the potential for access disruptions and service interruptions during flood events.

Flooding in Calistoga can result in structural damage to buildings, roadway inundation, utility system impacts, and long-term economic disruption. Repetitive or prolonged flooding may also affect industrial and commercial areas near the river, compounding recovery challenges. Secondary impacts include erosion and sediment deposition. A severe flood could damage bridges, water, wastewater, recycled water, and storm drainage facilities. The city has 40 plus critical facilities and 10 miles of wet utilities located in flood hazard areas. Old, aging infrastructure that is highly susceptible to flood damage and in need of replacement is a significant threat to the community.

Climate change is expected to increase flood risk in Calistoga over time. More intense precipitation events, may expand flood extents, increase flood depths, and reduce the effectiveness of existing drainage systems.

Areas currently mapped within the 500-year floodplain may experience more frequent flooding in the future, increasing exposure to residents, infrastructure, and economic assets.

National Flood Insurance Program
The National Flood Insurance Program (NFIP) makes federally backed flood insurance available to homeowners, renters, and business owners in participating communities. FEMA has prepared a detailed Flood Insurance Study (FIS) for Napa County and municipalities. The study presents water surface elevations for floods of various magnitudes, including the 1% annual chance flood (100-YR flood) and the

0.2% annual chance flood (500-YR flood). Base flood elevations and the boundaries of the 100- and 500-YR floodplains are shown on Flood Insurance Rate Maps (FIRMs), which are the principal tools for identifying the extent and location of the flood hazard. FIRMs are the most detailed and consistent data source available, and for many communities they represent the minimum area of oversight under their floodplain management program. See Section 4 of Volume 1 for general information on the NFIP.

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The City of Calistoga has participated in the NFIP since 1979 and has adopted the most recent FIRMs and FIS issued by FEMA (dated September 26, 2008) as well as local floodplain development regulations in compliance with the minimum NFIP standards (Calistoga Municipal Code Title 18). These minimum standards include procedures and provisions for substantial improvements and substantial damages to existing structures, the latter of which are employed by the floodplain administrator and city building inspectors following any hazard event affecting structures located in the flood hazard area in accordance with NFIP requirements. Regulations for substantial improvements are enforced via permitting procedures.

Implementation and enforcement of the city’s floodplain regulations are assigned to the Floodplain Administrator.

The City of Calistoga is currently in good standing with the provisions of the NFIP. Compliance is monitored by FEMA regional staff and by the California Department of Water Resources under a contract with FEMA.

Maintaining compliance under the NFIP is an important component of flood risk reduction. See Table 2-12 for more information on the City’s policies and historic flood insurance claims.

Table 2-12: City of Calistoga National Flood Insurance Program Information City of Calistoga NFIP Status and Flood Insurance Statistics NFIP Status Participating Since 9/28/1979
Community Identification (CID) 060206
CRS Class (Entry Date) N/A
Policies in Force (Total Coverage) 63 ($21,931,000 in Coverage) Policies Inside SFHA / Outside SFHA 43 Inside / 20 Outside Policies in Coastal Zones (Total Coverage) N/A
Total Claims (Total Paid) 16 Claims ($43,434 Paid)
Repetitive Loss (RL) / Severe Repetitive Loss (SRL) Properties No RL or SRL Properties Repetitive Loss Payments No RL Payments
Note: The number of policies is by property and does not count policies for individual buildings. The Privacy Act of 1974 (5 USC 522a) restricts the release of certain types of data to the public. Flood insurance policy and claims data is included in the list of restricted information. FEMA can only release such data to state and local governments, and only if the data is used for floodplain management, mitigation, or research purposes. Therefore, this plan does not identify the repetitive loss properties or include claims data for any individual property.

Principal Flooding Sources
The principal flooding source for the City of Calistoga is the Napa River. Riverine flooding from the Napa River is the primary driver of mapped flood risk in Calistoga. During major storm events, high river flows can overtop banks or exceed channel capacity, particularly where development and infrastructure are adjacent to the river.

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Figure 2-15: City of Calistoga Flood Risk (FEMA Zones and DWR Awareness Zones) CAL OES SUBMITTAL - JUNE 2026
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Figure 2-16: Exposure Summary – City of Calistoga Flood Risk (FEMA Zones) CAL OES SUBMITTAL - JUNE 2026
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Drought Hazard
The National Drought Monitor provides drought data and maps nationally and on a localized, watershed scale. The National Drought Monitor is the product of 11 agencies, including the NDMC, NOAA and USDA, and is available at http://droughtmonitor.unl.edu/. The National Drought Monitor categorizes the level of drought from D0 through D4, with D4 being the highest “exceptional drought.” Table 2-13 depicts drought classifications and impacts from the level of drought occurrence in California, while Figure 2-17 shows a time series of the level of drought in Napa County from 2000 to 2025 according to the National Drought Monitor.

Drought is a recurring and long-term hazard for the City of Calistoga due to California’s Mediterranean climate, variable precipitation patterns, and increasing impacts from climate change. Periods of prolonged below-average rainfall, reduced snowpack in the Sierra Nevada, and higher temperatures can significantly affect regional water supplies, ecosystems, and community resilience. Although drought does not typically cause immediate physical damage like other hazards, its cumulative impacts can be widespread and longlasting.

Calistoga relies on a combination of surface water and imported water supplies that are vulnerable to regional drought conditions. Extended drought periods can reduce available water supplies, increase demand during hotter and drier conditions, and place stress on water delivery systems. Drought conditions may also require implementation of mandatory water conservation measures, affecting residents, businesses, landscaping, and industrial operations and increasing their cost in water.

Drought can exacerbate other natural hazards affecting Calistoga. Dry conditions increase vegetation stress and fuel loads, elevating wildfire risk in surrounding grasslands and open space areas. Reduced soil moisture can also contribute to land subsidence, soil instability, and increased erosion during subsequent storm events. In addition, drought can degrade wetlands and riparian habitats along the Napa River and bayfront, reducing their natural flood attenuation and ecological functions.

Economic impacts of drought may include increased operational costs for businesses, reduced agricultural productivity in the surrounding region, and higher household expenses related to water use restrictions or rate adjustments. Vulnerable populations, including low-income households and elderly residents, may be disproportionately affected by higher utility costs and reduced access to cooling and water resources during extreme heat events associated with drought.

Climate change projections indicate that drought conditions in California are likely to become more frequent and severe, with longer dry periods punctuated by fewer but more intense storm events. These trends increase uncertainty in water supply reliability and place additional importance on long-term water resource planning, conservation, and resilience measures. For future drought resilience, there is a for Calistoga to increase its reservoir storage capacities, find additional water supplies for sustained drought emergencies, and to improve water supply delivery systems to make them more reliable.

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Table 2-13: Drought Classifications and Impacts
Category Description Possible Impacts
D0
Abnormally
Dry
▪ Soil is dry; irrigation delivery begins early
▪ Dryland crop germination is stunted
▪ Active fire season begins
D1
Moderate
Drought
▪ Dryland pasture growth is stunted; producers give supplemental feed to cattle ▪ Landscaping and gardens need irrigation earlier; wildlife patterns begin to change ▪ Stock ponds and creeks are lower than usual
D2
Severe
Drought
▪ Producers increase water efficiency methods and drought-resistant crops ▪ Grazing land inadequate
▪ Fire season is longer, with high burn intensity, dry fuels, and large fire spatial extent, more fire crews on staff
▪ Lake- and river-based tourism declines; boat ramps close ▪ Trees are stressed; plants increase reproductive mechanisms; wildlife diseases increase
▪ Water temperatures increase; programs to divert water to protect fish begin ▪ River flows decrease; reservoir levels are low and banks are exposed D3
Extreme
Drought
▪ Federal water is not adequate to meet irrigation contracts; extracting supplemental groundwater is expensive
▪ Fire season lasts year-round; fires occur in typically wet parts of the state; burn bans are implemented
▪ Ski and rafting business are low; mountain communities suffer ▪ Low water levels impede fish migration and cause lower survival rates ▪ Wildlife encroaches on developed areas; little native food and water is available for bears, which hibernate less
▪ Water sanitation is a concern; reservoir levels drop significantly; surface water is nearly dry; flows are very low; water theft occurs
▪ Livestock need supplemental feed, cattle and horses are sold; little pasture remains ▪ Well and aquifer levels decrease; homeowners drill new wells D4
Exceptional
Drought
▪ Fire season is very costly; number of fires and areas burned are extensive ▪ Many recreational activities are affected
▪ Fields are left fallow; orchards are removed; vegetable yields are low; honey harvest is small; agricultural unemployment is high, food aid is needed ▪ Fish rescue and relocation begin; pine beetle infestation occurs; forest mortality is high; wetlands dry up; wildlife death is widespread; algae blooms appear ▪ Poor air quality affects health: greenhouse gas emissions increase as hydropower production decreases; West Nile outbreaks rise
▪ Water shortages are widespread; surface water is depleted; federal irrigation water deliveries are curtailed; water prices are extremely high; wells are dry, more and deeper wells are drilled; water quality is poor
Source: Adapted from U.S. Drought Monitor Drought Classifications and Impacts CAL OES SUBMITTAL - JUNE 2026
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Figure 2-17: Drought Severity Timeline 2000-2024
Extreme Heat Hazard
Calistoga’s inland valley location and reliance on outdoor agricultural labor make it particularly sensitive to rising temperatures and more frequent extreme heat days. Climate change is projected to increase both the frequency and intensity of heat waves in the region, posing growing risks to public health, agriculture, and infrastructure.

Heat waves are becoming more common across California, with projections showing a significant rise in the number of extreme heat days by mid-century. According to Cal-Adapt, Calistoga will likely experience a climate change-driven increase in extreme heat days above 101.2°F from four days per year to 21 days per year by the end of the century under a medium emissions scenario (RCP 4.5). Over the same time period, the city is also likely to see an increase in warm nights above 60.1°F from four per year to 39.

In Calistoga, outdoor workers face elevated risks during extreme heat events, particularly those without access to shaded rest areas, cooling stations, or protective equipment. Seniors, low-income residents, and individuals in older housing stock without air conditioning are also especially vulnerable to heat-related illness and may lack transportation to reach cooling centers.

The city’s population exposure is compounded by socioeconomic factors. Many households in Calistoga are cost-burdened and lack adaptive measures such as air conditioning or urban tree canopy coverage, increasing health risks during prolonged heat events. This mirrors statewide findings that low-income and minority populations are disproportionately affected by extreme heat. Additionally, the city is more vulnerable to unplanned electrical outages during peak usage times.

As mentioned in Section 2.2.2, Calistoga is considered an Equity Priority Community by the Metro Transit Commission due in large part to its high senior population. Senior populations are at a much higher risk of heat related illnesses and an increased risk of death. Additionally, many seniors who are living in mobile CAL OES SUBMITTAL - JUNE 2026
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home parks experience significant impacts of high heat. Emergency managers should consideration senior mobility to cooling centers and funding and distribution of generators.

The frequency of extreme heat days is projected to rise significantly across inland Napa County by midcentury. For Calistoga, this means disproportionate impacts on agricultural workers in the Napa Valley as well as low-income neighborhoods with limited adaptive capacity. By the end of the century, the number of warm nights—when temperatures remain elevated and prevent recovery from daytime heat—is also projected to increase dramatically.

Extreme heat often coincides with elevated wildfire risk, reduced air quality from ozone and particulates, and public safety power shutoffs designed to prevent utility-caused ignitions. These secondary hazards can compound vulnerabilities by cutting access to cooling or disrupting medical care reliant on electricity.

Severe Weather Hazard
Severe storms are a recurring hazard in Calistoga, typically driven by high winds, heavy rainfall, and atmospheric river events during the winter months. While tornadoes, hail, and snow are rare in the region, severe storm impacts can be significant due to the city’s vulnerable infrastructure, older housing stock, and concentrations of at-risk populations.

Residents in mobile homes and older housing, many of whom are low-income or elderly, are particularly vulnerable during storm events. These households face heightened risks from power outages, mobility limitations, and health impacts during prolonged high-wind or heavy-rain events.

High winds frequently cause downed trees and power lines in and around Calistoga, leading to widespread power outages, communication disruptions, and blocked roadways. Such conditions strain emergency response capabilities, delay evacuations, and exacerbate challenges for dependent populations.

Heavy rainfall during atmospheric river events can overwhelm Calistoga’s aging stormwater infrastructure, especially in older downtown areas and low-lying neighborhoods near culverts and sloughs. These localized flash floods result in hazardous road conditions, temporary isolation of neighborhoods, and damage to property and infrastructure.

Severe storm frequency and intensity are projected to increase because of climate change. Calistoga already faces winter storms and recurring atmospheric rivers, which are contributing to repeated road closures, localized flooding, and long-term infrastructure strain. Climate-driven changes to storm severity highlight the city’s continued vulnerability to cascading hazards, including flooding and slope instability along the slough system.

While severe storms in Calistoga may not produce catastrophic destruction, their compounding effects on vulnerable populations, lifeline infrastructure, and mobility make them a critical hazard for ongoing mitigation planning. Strategies to reduce risk should prioritize hardening power and drainage systems, enhance stormwater infrastructure, and develop targeted preparedness and response measures that reach the city’s most at-risk residents.

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Climate Change Hazard
Average annual temperatures across most of California have already increased by more than 1°F, with some areas experiencing rises of over 2°F when comparing the 1901 to 1960 average to that of 1986 to 2016. Daily maximum temperatures—a key indicator of extreme heat—are projected to increase by 4.4°F to 5.8°F by 2050 and by 5.6°F to 8.8°F by 2100. Heat waves that impact public health, known as heat-health events, are also expected to intensify across the state. By 2050, these events are projected to last up to two weeks longer in the Central Valley and occur four to ten times more often in the Northern Sierra region (California Natural Resources Agency, 2022).

California is already experiencing significant impacts from climate change, including prolonged drought, a lengthened wildfire season, increased coastal flooding and erosion, increased impacts from severe weather events including high winds, and widespread tree mortality. The state has observed rising average temperatures, more extreme heat days, fewer cold nights, a longer growing season, and shifts in the water cycle, with less winter precipitation falling as snow. In addition, summertime fog has declined by approximately 33%, and both snowmelt and rainwater runoff are occurring earlier in the year (Cal OES, 2018).

Long-term trends indicate a 12% to 20% decline in fog across California from 1900 through projections to 2070. Climate experts suggest that warming temperatures reduce the ability of air masses to cool enough to produce fog, which plays a critical role in supporting California’s ecosystems (Grantham, Teodore; University of California, Berkeley, 2018).

The City of Calistoga is increasingly vulnerable to the long-term impacts of climate change, which function as hazard multipliers across the Napa Valley and broader North Bay region. Calistoga’s location near the San Pablo Bay and surrounding upland areas, creates a complex climate setting that is sensitive to shifts in temperature, precipitation patterns, and seasonal variability. Projected changes in these conditions are expected to intensify existing hazards, including flooding, drought, extreme heat, and wildfire.

While marine influences can moderate temperatures at times, these effects may be reduced during offshore wind conditions or prolonged high-pressure systems, allowing heat to build across the area. As temperatures continue to rise, the frequency and duration of extreme heat events are expected to increase, placing additional stress on vulnerable populations such as older adults, children, outdoor workers, and residents without access to adequate cooling. Increased heat also drives higher energy demand, placing strain on the electrical grid and increasing the likelihood of service disruptions.

Agricultural Impacts
The local agricultural and wine industry and related businesses provide an annual economic impact of more than $11.7 billion locally and nearly $36.7 billion nationwide, with Calistoga and the surrounding unincorporated areas being an important production area in the Napa Valley. According to a 2012 California Energy Commission report “Vulnerability and Adaptation to Climate Change in California Agriculture”, change in climate can directly impact crop growth through new temperature and precipitation patterns and northward shifts of pests and disease. Wildfire is also a major threat to agriculture in the Napa Valley.

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A significant exotic pest infestation could affect everyone in the county, through the loss of markets for farm products, increased pesticide usage and production costs. (Pests & Diseases, n.d.) If left unchecked, these pests can cause millions of dollars of damage to agriculture and trigger an increase in pesticide usage within the county. The Napa County Agricultural Commissioner's Office is concerned about the introduction of new, exotic and destructive organisms. (Napa Dep't of Ag./ Sealer of Weights & Measures, 2017) The most significant secondary hazard associated with an agriculture disaster is wildfire. Severe infestation of pests and disease in agricultural lands can cause crops to die, creating increased fuel for wildfire.

Agricultural lands are open areas with a mix of grasses, shrubs, trees, and crops that, if dried out or dead, could easily ignite and either start or contribute to wildfire.

2.5.3 Climate Change Impacts & Vulnerable Populations
Climate change is expected to exacerbate many of the natural hazards affecting the City of Calistoga, increasing risks to populations that already face social, economic, or physical vulnerabilities. Rising temperatures, more extreme precipitation events, prolonged drought, sea level rise, and increased frequency of extreme heat are projected to intensify existing hazard conditions and create new challenges for public health, safety, and emergency response.

Certain populations in Calistoga are more likely to experience disproportionate impacts from climaterelated hazards. Older adults, individuals with disabilities, low-income households, renters, and households with limited English proficiency may have reduced capacity to prepare for, respond to, and recover from climate-driven events. These groups may face barriers related to mobility, access to transportation, financial resources, housing stability, or timely access to emergency information.

Extreme heat presents a growing risk to vulnerable populations, particularly elderly residents, individuals with underlying health conditions, outdoor workers, and households without adequate cooling. Heat waves can increase the incidence of heat-related illness, strain electrical systems, and worsen air quality, especially when combined with wildfire smoke. Low-income households may be less able to afford cooling costs or make energy-efficient upgrades, increasing exposure during prolonged heat events.

Flooding and disproportionately affect residents and workers in low-lying areas near the Napa River.

Vulnerable populations living or working in these areas may face greater risk of displacement, property damage, and disruption of access to essential services. Flood events can also impact transportation routes and utilities, creating additional challenges for individuals who rely on public transit, medical equipment, or nearby services.

Drought and water scarcity can place added burdens on vulnerable populations by increasing utility costs, limiting access to cooling and landscaping, and reducing the resilience of natural systems that provide flood protection and cooling benefits. For low-income households and fixed-income seniors, increased water and energy costs associated with drought and heat can compound financial stress.

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Climate change may also increase the frequency and duration of poor air quality events, particularly from regional wildfires. Individuals with respiratory conditions, older adults, children, and outdoor workers are especially sensitive to smoke exposure. Limited access to air filtration, clean indoor environments, or protective equipment can further increase health risks for vulnerable populations.

2.5.4 Hazard Problem Statements
As part of the mitigation action identification process, the Planning Team for each jurisdiction identified areas of concern (aka problem statements) for their respective facilities based on the risk assessment and vulnerability analysis, utilizing the RAMP mapping and static snapshot maps. Problem statements focused on the impact, victim, or threat that the hazard could create in the jurisdiction, as described in Table 2-14.

Identifying common issues and weaknesses through these problem statements assisted the planning group in understanding the realm of resources needed for mitigation.

The goal is to have at least one mitigation action for every problem statement. Projects or actions have been developed to mitigate each problem identified. See Table 2-16 for a full list of mitigation actions and corresponding problem statements that they address. Each problem statement is coded with a problem number for cross-referencing between Table 2-14 and Table 2-16 Table 2-14: City of Calistoga Hazard Problem Statements Problem No. Hazard Area of
Concern
Primary
Agency
Problem Description Related MA
ps-CC-CL-13 Climate
Change
Victim City of
Calistoga
Calistoga’s vulnerable populations, including
seniors, renters, and low-income families, face
increased cumulative risk from intersecting
climate change-driven hazards.
ma-CC-CL-11, maAH-CL-218, maCC-CL-219
ps-CC-CL-15 Climate
Change
Threat City of
Calistoga
Climate projections show increasing
frequency and intensity of hazards, including
extreme heat, severe weather, drought,
wildfire, and flood, that compound and
cascade risk across sectors.
ma-CC-CL-11, maCC-CL-219
ps-CC-CL-324 Climate
Change
Victim City of
Calistoga
The farms, vineyards, and other businesses
that rely on Calistoga’s tourism-based
economy are heavily impacted by climate
change-driven hazard events such as more
extreme droughts, wildfires, and weather.
ma-CC-CL-219
ps-CC-CL-325 Climate
Change
Impact City of
Calistoga
Climate change increases flood, wildfire,
severe weather, and drought related hazard
risks.
ma-CC-CL-219
ps-DR-CL-45 Drought Threat City of
Calistoga
Prolonged drought threatens Calistoga’s water
supply and agricultural/tourism-based
economy. The City’s reliance on limited local
sources makes it vulnerable to supply
shortages and restrictions.
ma-DR-NCo-24,
ma-DR-CL-220,
ma-DR-CL-22
ps-DR-CL-46 Drought Impact City of
Calistoga
Drought conditions exacerbate wildfire risk,
decrease water quality, increase agricultural
and groundwater demand, and stress
vegetation.
ma-DR-CL-21,
ma-DR-CL-22
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Problem No. Hazard Area of
Concern
Primary
Agency
Problem Description Related MA
ps-DR-CL-320 Drought Impact City of
Calistoga
Drought can cause reduced revenues from
utility fees, higher costs to purchase additional
supplies, state water restrictions, and
associated impacts on tourism.
ma-DR-CL-220,
ma-DR-CL-22
ps-DR-CL-321 Drought Victim City of
Calistoga
Approximately 7,000 people served by City
water are impacted when water restrictions
are triggered by extended drought, especially
agricultural operators.
ma-WF-CL-87,
ma-CC-CL-219,
ma-DR-CL-22,
ma-DR-CL-220
ps-EQ-CL-66 Earthquake Victim City of
Calistoga
All city residents live in areas with moderateto-high seismic hazard risk and are potentially exposed to impacts from a major earthquake,
including fire damage from broken gas lines.
ma-EQ-CL-34,
ma-EQ-CL-35
ps-EQ-CL-67 Earthquake Impact City of
Calistoga
A major earthquake could damage
transportation routes and utilities, including
aging water, sewer, recycle, and storm lines,
critically impacting continuity of City services,
challenging emergency response, and
disrupting access routes.
ma-EQ-CL-34,
ma-WF-CL-87
ps-EQ-CL-82 Earthquake Threat City of
Calistoga
Calistoga is exposed to seismic hazard risk
due to proximity to the West Napa and
Hunting Creek Berryessa Faults, which are
capable of producing M6.7+ earthquakes.
ma-EQ-CL-35,
ma-AH-CL-218
ps-EQ-CL-322 Earthquake Impact City of
Calistoga
A major earthquake could severely impact the
city’s economy, especially from lost tourism.
ma-EQ-CL-34,
ma-EQ-CL-35
ps-FL-CL-108 Flood Victim City of
Calistoga
There are many local businesses located in
and approximately 1,300 people living in the
100- or 500-year FEMA floodplain which are
exposed to potential flooding impacts.
ma-FL-CL-48,
ma-FL-CL-50,
ma-AH-CL-218
ps-FL-CL-111 Flood Impact City of
Calistoga
There are over 40 critical facilities (including
the fire station/EOC) and more than 10 miles of
critical infrastructure located in the 100- or
500-year FEMA floodplain. A severe flood
event could damage or destroy critical
infrastructure such as streets, bridges, water
and wastewater systems, or stormwater
conveyance, and could potentially
contaminate the City's water system and the
environment.
ma-FL-CL-48,
ma-FL-CL-50,
ma-WF-CL-87
ps-FL-CL-319 Flood Threat City of
Calistoga
Flood risk is expected to change due to
increased rainfall intensity from climate
change and changing river
vegetation/management and environmental
challenges maintaining waterways.
ma-CC-CL-219
ps-HH-CL-326 High Heat Threat City of
Calistoga
The frequency of extreme heat days and warm
nights is projected to rise significantly by midcentury, with disproportionate impacts on agricultural areas and low-income
neighborhoods, and those considered Equity
Priority Communities.
ma-AH-CL-218,
ma-CC-CL-219
ps-HH-CL-327 High Heat Victim City of
Calistoga
Seniors, socioeconomically disadvantaged
households, and those living in mobile homes
often do not have adequate air conditioning
and are disproportionately impacted by
extreme heat events.
ma-AH-CL-218
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Problem No. Hazard Area of
Concern
Primary
Agency
Problem Description Related MA
ps-HH-CL-328 High Heat Impact City of
Calistoga
Extreme heat events often cause power
outages from high demand during peak hours,
can trigger PSPS events, and exacerbate
wildfire and drought risks.
ma-AH-CL-218,
ma-AH-CL-3
ps-FL-CL-125 Severe Weather Impact City of
Calistoga
Heavy rain events cause localized flooding and
damage water, sewer, and recycling systems
due to aging and undersized storm drainage
infrastructure
ma-FL-CL-49,
ma-WF-CL-87
ps-SW-CL-145 Severe Weather Impact City of
Calistoga
High wind, heavy rain, and winter storm
events increasingly disrupt utilities and
transportation, including from downed trees
and powerlines and localized flooding,
resulting in blocked access and extended
power outages.
ma-SW-NCo-81,
ma-SW-NCo-82,
ma-AH-CL-218,
ma-WF-CL-87
ps-SW-CL-147 Severe Weather Threat City of
Calistoga
Severe winds can damage electrical
infrastructure, cause power outages, and spark
or exacerbate wildfire conditions.
ma-SW-CL-79,
ma-WF-CL-87
ps-SW-CL-323 Severe Weather Victim City of
Calistoga
Seniors, socioeconomically disadvantaged
households, and those living in mobile homes
often do not have adequate heat and are
disproportionately impacted by winter storms
and low temperatures.
ma-AH-CL-218,
ma-SW-CL-79
ps-WF-CL-179 Wildfire Threat City of
Calistoga
Calistoga is exposed to high wildfire risk due
to extensive WUI, fuels and topography on
surrounding lands, and a local climate prone to
fire weather conditions.
ma-WF-CL-87,
ma-WF-CL-88,
ma-WF-CL-89,
ma-WF-NCo-90,
ma-AH-CL-218,
ma-WF-CL-221
ps-WF-CL-183 Wildfire Victim City of
Calistoga
Over half of the population (approximately
3,000 residents) lives in High or Very High
FHSZs and are at increased risk of direct
wildfire impacts to safety and property while
insurance cancellations and high premiums
have increased.
ma-WF-CL-88,
ma-WF-NCo-90,
ma-AH-CL-218,
ma-WF-CL-221
ps-WF-CL-184 Wildfire Impact City of
Calistoga
A wildfire within or adjacent to City limits
could cause loss of life, evacuations,
destruction of property, and damage and
disruption to critical facilities and
infrastructure, in addition to business
disruptions and reduced tourism.
ma-WF-CL-88,
ma-AH-CL-3, maWF-CL-221
ps-WF-CL-317 Wildfire Victim City of
Calistoga
Indirect impacts of wildfire, such as power
shutoffs, smoke, and fire-related evacuations,
disrupt tourism and affect local businesses.
ma-AH-CL-218,
ma-AH-CL-3
ps-WF-CL-318 Wildfire Threat City of
Calistoga
The city lacks adequate fire suppression
capabilities due to aging pipes, dead ends in
the system (not looped), infrastructure made
with combustible materials, and inadequate
back-up power.
ma-WF-CL-87,
ma-AH-CL-3
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2.6 Mitigation Strategy
This section provides the framework for how the City of Calistoga will reduce hazard risk within its jurisdiction while supporting the broader goals of the Napa County MJHMP. It includes an overview of existing capabilities, opportunities to strengthen resilience, and the city’s prioritized mitigation actions.

Together, these elements demonstrate how Calistoga integrates hazard awareness into its planning and development processes while contributing to a coordinated countywide approach.

Within the Napa County MJHMP, the mitigation strategy serves as the roadmap for future hazard mitigation efforts. For Calistoga, the strategy outlined in this annex reflects the outcomes of the countywide planning process while also addressing the city’s unique risks, priorities, and community needs. The strategy is designed to reduce vulnerabilities identified in the risk assessment, including the problem statements developed for flooding, earthquakes and liquefaction, slope failure, wildfire, drought, severe storms, extreme heat, and climate change.

Mitigation actions identified in this annex include both policy-based and project-based initiatives, with an emphasis on integrating resilience into land use planning, infrastructure investments, and community programs. Actions are structured to align with FEMA’s requirements and to coordinate with existing city, county, and regional planning mechanisms. Each action identifies responsible parties, potential funding sources, and the resources needed for implementation.

For Calistoga, this strategy provides a framework for strengthening resilience by combining city-led initiatives, such as infrastructure improvements, building code enforcement, and community preparedness, with regional coordination through the MJHMP. By advancing these efforts in alignment with the General Plan and other local planning documents, Calistoga enhances its ability to reduce hazard risk while supporting long-term community safety, sustainability, and economic stability.

The subsections that follow describe these elements in detail:
▪ Sections 2.6.1, Capabilities and Opportunities, provides a summary of the city’s capacity to address natural hazards.
▪ Section 2.6.2, Mitigation Action Plan, presents Calistoga’s prioritized actions to guide implementation in coordination with countywide strategies. ▪ Section 2.6.3, Status of Previous Mitigation Actions, provides a summary of all previous actions and their current status, whether completed, cancelled, or revised.

Aligning the Action Plan
This section connects Calistoga’s mitigation actions with its existing capabilities and areas for growth.

Capability assessments are a required element of hazard mitigation planning under the Disaster Mitigation Act of 2000 and FEMA’s 2023 guidance, ensuring that actions are realistic, achievable, and aligned with available resources.

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The section begins with a summary of Calistoga’s capabilities across four areas: planning and regulatory, administrative and technical, fiscal, and education and outreach. This overview highlights the tools and strengths that the district already uses to reduce hazard risk. The section then provides a detailed analysis of each capability area, identifying both current practices and opportunities to expand resilience.

2.6.1 Capabilities & Opportunities
This section provides a detailed assessment of the city’s current capabilities to support hazard mitigation, as well as future opportunities. This consists of describing how the city is planning for hazards and growth and a summary of its existing capabilities and the potential for enhancement.

Planning for Hazards & Growth
As a general law city, the City of Calistoga manages growth within the framework of California’s comprehensive planning, zoning, subdivision, and environmental regulations. Much of the City’s developable land has already been urbanized, and remaining growth is largely directed toward infill development, redevelopment, and planned buildout within the existing urban footprint. Calistoga is bisected by the Napa River with hillside terrain to the west and east, which constrains outward expansion and concentrates future development in areas already subject to natural hazards.

This development pattern places portions of the city’s population, infrastructure, and economic assets within areas exposed to hazards such as wildfire in the city’s extensive WUI areas, riverine and flooding along the Napa River, strong earthquake ground shaking and liquefaction, and extreme heat and drought conditions. Commercial areas near the river corridor and residential neighborhoods in low-lying areas are particularly sensitive to flooding and sea level rise, while hillside areas west and east of the city face localized risks related to slope instability and wildfire exposure.

Hazard vulnerability is addressed through coordination with the city’s General Plan, particularly the Safety Element, which integrates hazard information into land use decisions, infrastructure planning, and development review. This approach ensures that growth and redevelopment consider site-specific risks and incorporate appropriate mitigation measures, such as flood-resilient design, geotechnical stabilization, and emergency access planning. Integration of hazard considerations into long-range planning also supports compliance with state and federal hazard mitigation requirements and strengthens the City’s eligibility for disaster recovery and resilience funding.

Climate change is expected to intensify several of the hazards affecting Calistoga, including wildfire, flooding influenced by sea level rise, more extreme precipitation events, prolonged drought, and increasing extreme heat. As growth continues within constrained and hazard-exposed areas, resilience must be embedded into every phase of planning and development. Growth management in Calistoga therefore emphasizes sustainable building practices, water conservation, protection of natural floodplain functions, and climate-adaptive infrastructure, ensuring that future development and redevelopment reduce, rather than exacerbate, existing hazard risks and support long-term community resilience.

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Long-Range Planning & Growth Management
Long-range planning and growth management policies play a central role in limiting hazard exposure in Calistoga. The city’s General Plan establishes the overall land use pattern, directs growth toward areas that can be safely and efficiently served by infrastructure, and discourages development in areas subject to significant natural hazards where feasible.

Growth in Calistoga has largely occurred within an established urban footprint on the valley floor, with an emphasis on infill development, redevelopment, and planned expansion areas that are supported by existing transportation, utility, and emergency services. This approach helps reduce the need for development in hazard-prone areas such as floodplains, steep slopes, and wildfire-prone wildland–urban interface locations. Where development does occur near hazard areas, planning policies emphasize hazardaware site design, infrastructure resilience, and emergency access.

Long-range planning efforts also account for future climate conditions, recognizing that sea level rise, extreme heat, drought, and more intense storm events may alter hazard profiles over time. Incorporating these considerations into growth management helps ensure that future development does not increase vulnerability or place undue strain on emergency response and public services.

Building Codes & Development Standards
Calistoga’s development strategies combine comprehensive planning frameworks with robust regulatory measures to guide growth while reducing risks from natural hazards. Building codes play a central role in this approach. Nationally, continual improvements to building codes since 1990 have added only about one percent to construction costs while greatly improving disaster resilience. In California, building codes are among the most stringent in the world, setting minimum standards that safeguard against hazards such as earthquakes, flooding, wildfire, landslides, and severe weather. Calistoga enforces these standards locally, providing a strong foundation for resilient construction.

The city is required to regularly update its development regulations to reflect the California Building Code (CBC), which is revised every three years and was most recently updated in 2025. The CBC establishes some of the world’s highest construction standards, ensuring occupant safety in the face of natural hazards.

Climate change is also addressed through adoption and updating of the California Green Building Standards (CALGreen) and Energy Codes, which integrate energy efficiency, sustainable design, and climate adaptation measures. In addition, Calistoga participates in the National Flood Insurance Program (NFIP), requiring that all new development in designated flood hazard areas meet FEMA’s minimum flood protection standards.

Through these building and development regulations, Calistoga ensures that new development in hazardprone areas is either restricted or subject to strict hazard-mitigation requirements. Where development is allowed, codes emphasize reducing exposure and vulnerability through appropriate siting, advanced construction techniques, emergency access, and defensible space. For example, new construction in the CAL OES SUBMITTAL - JUNE 2026
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wildland–urban interface (WUI) must comply with fire-resistant building materials and vegetation management requirements under the California Fire Code.

Beyond code enforcement, Calistoga integrates these mandates into broader local planning frameworks, including the General Plan and HMP This alignment ensures that growth management, environmental review, and hazard mitigation strategies collectively address emerging risks from wildfire, drought, flooding, extreme heat, and severe weather intensified by climate change.

California Environmental Quality Act (CEQA) & Hazard Mitigation The California Environmental Quality Act (CEQA) requires General Plans, Specific Plans, and major development projects to evaluate hazards such as flooding, seismic risk, and wildfire. Environmental documents must identify these risks and propose mitigation measures, which may include setbacks from hazard-prone areas, infrastructure upgrades, evacuation planning, or restrictions on development in highrisk zones.

Regional and state public safety planning frameworks that inform development review in Calistoga include the State Seismic Hazards Mapping Act, the California Environmental Quality Act (CEQA) and its Guidelines, California Noise Insulation Standards (Title 24), and the Federal Emergency Management Agency (FEMA) Flood Insurance Program. Together, these programs establish requirements for evaluating and mitigating environmental and hazard-related impacts associated with development.

Under CEQA, residential projects that require discretionary approval from the city are subject to environmental review concurrently with the approval process. While CEQA review can add time to development and is therefore considered a potential constraint to housing production, much of Calistoga’s remaining vacant and developable land has already undergone environmental review through Environmental Impact Reports (EIRs) prepared as part of adopted specific plans. These EIRs streamline subsequent project-level CEQA review by identifying environmental impacts and mitigation measures in advance, allowing later residential projects to tier from or rely on existing CEQA documents. Projects that deviate from the assumptions or scope of adopted specific plans may also tier from previously certified CEQA analyses, where appropriate.

Recent updates to CEQA standards have also changed how transportation and air quality impacts are evaluated. Transportation impacts are no longer assessed using Level of Service (LOS), which measured vehicle delay, but instead rely on Vehicle Miles Traveled (VMT) as the primary metric. This shift emphasizes reducing vehicle travel and associated emissions rather than roadway congestion.

In addition, updated Bay Area Air Quality Management District (BAAQMD) greenhouse gas (GHG) thresholds, adopted in April 2022, require changes to how GHG impacts are analyzed in CEQA documents. Under these standards, plans or projects within BAAQMD jurisdiction must either demonstrate consistency with an adopted, qualified local Climate Action Plan or incorporate specific project features, including all-electric buildings, a minimum reduction in VMT, and electric vehicle infrastructure meeting CalGreen Tier 2 requirements.

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Although LOS is no longer used for CEQA compliance, the city continues to use LOS analysis as a non-CEQA planning tool to evaluate roadway operations, support infrastructure planning, and ensure that key transportation corridors function effectively and meet community expectations. Together, CEQA and related regulatory frameworks play a critical role in integrating hazard mitigation, climate adaptation, and sustainability considerations into development and long-range planning decisions in Calistoga.

By integrating hazard analysis into the development review process, CEQA helps ensure that future growth in Calistoga is designed with resilience and long-term community safety in mind.

Development & Hazard Considerations
Development in the City of Calistoga occurs within a physical and regulatory context shaped by natural hazards, environmental constraints, and long-term growth management policies. As a general law city operating under California planning and environmental regulations, Calistoga evaluates development proposals with consideration for hazard exposure, public safety, infrastructure capacity, and long-term resilience. This integrated approach helps ensure that new development and redevelopment do not increase risk to people, property, or critical systems.

Much of the city’s remaining development potential lies within areas that are already urbanized or planned through adopted specific plans. As a result, development often occurs in proximity to known hazard areas, including floodplains along the Napa River, dam inundation zones, liquefaction-prone soils, and areas exposed to strong seismic shaking and extreme heat. Rather than avoiding development entirely in these locations, the city emphasizes risk-informed site planning, design, and construction standards to reduce vulnerability and limit potential impacts.

Flood hazards are addressed through enforcement of flood plain management regulations, participation in the National Flood Insurance Program, and incorporation of flood-resilient design measures for development in or near mapped flood hazard areas. These measures may include elevating structures, protecting utilities, maintaining flood conveyance, and avoiding critical facilities in the highest-risk locations. Development decisions also consider future flood conditions associated with sea level rise and more intense storm events.

Seismic hazards are a key consideration in development review due to the City’s location within the seismically active San Francisco Bay Area. Projects are required to comply with state seismic design standards and, where appropriate, conduct site-specific geotechnical investigations to address ground shaking, liquefaction, and slope stability. These requirements help reduce structural damage and protect infrastructure during earthquake events.

Wildfire, slope failure, and extreme weather hazards are also considered during development review, particularly in areas identified as moderate, high, or very high fire hazard severity zones, and those near the eastern hills, open space, and transportation corridors. Development standards related to defensible space, access, drainage, and emergency response are used to minimize risk and support safe evacuation and emergency operations.

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The CEQA provides a framework for identifying hazard-related impacts at the project level and requiring feasible mitigation measures. Through CEQA review, the city evaluates whether proposed development would expose people or structures to significant risks from natural hazards and ensures that appropriate avoidance, design, or mitigation measures are incorporated into project approvals.

Capabilities & Opportunities Assessment
To develop a realistic and actionable mitigation strategy, it must account for existing jurisdictional capabilities and what future opportunities there are to enhance those capabilities for purposes of hazard mitigation. This section provides an assessment of the City of Calistoga’s existing capabilities and future opportunities, including planning and regulatory, administrative and technical, fiscal, and public outreach and education capabilities. This assessment also identifies opportunities to integrate this MJHMP into future planning, policies, or programs to weave mitigation efforts into daily operations and address hazard problems wholistically. Capabilities are categorized into four groups and include various mechanisms. ▪ Planning and Regulatory Capabilities: Existing long-range plans, emergency response plans, hazard-specific plans, land use policies, and building and development standards. ▪ Administrative and Technical Capabilities: Available expertise in emergency services, engineering, grant management, and community planning.
▪ Fiscal Capabilities: Budgetary capacity, taxing authority, grants, and other funding mechanisms that can support mitigation projects.
▪ Outreach and Education Capabilities: Existing programs for providing technical assistance, community education, public warnings, and stakeholder engagement.

A full description of the process used to develop the capabilities assessment is provided in Volume 1, Section

2.3.3. This capabilities and opportunities assessment for Calistoga lists the various types of capabilities along with how they have been, currently are, or will in the future be integrated into hazard mitigation planning efforts.

The three “HMP Integration” columns that identify the capability’s status and usage are color-coded with green, yellow, or orange shading to communicate the following:
▪ Status: If the capability is present at all and what level of use it has generally. ▪ Current Mitigation Use: If the capability is currently being used in mitigation efforts, specifically, and at what level.
▪ Future Opportunity: If there is a future opportunity to integrate the capability into mitigation efforts and at what level.

Summary of Capabilities & Opportunities
This Capabilities and Opportunities Assessment for Calistoga summarizes the various types of capabilities it has for hazard mitigation currently. The assessment also identifies opportunities to integrate, expand, and CAL OES SUBMITTAL - JUNE 2026
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improve the city’s capabilities for future hazard mitigation. Table 2-15 provides a comprehensive list of capabilities and identifies the current status, current mitigation use, and future opportunities.

Planning & Regulatory
The City of Calistoga has strong planning and regulatory capabilities that support hazard risk reduction and resilient development. The city enforces the California Building Code (Title 24) and locally adopted ordinances that address floodplain management, fire safety, stormwater control, water conservation, and development in inundation and hillside areas. These regulations are integrated into zoning, subdivision, and site plan review processes, ensuring that hazard considerations are addressed during development reviews.

Growth management is guided by policies in the city’s General Plan. Capital investments are prioritized through the Capital Improvements Program (CIP), which supports resilient infrastructure for water, storm drainage, transportation, and public services.

Calistoga maintains several hazard reduction programs, including stormwater management and erosion control, water conservation, and public outreach through the Alert Napa County emergency preparedness webpage. The city also promotes non-structural earthquake preparedness and household-level mitigation actions.

The City participates in the National Flood Insurance Program (NFIP) and enforces local floodplain management regulations supported by current FEMA flood mapping and elevation certificate records. While flood preparedness information is available, flood insurance education is limited, and the City does not currently participate in FEMA’s Community Rating System (CRS), representing a future opportunity for enhanced flood risk reduction.

Future integration of the MJHMP will occur through various processes and mechanisms outlined across multiple mitigation actions (Table 2-16). A key opportunity for future hazard mitigation integration with the city’s existing planning mechanisms is to integrate the updated risk assessment and projected climate change impacts on hazards into the Climate Adaptation and Resilience Plan (ma-CC-CL-219).

Administrative & Technical
The City of Calistoga has strong administrative and technical capacity to support hazard mitigation planning, implementation, and coordination. Core planning, engineering, and development review functions are housed within the Planning & Building Department. These staff provide expertise in land use planning, development review, infrastructure design, and enforcement of building and safety standards.

The city has access to qualified personnel for key hazard mitigation functions, including community planning, land development review, construction engineering, natural hazards analysis, transportation planning, and resilience planning. The Building Division provides building code administration, and the City Manager serves as the Floodplain Administrator and Director of Emergency Services, ensuring direct CAL OES SUBMITTAL - JUNE 2026
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coordination between planning, emergency management, and floodplain compliance. Fire prevention and wildfire mitigation functions are supported by the Calistoga Fire Department through the Fire Marshal.

While the City does not have dedicated staff for public outreach, GIS, or grant management, these functions are addressed through shared responsibilities across departments and through coordination with regional partners such as Napa County, which provides GIS support. This shared staffing approach effectively supports current mitigation activities but represents an opportunity for enhancement as hazard mitigation, climate adaptation, and grant funding efforts expand.

Warning Systems & Services
The City of Calistoga has strong warning and emergency communication capabilities to alert residents, businesses, and visitors of hazardous conditions and emergency situations. The city utilizes the Alert Napa County emergency notification system as its primary platform for disseminating time-sensitive warnings related to natural hazards, evacuations, sheltering, and public safety incidents. These alerts are also supported by vehicle and stationary sirens located throughout the city and surrounding areas.

Emergency information is also communicated through city and partner social media channels, which provide rapid updates and situational awareness during evolving incidents. These electronic communication methods are supplemented by non-electronic outreach, including door-to-door notifications when necessary, and emergency vehicle sirens used by police and fire agencies to warn the public in affected areas.

This multi-channel approach helps ensure redundancy and increases the likelihood that critical information reaches residents with varying access to technology or communication needs. Warning systems support response to a range of hazards, including flooding, wildfire, earthquakes, extreme weather, and power shutoff events.

In addition, the city’s 70-acre fairgrounds property serves as an incident command post for the city, CAL FIRE, and other emergency services during large incidents, such as the Pickett and Tubbs Fires in the past decade. The fairgrounds can also serve as a temporary evacuation location, including for adjacent communities and counties when needed. The city is evaluating opportunities to formalize the fairgrounds as its Emergency Operations Center with emergency sheltering facilities.

Fiscal
The City of Calistoga has moderate to strong fiscal capacity to support hazard mitigation through a combination of local revenues, fees, grants, and long-term financing tools. These funding mechanisms support infrastructure maintenance, capital improvements, and implementation of hazard mitigation measures identified in city plans and programs.

The City collects utility fees for water, recycled water, and sewer services, which help fund infrastructure upgrades that support drought resilience, flood protection, and system reliability. System development and impact fees are also a key funding source and are assessed for traffic, housing, water and wastewater CAL OES SUBMITTAL - JUNE 2026
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capacity, parks and recreation, civic facilities, General Plan implementation, and fire district mitigation.

These fees help ensure that new development contributes to infrastructure needed to safely accommodate growth.

Calistoga has the authority to use general obligation bonds and special tax or revenue bonds to finance large capital projects, providing flexibility to fund hazard mitigation–related infrastructure improvements when voter approval or project-specific revenues are available. The city also adopts a Capital Improvement Program (CIP) tied to the annual budget, which prioritizes investments in infrastructure that supports public safety and resilience.

Additional funding sources include Community Development Block Grants (CDBG), which can be used for hazard-related housing rehabilitation and infrastructure improvements, particularly for vulnerable populations. While special-purpose taxes and benefit assessments are not consistently used, the City has the authority to pursue voter-approved tax measures for specific purposes, such as public safety or infrastructure, representing a future opportunity to expand mitigation funding.

Education & Outreach
The City of Calistoga has strong education and outreach capabilities that support public awareness, preparedness, and risk reduction for natural hazards. The city maintains a dedicated emergency preparedness webpage, Alert Napa County, which centralizes information on alerts, evacuations, flooding, wildfire, earthquakes, power shutoffs, and other hazards. This resource serves as the primary hub for hazard-related public information.

The city actively uses social media platforms, including City websites, Facebook, and YouTube, to disseminate emergency information, preparedness messaging, and real-time updates during incidents.

These digital tools are complemented by participation in annual public safety and preparedness events, such as the Great California ShakeOut and Ready Napa County initiatives.

Calistoga supports community-based preparedness through the Community Emergency Response Team (CERT) program and partnerships with regional organizations, including local Fire Safe Councils and the Napa Communities Firewise Foundation. The city also collaborates with the Napa County Resource Conservation District, which provides outreach related to wildfire, drought, and other environmental hazards.

City staff are available to respond to public inquiries and provide technical assistance related to hazard preparedness, floodplain regulations, and development standards through phone, email, and web-based requests. While hazard information is primarily disseminated online, printed materials and library-based resources are used on a limited basis, representing an opportunity for expanded outreach to residents with limited digital access.

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ASSESSMENT LEGEND
HMP Integration
Status Current Mitigation Use Future Opportunity
Currently in use or present. Used widely for mitigation. Opportunity to expand and integrate. (Sort of) Seldomly used or limited
presence.

Limited use in mitigation
planning.

Limited opportunity to expand and
integrate.
(No) Not present or available. Not used in mitigation planning. No opportunity to expand or integrate.

Table 2-15: City of Calistoga Capabilities and Opportunities Assessment HMP Integration
Resource Status
Current
Mitigation
Use
Future
Opportunity Notes / Additional Detail
Planning and Regulatory
Capabilities
Construction and Future
Development Regulations
Building Codes
Green Green Green
California Building Code (California Code of
Regulations, Title 24) adopted and amended under
Title 15
BCEGS Rating 0 0 0
Public Protection (ISO Class) Green Green Green 3/3Y
Hazard-Related Development
Standards
Green Green Green
Titles 15, 16, 17, 18, and 19 cover development
standards for fire, climate change, seismic,
geologic, flood, and drought hazards; Title 15 covers
fire code amendments and enhancement; FHSZ
ordinance adopted
Zoning Ordinance Green Green Green Title 17
Hazard-Specific Ordinance
Green Green Green Titles 18 and 19 cover regulations for flood, geologic, and other hazards
Growth Management Ordinance
Green Green Green
General Plan (Land Use, Infrastructure, Housing,
and other elements) and Chapter 19.02, Growth
Management System
Hazard Reduction Programs
(Annually Conducted)
Capital Improvements Program
(CIP) or Plan
Green Green Green
Program forecasts, details, and tracks progress on
facility and infrastructure improvements (e.g.,
parks, stormwater, streets, water, and wastewater)
Erosion/Sediment Control
Program Green Green Green
Title 19 includes regulations for stormwater runoff
and pollution control, watercourses, slopes, and
erosion hazards
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HMP Integration
Resource Status
Current
Mitigation
Use
Future
Opportunity Notes / Additional Detail
Hazard-Related Public Outreach
Program Green Green Green City Manager, Office of Emergency Services Urban Water Management Plan
Green Green Green
Title 19 includes regulations for stormwater runoff
and pollution control, watercourses, and water
quality and quantity conservation
Stormwater Management
Program (Annual Inspections) Green Green Green
Title 19 covers stormwater runoff and pollution
control and Public Works Dept manages
stormwater
Seismic Safety Program (Nonstructural) Green Green Green City Manager, Office of Emergency Services; Public Works
Earthquake Modernization Plan
(Building Safety)
Yellow Yellow Green
General Plan Public Safety Element prescribes
actions to address remaining URM and other
seismically unsafe buildings through targeted
outreach and enforcement of the California
Building Code
Hazard Plans
General Plan Safety Element
Green Green Green
2020 Public Safety Element covers geologic,
seismic, flood, dam failure, tsunami/seiche, and
wildfire hazards (needs update)
Site Plan Review Requirements
Green Green Green Title 17 review procedures for Use Permits and Design Review
General Plan Environmental
Justice Element Yellow Yellow Yellow No formal Element, but incorporated in various elements of the 2020 General Plan
Community Wildfire Protection
Plan (CWPP) Green Green Green 2021 Napa County CWPP
Economic Development Plan
Green Green Green 2020 General Plan Economic Development Element Floodplain Management Plan
Green Green Green 2020 Public Safety and Housing Elements, and Title 18, Floodplain Management regulations
Stormwater Management Plan
Green Green Green
Title 19 covers stormwater runoff and pollution
control and Public Works Dept manages
stormwater
Emergency Operations Plan
Green Green Green 2017 Napa County EOP, City Annex; updated to 2024 EOP, working on annex update
Climate Action Plan
Yellow Yellow Green
2014 Climate Action Plan and 2020 General Plan
Open Space and Conservation Element; update
opportunity
Climate Vulnerability
Assessment Orange Orange Green
No formal assessment, but incorporated in 2014
Climate Action Plan and 2020 General Plan Open
Space and Conservation Element
Urban Greening Plan
Green Green Green
2014 Climate Action Plan, 2020 General Plan Open
Space and Conservation Element, and Chapter 19.01,
Trees
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HMP Integration
Resource Status
Current
Mitigation
Use
Future
Opportunity Notes / Additional Detail
Ground Water Management
Planning / Plans Green Green Green
Maintained by Napa County Groundwater
Sustainability Agency; Chapter 19.08, Conservation
Regulations
National Flood Protection
Program (NFIP)
Floodplain Management
Regulations Green Green Green Title 18, Floodplain Management regulations Flood Insurance Education and
Technical Assist. Green Green Green Available through Public Works Dept, Engineering Services
Flood Insurance Study Green Green Green FEMA FIS 06055CV000C effective 2016 Elevation Certificates
Green Green Green Elevation Certificates managed by Public Works Dept, Engineering Services
Flood Hazard Mapping / ReMapping Green Green Green FEMA FIRMs effective 2008 and 2016 Community Rating System (CRS) Orange Orange Yellow Does not currently participate Administrative and Technical
Community Planning and
Development Services
Community Planner Green Green Green Planning & Building Dept, Planning Division Planner/Engineer (Land
Development) Green Green Green Planning & Building Dept, Planning Division, and Public Works Dept, Engineering Services
Engineer/Professional
(Construction)
Green Green Green Public Works Dept, Engineering Services Planner/Engineer/Scientist
(Natural Hazards) Yellow Yellow Green Shared role within Public Works Dept, Engineering Services
Transportation Planner Green Green Green Public Works Dept, Public Transit Services Resiliency Planner Yellow Yellow Green Shared role within Planning & Building Dept, Planning Division
Building Code Official (Full time
or Augmented) Green Green Green Planning & Building Dept, Building Division Floodplain Administrator Green Green Green Planning & Building Dept Director Fire Marshal Green Green Green Fire Dept
Dedicated Public Outreach
Personnel Yellow Yellow Green No dedicated staff; shared across departments; future opportunity
GIS Specialist and Capability Orange Orange Green No dedicated staff; limited capabilities Emergency Manager Green Green Green City Manager, Office of Emergency Services Dedicated Grant Manager, Writer,
or Specialist Yellow Yellow Green No dedicated staff; shared across departments; future opportunity
Other N/A N/A N/A
Warning Systems/Services
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HMP Integration
Resource Status
Current
Mitigation
Use
Future
Opportunity Notes / Additional Detail
General
Green Green Green
Alert Napa County system; Hi-Lo emergency
vehicle sirens; emergency alert sirens; Channel 27;
AM 1670
Flood
Green Green Green
Alert Napa County system; Hi-Lo emergency
vehicle sirens; emergency alert sirens; Channel 27;
AM 1670
Tornado
Green Green Green
Alert Napa County system; Hi-Lo emergency
vehicle sirens; emergency alert sirens; Channel 27;
AM 1670
Wildfire
Green Green Green
Alert Napa County system; Hi-Lo emergency
vehicle sirens; emergency alert sirens; Channel 27;
AM 1670
Geological Hazards
Green Green Green
Alert Napa County system; Hi-Lo emergency
vehicle sirens; emergency alert sirens; Channel 27;
AM 1670
Fiscal Capabilities
Financial Resources for
Hazard Mitigation
Levy Taxes for Specific Purposes
Yellow Yellow Yellow
Not consistently applied, but can place special tax
measures on ballot for specific purposes (e.g., sales
tax for public safety)
Utilities Fees Green Green Green Water and wastewater fees Benefit assessments Orange Orange Yellow Not currently in use; future opportunity Community Development Block
Grants Yellow Yellow Green Recieved via HUD; can support hazard-related housing rehabilitation and infrastructure
System Development Fee
Green Green Green Development impact/system fees collected for City infrastructure
General Obligation Bonds to
Incur Debt Green Green Green General obligation bonds are available financing tools
Special Tax Bonds to Incur Debt
Green Green Green Special tax/revenue bonds are authorized for specific projects
Withheld Spending in HazardProne Areas Green Green Green General Plan policies restrict development in hazard-prone areas
Stormwater Service Fees Orange Orange Yellow Not currently in use; future opportunity Capital Improvement Project
Funding Green Green Green CIP is adopted; tied to annual budget and GP implementation
Education / Outreach
Capabilities
Education/Outreach
Resources
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HMP Integration
Resource Status
Current
Mitigation
Use
Future
Opportunity Notes / Additional Detail
Website Dedicated to Hazard
Topics Green Green Green Maintains Disaster Preparedness webpage Dedicated Social Media Green Green Green Active Facebook and YouTube pages Local Citizen Groups That
Communicate Hazard Risks Green Green Green Informal local groups provide hazard information; CERT; Calistoga Fire Safe Council
Hazard Info. Avail. at Library/
Planning Desk Yellow Yellow Green Hazard info available via City website and partner websites
Annual Public Safety Events
Green Green Green Participates in Earthquake ShakeOut, Ready Napa County, and other regular events
Ability to Field Public Tech.

Assistance Requests Green Green Green
Staff respond to inquiries via phone, email, and web
forms; department-specific technical assistance
available
Public Safety Newsletters or
Printed Outreach Yellow Yellow Green Not used consistently; mostly web-based Community Emergency
Response Team (CERT) Green Green Green Calistoga CERT
Fire Safe Councils
Green Green Green Calistoga Fire Safe Council and others through Napa Communities Firesafe Foundation
Firewise Green Green Green Firewise USA participant
StormReady Orange Orange Green Not StormReady designated Resource Conservation Districts
Green Green Green
Napa County RCD provides outreach on wildfire,
drought, and other hazard topics; City participates
through partnerships
Other N/A N/A N/A
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2.6.2 City of Calistoga Mitigation Action Plan
Calistoga’s mitigation
actions were developed
through a collaborative
process informed by the
updated risk assessment,
local priorities, and
extensive stakeholder
engagement. As part of
this 2026 MJHMP update,
the city reviewed
mitigation actions from
its prior Local Hazard
Mitigation Plan to
determine which actions
to carry forward, which
to consolidate, and
where entirely new
strategies were required.

This careful evaluation
ensured that the updated
action plan builds upon
past commitments while also responding to current risks and future challenges.

The plan addresses Calistoga’s most significant hazards, including wildfire, earthquake, flood, slope failure, drought, dam failure, and extreme weather. Each mitigation action is designed to align with FEMA’s hazard mitigation guidance and the requirements of the Disaster Mitigation Act of 2000. Where appropriate, overlapping or redundant actions were consolidated into broader, more comprehensive strategies that improve clarity, increase feasibility, and strengthen regional coordination.

The mitigation action prioritization method used by all participating jurisdictions is described in Volume 1, Section 4. Each action specific to Calistoga is documented in Table 2-16, which identifies the responsible department, implementation timeframe, potential funding sources, and resources required to complete the action. Each action is also assigned a unique alphanumeric identifier (see Figure 2-18) that links the strategy to its associated hazard and supports consistent monitoring and reporting.

Calistoga’s approach recognizes that some hazards are most effectively addressed through regional efforts.

Flood protection, drought resilience, and wildfire risk reduction often extend beyond the city’s boundaries and require collaboration with county, regional, and state partners. By aligning local actions with regional strategies, Calistoga helps to consolidate resources, maximize funding opportunities, and ensure that mitigation projects achieve the greatest benefit for the Napa Valley, and the wider Napa County community.

Figure 2-18: Mitigation Action Number Key
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Collectively, these mitigation actions provide a roadmap for reducing hazard risk, protecting vulnerable populations, and strengthening the long-term resilience of Calistoga.

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Table 2-16: City of Calistoga Mitigation Action Plan
Mitigation No. Hazard
Type
SubHazardMitigation
Type
Year Primary
Agency
Title Description Responsible
Party
Estimated
Cost
Estimated
Benefit
Time
Frame
HMA
Activity
Type
Potential Grant
Source
Priority Related Problem Statements
ma-AH-CL-3 All Hazard ES -
Emergency
Services , SP -
Structural
Projects
2020 City of
Calistoga
Microgrid &
Backup Power
Expansion
Program
Expand Calistoga’s existing microgrid and
backup-power capacity for critical facilities (e.g.,
EOC, Police/Fire Station, WWTP) to ensure
energy reliability during outages and PSPS
events.

Public Works
Department
High High 3-5 Years Project HMGP / BRIC ,
General Fund
High ps-WF-CL-184, ps-EH-CL-328,
ps-WF-CL-317, ps-WF-CL-318
ma-AH-CL-87 All Hazard SP - Structural
Projects
2013 City of
Calistoga
Retrofit &
Replace
Critical
Infrastructure
Replace and upgrade aging and vulnerable
water, sewer, recycle, and stormwater
infrastructure to increase resilience against
wildfire, earthquake, severe weather, flood, and
drought. Improve water delivery system to
provide sufficient fire flows and pressures,
including additional system loops. Improve or
replace brittle, undersized, and leaking lines at
risk from hazard events.

Public Works
Department
High High 5-10 Years Project HMGP / BRIC ,

CDBG DRI ,
EMPG , General
Fund , CalFIRE
Extreme ps-WF-CL-179, ps-WF-CL-318,
ps-SW-CL-147, ps-SW-CL-145,
ps-SW-CL-125, ps-FL-CL-111,
ps-EQ-CL-67, ps-DR-CL-321
ma-AH-CL-218 All Hazard PPRO -
Property
Protection , ES
- Emergency
Services
2026 City of
Calistoga
Expand
Emergency
Sheltering
Network
Identify additional emergency shelter locations
for a range of hazard events and ensure all
primary locations are accessible and have
sufficient back up power and HVAC systems
(e.g., Tubbs, Butler, Civic Center/Fairgrounds).

Office of
Emergency
Services
Medium High 3-5 Years Project HMGP / BRIC ,
General Fund
Medium ps-CC-CL-13, ps-FL-CL-108,
ps-EQ-CL-82, ps-EH-CL-326,
ps-EH-CL-327, ps-EH-CL-328,
ps-SW-CL-145, ps-SW-CL-323,
ps-WF-CL-179, ps-WF-CL-183,
ps-WF-CL-317
ma-AH-CL-247 All Hazard ES -
Emergency
Services
2026 City of
Calistoga
New
Emergency
Operations
Center
Develop a new Emergency Operations Center
(EOC) at the Calistoga Fairgrounds to serve as
City and CalFire Incident Command Post and as
an evacuation location.

Office of
Emergency
Services
High Medium 3-5 Years Project HMGP / BRIC ,
EMPG , General
Fund
High
ma-CC-CL-219 Climate
Change
PRV -
Prevention
2026 City of
Calistoga
Climate
Adaptation &
Resilience
Plan Update
Update the 2014 Climate Action Plan to include a
vulnerability assessment as well as mitigation
and adaptation strategies for climate-driven
hazards.

Planning &
Building
Department
Medium Low 3-5 Years Project HMGP / BRIC ,
General Fund
Medium ps-DR-CL-321, ps-FL-CL-319,
ps-CC-CL-325, ps-CC-CL-324,
ps-CC-CL-15, ps-CC-CL-13, psEH-CL-326
ma-DR-CL-22 Drought SP - Structural
Projects
2020 City of
Calistoga
Water Supply
Contingency &
Storage
Expansion
Implement water supply contingency projects,
such as increasing water supply delivery,
storage, and treatment capacity at Kimball
Reservoir and Water Treatment Plant, to
improve resilience during drought years.

Public Works
Department
High High 5-10 Years Project HMGP / BRIC ,
General Fund
Medium ps-DR-CL-47, ps-DR-CL-321,
ps-DR-CL-320, ps-DR-CL-46,
ps-DR-CL-45
ma-DR-CL-220 Drought PE&A - Public
Education &
Awareness
2026 City of
Calistoga
Water
Conservation
Outreach
Program
Expand outreach on water conservation
practices, drought-resilient landscaping, and
plumbing fixture upgrade resources for
residents and businesses.

City Manager's
Office
Low Medium 1-3 Years Capacity /
Capability
Building

HMGP / BRIC ,
General Fund
High ps-DR-CL-321, ps-DR-CL-320,
ps-DR-CL-45
ma-EQ-CL-34 Earthquake PPRO -
Property
Protection
2020 City of
Calistoga
Critical
Facilities
Seismic
Retrofits
Assess and retrofit critical facilities, such as the
Tubbs and Butler buildings and the fire station,
to meet current seismic standards.

Planning &
Building
Department,
Public Works
Department
High High 5-10 Years Project HMGP / BRIC ,
General Fund
High ps-EQ-CL-66, ps-EQ-CL-67, psEQ-CL-81, ps-EQ-CL-322 ma-EQ-CL-35 Earthquake PE&A - Public
Education &
Awareness
2020 City of
Calistoga
Earthquake
Preparedness
Outreach
Program
Develop a comprehensive public education
program on earthquake risk, household
readiness, and retrofit resources.

Planning &
Building
Department,
Office of
Emergency
Services
Low Medium 1-3 Years Capacity /
Capability
Building

HMGP / BRIC ,
General Fund
High ps-EQ-CL-66, ps-EQ-CL-82, psEQ-CL-322
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Mitigation No. Hazard
Type
SubHazardMitigation
Type
Year Primary
Agency
Title Description Responsible
Party
Estimated
Cost
Estimated
Benefit
Time
Frame
HMA
Activity
Type
Potential Grant
Source
Priority Related Problem Statements
ma-FL-CL-48 Flood NRP - Natural
Resource
Protection , SP
- Structural
Projects
2013 City of
Calistoga
Stormwater
Drainage &
Flood
Mitigation
Improvements
Implement localized flood reduction projects
and improve stormwater system capacity.

Implement drainage improvements at public
facilities and in frequently impacted areas to
reduce localized flooding and improve water
quality, including through installing back-up
power for critical system components,
increasing maintenance capacity (e.g., more
street sweepers), and nature-based solutions
such as rain gardens, permeable pavement, and
bioswale retrofits.

Public Works
Department
High High 3-5 Years Project HMGP / BRIC ,
FMA , General
Fund
High ps-FL-CL-108, ps-FL-CL-109,
ps-FL-CL-111
ma-SW-CL-79 Severe
Weather
PRV -
Prevention ,
NRP - Natural
Resource
Protection , SP
- Structural
Projects
2020 City of
Calistoga
Utility & Tree
Hardening
Program
Establish standards and maintenance cycles for
tree trimming and line clearance in
collaboration with PG&E.

Public Works
Department
Medium High 3-5 Years Capacity /
Capability
Building

HMGP / BRIC ,
General Fund
Medium ps-SW-CL-147, ps-SW-CL-148,
ps-SW-CL-323
ma-WF-CL-11 Wildfire NRP - Natural
Resource
Protection , SP
- Structural
Projects
2020 City of
Calistoga
Defensible
Space & Fuel
Break
Enhancement
In coordination with the CWPP and Fire Safe
Council, implement fuel-reduction and
defensible-space projects in WUI areas and near
critical facilities, and establish an ongoing
maintenance program.

Fire Department Medium High 1-3 Years Capacity /
Capability
Building

HMGP / BRIC ,
General Fund ,
CalFIRE
High ps-CC-CL-13, ps-CC-CL-15
ma-WF-CL-89 Wildfire PE&A - Public
Education &
Awareness
2013 City of
Calistoga
Wildfire
Preparedness
& Prevention
Outreach
Program
Establish an outreach program focused on
wildfire preparedness and prevention, including
addressing human causes of ignition,
evacuation preparedness, home mitigation
methods (structure hardening, defensible space),
and available mitigation resources and
incentives.

Fire Department,
Office of
Emergency
Services
Low Medium 1-3 Years Capacity /
Capability
Building

HMGP / BRIC ,
General Fund ,
CalFIRE
High ps-WF-CL-179
ma-WF-CL-221 Wildfire PRV -
Prevention
2026 City of
Calistoga
WUI Code
Enforcement
Program
Develop and implement a WUI code
enforcement program that increases inspection
capacity, improves enforcement mechanisms,
and helps to educate property owners of risks,
mitigation measures, and available resources,
with a focus on those neighborhoods and
properties most at risk and with vulnerable
populations (e.g., seniors in FHSZs).

Fire Department Medium High 1-3 Years Capacity /
Capability
Building

HMGP / BRIC ,
General Fund ,
CalFIRE
High ps-WF-CL-184, ps-WF-CL-183,
ps-WF-CL-179
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2.6.3 Status of Previous Mitigation Actions
In 2020, the City of Calistoga adopted its previous FEMA-approved HMP. This 2026 MJHMP represents a comprehensive update from that previous plan, as discussed in Volume 1, Section 1.5. Table 2-17 provides status updates for all of the previous mitigation actions in the City of Calistoga HMP, from which many of the mitigation actions in Table 2-16 were sourced and revised.

Table 2-17: City of Calistoga Status of Previous Mitigation Actions Mitigation
No.

Hazard
Type Status Year Primary Agency Title/Description Reason Completed/ Cancelled ma-AH-CL-3 All Hazard Ongoing 2020 City of Calistoga Microgrid & Backup Power Expansion Program Revised
ma-WF-CL87 Wildfire Ongoing 2013 City of Calistoga Retrofit & Replace Critical Infrastructure Revised
ma-DR-CL22 Drought Ongoing 2020 City of Calistoga Water Supply Contingency & Storage Expansion Revised
ma-EQ-CL34 Earthquake Ongoing 2020 City of Calistoga Critical Facilities Seismic Retrofits Revised
ma-EQ-CL-35 Earthquake Ongoing 2020 City of Calistoga Earthquake Preparedness Outreach Program Revised
ma-FL-CL-48 Flood Ongoing 2013 City of Calistoga Stormwater Drainage & Flood Mitigation Improvements Revised
ma-SW-CL79Severe
Weather Ongoing 2020 City of Calistoga Utility & Tree Hardening Program Revised ma-CC-CL-11 Climate
Change Ongoing 2020 City of Calistoga Defensible Space & Fuel Break Enhancement Revised ma-WF-CL89 Wildfire Ongoing 2013 City of Calistoga
Wildfire Preparedness &
Prevention Outreach
Program
Revised
ma-DR-CL-21 Drought Completed 2020 City of Calistoga
During Drought conditions
increase fuel reduction in
parks and open space areas.

Adopted City policy
ma-FL-CL-50 Flood Completed 2020 City of Calistoga
Remap the floodplain and
enhance flood protection for
critical facilities north of
Lincoln Avenue.

New FEMA flood study
completed 2025
ma-WF-CL88 Wildfire Completed 2013 City of Calistoga
Revise the General Plan
Safety Element with lessons
learned from to include new
information from HMP and
Fire-wise programs and
analysis.

General Plan Safety Element
update completed in 2020
ma-CC-CL-12 Climate
Change Cancelled 2020 City of Calistoga
Map high-risk areas and
implement fuel reduction
projects.

Duplicate of CL-08-2020 (now
revised)
ma-FL-CL-49 Flood Cancelled 2013 City of Calistoga
Regularly inspect and
maintain stormwater inlets
and outfalls for debris,
blockages, and damage.

Ongoing baseline mitigation
requirement
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Mitigation
No.

Hazard
Type Status Year Primary Agency Title/Description Reason Completed/ Cancelled ma-SW-CL80Severe
Weather Cancelled 2020 City of Calistoga
Identify schools designated
by the Red Cross as
emergency shelters and
ensure they have backup
power. Verify that all City and
school shelters meet current
codes, are in non-flood areas,
and are equipped with
standby power for public use
during emergencies.

Revised to for all hazard (maAH-CL-218)
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Section 3. City of Napa
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Napa County
2026 Multi-Jurisdictional Hazard Mitigation Plan Update City of Napa (CN)
Municipal Annex
Adoption Record ........................................................................................................................................ 3-7 Section 3. City of Napa ............................................................................................................................. 3-9

3.1 Scope & Purpose .......................................................................................................................................................................................3-9

3.2 Jurisdictional Setting ............................................................................................................................................................................3-9 Geography & Climate............................................................................................................................................................................................3-10 Demographics & Vulnerable Populations....................................................................................................................................................3-12 Economy .................................................................................................................................................................................................................. 3-28 Growth Trends & Future Development........................................................................................................................................................ 3-28

3.3 Planning Process..................................................................................................................................................................................3-29 Public Input & Draft Review .............................................................................................................................................................................. 3-34

3.4 What’s New .............................................................................................................................................................................................3-34 Mitigation Activities............................................................................................................................................................................................ 3-34 Successes Since 2021...........................................................................................................................................................................................3-35

3.5 Risk Assessment ..................................................................................................................................................................................3-38 Hazard Screening & Prioritization ................................................................................................................................................................. 3-38 Vulnerability to Specific Hazards.................................................................................................................................................................. 3-42 Climate Change Impacts & Vulnerable Populations.............................................................................................................................. 3-78 Hazard Problem Statements............................................................................................................................................................................ 3-79

3.6 Mitigation Strategy..............................................................................................................................................................................3-83 Capabilities & Opportunities............................................................................................................................................................................. 3-84 City of Napa Mitigation Action Plan............................................................................................................................................................. 3-97 Status of Previous Mitigation Actions............................................................................................................................................................ 3-1 CAL OES SUBMITTAL - JUNE 2026
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List of Figures
Figure 3-1: City of Napa Geographic Overview Map....................................................................................................................... 3-11 Figure 3-2: City of Napa Median Household Income Map ...........................................................................................................3-15 Figure 3-3: City of Napa Poverty Status Map.....................................................................................................................................3-16 Figure 3-4: City of Napa Housing Occupancy Map.........................................................................................................................3-17 Figure 3-5: City of Napa Dependent Age Groups Map ...................................................................................................................3-21 Figure 3-6: City of Napa Disabled Elderly Map ................................................................................................................................3-22 Figure 3-7: City of Napa Race and Ethnicity Map ..........................................................................................................................3-24 Figure 3-8: City of Napa Spanish-Speaking Households Map................................................................................................... 3-25 Figure 3-9: City of Napa CDC Social Vulnerability Index Map ..................................................................................................3-27 Figure 3-10: City of Napa Risk Assessment Matrix........................................................................................................................3-40 Figure 3-11: Exposure Summary- City of Napa Wildfire Risk ....................................................................................................3-44 Figure 3-12: Exposure Summary – City of Napa Dam Inundation Zone ...............................................................................3-46 Figure 3-13: City of Napa Flood Risk (FEMA and DWR Awareness Zones) ..........................................................................3-48 Figure 3-14: Exposure Summary – City of Napa Flood Risk (FEMA Zones) ........................................................................3-49 Figure 3-15: City of Napa Repetitive Loss Areas.............................................................................................................................. 3-53 Figure 3-16: Stonecrest RL Area............................................................................................................................................................. 3-56 Figure 3-17: RiverPointe RL Area........................................................................................................................................................... 3-57 Figure 3-18: Soscol North RL Area ........................................................................................................................................................ 3-58 Figure 3-19: Oxbow West RL Area ......................................................................................................................................................... 3-59 Figure 3-20: Oxbow East RL Area..........................................................................................................................................................3-60 Figure 3-21: Soscol South RL Area .........................................................................................................................................................3-61 Figure 3-22: Exposure Summary – City of Napa Earthquake Risk (M7.1 Hunting Creek–Berryessa)......................3-67 Figure 3-23: Exposure Summary – City of Napa Earthquake Risk (M6.7 West Napa).....................................................3-68 Figure 3-24: Exposure Summary – City of Napa Liquefaction Risk .......................................................................................3-69 Figure 3-25: Drought Severity Timeline 2000-2026.......................................................................................................................3-72 Figure 3-26: Mitigation Action Number Key.....................................................................................................................................3-97 List of Tables
Table 3-1: City of Napa Population and Households.......................................................................................................................3-12 Table 3-2: City of Napa Income and Poverty .....................................................................................................................................3-13 Table 3-3: City of Napa Renter- and Owner-Occupied Housing................................................................................................3-14 Table 3-4: City of Napa Households with Seniors ...........................................................................................................................3-18 Table 3-5: City of Napa Households with Children.........................................................................................................................3-19 Table 3-6: City of Napa Population with Disabilities and Access to Transportation .......................................................3-20 Table 3-7: City of Napa Household Languages ................................................................................................................................ 3-23 Table 3-8: City of Napa Planning Team and Steering Group Members.................................................................................3-30 Table 3-9: City of Napa Planning Team Meetings.......................................................................................................................... 3-33 Table 3-10: City of Napa Document Review of Potential Hazards ...........................................................................................3-39 Table 3-11: City of Napa Hazards Prioritization Summary...........................................................................................................3-41 CAL OES SUBMITTAL - JUNE 2026
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Table 3-12: City of Napa National Flood Insurance Program Information...........................................................................3-50 Table 3-13: Summary of Relevant Discharges in Napa County.................................................................................................3-63 Table 3-14: Drought Classifications and Impacts ...........................................................................................................................3-70 Table 3-15: Cal-Adapt Extreme Heat Thresholds............................................................................................................................3-74 Table 3-16: City of Napa Hazard Problem Statements..................................................................................................................3-80 Table 3-17: City of Napa Capabilities and Opportunities Assessment...................................................................................3-92 Table 3-18: City of Napa Mitigation Action Plan .............................................................................................................................3-98 Table 3-19: City of Napa Status of Previous Mitigation Actions ..................................................................................................3-1 CAL OES SUBMITTAL - JUNE 2026
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Adoption Record
To comply with the Federal Disaster Mitigation Act of 2000 (DMA 2000), the City of Napa City Council has officially adopted this 2026 Napa County Multi-Jurisdictional Hazard Mitigation Plan, including Volume 1 in its entirety as well as this Volume 2 municipal annex. The adoption of the MJHMP recognizes the city’s commitment to reducing the impacts of natural hazards within their jurisdiction and across Napa County.

A copy of the City of Napa’s adoption record is provided on the following pages.

INSERT City of Napa adoption record
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Section 3. City of Napa

3.1 Scope & Purpose
This Jurisdictional Annex for the City of Napa of the 2026 Napa County Multi-Jurisdictional Hazard Mitigation Plan (MJHMP) details the hazard mitigation planning elements specific to the city’s planning area. The annex is not intended to be a standalone document but appends to and supplements the information contained in the umbrella plan document (Volume 1). As such, all sections of the umbrella plan, including the planning process and other procedural requirements, apply to and were met by the City of Napa. This annex provides additional information specific to the city, with a focus on hazard identification and risk assessment, vulnerability assessment, problem statements, mitigation strategy, and capabilities assessment. Below are the City of Napa Points of Contact:

Primary Point of Contact Alternate Point of Contact
Zach Curren, Fire Chief
City of Napa
1600 Clay Street
Napa, CA 94559
Telephone: (707) 257-9593
Email: [email protected]
Jaina French, Community Relations & Media
Manager
City Manager’s Office, City of Napa
PO Box 660 / 955 School Street, Napa, CA 94559
Telephone (707) 258-7843
Email [email protected]

3.2 Jurisdictional Setting
The City of Napa is located in the heart of Napa County in Northern California, at the southern end of the world-renowned Napa Valley wine region approximately 50 miles north of San Francisco and accessible via State Route 29 and State Route 121. Napa is a vibrant city with a blend of historical charm and contemporary development, serving as the county seat and a central hub for government, tourism, and commerce.

Nestled along the Napa River and surrounded by vineyards and rolling hills, the City of Napa reflects its agricultural heritage while also embracing innovation in food, wine, and sustainable development. The community is known for its commitment to environmental resilience, historic preservation, and cultural vitality. Landmarks such as the Napa Riverfront, the Uptown Theatre, and historic downtown buildings illustrate the city's rich past and dynamic present.

The City of Napa spans approximately 18.1 square miles, with an average elevation of 20 feet above sea level.

Napa continues to grow steadily, with ongoing efforts in urban planning, housing development, transportation improvements, and flood mitigation projects that reflect the city’s forward-thinking approach to resilience and livability. City of Napa’s location within Napa County and the State of California are shown in Figure 3-1.

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▪ Date of Incorporation: March 23, 1872
▪ Current Population: 78,174 (United States Census Bureau, 2016-2021) ▪ Population Growth: The City has experienced an estimated a population increase of 9% between 2010 and 2021 (United States Census Bureau, 2016-2021)
Geography & Climate
The City of Napa, located in the southern portion of the Napa Valley in Northern California, is characterized by a diverse geography that includes flat valley floors, rolling hills, and riverine features. The city lies along the Napa River, which plays a central role in its hydrology and has influenced both development patterns and floodplain management. Napa’s terrain is largely shaped by alluvial deposits from nearby hills and mountains, consisting of fertile soils that have historically supported the region’s agricultural economy, particularly viticulture.

To the east and west of the city, the landscape transitions into low mountain ranges and foothills, which form part of the Coast Ranges and contribute to microclimates within the valley. These geologic formations include sedimentary rocks, volcanic deposits, and clay-rich soils, all of which influence local drainage, vegetation, and land use suitability.

Napa’s climate is Mediterranean, with warm to hot, dry summers and mild, wet winters. Average high temperatures in the summer can reach the 80s to low 90s degrees Fahrenheit (°F), while winter lows typically range from the upper 30s to mid-50s°F. Most precipitation falls between November and March, with minimal rainfall during the summer months. Snowfall is virtually nonexistent due to the city's low elevation of approximately 20 feet above sea level.

Local wind patterns are generally light but can be influenced by marine air flow from San Pablo Bay to the south, especially during summer evenings, contributing to the region’s favorable growing conditions. While Napa’s geography and climate support a thriving wine and tourism industry, they also pose hazard risks such as flooding, drought, and wildfire in surrounding areas.

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Figure 3-1: City of Napa Geographic Overview Map
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Demographics & Vulnerable Populations
This section describes the demographic characteristics of the City of Napa to guide hazard mitigation planning efforts. Natural disasters affect communities both physically and socially, with demographic composition playing a central role in determining how impacts are distributed, particularly among vulnerable groups facing greater challenges in preparedness, response, and recovery. Understanding the area's social and economic landscape also helps assess potential social costs from infrastructure damage, including housing, industry, public facilities, essential services, and transportation.

Exploring local demographic data may help to identify groups and geographic areas with specific vulnerability to hazard events. In the context of all-hazards preparedness and response planning, at-risk individuals (often used interchangeably with “vulnerable populations”) are defined federally as “children, pregnant women, senior citizens, and other individuals who have access or functional needs in the event of a public health emergency.” (42 U.S.C. § 2802(b)(4)(B) (2019)) These populations may include, but are not limited to, individuals who are economically disadvantaged, living with disabilities, dependent on caregivers, from historically marginalized communities, have limited English proficiency or are nonEnglish speaking, lack access to transportation, are experiencing homelessness, or have chronic medical conditions.

Certain populations face greater risk following a natural hazard event due to age, economic mobility, physical disability, geographic location, or a combination of factors. Vulnerability in the face of a hazard event is not a fixed characteristic; the same individual may be at risk for some hazards but not at risk for others. Planning for vulnerable populations in the context of hazard mitigation can help communities to prioritize limited resources where they will be the most effective. Refer to Volume 1, Section 1.4.3, for a more in-depth discussion of planning for vulnerable populations, at-risk individuals with access and functional needs, and environmental justice.

The total population, total number of households, and average household size of the City of Napa are presented in Table 3-1, compared to the other municipalities and Napa County. As shown in the table, Napa is the largest city in Napa County.

Table 3-1: City of Napa Population and Households
Area Total Population Total Households (HH) Average HH Size Napa County 137,384 55,588 2.40
City of Napa 79,233 31,666 2.47
City of American Canyon 21,669 5,924 3.64
City of Calistoga 5,191 2,330 2.20
City of St. Helena 5,426 2,963 1.81
Town of Yountville 3,397 1,824 1.45
Source: ACS 5-Year, 2017-2022
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3.2.2.1 Income & Housing
Economic mobility is one of the most important predictors of natural hazard vulnerability. Low-income residents are more likely to occupy housing which is inadequately maintained or otherwise poorly built to withstand extreme events. For example, mobile or modular homes are more susceptible to damage in earthquakes and floods than other types of residences and are less likely to contain air conditioning units to cope with high heat events. In urban areas, low-income residents are more likely to occupy older homes and apartment complexes with unreinforced masonry, which is particularly susceptible to seismic damage.

Low-income households and communities face disproportionate financial burden from costs associated with disaster preparedness, response, and recovery. Disasters create unexpected expenses which may serve as “tipping points” for families and individuals living on the edge of poverty or homelessness. Recovery costs may be higher for those without resources to conduct hazard mitigation activities ahead of time. Families and individuals who lack access to transportation may be unable to evacuate ahead of an emergency. (Krause & Reeves, 2017)
Low-income residents and renters are also less likely to purchase insurance, meaning that those with the most to lose during an event are also the least prepared to deal with potential losses. Major hurricane events in recent history such as Harvey, Irma, and Katrina all demonstrate that low-income or historically marginalized communities face increased vulnerability to hazard events and struggle the most to recover.

Median household income in the City of Napa is just over $100,000 annually with an overall poverty rate of around 8%. By comparison, median income and poverty rates for Napa County were nearly $106,000 and 8%, respectively; refer to Table 3-2. Median income and poverty rates are also shown on the block group level in Figure 3-2 and Figure 3-3.

Table 3-2: City of Napa Income and Poverty
Area Median Income Poverty Rate
Napa County $105,809 7.9%
City of Napa $100,273 8.1%
City of American Canyon $122,694 7.4%
City of Calistoga $96,667 5.4%
City of St. Helena $135,781 5.7%
Town of Yountville $75,134 10.6%
Source: ACS 5-Year, 2017-2022
Renters are also more vulnerable to natural hazards, as they are less likely to take out property insurance and the decision to make major structural improvements typically lies with the property owner. Federal disaster recovery services can exacerbate inequality between renters and homeowners; payout amounts are significantly higher for homeowners applying through FEMA’s Individual Assistance (IA) program; from 1999 to 2013 U.S. homeowners saw their wealth increase with local hazard damages, whereas renters’ wealth decreased. (Howell, Junia; Elliot, James, 2019)
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Approximately 40% of occupied housing units in the City of Napa are renters, compared to approximately 35% for Napa County as a whole; refer to Table 3-3. Housing occupancy are also shown on the block group level in Figure 3-4.

Table 3-3: City of Napa Renter- and Owner-Occupied Housing Jurisdiction # Occupied
Housing Units
# Renter
Occupied % Renter Occupied # Owner Occupied
% Owner
Occupied
Napa County 49,738 17,676 35.5% 32,062 64.5%
City of Napa 26,978 10,616 39.4% 16,362 60.6%
City of American Canyon 6,192 1,371 22.1% 4,821 77.9%
City of Calistoga 2,042 822 40.3% 1,220 59.7%
City of St. Helena 2,380 1,048 44% 1,332 56.0%
Town of Yountville 1,050 362 34.5% 688 65.5%
Source: ACS 5-Year, 2017-2022
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Figure 3-2: City of Napa Median Household Income Map
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Figure 3-3: City of Napa Poverty Status Map
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Figure 3-4: City of Napa Housing Occupancy Map
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3.2.2.2 Dependent & Disabled Populations
Age is a significant factor in assessing vulnerability to natural hazards. Both older adults and children are considered dependent populations due to their reliance on caregivers for safety, mobility, and support during emergency events. These populations face heightened risks during disasters such as floods, wildfires, and earthquakes, particularly when compounding factors such as poverty, disability, or social isolation are present.

In the City of Napa, approximately 32.5% of households include at least one individual over the age of 65, and over 8% of all households consist of seniors living alone. While only around 2% of senior households live below the poverty line (Table 3-4), seniors, particularly those who are low-income or socially isolated, remain among the most vulnerable populations in disaster situations. Challenges for older adults may include limited mobility, chronic health conditions, reduced digital literacy, and lack of access to real-time emergency alerts. Seniors living alone may require additional assistance during evacuations or power outages, and assisted living facilities necessitate advanced coordination to ensure continuity of care and safety during emergencies.

Children represent another dependent population requiring special consideration (Table 3-5). In Napa, over 28% of households include individuals under the age of 18, with over 7% of these households headed by a single caregiver. During emergencies, children are entirely dependent on caregivers for decision-making, transportation, and access to essential resources. Disruptions to schools, childcare, and youth services can result in significant emotional, educational, and developmental impacts. Families with limited means or single caregivers may also face greater challenges in securing housing, supplies, and recovery assistance.

Figure 3-5 highlights areas within Napa with higher concentrations of economically dependent age groups, informing targeted outreach and response strategies during emergencies.

Table 3-4: City of Napa Households with Seniors
Jurisdiction Households (HH) 65+ % 65+ Alone %
65+
Poverty %
Napa County 55,588 18,777 33.8% 4,816 8.7% 1,271 2.3%
City of American Canyon 5,924 1,772 29.9% 184 3.1% 111 1.9% City of Calistoga 2,330 1,003 43.0% 419 18.0% 101 4.3%
City of Napa 31,666 10,299 32.5% 2,674 8.4% 703 2.2%
City of St. Helena 2,963 1,153 38.9% 296 10.0% 42 1.4%
Town of Yountville 1,824 873 47.9% 351 19.2% 77 4.2%
Source: ACS 5-Year, 2017-2022
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Table 3-5: City of Napa Households with Children
Jurisdiction Households <18 %
<18 Single
Caregiver %
Napa County 55,588 14,596 26.3% 3,109 5.6%
City of American Canyon 5,924 2,633 44.4% 417 7.0%
City of Calistoga 2,330 471 20.2% 33 1.4%
City of Napa 31,666 8,934 28.2% 2,315 7.3%
City of St. Helena 2,963 619 20.9% 168 5.7%
Town of Yountville 1,824 160 8.8% 0 0.0%
Source: ACS 5-Year, 2017-2022
Elderly populations face increased risks during disaster events due to age-related health conditions, mobility limitations, and potential social isolation. In Napa, approximately 12% of the non-institutionalized population lives with a disability, this is on par with the countywide average (Table 3-6).

Among those with access and functional needs, elderly individuals with disabilities represent a highly vulnerable subpopulation when it comes to disaster preparedness, response, and recovery. This group includes seniors living with physical or cognitive impairments such as hearing or vision loss, reduced mobility, reliance on assistive medical devices, neurodivergence, or chronic health conditions that may be exacerbated by hazard events (e.g., exposure to wildfire smoke or extreme heat).

Figure 3-6 illustrates that in some portions of the city, more than 47% of the elderly population is estimated to have one or more disabilities, while other areas show lower proportions or lack available data. The spatial distribution shown on this map suggests that vulnerability is not uniform across the city and that certain neighborhoods may have greater needs for evacuation assistance, medical support, and continuity of care during emergencies. Seniors with disabilities may also be more sensitive to extended power outages, disruptions to medical services, and transportation interruptions. These risks are expected to increase under climate change conditions that intensify extreme heat events and strain emergency response resources.

The combination of advanced age and disability can present significant challenges not only during emergency response but also in implementing hazard mitigation measures. Elderly individuals with disabilities may face physical, financial, or logistical barriers to undertaking activities such as seismic retrofitting, anchoring fuel tanks, installing foundation bracing, or implementing residential flood-proofing techniques. Many live in older housing stock that is more vulnerable to earthquake damage or repetitive flooding and may lack the resources or support networks needed to complete mitigation upgrades.

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Table 3-6: City of Napa Population with Disabilities and Access to Transportation Jurisdiction Population
Persons
w/
Disability %
Persons
Reliant on
Public
Trans. % Households
HH w/o
Vehicle %
Napa County 137,384 16,544 12.0% 890 0.6% 55,588 2,421 4.4% City of American Canyon 21,669 2,201 10.2% 287 1.3% 5,924 138 2.3% City of Calistoga 5,191 573 11.0% 36 0.7% 2,330 83 3.6% City of Napa 79,233 9,837 12.4% 291 0.4% 31,666 1,554 4.9% City of St. Helena 5,426 683 12.6% 121 2.2% 2,963 219 7.4% Town of Yountville 3,397 683 20.1% 15 0.4% 1,824 210 11.5% Source: ACS 5-Year, 2017-2022
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Figure 3-5: City of Napa Dependent Age Groups Map
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Figure 3-6: City of Napa Disabled Elderly Map
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3.2.2.3 Race, Ethnicity & Language
Natural disasters compound racial disparities; non-white individuals and communities receive less recovery aid from FEMA than their white counterparts, even where the amount of damage is the same. (Howell, Junia; Elliott, James R., 2019) (National Advisory Council, 2020) These disparities are evidence of the complicated relationship between disaster recovery and overlapping social vulnerabilities including race, income, language, and health. Black and Latino residents are more likely to be low income and renters, conditions which create barriers to navigating FEMA’s Individual Assistance programs. Communities with more non-white residents may have lower tax revenue and property values, which means less investment in mitigation and rebuilding efforts before and after an emergency.

Figure 3-7 depicts the racial and ethnic composition within the City of Napa. According to ACS data, the population is predominantly White across much of the city, with notable concentrations of Hispanic or Latino residents in central and southern areas and Asian populations in the eastern portions of the planning area.

Residents with limited English proficiency (LEP) face heightened barriers to understanding emergency alerts, accessing preparedness resources, and navigating post-disaster recovery programs. In Napa, approximately 20% of households speak Spanish, but only around 3% report limited English proficiency. (Table 3-7). Figure 3-8 highlights where Spanish-speaking populations are concentrated in Napa.

Table 3-7: City of Napa Household Languages
Jurisdiction Households (HH) Spanish Speaking %
Limited
English %
Other
Lang. %
Napa County 55,588 8,738 15.7% 2,141 3.9% 12 0.0%
City of American Canyon 5,924 1,069 18.0% 177 3.0% - 0.0% City of Calistoga 2,330 474 20.3% 63 2.7% - 0.0%
City of Napa 31,666 5,800 18.3% 1,653 5.2% 9 0.0%
City of St. Helena 2,963 370 12.5% 88 3.0% - 0.0%
Town of Yountville 1,824 49 2.7% 21 1.2% - 0.0%
Source: ACS 5-Year, 2017-2022
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Figure 3-7: City of Napa Race and Ethnicity Map
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Figure 3-8: City of Napa Spanish-Speaking Households Map CAL OES SUBMITTAL - JUNE 2026
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3.2.2.4 Social Vulnerability Index (SVI)
The Centers for Disease Control and Prevention (CDC) Social Vulnerability Index (SVI) for City of Napa reveals important spatial and demographic patterns that have direct implications for equitable hazard mitigation planning. As discussed in detail in Volume 1, Section 1.5.3.6, the SVI is a composite measure developed by the CDC to identify communities that are more likely to require support before, during, and after a disaster. It incorporates a range of factors across four key dimensions: socioeconomic status, household composition and disability, minority status and language, and housing type and transportation access. The resulting index score ranges from 0 (lowest vulnerability) to 1 (highest vulnerability).

Figure 3-9 illustrates that social vulnerability in the City of Napa ranges from low to high (0.0 to 1.0), with most areas exhibiting moderate to moderately high SVI values. Higher SVI scores, indicating populations with reduced capacity to prepare for, respond to, and recover from hazard events, are primarily concentrated along the central north–south corridor of the city, generally following the Highway 29 and Napa River alignment. These areas reflect overlapping vulnerability factors such as lower income levels, higher proportions of renters, limited vehicle access, language barriers, and greater concentrations of elderly or disabled residents. In contrast, lower SVI values are more prevalent in outlying western, northeastern, and southeastern portions of the city, where populations may have greater access to resources and adaptive capacity.

The spatial pattern suggests that socially vulnerable populations are clustered in the urban core, increasing the potential for disproportionate impacts during hazard events such as flooding, extreme heat, earthquakes, and wildfire smoke episodes. Given the proximity of many higher-SVI areas to known floodprone zones along the Napa River, these populations may face compounded risks. Additionally, residents in these areas may encounter greater challenges in accessing emergency information, evacuation resources, sheltering options, and post-disaster recovery assistance, particularly during complex or prolonged hazard events.

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Figure 3-9: City of Napa CDC Social Vulnerability Index Map CAL OES SUBMITTAL - JUNE 2026
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Economy
The City of Napa serves as the primary economic center of Napa County, functioning as a regional hub for employment, commerce, government services, and tourism. The local economy is diverse, with key sectors including hospitality, wine production, retail, healthcare, and professional services. Napa’s location along major transportation corridors, including State Route 29 and State Route 121, reinforces its role as a central node for economic activity within the Napa Valley.

Commercial activity is concentrated in several key areas, including the downtown core, major commercial corridors such as Trancas Street and Soscol Avenue, and neighborhood-serving retail centers distributed throughout the city. These areas support a mix of visitor-serving businesses, restaurants, retail establishments, and essential services that contribute significantly to local tax revenues and employment opportunities. The concentration of economic activity within these corridors underscores the importance of protecting critical infrastructure, transportation networks, and utility systems from hazards such as flooding, earthquakes, wildfire smoke, and power outages.

Napa’s economy includes a strong base of small and locally owned businesses that support both residents and visitors. These businesses are particularly sensitive to hazard-related disruptions, as temporary closures, infrastructure damage, or reduced accessibility can lead to immediate revenue loss and longerterm economic impacts. Given the City’s reliance on tourism and hospitality, disruptions during peak visitor seasons can have amplified economic consequences. Ensuring business continuity and rapid recovery is therefore a key consideration in hazard mitigation planning.

A substantial portion of Napa’s workforce is employed in service-oriented and outdoor sectors, including hospitality, agriculture, construction, and maintenance. Workers in these industries may face increased exposure to hazards such as extreme heat, wildfire smoke, and poor air quality. Projected increases in the frequency and severity of heat events and wildfire conditions due to climate change have implications for worker health and safety, as well as overall economic productivity.

Economic vulnerability within the city is also influenced by income variability and employment stability, particularly among workers in hourly or service-based positions. Disaster-related closures, evacuations, or infrastructure disruptions can result in immediate income loss for these populations, potentially exacerbating household vulnerability and slowing community recovery. As such, protecting employment centers, maintaining reliable transportation access, and ensuring continuity of utilities, communications, and emergency services are essential strategies for reducing economic disruption and enhancing resilience in the City of Napa.

Growth Trends & Future Development
The City of Napa serves as the primary economic center of Napa County, functioning as a regional hub for employment, commerce, government services, and tourism. The local economy is diverse, with key sectors including hospitality, wine production, retail, healthcare, and professional services. Napa’s location along CAL OES SUBMITTAL - JUNE 2026
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major transportation corridors, including State Route 29 and State Route 121, reinforces its role as a central node for economic activity within the Napa Valley.

Commercial activity is concentrated in several key areas, including the downtown core, major commercial corridors such as Trancas Street and Soscol Avenue, and neighborhood-serving retail centers distributed throughout the city. These areas support a mix of visitor-serving businesses, restaurants, retail establishments, and essential services that contribute significantly to local tax revenues and employment opportunities. The concentration of economic activity within these corridors underscores the importance of protecting critical infrastructure, transportation networks, and utility systems from hazards such as flooding, earthquakes, wildfire smoke, and power outages.

Napa’s economy includes a strong base of small and locally owned businesses that support both residents and visitors. These businesses are particularly sensitive to hazard-related disruptions, as temporary closures, infrastructure damage, or reduced accessibility can lead to immediate revenue loss and longerterm economic impacts. Given the City’s reliance on tourism and hospitality, disruptions during peak visitor seasons can have amplified economic consequences. Ensuring business continuity and rapid recovery is therefore a key consideration in hazard mitigation planning.

A substantial portion of Napa’s workforce is employed in service-oriented and outdoor sectors, including hospitality, agriculture, construction, and maintenance. Workers in these industries may face increased exposure to hazards such as extreme heat, wildfire smoke, and poor air quality. Projected increases in the frequency and severity of heat events and wildfire conditions due to climate change have implications for worker health and safety, as well as overall economic productivity.

Economic vulnerability within the city is also influenced by income variability and employment stability, particularly among workers in hourly or service-based positions. Disaster-related closures, evacuations, or infrastructure disruptions can result in immediate income loss for these populations, potentially exacerbating household vulnerability and slowing community recovery. As such, protecting employment centers, maintaining reliable transportation access, and ensuring continuity of utilities, communications, and emergency services are essential strategies for reducing economic disruption and enhancing resilience in the City of Napa.

3.3 Planning Process
The City of Napa followed the planning process detailed in Volume 1, Section 2, including participating in the county-wide Hazard Mitigation Planning Team (HMPT) and formulating their own internal planning team to support the broader planning process.

The city’s representatives in the Steering Group led stakeholder and public engagement efforts alongside the Consultant Team, with assistance from the county-wide HMPT and their internal planning team. This engagement process is described in Volume 1. Specifically, for the City of Napa, this included postings to the city website and social media, and outreach events, as documented in Appendix B. Examples of Key CAL OES SUBMITTAL - JUNE 2026
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Stakeholders engaged by Napa County on behalf of the city with relevance to the development of Napa’s mitigation strategy include the USDA and other federal agencies; CAL FIRE and other state agencies; other neighboring jurisdictions; community-based organizations such as the Chamber of Commerce; utility providers like PG&E; UC Davis and other academia; and local businesses.

All Key Stakeholders that were invited to participate in the planning process are listed in Volume 1, Section 2, and the input received from stakeholders was integrated into the city’s annex, as described in Volume 1 Table 2-9. The city’s internal planning team participants, their positions, and how they participated in the planning process are shown in Table 3-8.

Table 3-8: City of Napa Planning Team and Steering Group Members Stakeholder Title Department CRS Expertise1
Description of
Involvement
Zach Curren Fire Chief Fire Dept.

Emergency
Services,
Preventive
measures (e.g.,
codes)
Jurisdictional Lead,
Attended Kick-Off
Meeting, HMPT
Meeting #2, & 3,
Jurisdictional
Breakout Meeting #2
Charles Rhodes Battalion Chief – (former
participant) Fire Dept.

Emergency
Services,
Preventive
measures (e.g.,
codes)
Attended Kick-Off
Meeting, HMPT
Meeting #1,
Jurisdictional Breakout
Meeting #1
Julie Lucido Public Works Director Public Works Dept.

Property
Protection,
Structural flood
control projects
Attended Jurisdictional
Breakout Meeting #1 &
#2
Doug DeMaster Senior Civil Engineer Public Works Dept., Water Division
Structural flood
control projects,
Property
Protection,
Attended Jurisdictional
Breakout Meeting #1 &
#2
Jaina French Community Relations &
Media Manager
City Manager’s
Office
Public Education
and Awareness
Attended Jurisdictional
Breakout Meeting #1 &
#2
Jeff Gittings Parks and Urban Forestry
Manager
Parks & Recreation
Services
Preventative
Measures, Natural
resource protection
Attended Jurisdictional
Breakout Meeting #2
Michael Walker Senior Planner Community
Development Dept.

Preventative
Measures
Attended Breakout
Meeting #2
Jason Williams Chief Building Official Building Dept.

Preventive
measures (e.g.,
codes)
Attended Breakout
Meeting #1 & #2
Matthew Price Public Works Maintenance
Superintendent Public Works Dept. Property protection (e.g., elevation) Attended Breakout
Meeting #2
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Stakeholder Title Department CRS Expertise1
Description of
Involvement
Michael Cahill Emergency Planning MPCahill Solutions
LLC
Emergency
Services
Attended HMPT
Meeting #3
Kristopher Jenny Lieutenant -
Administration Police Department Emergency Services
Attended Breakout
Meeting #2
Molly Rattigan
Deputy City
Manager/Interim
Community Development
Director
City Manager’s
Office & Community
Development
Preventive
measures (e.g.,
codes)
Attended Breakout
Meeting #2
Vincent Smith Community Development
Director-Former
Community
Development Dept.

Preventive
measures (e.g.,
codes)
Attended Breakout
Meeting #1
Jason Berens Deputy Chief Fire Dept. Emergency
Services
Attended Breakout
Meeting #1
Paul O'Neill Associate Planner Planning Division
Preventive
measures (e.g.,
codes)
No Participation to Date
Brandon Veyna Fire Prevention/Inspector Fire Dept.

Emergency
Services,
Preventive
measures (e.g.,
codes)
No Participation to Date
Ed Moore Engineering Assistant
Transportation
Engineering
No Participation to Date
Joy Eldredge Deputy Utilities Director Utilities Dept.

Property protection
(e.g., elevation) No Participation to Date
Stephanie
Emmons
Stormwater Program
Coordinator
Development
Engineering
Property protection
(e.g., elevation) No Participation to Date
Magdiel Frayre
Parks, Trees & Facilities
Supervisor
Parks, Trees &
Facilities Dept.

Natural Resource
Protection
No Participation to Date
Ed Moore Engineering Assistant
Transportation
Engineering
Natural Resource
Protection
No Participation to Date
1 The Community Rating System (CRS) categories of flood mitigation activities presented in this table are included for personnel cross-reference purposes only to support alignment with National Flood Insurance Program (NFIP) CRS crediting criteria. These categories are intended to assist in identifying departmental roles and expertise relevant to CRS activities and in maximizing CRS credit under Activity 510 (Floodplain Management Planning), including credit for multidepartmental involvement. Consistent with FEMA mitigation planning guidance (44 CFR § 201.6), mitigation actions included in this plan are those that reduce or eliminate long-term risk to people and property from natural hazards; therefore, activities associated solely with emergency response or short-term preparedness are not classified as mitigation actions.

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The City of Napa participated in a comprehensive hazard mitigation planning process as part of the 2026 Napa County MJHMP update. This included a series of breakout meetings that engaged the city’s planning team, which included key city personnel and stakeholders in evaluating hazards, identifying local vulnerabilities, and prioritizing mitigation strategies.

On September 25, 2024, the City of Napa held its first breakout session, which focused on the progress of the city’s hazard mitigation planning efforts. This meeting emphasized Napa’s role within the multijurisdictional framework and highlighted the need for sustained participation from major city departments and regional partners. Discussions included the increasing frequency and severity of natural disasters and the critical role of planning in reducing risk. The group reviewed newly released hazard data and addressed concerns about inaccuracies in updated CAL FIRE wildfire hazard maps, underscoring the importance of reliable data and state-level coordination to improve local risk modeling.

Building on this initial meeting, the City Planning Team reviewed historical hazard impacts, assess ongoing development trends, and evaluate the city’s capabilities and gaps in risk reduction. The breakout session included the development of a localized risk matrix to prioritize the hazards affecting the city, tailored to Napa’s unique geography and built environment, and laid the foundation for identifying hazard-specific problem statements and mitigation actions.

On June 12, 2025, the City of Napa convened Breakout Meeting #2 as part of the ongoing update to the Napa County Multi-Jurisdictional Hazard Mitigation Plan. This session built upon the foundational work of the initial breakout meeting by advancing the development of the mitigation strategy and refining priority actions. Discussions focused on evaluating and consolidating the City’s existing mitigation actions to ensure they are actionable, aligned with current funding opportunities, and consistent with FEMA guidance for implementable and maintainable plans (44 CFR § 201.6(c)(3)).

City staff and the Planning Team reviewed ongoing and proposed projects addressing key hazards such as flooding, wildfire, earthquake, erosion, and severe weather. Particular attention was given to aligning mitigation actions with available and anticipated funding sources, including state and local programs, in response to evolving federal funding conditions. The group emphasized the importance of developing specific, measurable, and feasible mitigation actions, consistent with FEMA’s Local Mitigation Planning Handbook (Task 6: Develop a Mitigation Strategy), and explored opportunities to integrate equity considerations and cross-agency coordination into project design.

The meeting also included refinement of the hazard profile by removing lower-priority hazards (e.g., pandemic and agricultural disaster) and clarifying the inclusion of others such as dam failure and severe weather, based on local conditions and recent events. Additionally, participants discussed strategies to enhance public engagement, including expanding outreach efforts and increasing participation in the community survey to support compliance with stakeholder involvement requirements under 44 CFR § 201.6(c)(1).

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Overall, Breakout Meeting #2 marked a transition from risk identification toward implementation-focused planning, ensuring that the City of Napa’s mitigation strategy remains data-driven, fiscally realistic, and aligned with both local priorities and state and federal mitigation frameworks.

These efforts built upon the county-wide meetings held between February 2024 and June 2025, which introduced the MJHMP update process, defined the roles of the Steering Group and city planning team, and outlined the timeline and deliverables for each participating jurisdiction. In addition to Napa's own session, previous workshops conducted on September 9, 2024, and June 12, 2025, introduced the hazard prioritization methodology, explored funding eligibility under the Federal Emergency Management Agency’s (FEMA) Hazard Mitigation Assistance (HMA) programs, and refined jurisdictional mitigation strategies.

Throughout this planning process, the City of Napa has remained focused on aligning its goals with FEMA standards, maintaining eligibility for federal mitigation funding, and incorporating updated risk data into planning and policy documents. These localized efforts are documented in this annex as well as in Volume 1 of the 2026 MJHMP. Table 3-9 shows meeting records for the City of Napa Planning Team. Steering Group and county-wide HMPT meetings are documented in Volume 1, Section 2.

Table 3-9: City of Napa Planning Team Meetings
Meeting & Date Agenda / Topics Goals / Key Inputs
County-Wide Steering Group and HMPT Kick-off and Meetings #1 & #2 February 28, 2024– July 18, 2024
City of Napa Planning
Team
Breakout Meeting #1
September 25, 2024
▪ County-wide HMPT meetings #1 thru #3 recap
▪ Community engagement progress and results
▪ Risk assessment and community vulnerability
▪ Demographics and vulnerable populations
▪ Overview of jurisdiction-specific hazard risks and
exposure
▪ Introduction to Risk Assessment Mapping Platform
(RAMP)
▪ Jurisdiction-specific hazard risk ranking exercise
▪ Project schedule updates and next steps
▪ Consensus on jurisdictionspecific priority hazards
▪ Identify capabilities and
potential mitigation actions
▪ Community engagement
volunteers
County-Wide HMPT Meeting #3
March 25, 2025
City of Napa Planning
Team
Breakout Meeting #2
June 12, 2025
▪ Breakout meeting #1 recap
▪ Community engagement progress and results
▪ Review areas of concern and define problem
statements
▪ Principles of effective mitigation strategies and
actions, and mitigation alternatives
▪ Refine and align jurisdiction-specific mitigation
actions exercise
▪ Project schedule updates and next steps
▪ Consensus on jurisdictionspecific areas of concern and problem statements
▪ Identify priority mitigation
actions
▪ Community engagement
volunteers
County-Wide HMPT Meeting #4
December 10, 2025
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Public Input & Draft Review
As detailed in Volume 1, Section 2, the draft plan was available for public review and comment from May 15 to June 2, 2026. Public comments received during that time were similar to those gathered throughout the public engagement process, including the need for more equity in the distribution of mitigation activities and funding and the need for enhanced cooperation among jurisdictions, utility providers, and state agencies. These comments were incorporated into the city’s mitigation strategy, as appropriate; although, most were already addressed by the Mitigation Action Plan which was based on previous public input.

Public and stakeholder input was gathered and incorporated throughout the plan development process, before the public review period, such as from the online public survey (see Volume 1, Section 2.1.2 and Appendix B, for details). During the review period, jurisdictional staff and stakeholders that participated in the plan development also reviewed the public draft and provided comments on minor corrections and revisions, which were addressed in the final plan.

3.4 What’s New
Since the City of Napa adopted its 2021 Local Hazard Mitigation Plan (LHMP), the City has actively pursued strategies to reduce natural hazard risks to life and property, demonstrating its commitment to resilience and preparedness. A comprehensive reevaluation of the mitigation actions outlined in the 2021 LHMP, has guided the city’s progress.

Mitigation Activities
The city has successfully implemented several initiatives aimed at addressing identified vulnerabilities.

Some of these accomplishments are highlighted in this section and have directly contributed to reducing risks from hazards such as flooding, all hazards, and severe weather. These completed projects showcase Napa’s ability to effectively plan, fund, and execute measures that protect its residents and infrastructure.

In addition, Napa has systematically reviewed and adjusted its mitigation actions, exemplifying adherence to FEMA’s Planning Policy Guide principles and emphasizing the importance of dynamic and adaptive mitigation planning. By fostering partnerships, leveraging funding opportunities, and prioritizing equity in implementation, the city aligns with best practices to build resilience against natural disasters. This ongoing effort is a testament to the city's commitment to the principles of risk-informed decision-making, equitable resource allocation, and integration with broader regional and state hazard mitigation objectives.

Adjustments to Previous Mitigation Actions
A significant portion of the city's mitigation efforts remain ongoing or in the pipeline. These actions, ranging from infrastructure upgrades to community outreach initiatives, represent the city’s proactive approach to addressing hazards as resources become available.

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Recognizing constraints such as limited funding, staffing, and shifting priorities, the city has reevaluated certain initiatives, leading to their reprioritization or canceling of mitigation actions. Factors such as feasibility, cost-effectiveness, and emerging risks informed these decisions, ensuring alignment with the city’s updated hazard mitigation goals. Adjustments to previous mitigation actions are documented as part of the City of Napa’s Mitigation Action Plan Table 3-18, and more specific status updates are provided in Table 3-19.

Successes Since 2021
Since the adoption of the 2021 Hazard Mitigation Plan, the City of Napa has made measurable progress in implementing mitigation actions that reduce risk and enhance community resilience. These successes reflect the City’s continued commitment to integrating hazard mitigation into local planning, capital improvement projects, and community programs.

The following success stories highlight completed and ongoing efforts that address key hazards such as wildfire, flooding, and infrastructure vulnerability. Collectively, these initiatives demonstrate Napa’s ability to move from planning to implementation by leveraging partnerships, securing funding, and advancing projects that provide long-term risk reduction benefits to the community.

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City of Napa Community Wildfire Protection Plan (CWPP)
The City of Napa’s Community Wildfire
Protection Plan (CWPP) is a strong
example of translating wildfire risk
into effective, community-driven
mitigation action. Through
collaboration with local fire agencies,
Napa County, and community
stakeholders, the City identified highrisk areas and prioritized strategies to reduce wildfire impacts in the
wildland-urban interface. This plan is
anticipated to be adopted in June 2026.

Key accomplishments include
expanded vegetation management and
defensible space programs, which
reduce fuel loads and improve
emergency access. The City has also
advanced home hardening efforts and
public outreach campaigns, helping
residents better protect their properties
from wildfire hazards.

In addition, the CWPP supports improvements to evacuation planning and coordination with regional partners and utility providers, strengthening overall emergency preparedness. The City has aligned these actions with available grant funding, ensuring that projects are both feasible and sustainable.

Overall, the CWPP demonstrates Napa’s commitment to proactive wildfire mitigation by combining planning, community engagement, and targeted investments to reduce risk and enhance resilience.

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Napa River / Napa Creek Flood Control
The Napa River & Creek Flood Protection Project represents a landmark achievement in reducing flood risk and enhancing resilience throughout the City of Napa. Developed through a collaborative partnership between the City, Napa County Flood Control and Water Conservation District, and federal and state agencies, the project reflects a long-term commitment to addressing one of the community’s most significant natural hazards.

A key success of the project is the implementation of a “living river” approach, which combines traditional flood control infrastructure with natural channel design. Improvements such as widened floodplains, restored wetlands, and stabilized riverbanks have increased the system’s capacity to manage high flows while also enhancing ecological function and public open space. These nature-based solutions reduce flood risk while providing co-benefits including habitat restoration, recreation, and improved water quality.

The project has significantly reduced the risk of flooding for thousands of properties, critical facilities, and infrastructure in Napa’s urban core. In addition, targeted improvements along tributary creeks have addressed localized flooding and erosion issues, further strengthening system-wide resilience.

Beyond physical improvements, the project demonstrates successful integration of mitigation into broader community planning. By leveraging multiple funding sources and maintaining strong interagency coordination, Napa has implemented a scalable and sustainable flood risk reduction strategy.

Overall, the Napa River & Creek Flood Protection Project stands as a model for innovative flood mitigation, showcasing how integrated, multi-benefit solutions can protect communities while enhancing environmental and social value.

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3.5 Risk Assessment
This section focuses on profiling hazards specific to the City of Napa and assessing their vulnerability independent of the broader county-wide planning area, which has been evaluated in Section 3 of Volume 1.

The hazard profiles in Volume 1 discuss overall impacts to the planning area and describe relevant plans, policies, and regulations; past events; location; frequency and probability of future occurrences; severity and extent; warning time; secondary hazards; and climate change impacts. For more information on risk assessment methodologies, see Volume 1, Appendix A.

This section includes a tailored vulnerability assessment, analyzing assets at risk such as population, property, and critical facilities and infrastructure unique to the city, and information on city-specific differences in hazard vulnerability across the planning area. It also identifies total city assets at risk, including people, property, and critical facilities and infrastructure within the city. In addition, this section presents growth and development trends for the community, offering insights into vulnerabilities and risks that represent the broader context of assets at risk.

Hazard Screening & Prioritization
Members of the Planning Team from each participating jurisdiction came together to collaboratively decide which county-wide hazards would be included in the MJHMP, and which would be excluded. Hazard screening and prioritization took place early in the process and integrated historic data, local knowledge, and consensus opinions to create a risk assessment matrix for the county as well as for each participating jurisdiction. These matrices indicate the priority of hazards prior to further refinement. Details about this process, the results of the discussion, and in-depth profiles for county-wide hazards can be found in Volume 1, Sections 2 and 3.

The final results of the hazard screening and prioritization exercises are summarized in Table 3-11, including which specific subhazards were selected by Napa’s Planning Team.

The City of Napa’s internal planning group used the same hazard identification and prioritization process as the county-wide Planning Team. They reviewed previously prepared hazard mitigation plans and other relevant documents to determine the realm of natural hazards that have the potential to affect the city.

Table 3-10 provides a crosswalk of hazards identified in select planning documents, including the 2020 Napa County MJHMP, the City of Napa’s General Plan, and the 2023 State of California HMP. The crosswalk was used to develop a preliminary hazards list, providing a framework for the group to evaluate which hazards were truly relevant to the City of Napa and which ones were not.

The internal planning group then ranked hazards based on their probability of affecting City of Napa and potential impacts on the community. Figure 3-10 displays the results of the hazard risk ranking exercise that was performed before further refinement. All hazards have been profiled in Volume 1 of this document.

The purpose of this annex is to specifically address the city’s vulnerability to specifically identified hazards.

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Table 3-10: City of Napa Document Review of Potential Hazards Hazard
2020 Napa County
MJHMP City of Napa General Plan
2023 California
SHMP
Agricultural Pests ■ ■
Avalanche ■
Climate Change ■ ■ ■
Coastal ■
Dam Failure ■ ■
Drought ■ ■ ■
Earthquake / Liquefaction ■ ■ ■
Extreme Cold ■
Extreme Heat ■ ■
Extreme Weather / Storms ■ ■ ■
Flood ■ ■ ■
Geologic / Mass Movement ■ ■ ■
Human-Caused ■ ■
Insects ■
Levee Failure ■
Pandemic Disease ■ ■
Sea Level Rise ■
Soil ■
Subsidence ■
Tornado ■
Tsunami / Seiche Wave ■
Volcano ■
Wildfire ■ ■ ■
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Figure 3-10: City of Napa Risk Assessment Matrix
Note: Hazard naming in the Risk Assessment Matrix may not match the final naming used. Refer to hazards prioritization summary table.

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Priority Hazards
The results of the initial risk ranking exercise completed by the city’s Planning Team, before further refinement, are identified in the county’s completed matrix in Figure 3-10. Table 3-11 provides the final list of priority hazards and subhazards with additional details about why certain hazards were chosen and why others were not prioritized. However, it should be noted that many hazards not prioritized for profiling are briefly discussed as secondary or compounding hazards, and subhazards that were profiled and included in the risk assessment are listed specifically.

Table 3-11: City of Napa Hazards Prioritization Summary Hazard Priority Explanation
Earthquake / Liquefaction High Profiled in Volume 1, Section 3.3.4, and Section 0 in this annex, including Liquefaction
Wildfire High Profiled in Volume 1, Section 3.3.1, and Section 3.5.2.1 in this annex Flood High Profiled in Volume 1, Section 3.3.2, and Section 3.5.2.3 in this annex, including Levee Failure
Levee Failure High Profiled in Volume 1, Section 3.3.2, and Section 3.5.2.3 in this annex under Flood
Extreme Weather / Storms High
Profiled in Volume 1, Section 3.3.5, and Section 3.5.2.6 in this annex as Severe Weather, including High Wind and Heavy Rain (Winter Weather not a priority due to low probability and impact potential) Drought High Profiled in Volume 1, Section 3.3.6, and Section 3.5.2.5 in this annex Geologic / Mass Movement -
Profiled in Volume 1, Section 3.3.5; not a priority due to low probability and impact potential
Extreme Heat High Profiled in Volume 1, Section 3.3.8, and Section 3.5.2.7 in this annex Agricultural Pests -
Profiled in Volume 1, Section 3.3.9; not a priority due to low probability and impact potential and jurisdictional focus
Sea Level Rise High Profiled in Volume 1, Section 3.3.9, and Section 3.5.2.8 in this annex under Climate Change
Climate Change High
Profiled in Volume 1, Section 3.3.9, and Section 3.5.2.8 in this annex, including Sea Level Rise, and discussed as a compounding hazard in relevant profiles
Dam Failure High Profiled in Volume 1, Section 3.3.3, and Section 3.5.2.2 in this annex CAL OES SUBMITTAL - JUNE 2026
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Vulnerability to Specific Hazards
Assessing vulnerabilities exposes the unique characteristics of individual hazards and begins the process of narrowing down which areas within the city are vulnerable to specific hazard events. The vulnerability assessment considered unique local knowledge of hazards and impacts and a GIS overlaying method for examining such vulnerabilities in more depth. Using these methods, the city’s planning group estimated vulnerable populations, properties, and assets, and potential losses. In addition, the exposure of city assets to drought, geological, earthquake, wildfire and flood hazards were also considered.

Many of the hazard profiles include a snapshot map and damage estimation tables that illustrate the city’s vulnerabilities to those specific hazards. These maps assisted the planning group in understanding the hazard exposure of populations, parcels, and critical facilities and infrastructure. Each snapshot map contains an exposure summary that displays the percentage of the population, the improvement and content value of parcels, and the amount of critical infrastructure that is exposed. For hazards without geospatial extents, such as drought and severe weather, narratives are provided instead of exposure maps and tables.

Based on the hazard prioritization exercise, this vulnerability assessment focuses on eight hazards for the City of Napa, some of which encompass sub hazards such as Liquefaction and Heavy Rain Wildfire
SECTION 3.5.2.1
Flood
SECTION 3.5.2.2
Dam Failure
SECTION 3.5.2.2
Earthquake
SECTION 0
Drought
SECTION 3.5.2.5
Severe Weather
SECTION 3.5.2.6
Extreme Heat
SECTION 3.5.2.7
Climate Change
SECTION 3.5.2.8
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3.5.2.1 Wildfire Hazard
Wildfire risk within the City of Napa is primarily concentrated along the peripheral edges of the city, where urban development transitions into surrounding open space, foothills, and vegetated lands characteristic of Napa County. As illustrated in the wildfire risk exposure map (Figure 3-11), the highest concentrations of wildfire hazard are located east and west of the city limits, with Moderate and High hazard zones extending into portions of the City’s Sphere of Influence and at the wildland–urban interface (WUI).

The eastern boundary of the City, extending toward the Silverado Trail corridor and adjacent foothill areas, exhibits Moderate to High wildfire hazard. These areas are characterized by grasslands, chaparral, and mixed vegetation that can become highly combustible during Napa’s dry summer and fall seasons. Winddriven fire behavior and topographic influences in these foothill environments increase the likelihood of rapid fire spread. Development patterns near these edges—including low-density residential neighborhoods and transportation corridors—may face elevated risk from ember intrusion, limited evacuation routes, and constrained emergency access, consistent with wildfire risk characteristics identified in the City’s Hazard Mitigation Plan.

Similarly, the western and southwestern edges of the City, including areas near the Napa River corridor and transitioning toward Carneros and adjacent open space, show Moderate wildfire hazard exposure. While portions of these areas include wetlands and irrigated agricultural lands that can act as partial fire breaks, seasonal drying of grasses and vegetation—particularly during drought conditions—can contribute to localized wildfire risk. Wind patterns and alignment with open space corridors may further influence fire behavior in these areas.

Within the centralized and more urbanized portions of the City of Napa, wildfire risk is generally lower, with the map indicating minimal exposure to High or Very High hazard categories. Consistent with the exposure summary shown in the map, there are no mapped population, parcel, or critical infrastructure exposures within the Very High wildfire hazard category inside city limits, resulting in exposure rates of approximately zero percent for these asset classes. However, the map identifies localized areas of High hazard exposure, including transportation-related assets, with approximately 25 transportation-related features (7%) located within hazard areas, indicating some vulnerability of critical lifeline infrastructure.

Despite the relatively limited extent of Very High wildfire hazard zones within incorporated city boundaries, wildfire remains a significant planning concern for the City of Napa. The City is directly adjacent to higher hazard areas throughout Napa County, and regional wildfire events—such as those documented in the Napa County Community Wildfire Protection Plan—demonstrate the potential for fires originating outside city limits to impact urban areas through ember cast, smoke, and evacuation demands.

The City recognizes that wildfire risk is influenced not only by mapped hazard zones but also by proximity, connectivity of fuels, and interjurisdictional fire behavior. Climate change is expected to exacerbate these conditions through increasing temperatures, prolonged drought, and more frequent extreme weather events, contributing to longer fire seasons and more severe wildfire behavior across Napa County.

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Figure 3-11: Exposure Summary- City of Napa Wildfire Risk CAL OES SUBMITTAL - JUNE 2026
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3.5.2.2 Dam Failure Hazard
Dam failure represents a low-frequency but potentially high-consequence hazard within the City of Napa.

Dam failure refers to the partial or complete structural failure of an upstream dam, resulting in the uncontrolled release of stored water and rapid downstream inundation. As shown in Figure 3-12, portions of the city are located within mapped dam inundation zones, primarily along the Napa River corridor and extending into low-lying areas in the southern portion of the city.

Exposure within the mapped inundation area is moderate relative to other hazards but remains significant in terms of potential consequences. Approximately 13,000 residents, representing roughly 15 to 20 percent of the City’s population, are located within potential inundation areas. Similarly, on the order of 6,000 parcels fall within the inundation zone, representing a comparable share of total development. The total value of exposed structures and contents is substantial, estimated in the range of several billion dollars, indicating the potential for considerable economic losses in the event of a failure scenario. Critical infrastructure exposure is present but variable, with certain categories, such as hazardous materials sites and transportation and lifeline systems, showing higher relative exposure compared to essential facilities.

Dam failure hazards are typically associated with structural failure, overtopping, seismic activity, internal erosion, extreme precipitation events, or operational malfunctions affecting reservoir systems. In the Napa Valley watershed, failure scenarios could generate rapid downstream flooding along the Napa River and its tributaries, resulting in high-velocity flow conditions, debris transport, and localized erosion. The relatively confined river corridor in some areas, combined with urban development along the floodplain, may increase flow depths and reduce available warning time.

Potential impacts within the City of Napa are primarily associated with sudden inundation and its cascading effects. Floodwaters could damage residential, commercial, and industrial structures, as well as critical infrastructure including roadways, bridges, and utilities. Inundation may also disrupt key transportation routes, particularly those crossing or running parallel to the Napa River, limiting access for emergency response and recovery operations. Additionally, floodwaters may transport sediment, debris, and contaminants, affecting water quality and potentially disrupting stormwater and wastewater systems.

Seismic activity represents an important consideration in dam failure risk. Earthquakes similar to those described in the scenario analysis may impose structural stress on upstream dams, potentially contributing to failure under extreme conditions. In addition, intense storm events and prolonged rainfall may increase reservoir levels and inflow volumes, raising the likelihood of overtopping or operational strain on dam infrastructure.

Although the spatial extent of dam inundation is smaller than that of riverine flooding, the hazard is characterized by rapid onset, limited warning time, and high consequence, which increases life safety risks for exposed populations. The concentration of development and infrastructure within portions of the inundation zone further underscores the importance of coordinated emergency planning and public awareness.

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Figure 3-12: Exposure Summary – City of Napa Dam Inundation Zone CAL OES SUBMITTAL - JUNE 2026
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3.5.2.3 Flood Hazard
Flooding is a significant natural hazard for the City of Napa due to its location within the Napa River watershed, relatively flat valley topography, and proximity to tidally influenced downstream systems.

Portions of the City are subject to riverine flooding, localized stormwater flooding, and backwater effects, particularly during major precipitation events when high flows in the Napa River coincide with limited drainage capacity and downstream tidal influences. Flood hazard areas within the city are primarily concentrated along the Napa River corridor and its tributaries, including Napa Creek and Browns Valley Creek, as well as in localized low-lying areas throughout the community.

The FEMA Flood Risk Exposure map (Figure 3-14), shows areas within the 100-year (1% annual chance) and 500-year (0.2% annual chance) floodplains, including mapped floodway areas and levee-protected areas. As illustrated in Figure 3-14, flood-prone areas extend north to south through the central portion of the City following the Napa River corridor, with additional tributary and drainage-related flood hazard areas extending into developed neighborhoods. These flood-prone areas reflect the combined influence of river overflow, stormwater runoff, and constrained urban drainage systems. Flood hazards may be exacerbated during extreme storm events when elevated river flows coincide with downstream tidal conditions.

Exposure analysis indicates that over 12,000 residents, representing a notable portion of the City’s population, are located within mapped flood hazard areas. In addition, several thousand parcels, accounting for a meaningful share of the City’s total development, are exposed to flooding. The estimated building and contents value within flood hazard areas exceeds $1 billion, reflecting a substantial concentration of economic assets within flood-prone areas of the community.

Critical infrastructure exposure is also significant. Essential facilities, hazardous materials sites, and high potential loss facilities are located within mapped flood hazard areas, indicating potential risks to public safety and environmental resources during flood events. In addition, transportation and lifeline infrastructure is widely intersected by flood-prone areas, highlighting the potential for roadway closures, access limitations, and disruption of essential services during flood events (Figure 3-14).

Flooding in the City of Napa can result in structural damage to buildings, roadway inundation, utility system impacts, and economic disruption. Flooding along the Napa River corridor has historically affected both residential and commercial areas, and localized flooding can impact neighborhoods with limited stormwater capacity. Secondary impacts include erosion, sediment deposition, and strain on flood control infrastructure, particularly during repetitive or prolonged storm events.

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Figure 3-13: City of Napa Flood Risk (FEMA and DWR Awareness Zones) CAL OES SUBMITTAL - JUNE 2026
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Figure 3-14: Exposure Summary – City of Napa Flood Risk (FEMA Zones) CAL OES SUBMITTAL - JUNE 2026
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National Flood Insurance Program
The National Flood Insurance Program (NFIP) makes federally backed flood insurance available to homeowners, renters, and business owners in participating communities. FEMA has prepared a detailed Flood Insurance Study (FIS) for Napa County and municipalities. The study presents water surface elevations for floods of various magnitudes, including the 1% annual chance flood (100-YR flood) and the

0.2% annual chance flood (500-YR flood). Base flood elevations and the boundaries of the 100- and 500-YR floodplains are shown on Flood Insurance Rate Maps (FIRMs), which are the principal tools for identifying the extent and location of the flood hazard. FIRMs are the most detailed and consistent data source available, and for many communities they represent the minimum area of oversight under their floodplain management program. See Section 4 of Volume 1 for general information on the NFIP.

The City of Napa has participated in the NFIP since 1979 and has adopted the most recent FIRMs and FIS issued by FEMA (dated August 3, 2016) as well as local floodplain development regulations in compliance with the minimum NFIP standards established in the City of Napa Municipal Code (§ 17.38.060 Floodplain Management Regulations). These minimum standards include procedures and provisions for substantial improvements and substantial damages to existing structures, the latter of which are employed by the floodplain administrator and city building inspectors following any hazard event affecting structures located in the flood hazard area in accordance with NFIP requirements. Regulations for substantial improvements are enforced via permitting procedures. Implementation and enforcement of the city’s floodplain regulations are assigned to the Public Works Director, who serves as the floodplain administrator.

The City of Napa is currently in good standing with the provisions of the NFIP. Compliance is monitored by FEMA regional staff and by the California Department of Water Resources under a contract with FEMA.

Maintaining compliance under the NFIP is an important component of flood risk reduction. See Figure 3-12 for more information on the City’s policies and historic flood insurance claims.

Table 3-12: City of Napa National Flood Insurance Program Information City of Napa NFIP and CRS Status and Flood Insurance Statistics NFIP Status Participating since 9/05/79
Community Identification (CID) 060207
CRS Class (Entry Date) Class 7 (4/01/2001)
Policies in Force (Total Coverage) 567 Policies / ($160,708,000 Coverage) Policies Inside SFHA / Outside SFHA 420 Inside / 147 Outside Total Claims (Total Paid) 890 Claims ($20,595,186 Paid) Repetitive Loss (RL) / Severe Repetitive Loss (SRL) Properties 50 RL / 12 SRL Repetitive Loss Payments (Building / Contents) $4,822,687 / $1,699,117 Note: The number of policies is by property and does not count policies for individual buildings. The Privacy Act of 1974 (5 USC 522a) restricts the release of certain types of data to the public. Flood insurance policy and claims data is included in the list of restricted information. FEMA can only release such data to state and local governments, and only if the data is used for floodplain management, mitigation, or research purposes. Therefore, this plan does not identify the repetitive loss properties or include claims data for any individual property.

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Principal Flooding Sources
Flood hazard conditions can exist along the entire length of the Napa River as it flows through the City as well as along the course of several tributary creeks. Flooding in the City has occurred when the Napa River’s flow at Oak Knoll Avenue, which is just north of the City limits, has exceeded about 15,000 cubic feet per second. Some areas (typically agricultural land) will remain flooded for several weeks due to inadequate drainage, however, it is more typically true that such areas are only inundated for between one and three days. (City of Napa Hazard Mitigation Plan, 2015)
Napa Creek floodwaters have had a particularly significant impact on the center of the city. For instance, during the 1986 flood, Napa Creek overflowed on the south side of its banks. It flooded areas along Coombs Street and the parkway Plaza Mall as well as the downtown area. This was similar to a flooding event which occurred in 1942. The completion of the Napa Creek Flood Protection Project is a significant mitigation to the threat of flooding and has been predicted to significantly reduce or eliminate property damage from 100- year storm events, especially in the downtown Napa River Oxbow area. (Id.) Localized flooding may sometimes occur outside of recognized drainage channels or delineated floodplains due to a combination of locally heavy precipitation, increased surface runoff, and inadequate facilities for drainage and stormwater conveyance. Such events most typically occur in flat areas and in urbanized areas with extensive impermeable surfaces. Local drainage may result in “nuisance flooding,” in which streets or parking lots are temporarily closed and minor property damage occurs.

Napa River-Napa Creek Flood Protection Project
After a long history of destructive flooding in Napa, the city undertook a comprehensive project to reduce flooding, known as the Napa River-Napa Creek Flood Protection Project. Parts of the project have been completed while other parts are ongoing. The location of flooding in the city has already been significantly reduced thanks to completed phases of the Project.

The first major hurdle the City faced was funding such a large-scale effort. Two-thirds of voters in Napa County passed Measure A in March of 1998. This half-cent local sales tax levy provides a funding mechanism for the local share of the project cost and helped solidify the partnership between the Napa County Flood Control and Water Conservation District (NCFCWCD) and the U.S. Army Corps of Engineers.

Measure A funds flood protection, drainage improvements, dam safety, and watershed management projects for each community in Napa County and in the unincorporated area of the county. (FEMA, 2021) In 2000, the Napa County Flood Control and Water Conservation District in conjunction with the Army Corps of Engineers embarked on what would be a 16-year project to improve flood measures along the Napa River.

Phase one of the Napa Creek Bypass Project was completed in 2012 and resulted in a large number of properties being mapped out of the floodway and floodplain.

The second phase of the Flood Project "Napa River Dry Bypass" was completed in the fall of 2016 and was successfully put to the test several times during the 2016-2017 rainy season when the County received CAL OES SUBMITTAL - JUNE 2026
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record amounts of rainfall. The City and Flood District have worked diligently with FEMA to produce a revised flood map that reflects the latest flood control improvements. The revised flood maps have been approved under the Napa Post-Bypass Letter of Map Revision (LOMR 16-09-1316P) with an effective date of January 22, 2019.

The Oxbow Bypass is a key part of the project. The bypass is a wet/dry channel that allows for the inundation of high flows from the Napa River during winter months to reduce high flows that would often back up and flood downtown Napa. The bypass includes flood gates to further protect downtown Napa from flooding.

The bypass also serves as a community park, Oxbow Commons, which opened in 2015. The bypass is just one of many successes of the Project throughout the city that have reduced flood impacts.

Repetitive Loss Area Analysis
A repetitive loss (RL) property is a FEMA designation, defined as an insured property (or formerly insured) that has made two or more claims of more than $1,000 in any rolling 10-year period since 1978. Claims must be at least 10 days apart but within 10 years of each other. The term “rolling 10-year period” means that a claim of $1,000 can be made in 1991 and another claim for $2,500 in 2000, or one claim in 2001 and another in 2007, as long as both qualifying claims happen within 10 years of each other. A RL property may be classified as a Severe Repetitive Loss (SRL) property under certain conditions: the property has had four or more claims of at least $5,000, or at least two claims that cumulatively exceed the buildings reported value.

Extensive FEMA NFIP databases are used to track claims for every participating community, including the City of Napa. Currently, the city contains 55 unmitigated RL properties city-wide. The total dollar amount of claims paid to date by the NFIP for these RL properties are made available in Figure 3-15.

A property does not have to be currently carrying a flood insurance policy to be considered a RL or SRL property. Often homes in communities do not carry flood insurance but are still on the community’s repetitive loss list. The “repetitive loss” designation follows a property from owner to owner, from insurance policy to no insurance policy, and even after the property has been mitigated. Having an insurance policy and making claims that fall into the repetitive loss criteria will put a property on the RL list. Even after the policy on a property has lapsed or been terminated, the property will remain on the City’s RL list.

This Repetitive Loss Areas Analysis (RLAA) examines areas where multiple RL properties exist in close proximity to each other and share similar flooding source conditions. Six RL areas have been identified as part of the city’s RLAA. Most RLAA areas are a result of flood damage caused by the Napa River. Local tributaries such as Napa Creek and Kreuse Creek also contribute to flood losses during high water events in RLAA areas. Figure 3-15 shows the repetitive loss areas in the City of Napa along with the information on claim data, historic loss information and current property value information in total. Figure 3-16 through Figure 3-21 show individualized claim and property data for each repetitive loss area.

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Figure 3-15: City of Napa Repetitive Loss Areas
The Privacy Act of 1974 (5
U.S.C. 522a) restricts the
release of certain types of
data to the public, including
Flood insurance policy and
claims data. FEMA can only
release such data to state
and local governments, and
only if the data is used for
floodplain management,
mitigation, or research
purposes. Therefore, this
plan does not identify the
repetitive loss properties or
include claims data for any
individual property.

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Stonecrest RL Area
The Stonecrest RL Area is located near Stonecrest Avenue and Highway 121. This repetitive loss area consists of two properties on along the banks of the Napa River. Figure 3-16 indicates the area of generalized repetitive loss claims, payout information, and the FEMA identified flood hazard at Stonecrest. Most properties on the Napa River have significant risk to flooding, as indicated by past flood occurrences and past claims. One property is a SLR property with more than seven different claims dating back to 1985. Most properties or homes are not within the FEMA 100-YR Floodplain; however, there is a low-lying section of land along the banks of the Napa River that may contribute to flood damage in this area. The SFHA “Effective” FIRM indicates Base Flood Elevations (BFEs) of approximately 27.2 to 26.6 feet for the Napa River Floodway and the low-lying area is approximately 22 to 25 feet.

RiverPointe RL Area
RiverPointe RL Area is located along the west bank of the Napa River at Lincoln Avenue. This area is named after the RiverPointe Napa Valley Resort. It’s known by local flood control and emergency management personnel that the Napa River jumps the west bank at this location due to the capacity of the Lincoln Avenue Bridge. Flood waters travel from the Napa River west down Lincoln Avenue and inundate areas north of Lincoln Avenue first; waters then flow across Lincoln Avenue at low-lying areas to the south. This repetitive loss area consists of 28 properties, located both north and south of Lincoln Avenue. Figure 3-17 indicates the area of generalized repetitive loss claims and payout information for RiverPointe. Most properties within this area have significant risk to flooding, as indicated by past flood occurrences and past claims, especially at the intersection of Lincoln Avenue and Soscol Avenue. Six properties in the RiverPointe Area are SLR properties. All RL properties within the RiverPointe Area are within the FEMA 100-YR Floodplain, and almost half are within the floodway of the Napa River. It is important to note that over four million dollars of claims have been paid by the NFIP in this area. Average payouts are more than $50,000 for each occurrence due to the commercial nature of many properties.

Soscol North RL Area
Soscol North RL Area is just south of the RiverPointe RL Area on Soscol Avenue. This RL area consists of five properties between Yount Street and Caymus Street along Yajome Street. Most properties within this area have significant risk of flooding, as indicated by past flood occurrences, past claims, and the proximity to the floodway. Figure 3-18 indicates the area of generalized repetitive loss claims, payout information, and the FEMA-identified flood hazard. All properties within this RL Area are within the FEMA 100-YR Floodplain.

The SFHA “Effective” FIRM indicates BFEs of approximately 21 feet within this area, with most of the damage caused by the split flow of the Napa River during high water events and the low-lying nature of this area in the floodway.

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Oxbow West RL Area
The Oxbow West RL Area is located on the west bank for the Napa River oxbow. This RL area consists of three RL properties within the oxbow, to the east of the “dry river bypass.” Most properties within the oxbow have significant risk to flooding, as indicated by past flood occurrences and past claims. Figure 3-19 indicates the area of generalized repetitive loss claims, payout information, and the FEMA-identified flood hazard for this area. Flood risk has been reduced in recent years with the construction of the Napa River dry bypass and construction of flood gates to protect the oxbow from high water events; however, these RL properties are unmitigated according to FEMA. The SFHA “Effective” FIRM indicates BFEs of approximately

19.5 feet for the dry bypass floodway and approximately 19.7 feet for areas in the 100-YR floodplain near Vernon Street. Average payouts are more than $40,000 for each occurrence due to the commercial nature of the properties.

Oxbox East RL Area
The Oxbow East RL Area is located on the east bank for the Napa River oxbow. This RL area consists of 13 RL properties on the east bank of the Napa River. Most properties on within the oxbow have significant risk to flooding, as indicated by past flood occurrences and past claims. Figure 3-20 indicates the area of generalized repetitive loss claims, payout information and the FEMA-identified flood hazard for this area.

Flood risk has been reduced in recent years with the construction of the Napa River dry bypass to alleviate this neighborhood from high water events; however, these RL properties are unmitigated according to FEMA. All properties in this RL Area are within the FEMA 100-YR Floodplain and the Napa River oxbow overflow area. The SFHA “Effective” FIRM indicates BFEs of 19.7 feet for areas near 2nd and Post Streets down to 18.3 feet for areas near 3rd Street. It is important to note that over one million dollars of claims have been paid by the NFIP in this area.

Soscol South RL Area
The Soscol RL Area is located on Soscol Ave between 8th Street and Sousa Lane. This RL area consists of 3 RL properties within the southern area of the Napa River oxbow overflow. Most properties in this overflow area have significant risk of flooding, as indicated by past flood occurrences and past claims. Figure 3-17 indicates the area of generalized repetitive loss claims, payout information, and the FEMA-identified flood hazard for this area. Flood risk has been reduced in recent years with the construction of the Napa River dry bypass to alleviate this neighborhood from high water events; however, these RL properties are unmitigated according to FEMA. All properties in this RL Area are within the FEMA 100-YR Floodplain. The SFHA “Effective” FIRM indicates BFEs of 16.2 feet for areas near 8th Street and dropping to approximately 15.7 feet for areas near Sousa Lane. It is important to note that Kreuse Creek may contribute to flood risk in this area.

It’s been reported that Kreuse Creek backs up at Soscol Avenue and runs north down Soscol Avenue which may contribute to losses within this area. Average payouts are more than $45,000 for each occurrence due to the commercial nature of the properties.

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Figure 3-16: Stonecrest RL Area
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Figure 3-17: RiverPointe RL Area
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Figure 3-18: Soscol North RL Area
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Figure 3-19: Oxbow West RL Area
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Figure 3-20: Oxbow East RL Area
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Figure 3-21: Soscol South RL Area
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Frequency & Probability of Future Occurrences
The City of Napa will most likely experience flooding in the future, with the probability of flooding in the City of Napa between 10 and 100% annually. Winter storms saturate soils in Napa County during the months of November through April. Napa County experiences “atmospheric river storms” that can deliver over an inch of rain per hour for extended time frames, producing flooding in local tributary streams and the Napa River. The 100-year flood is calculated to be the level of flood water expected to be equaled or exceeded every 100 years on. The term is used to describe an event that has a 1-in-100 chance of happening in any given year. In reality, there is a 65% chance that there will be a 100-year flood in 100 years. Likewise, a 50-year flood has a 2% chance of happening in any given year, and there’s a 4% chance of a 25-year flood every year.

Calculations are based on less than a hundred years of flood records. The Napa River Flood Project has been constructed to protect the community from this 100-year event, which would be a larger flood than the 1986, 1995, or 2005 flood events.

Less Frequent Flooding Areas
In addition to mapped flood hazard areas, the City of Napa is subject to less frequent, higher magnitude flood events that extend beyond the limits of the currently mapped floodplain. These events include the 0.2% annual chance flood (500-year event) and other extreme storm scenarios that may exceed the capacity of existing flood control and drainage systems.

Analysis of Best Available Mapping (BAM) data from the California Department of Water Resources (DWR) indicates that additional areas—particularly along tributary systems and upstream watershed corridors— have the potential to experience inundation beyond the FEMA-mapped Special Flood Hazard Areas (SFHAs).

These areas are shown in red on the accompanying map and represent locations where flooding may occur under larger storm events or changing watershed conditions. Less frequent flooding is most likely to occur in:
▪ Upper Napa River corridor north of downtown where floodwaters expand beyond the primary channel;
▪ Downtown Napa and Oxbow District, where backwater effects and system capacity constraints may occur;
▪ Southern Napa near the Napa River estuary and airport, where tidal influence and storm surge interactions increase flood extent;
▪ Tributary corridors, including Napa Creek, Tulucay Creek, Salvador Creek, and other smaller drainages where localized flooding may exceed mapped extents.

The DWR BAM analysis highlights tributary reaches and upland drainage pathways that are not fully captured in FEMA mapping but may convey significant flood flows during extreme events (Figure 3-13).

Flood severity in the City of Napa is primarily influenced by flow depth and velocity, both of which increase during less frequent flood events. High-velocity flows, particularly in confined channels or where floodwaters overtop banks, can result in:

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▪ Structural damage from debris impact;
▪ Channel migration and erosion;
▪ Infrastructure failure (roads, bridges, culverts);
▪ Rapid inundation of developed areas.

The main factors affecting flood damage are water depth and velocity. Deeper and faster flood flows can cause more damage. Shallow flooding with high velocities can cause as much damage as deep flooding with slow velocity. Peak discharge data further illustrates the magnitude of these events. For example:
▪ Napa River; upstream of Imola Avenue is estimated to convey, ~44,390 cubic feet per second (cfs) during a 1% annual chance event; ~53,450 cfs during a 0.2% annual chance event. ▪ Upstream of Bull Island; flows may reach convey ~45,200 cfs (1% event) and up to ~69,000 cfs (0.2% event)
▪ Tributaries such as Tulucay Creek; may experience flows exceeding ~4,530 cfs (1% event) and ~5,500 cfs (0.2% event)
These increases in discharge significantly expand flood extents and intensify hydraulic conditions, particularly where floodwaters leave the main channel and spread across developed floodplains. This is especially true when a channel migrates over a broad floodplain, redirecting high velocity flows and transporting debris and sediment. Flood severity is often evaluated by examining peak discharges; Table 3-13 lists peak flows used by FEMA to map City of Napa floodplains.

Table 3-13: Summary of Relevant Discharges in Napa County Drainage
sq. Miles
Peak Discharge (cubic feet/second)
Flooding Source/Location 10-
percent
2-
percent
1-percent 0.2-
percent
Blossom Creek
At confluence with Napa River 3.4 1,000 N/A 1,700 2,000 Cyrus Creek
At confluence with Napa River 2.9 900 N/A 1,500 1,900
Garnett Creek
At confluence with Napa River 6.9 1,900 N/A 3,200 3,900 Napa Creek
At mouth 14.9 * * 4,300 *
At the City of Napa corporate limits 14.9 2,200 * 3,500 4,500 Napa River
Upstream of Bull Island 324 25,500 38,900 45,200 69,000 Upstream of Imola Avenue 300 26,770 39,200 44,390 53,450 Upstream of confluence of Tulucay Creek * 25,810 38,010 42,720 51,260 Upstream of confluence of Napa Creek * 20,040 35,600 40,100 48,300 Upstream of Trancas Street * 22,750 33,430 39,000 44,540 Near the City of Napa (Oak Knoll Avenue) 281 18,500 * 33,000 46,000 Upstream of Oak Knoll Avenue 218 18,400 28,100 32,700 50,300 Near the City of St. Helena (Zinfandel Lane) 81.4 13,000 * 21,000 25,000 CAL OES SUBMITTAL - JUNE 2026
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Drainage
sq. Miles
Peak Discharge (cubic feet/second)
Flooding Source/Location 10-
percent
2-
percent
1-percent 0.2-
percent
At Dunweal lane 23 7,800 N/A 12,500 15,000
At State Highway 29 21.6 7,400 N/A 12,000 14,500
At upstream corporate limits 5.4 3,300 N/A 5,100 6,400
Salvador Creek
At confluence with Napa River * * * 3,910 *
At Big Branch Road 1.8 * * 3,213 *
Sulphur Creek
At confluence with Napa River to Sulphur Creek Tributary 9.2 * * 3,3301* Upstream of Sulphur Creek Tributary 7.6 * * 3,110 *
Sulphur Creek Tributary
At confluence with Sulphur Creek 1.1 * * 500 *
Tulucay Creek
At Soscol Avenue * 2,880 * 4,530 5,500
Upstream of Camille Creek * 2,050 * 3,250 4,050
Source: Table 5 Summary of Discharges from FEMA FIS Text, 2011 * Data not available
Warning Time
The type and rate of flooding experienced in the City of Napa varies. In general, warning times for floods can be between 24 and 48 hours. Seasonal notification for flooding can enhance awareness for citizens at risk, and, when communicated effectively, advance notification can reach target audiences on a large scale.

3.5.2.4 Earthquake Hazard
The City of Napa faces significant earthquake risk due to its location within the seismically active San Francisco Bay Area and its proximity to multiple active fault systems, including the West Napa Fault Zone.

Scenario-based analyses for this planning effort provides insight into the range of potential impacts from both regional and local seismic events, as illustrated in Figure 3-22 and Figure 3-23.

The Hunting Creek–Berryessa earthquake scenario (M7.1), shown in Figure 3-22 represents a large regional event affecting a broad portion of Napa County. Under this scenario, ground shaking across the City of Napa is generally characterized as moderate to strong, with some areas experiencing very strong shaking.

Because the source of the earthquake is more distant, the intensity of shaking is somewhat reduced compared to a local event, although it still affects a large portion of the community. Approximately threequarters of the City’s population and development are exposed to strong shaking, representing on the order 1 Flow rate reduction due to capacity restriction
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of nearly 60,000 residents and tens of thousands of parcels. A substantial portion of the City’s building and contents value, on the order of tens of billions of dollars, is also exposed. Critical infrastructure is widely affected, though not uniformly, indicating that while impacts would be extensive, they may vary across different parts of the city.

In contrast, the West Napa earthquake scenario (M6.7), shown in Figure 3-23, represents a more localized event occurring in close proximity to the City. Despite its lower magnitude, this scenario produces stronger and more uniform shaking across Napa. Nearly the entire City is subject to strong to very strong ground shaking, resulting in complete exposure of the population, built environment, and infrastructure systems.

This corresponds to nearly 80,000 residents, over 35,000 parcels, and the full extent of the City’s structural and contents value being subjected to damaging levels of shaking. All categories of critical infrastructure are similarly affected, reflecting the widespread and concentrated nature of impacts from a local seismic event.

Together, these scenarios demonstrate that earthquake risk in Napa is strongly influenced by proximity to the fault source. A larger regional earthquake produces widespread but somewhat variable impacts, while a smaller, nearby event results in more intense and uniform shaking across the entire city. In both cases, the expected impacts include damage to residential, commercial, and industrial buildings, disruption of transportation corridors such as State Route 29 and key arterial routes, and damage to essential utilities including water, wastewater, power, and communications systems.

Secondary hazards are also likely to contribute to overall earthquake risk. These include hazardous materials releases, fires following earthquakes, extended power outages, and reduced access for emergency response due to damage to roadways and bridges. Given the City’s role as a regional economic and transportation center, these impacts have the potential to extend beyond Napa and affect surrounding communities.

Liquefaction
Liquefaction represents a significant secondary earthquake hazard for the City of Napa due to local soil conditions, groundwater characteristics, and proximity to the Napa River and associated floodplain deposits. Liquefaction occurs when saturated, loose, fine-grained soils lose strength during ground shaking, causing the ground to behave as a fluid. As shown in Figure 3-24, areas of higher liquefaction susceptibility are concentrated in:
▪ Napa River corridor and adjacent floodplain;
▪ Downtown Napa and the Oxbow District;
▪ Southern portions of the City near the estuary and wetlands; ▪ Low-lying areas underlain by young alluvial and estuarine deposits.

These areas are characterized by shallow groundwater and unconsolidated sediments, increasing the likelihood of ground failure during moderate to strong shaking. Liquefaction can significantly amplify earthquake impacts by disrupting lifeline infrastructure and limiting emergency response access. In areas CAL OES SUBMITTAL - JUNE 2026
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with both high shaking intensity and susceptible soils, the potential exists for widespread ground deformation and infrastructure damage.

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Figure 3-22: Exposure Summary – City of Napa Earthquake Risk (M7.1 Hunting Creek–Berryessa) CAL OES SUBMITTAL - JUNE 2026
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Figure 3-23: Exposure Summary – City of Napa Earthquake Risk (M6.7 West Napa) CAL OES SUBMITTAL - JUNE 2026
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Figure 3-24: Exposure Summary – City of Napa Liquefaction Risk

3.5.2.5 Drought Hazard
The National Drought Monitor provides drought data and maps nationally and on a localized, watershed scale. The National Drought Monitor is the product of 11 agencies, including the NDMC, NOAA and USDA, CAL OES SUBMITTAL - JUNE 2026
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and is available at http://droughtmonitor.unl.edu/. The National Drought Monitor categorizes the level of drought from D0 through D4, with D4 being the highest “exceptional drought.” Table 3-14 depicts drought classifications and impacts from the level of drought occurrence in California, while Figure 3-25 shows a time series of the level of drought in Napa County from 2000 to 2026 according to the National Drought Monitor.

Drought is a recurring and long-term hazard for the City of Napa due to California’s Mediterranean climate, variable precipitation patterns, and increasing impacts from climate change. Periods of prolonged belowaverage rainfall, reduced snowpack in the Sierra Nevada, and higher temperatures can significantly affect regional water supplies, ecosystems, and community resilience. Although drought does not typically cause immediate physical damage like other hazards, its cumulative impacts can be widespread and long-lasting.

Napa relies on a combination of surface water and imported water supplies that are vulnerable to regional drought conditions. Extended drought periods can reduce available water supplies, increase demand during hotter and drier conditions, and place stress on water delivery systems. Drought conditions may also require implementation of mandatory water conservation measures, affecting residents, businesses, landscaping, and industrial operations.

Drought can exacerbate other natural hazards affecting the city. Dry conditions increase vegetation stress and fuel loads, elevating wildfire risk in surrounding grasslands and open space areas. Reduced soil moisture can also contribute to land subsidence, soil instability, and increased erosion during subsequent storm events. In addition, drought can degrade wetlands and riparian habitats along the Napa River and bayfront, reducing their natural flood attenuation and ecological functions.

Economic impacts of drought may include increased operational costs for businesses, reduced agricultural productivity in the surrounding region, and higher household expenses related to water use restrictions or rate adjustments. Vulnerable populations, including low-income households and elderly residents, may be disproportionately affected by higher utility costs and reduced access to cooling and water resources during extreme heat events associated with drought.

Climate change projections indicate that drought conditions in California are likely to become more frequent and severe, with longer dry periods punctuated by fewer but more intense storm events. These trends increase uncertainty in water supply reliability and place additional importance on long-term water resource planning, conservation, and resilience measures.

Table 3-14: Drought Classifications and Impacts
Category Description Possible Impacts
D0
Abnormally
Dry
▪ Soil is dry; irrigation delivery begins early
▪ Dryland crop germination is stunted
▪ Active fire season begins
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Category Description Possible Impacts
D1
Moderate
Drought
▪ Dryland pasture growth is stunted; producers give supplemental feed to cattle ▪ Landscaping and gardens need irrigation earlier; wildlife patterns begin to change ▪ Stock ponds and creeks are lower than usual
D2
Severe
Drought
▪ Producers increase water efficiency methods and drought-resistant crops ▪ Grazing land inadequate
▪ Fire season is longer, with high burn intensity, dry fuels, and large fire spatial extent, more fire crews on staff
▪ Lake- and river-based tourism declines; boat ramps close ▪ Trees are stressed; plants increase reproductive mechanisms; wildlife diseases increase
▪ Water temperatures increase; programs to divert water to protect fish begin ▪ River flows decrease; reservoir levels are low and banks are exposed D3
Extreme
Drought
▪ Federal water is not adequate to meet irrigation contracts; extracting supplemental groundwater is expensive
▪ Fire season lasts year-round; fires occur in typically wet parts of the state; burn bans are implemented
▪ Ski and rafting business are low; mountain communities suffer ▪ Low water levels impede fish migration and cause lower survival rates ▪ Wildlife encroaches on developed areas; little native food and water is available for bears, which hibernate less
▪ Water sanitation is a concern; reservoir levels drop significantly; surface water is nearly dry; flows are very low; water theft occurs
▪ Livestock need supplemental feed, cattle and horses are sold; little pasture remains ▪ Well and aquifer levels decrease; homeowners drill new wells D4
Exceptional
Drought
▪ Fire season is very costly; number of fires and areas burned are extensive ▪ Many recreational activities are affected
▪ Fields are left fallow; orchards are removed; vegetable yields are low; honey harvest is small; agricultural unemployment is high, food aid is needed ▪ Fish rescue and relocation begin; pine beetle infestation occurs; forest mortality is high; wetlands dry up; wildlife death is widespread; algae blooms appear ▪ Poor air quality affects health: greenhouse gas emissions increase as hydropower production decreases; West Nile outbreaks rise
▪ Water shortages are widespread; surface water is depleted; federal irrigation water deliveries are curtailed; water prices are extremely high; wells are dry, more and deeper wells are drilled; water quality is poor
Source: Adapted from U.S. Drought Monitor Drought Classifications and Impacts CAL OES SUBMITTAL - JUNE 2026
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Figure 3-25: Drought Severity Timeline 2000-2026

3.5.2.6 Severe Weather Hazard
Although the City of Napa benefits from a Mediterranean climate with some moderating marine influence from San Pablo Bay, the community remains vulnerable to a range of severe weather hazards, including high wind events, heavy rainfall, and winter storm systems. While these hazards may occur less frequently or with lower intensity than hazards such as wildfire or earthquake, they can still result in significant impacts to infrastructure, essential services, and vulnerable populations.

High Wind
High wind events represent a recurring severe weather hazard within the City of Napa, particularly during winter storm systems and offshore wind conditions. Winds may be funneled through the Napa Valley and surrounding hills, producing localized gusts that can cause damage across both urban and rural areas. These events have the potential to down trees and power lines, resulting in power outages, blocked roadways, and damage to residential and commercial structures.

High winds also contribute to broader hazard conditions. During dry periods, strong winds can exacerbate wildfire risk by increasing fire spread potential and carrying embers across developed areas. Within the built environment, structures with aging roofs, mobile homes, and outdoor facilities such as parks and schools may be particularly vulnerable to wind damage. Public safety concerns include falling trees and debris in residential neighborhoods and along major transportation corridors such as State Route 29 and Silverado Trail, where wind-related hazards can lead to traffic disruptions and accidents. Power outages associated with high wind events may also disrupt businesses, schools, and critical facilities.

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Heavy Rain
The City of Napa is also exposed to severe winter storm events that can produce heavy rainfall, localized flooding, and hazardous travel conditions. These storm systems are often associated with atmospheric river events that bring prolonged periods of precipitation, increasing the risk of riverine flooding along the Napa River and its tributaries, as well as urban drainage issues in developed areas.

Heavy rainfall can lead to saturated soils, increasing the likelihood of localized slope instability, erosion, and debris flows, particularly in hillside areas surrounding the valley floor. Storm events may also include lightning, short-duration intense rainfall, and occasional hail, all of which can contribute to property damage and public safety risks.

Severe weather impacts in Napa often cascade across multiple hazard areas. High winds and heavy rainfall are closely linked to power outages and infrastructure disruptions, which can disproportionately affect vulnerable populations, including older adults, medically dependent individuals, and residents without reliable access to backup power. Downed trees and localized flooding may block critical access routes, limiting mobility and emergency response capabilities.

As with other hazards, severe weather events may disproportionately affect lower-income households, renters, and populations with access and functional needs. These conditions underscore the importance of integrating severe weather considerations into emergency planning, infrastructure resilience, and equitable mitigation strategies.

3.5.2.7 Extreme Heat Hazard
The City of Napa’s climate is influenced by its location within the Napa Valley and proximity to San Pablo Bay, which typically provides some moderation of temperature extremes. However, despite this marine influence, the City is increasingly experiencing periods of elevated temperatures, particularly during late summer and early fall when offshore flow conditions reduce coastal cooling effects. In recent decades, Napa has seen an increase in the frequency, duration, and intensity of extreme heat events, a trend that is expected to continue under changing climate conditions.

Historical & Regional Context
Although Napa has historically experienced a Mediterranean climate characterized by warm, dry summers and mild coastal influence, recent regional heat waves have demonstrated the City’s growing vulnerability to extreme heat. Statewide events, including those in 2017 and 2020, resulted in prolonged periods of high temperatures across inland portions of the Bay Area, including Napa Valley. During these events, temperatures in Napa exceeded typical seasonal norms and, in some cases, approached or exceeded 100°F for multiple consecutive days.

Napa’s valley setting contributes to heat retention, particularly during periods of high pressure and low wind, when warm air becomes trapped and nighttime cooling is limited. These conditions can result in CAL OES SUBMITTAL - JUNE 2026
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extended heat events that persist over several days, increasing cumulative stress on residents, infrastructure, and natural systems. Unlike areas immediately adjacent to the bay, portions of Napa experience more pronounced temperature extremes due to reduced marine influence and localized topographic effects.

Climate projections indicate that the city is likely to experience a substantial increase in both the number of extreme heat days and warm nights over time. Extreme heat days, defined as those exceeding historically high temperature thresholds, are expected to become more frequent, while warm nights will reduce opportunities for overnight cooling, compounding heat-related stress on vulnerable populations.

According to the Cal-Adapt extreme heat days and warm nights tool using a medium emissions scenario (RCP 4.5), the City of Napa will likely experience a climate change-driven increase in extreme heat days from four days per year to 15 days per year by the end of the century. Over the same time period, the city is also likely to see an increase in warm nights from four per year to 42. Table 3-15 explains the extreme heat event thresholds for the City of Napa.

Table 3-15: Cal-Adapt Extreme Heat Thresholds
Term Cal-Adapt Definition
Thresholds for
City of Napa
Extreme
Heat Day
Defined as a day in a year when the daily maximum/minimum temperature exceeds the 98th percentile of daily maximum/minimum temperatures based on observed historical data from 1961-1990 between April and October.

99.2°F
Warm Night
Defined as a day in April through October when daily minimum temperature exceeds the 98th historical percentile of daily minimum temperatures, based on observed data from 1961-1990 between April and October.

59.3°F
Heat Wave Defined as four consecutive days or nights above the extreme heat / warm night threshold.
3 days ≥ 99.2°F
or 4 nights ≥

59.3°F
Source: Cal-Adapt Extreme Heat Days and Warm Nights Tool Impacts on Residents & Infrastructure
Extreme heat presents a range of risks to public health, infrastructure, and community services within the City of Napa. The most immediate impacts are related to heat-related illness, including heat exhaustion and heat stroke, particularly among vulnerable populations such as older adults, young children, individuals with pre-existing health conditions, outdoor workers, and households without adequate cooling.

The City’s demographic profile, including its aging population and residents with access and functional needs, increases sensitivity to prolonged heat events. In addition, disparities in housing quality and access to air conditioning can further exacerbate risk among lower-income households and renters.

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From an infrastructure perspective, extreme heat increases demand on the electrical grid due to higher cooling needs, raising the likelihood of service disruptions or rolling outages. Elevated temperatures can also degrade infrastructure, including roadways, rail systems, and utility components, while placing additional strain on heating, ventilation, and air conditioning systems in homes, businesses, and critical facilities. Public services and outdoor amenities, including parks and recreational programs, may also be affected during periods of extreme heat.

Cascading Effects
Extreme heat can contribute to and exacerbate other hazards within the City of Napa. Prolonged high temperatures dry vegetation and increase wildfire risk in surrounding areas, while also contributing to degraded air quality, particularly during regional wildfire events. Heat can also intensify drought conditions by increasing evaporation rates and water demand, placing additional stress on local water resources.

Social and economic impacts are also associated with extreme heat. Households with limited financial resources may face challenges in maintaining adequate cooling or absorbing increased utility costs during prolonged heat events. These factors can contribute to disproportionate impacts on vulnerable populations and increase the need for targeted outreach and support.

3.5.2.8 Climate Change Hazard
Average annual temperatures across most of California have already increased by more than 1°F, with some areas experiencing rises of over 2°F when comparing the 1901 to 1960 average to that of 1986 to 2016. Daily maximum temperatures—a key indicator of extreme heat—are projected to increase by 4.4°F to 5.8°F by 2050 and by 5.6°F to 8.8°F by 2100. Heat waves that impact public health, known as heat-health events, are also expected to intensify across the state. By 2050, these events are projected to last up to two weeks longer in the Central Valley and occur four to ten times more often in the Northern Sierra region (California Natural Resources Agency, 2022).

California is already experiencing significant impacts from climate change, including prolonged drought, a lengthened wildfire season, increased coastal flooding and erosion, and widespread tree mortality. The state has observed rising average temperatures, more extreme heat days, fewer cold nights, a longer growing season, and shifts in the water cycle, with less winter precipitation falling as snow. In addition, summertime fog has declined by approximately 33%, and both snowmelt and rainwater runoff are occurring earlier in the year (Cal OES, 2018).

Long-term trends indicate a 12% to 20% decline in fog across California from 1900 through projections to 2070. Climate experts suggest that warming temperatures reduce the ability of air masses to cool enough to produce fog, which plays a critical role in supporting California’s ecosystems (Grantham, Teodore; University of California, Berkeley, 2018).

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The City of Napa is increasingly vulnerable to the long-term impacts of climate change, which function as hazard multipliers across the Napa Valley and broader North Bay region. Napa’s location within an inland valley, combined with its proximity to San Pablo Bay and surrounding upland areas, creates a complex climate setting that is sensitive to shifts in temperature, precipitation patterns, and seasonal variability.

Projected changes in these conditions are expected to intensify existing hazards, including flooding, drought, extreme heat, and wildfire.

Napa’s valley topography contributes to localized climate effects, particularly during extreme heat events.

Warm air can become trapped within the valley, reducing nighttime cooling and prolonging heat exposure compared to nearby coastal areas. As temperatures continue to rise, these conditions are expected to increase both the frequency and duration of heat events, placing additional stress on vulnerable populations such as older adults, children, outdoor workers, and residents without access to adequate cooling. Increased heat also drives higher energy demand, placing strain on the electrical grid and increasing the likelihood of service disruptions.

Sea Level Rise
The City of Napa is located at the southern end of Napa County adjacent to the Napa River and in proximity to the San Pablo Bay, making it one of the few jurisdictions in the county directly exposed to sea level rise and tidal flooding hazards. Although much of Napa County is inland and not affected by coastal processes, Napa’s proximity to the Bay places some southern portions of the city at risk from rising sea levels, storm surge, and changes in tidal dynamics.

Sea level rise can lead to increased frequency and extent of tidal flooding, particularly in low-lying areas near the Napa River, wetlands, and shoreline zones. Areas that currently experience occasional flooding during high tides or storm events may be inundated more frequently as sea levels rise. In addition, higher baseline water levels can reduce the capacity of drainage systems to discharge stormwater, potentially leading to compound flooding during periods of heavy rainfall combined with high tides.

Critical infrastructure located near the Bay and river corridors may also be vulnerable to sea level rise. This includes transportation corridors, stormwater systems, wastewater infrastructure, and utilities, which may be affected by periodic inundation, corrosion, or reduced functionality over time. Wetlands and natural shoreline features may provide some buffering capacity, but they may also be impacted by rising water levels and changes in sediment dynamics.

Sea level rise may also contribute to secondary impacts, including saltwater intrusion into groundwater or soils, degradation of habitats, and increased maintenance needs for levees. In areas where development is located along tidal waterways, long-term exposure to rising water levels may affect land use, infrastructure planning, and property values.

Climate change projections for the San Francisco Bay Area indicate that sea levels are expected to continue rising over the coming decades, increasing the likelihood of both chronic tidal flooding and more severe CAL OES SUBMITTAL - JUNE 2026
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impacts during storm events. As a result, the City of Napa may face increasing pressure to plan for adaptation strategies, including improvements to flood protection infrastructure, enhancement of natural buffers such as wetlands, and integration of sea level rise considerations into future development and capital improvement planning.

Precipitation, Storms & Flooding
Although total annual precipitation may not significantly increase, climate projections indicate that rainfall is more likely to occur in fewer, more intense storm events. These high-intensity storms, often associated with atmospheric river systems, increase the risk of riverine flooding along the Napa River as well as localized flooding in urban areas with constrained drainage systems.

Intense rainfall following extended dry periods can also increase the risk of erosion, localized slope instability, and debris flows, particularly in hillside areas surrounding the valley floor and along transportation corridors. These conditions can impact critical infrastructure, damage roadways, and disrupt emergency access. In addition, sea level rise combined with higher peak flows in the Napa River and its tributaries may exceed existing system capacity during extreme events, contributing to flooding beyond currently mapped floodplain boundaries.

Drought & Water Reliability
Climate change is expected to result in more frequent and prolonged drought conditions across Napa County. While the City of Napa benefits from a combination of local and regional water sources, extended dry periods can reduce water availability, increase demand, and place stress on both surface water and groundwater systems. Reduced precipitation and earlier snowmelt in upstream watersheds may affect reservoir storage and seasonal water supply reliability.

Drought conditions also have broader environmental and hazard implications. Reduced soil moisture and vegetation stress increase susceptibility to wildfire in surrounding areas, while also affecting urban landscaping and tree canopy health within the city. Prolonged dry conditions may also impact local creeks and riparian systems, which play an important role in stormwater conveyance, habitat, and groundwater recharge.

Wildfire & Vegetation Change
Climate-driven increases in temperature and changes in precipitation patterns are expected to extend the wildfire season and increase fire risk in areas surrounding the City of Napa. While much of the city is urbanized, it is bordered by wildland and open space areas that are susceptible to wildfire. Fires in surrounding areas can affect the city through evacuation impacts, degraded air quality, and strain on emergency services.

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Changes in vegetation patterns, including increased tree mortality and shifts in species composition, may contribute to higher fuel loads over time. Even when wildfire does not directly impact the City, smoke and poor air quality can have significant public health consequences, particularly for sensitive populations.

Cascading Effects
Climate change amplifies interactions between hazards, creating compounding risks for the City of Napa.

Extreme heat can worsen drought conditions and increase wildfire potential, while drought-stressed landscapes are more susceptible to erosion during intense storm events. Severe storms may damage infrastructure already stressed by heat or aging conditions, while flooding can disrupt transportation and utility systems needed for emergency response.

These cascading effects underscore the importance of integrating climate considerations into hazard mitigation planning, infrastructure investment, emergency preparedness, and community outreach. As climate conditions continue to evolve, proactive planning will be critical to reducing long-term risk and enhancing community resilience.

Climate Change Impacts & Vulnerable Populations
Climate change is expected to exacerbate many of the natural hazards affecting the City of Napa, increasing risks to populations that already face social, economic, or physical vulnerabilities. Rising temperatures, more extreme precipitation events, prolonged drought, and more frequent extreme heat events are projected to intensify existing hazard conditions and create additional challenges for public health, safety, infrastructure, and emergency response. These changes will also place increased demand on water, energy, and lifeline systems, requiring greater operational flexibility to maintain service to critical facilities and vulnerable residents.

Certain populations in Napa are more likely to experience disproportionate impacts from climate-related hazards. Older adults, individuals with disabilities, low-income households, renters, unhoused individuals, and households with limited English proficiency may have reduced capacity to prepare for, respond to, and recover from hazard events. These groups may face barriers related to mobility, access to transportation, financial resources, housing stability, and timely access to emergency information, increasing their overall vulnerability.

Extreme heat presents a growing risk to vulnerable populations, particularly seniors, medically fragile individuals, outdoor workers, people experiencing homelessness, and households without reliable air conditioning. Climate projections indicate that extreme heat events will become more frequent, intense, and prolonged, increasing the likelihood of heat-related illness and exacerbating existing health conditions.

These events also increase demand on energy systems, potentially straining infrastructure and affecting the City’s ability to maintain reliable service during peak conditions.

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Flooding hazards, which are concentrated along the Napa River and its tributaries, disproportionately affect residents and workers located within mapped flood hazard areas. More than 12,000 residents and thousands of parcels are located within these zones, with exposure including mobile home parks and lower-income neighborhoods that may face greater challenges in recovery. In addition, unhoused individuals living along the Napa River and creeks face heightened life-safety risks during flood events due to barriers in receiving warnings and evacuating safely. Flooding also threatens critical facilities, lifeline infrastructure, and transportation systems, which can disrupt access to essential services.

Drought and water supply challenges are expected to intensify under changing climate conditions.

Increasingly frequent and severe droughts will require long-term demand management and efficient use of water resources to maintain supply reliability. These conditions can increase utility costs and place additional burdens on vulnerable households, particularly those with limited financial resources. Reduced water availability may also affect local economic activity, including agriculture and tourism, and contribute to vegetation stress that increases wildfire risk.

Wildfire and smoke impacts are also expected to increase in frequency and duration, affecting Napa through degraded air quality, public safety power shutoffs, and disruptions to daily activities and economic activity.

Vulnerable populations, including individuals with respiratory conditions, older adults, children, and outdoor workers, are particularly sensitive to smoke exposure. Limited access to clean indoor air, filtration systems, or protective equipment can further increase health risks.

Severe weather events, including heavy rainfall and high winds, may become more frequent and intense, contributing to localized flooding, infrastructure damage, and power outages. These events can disrupt transportation networks, block evacuation routes, and limit emergency response capabilities. Power outages associated with high winds and public safety shutoffs may further impact vulnerable populations who rely on electricity for medical equipment or basic needs.

Climate change may also increase the frequency and duration of poor air quality events and compound risks across multiple hazard types. These cascading effects highlight the importance of integrating climate adaptation, public outreach, and equitable mitigation strategies into planning efforts to reduce long-term risk and improve community resilience.

Hazard Problem Statements
As part of the mitigation action identification process, the Planning Committee for each jurisdiction identified areas of concern (aka problem statements) for their respective facilities based on the risk assessment and vulnerability analysis, utilizing the RAMP mapping and static snapshot maps. Problem statements focused on the impact, victim, or threat that the hazard could create in the jurisdiction, as described in Table 3-16. Identifying common issues and weaknesses through these problem statements assisted the planning group in understanding the realm of resources needed for mitigation.

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The goal is to have at least one mitigation action for every problem statement. Projects or actions have been developed to mitigate each problem identified. See Table 3-18 for a full list of mitigation actions and corresponding problem statements that they address. Each problem statement is coded with a problem number for cross-referencing between Table 3-16 and Table 3-18 Table 3-16: City of Napa Hazard Problem Statements
Problem No. Hazard Area of
Concern
Primary
Agency
Problem Description Related MA
ps-AH-CN-47 All Hazard Threat City of Napa The existing Emergency Operations Center (EOC) and associated technology are
undersized and lack the redundancy, and
multi-agency workspace needed to support
coordinated response and recovery for large,
multi-day hazard events.
ma-AH-CN-1, maAH-CN-4, ma-AHCN-13, ma-AHCN-0, ma-AH-CN8 ps-CC-CN-1 Climate
Change
Impact City of Napa Some community members remain unaware of the City’s climate adaptation and mitigation
efforts and of actions they can take to reduce
risk (e.g., home weatherization, defensible
space), limiting participation in resilience
programs and behavior change.
ma-AH-CN-3, maAH-CN-5
ps-CC-CN-4 Climate
Change
Victim City of Napa Climate change is expected to increase the frequency and severity of extreme heat,
drought, severe weather, wildfire and smoke,
and flooding in and around Napa,
compounding impacts on vulnerable
populations and lifeline services.
ma-CC-CN-51,
ma-AH-CN-0, maAH-CN-3, ma-AHCN-7, ma-AH-CN8, ma-WF-CN-43, ma-WF-CN-41,
ma-FL-CN-24,
ma-EW-CN-58,
ma-FL-CN-28,
ma-DR-CN-16
ps-CC-CN-19 Climate
Change
Impact City of Napa The compounding effects of sea level rise, king tide, and severe weather events may increase
the frequency and severity of flooding.
ma-FL-CN-23,
ma-FL-CN-24,
ma-FL-CN-27,
ma-FL-CN-28,
ma-FL-CN-29,
ma-AH-CN-3
ps-DF-CN-41 Dam Failure Threat City of Napa Dam-failure risk and response planning may not be fully integrated into City and County
emergency operations plans, resulting in
unclear roles, evacuation priorities, and
communication protocols for a multijurisdictional dam-break event. ma-DF-CN-15,
ma-DF-CN-52,
ma-AH-CN-0, maAH-CN-8
ps-DF-CN-43 Dam Failure Victim City of Napa Tens of thousands of residents and dozens of critical facilities in the City of Napa are located
within dam inundation areas associated with
Hennessey, Conn, Bell Canyon, Milliken, and
Soda Canyon dams, creating life-safety and
displacement risks in a failure scenario.
ma-DF-CN-52,
ma-DF-CN-15,
ma-CC-CN-51,
ma-AH-CN-3, maAH-CN-7
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Problem No. Hazard Area of
Concern
Primary
Agency
Problem Description Related MA
ps-DR-CN-29 Drought Threat City of Napa Increasingly frequent and severe droughts, are accounted for in the City’s Urban Water
Management Plan including a 10% reduction in
water supplies starting in 2035. Long-term
demand management and maximizing use of
water resources will be necessary to ensure
water supply reliability, and maintain service
levels.
ma-DR-CN-16
ps-DR-CN-31 Drought Impact City of Napa Drought impacts to the Napa Valley American Viticultural Area (AVA) can reduce agricultural
productivity, degrade landscape quality, and
negatively affect Napa’s tourism- and
agriculture-based economy.
ma-AH-CN-3, maDR-CN-54, maDR-CN-16
ps-DR-CN-33 Drought Victim City of Napa The City provides bilingual education and outreach to community members but some
water customers may lack action on reducing
water consumption and free conservation
incentives, particularly during drought
emergencies, leading to uneven participation
and higher burdens on vulnerable households.
ma-DR-CN-54,
ma-AH-CN-3, maDR-CN-16
ps-EQ-CN-5 Earthquake Impact City of Napa Community assets and critical facilities, including schools, elder care facilities, bridges,
historic downtown structures, and small
businesses, may be vulnerable to strong
shaking, threatening long-duration closures,
economic losses, and loss of cultural and
historic resources.
ma-EQ-CN-18,
ma-EQ-CN-18,
ma-AH-CN-8, maEQ-CN-20
ps-EQ-CN-6 Earthquake Impact City of Napa Some of the City’s water, wastewater, stormwater, and electric systems may lack full
redundancy and backup power at key nodes,
which may increase the risk of lifeline
disruption and limited emergency response
capacity following a major earthquake.
ma-EQ-CN-20,
ma-AH-CN-0
ps-EQ-CN-7 Earthquake Victim City of Napa All Napa residents live in severe shaking zones associated with the West Napa Fault
scenario, with renters, mobile home residents,
seniors, and lower-income households facing
disproportionate risk of injury, displacement,
and loss of housing stability.
ma-EQ-CN-17,
ma-EQ-CN-56,
ma-AH-CN-3, maEQ-CN-18
ps-FL-CN-20 Flood Impact City of Napa Multiple critical facilities, including fire stations, communications towers, the
Corporation Yard, and other assets, are located
within the 100-YR floodplain and remain
exposed to riverine and backwater flooding as
the Napa River Flood Project continues to be
implemented.
ma-FL-CN-49,
ma-FL-CN-24,
ma-FL-CN-23,
ma-AH-CN-13,
ma-AH-CN-8, maFL-CN-28
ps-FL-CN-22 Flood Victim City of Napa More than 12,500 residents and approximately 4,500 parcels with improvements valued at $1.6
billion lie within mapped flood hazard zones;
flood risk is concentrated along the Napa River
and tributaries, with mobile home parks and
lower-income neighborhoods facing
disproportionate consequences.
ma-FL-CN-49,
ma-FL-CN-23,
ma-FL-CN-62,
ma-AH-CN-3, maCC-CN-51, maAH-CN-7, ma-FLCN-28
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Problem No. Hazard Area of
Concern
Primary
Agency
Problem Description Related MA
ps-FL-CN-23 Flood Threat City of Napa Outdated flood hazard mapping and limited public awareness of flood risk and property
owner drainage maintenance responsibilities
contribute to flood exposure and can hinder
risk-reduction investments by property
owners.
ma-FL-CN-30,
ma-FL-CN-23,
ma-FL-CN-28
ps-FL-CN-27 Flood Victim City of Napa Unhoused residents living in encampments along the Napa River and creeks face barriers
to receiving warnings and evacuating quickly
during flood events, increasing life-safety risks
and complicating emergency response.
ma-AH-CN-7, maAH-CN-3
ps-CC-CN-0 High Heat Impact City of Napa The City’s water and energy systems will require additional capacity and operational
flexibility to serve increased demand during
more frequent and longer extreme heat events,
while also maintaining service to critical
facilities and vulnerable residents.
ma-DR-CN-16
ps-CC-CN-2 High Heat Victim City of Napa Seniors, residents of mobile home parks, medically fragile individuals, people
experiencing homelessness, households
without reliable air conditioning, and outdoor
workers face disproportionate health and
safety risks during extreme heat events.
ma-AH-CN-3, maCC-CN-51, maAH-CN-7
ps-CC-CN-17 High Heat Threat City of Napa Climate change is expected to lead to increases in the frequency, intensity, and
duration of extreme heat events, which are
likely to increase the risk of heat-related
illness and exacerbation of existing chronic
health conditions.
ma-CC-CN-51,
ma-CC-CN-14,
ma-AH-CN-7
ps-EW-CN-34 Severe
Weather
Impact City of Napa Heavy rain and atmospheric river events may cause localized street flooding and hazardous
travel conditions at known drainage
bottlenecks due to undersized culverts,
blocked storm drains, and limited detention
capacity.
ma-FL-CN-49,
ma-AH-CN-13,
ma-AH-CN-3, maFL-CN-24
ps-EW-CN-35 Severe
Weather
Threat City of Napa Climate change is expected to increase the frequency and severity of high wind and
atmospheric river events in the City of Napa
and surrounding areas.
ma-EW-CN-58,
ma-FL-CN-24
ps-EW-CN-36 Severe
Weather
Impact City of Napa Backup generators are needed to maintain continuity of City utilities and services during
severe weather events.
ma-AH-CN-57,
ma-EW-CN-58
ps-EW-CN-39 Severe
Weather
Impact City of Napa Increasingly frequent high-wind events and PSPS outages may down trees and utility lines,
exacerbate wildfire risk, block evacuation
routes, and disrupt power, communications,
and other essential services across the city.
ma-WF-CN-45,
ma-AH-CN-8, maEW-CN-58
ps-WF-CN-11 Wildfire Impact City of Napa Napa’s wastewater treatment facility, raw water conveyance systems, communication
facilities, and watershed lands, including the
Lake Hennessey drainage area, are vulnerable
to wildfire and post-fire erosion, threatening
water quality, supply reliability, and critical
communications.
ma-WF-CN-43,
ma-WF-CN-41
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