Calistoga City Council
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Table 5-9: Town of Yountville 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
Yountville Planning
Team
Breakout Meeting #1
November 6, 2025
▪ 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
Yountville Planning
Team
Breakout Meeting #2
November 19, 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

5.3.1 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 agencies. These comments were incorporated into the Town’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.

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5.4 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 Town of Yountville previously participated and maintained a Hazard Mitigation Plan, which guided resilience planning and hazard mitigation actions at the Town level.

Yountville is updating their current plan on a county wide level. This integration reflects the Town’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, Yountville 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, Yountville has strengthened its capacity to prepare for, withstand, and recover from disasters while continuing to protect its unique community character.

5.4.1 Mitigation Activities
The town 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 Yountville’s ability to effectively plan, fund, and execute measures that protect its residents and infrastructure.

In addition, Yountville 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 Town aligns with best practices to build resilience against natural disasters.

This ongoing effort is a testament to the Town’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 Town’s mitigation efforts remain ongoing or in the pipeline. These actions, ranging from infrastructure upgrades to community outreach initiatives, represent the Town’s proactive approach to addressing hazards as resources become available.

Recognizing constraints such as limited funding, staffing, and shifting priorities, the Town 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 Town’s updated hazard mitigation goals. Adjustments to previous mitigation actions are documented as part of the Town of Yountville’s Mitigation Action Plan Table 5-16, and more specific status updates are provided in Table 5-17.

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

The following success story highlights ongoing efforts to address key hazards such as wildfire-related power disruptions, infrastructure vulnerability, and climate change impacts. Collectively, this initiative demonstrates the Town’s ability to move from planning to implementation by leveraging partnerships, securing federal funding, and advancing innovative projects that provide long-term risk reduction benefits to the community.

Energy Resilience through Microgrid Development
The Town of Yountville has advanced a Resiliency Microgrid Project to improve energy reliability and continuity of operations during emergency events, including wildfires and public safety power shutoffs. In April 2026, the Town secured $250,000 in federal funding to support the development of the microgrid, demonstrating a strong commitment to proactive hazard mitigation and climate resilience.

The microgrid project is designed to integrate renewable energy sources and battery storage systems to create a localized power network capable of operating independently from the traditional electrical grid.

During grid outages caused by wildfire events, extreme weather, or other disruptions, the microgrid will provide reliable, uninterrupted power to support critical community functions and maintain essential services.

This project directly addresses the Town’s vulnerability to power disruptions associated with wildfire risk and regional grid instability, which have increasingly affected communities throughout Napa County. By enhancing local energy independence, the microgrid reduces reliance on external infrastructure and strengthens the Town’s ability to maintain operations during emergency conditions.

In addition to improving emergency preparedness, the project supports broader sustainability and climate adaptation goals by incorporating clean energy technologies and reducing long-term environmental impacts. The microgrid represents a forward-looking, infrastructure-based mitigation strategy that enhances resilience, protects public safety, and ensures continuity of essential services for residents and businesses.

This effort highlights the Town of Yountville’s ability to leverage external funding, implement innovative solutions, and translate hazard mitigation planning into tangible, long-term resilience investments.

Updated Safety Element
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evacuation planning, siting critical infrastructure outside hazard zones where feasible, and maintaining participation in the Napa County MJHMP update cycle.

5.5 Risk Assessment
This section focuses on profiling hazards specific to the Town of Yountville 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 town, and information on town-specific differences in hazard vulnerability across the planning area. It also identifies total Town assets at risk, including people, property, and critical facilities and infrastructure within the Town. 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.

5.5.1 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 Town of Yountville’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 town. Table 5-10 provides a crosswalk of hazards identified in select planning documents, including the 2020 Napa County MJHMP, the Town of Yountville 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 Town of Yountville and which ones were not.

The internal planning group then ranked hazards based on their probability of affecting Town of Yountville and potential impacts on the community. Figure 5-10 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 Town’s vulnerability to specifically identified hazards.

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Table 5-10: Town of Yountville Document Review of Potential Hazards Hazard 2020 Napa County
MJHMP
Town of Yountville 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 5-10: Town of Yountville 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 town’s Planning Team, before further refinement, are identified in the county’s completed matrix in Figure 5-10. Table 5-11 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 5-11: Town of Yountville Hazards Prioritization Summary Hazard Priority Explanation
Earthquake / Liquefaction High Profiled in Volume 1, Section 3.3.4, and Section 5.5.2.2 in this annex, including Liquefaction
Wildfire High Profiled in Volume 1, Section 3.3.1, and Section 5.5.2.1 in this annex Flood Medium Profiled in Volume 1, Section 3.3.2, and Section 5.5.2.3 in this annex Levee Failure -
Profiled in Volume 1, Section 3.3.2; not a priority due to low probability and impact potential
Extreme Weather / Storms High
Profiled in Volume 1, Section 3.3.5, and Section 5.5.2.7 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 5.5.2.5 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 5.5.2.4 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 - 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 5.5.2.8 in this annex Dam Failure Medium Profiled in Volume 1, Section 3.3.3, and Section 5.5.2.6 in this annex CAL OES SUBMITTAL - JUNE 2026
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5.5.2 Vulnerability to Specific Hazards
Assessing vulnerabilities exposes the unique characteristics of individual hazards and begins the process of narrowing down which areas within the town 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 town’s planning group estimated vulnerable populations, properties, and assets, and potential losses. In addition, the exposure of town 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 Town’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 Town of Yountville, some of which encompass sub hazards such as Liquefaction and Heavy Rain Wildfire
SECTION 5.5.2.1
Earthquake
SECTION 5.5.2.2
Flood
SECTION 5.5.2.3
Extreme Heat
SECTION 5.5.2.4
Drought
SECTION 5.5.2.5
Dam Failure
SECTION 5.5.2.6
Severe Weather
SECTION 5.5.2.7
Climate Change
SECTION 5.5.2.8
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Wildfire Hazard
Wildfire risk in the Town of Yountville is primarily concentrated along the western edge of the community, where developed areas interface with open space, and the Mayacamas Mountains. The wildfire risk exposure map, Figure 5-11, shows that portions of the Town and surrounding Sphere of Influence are located within Moderate and High Fire Hazard Severity Zones, particularly in areas adjacent to undeveloped land and wildland vegetation.

High wildfire hazard areas are also present along portions of the Town’s western edge near the Mayacamas Mountains. Seasonal drying of vegetation and wind conditions can exacerbate localized wildfire risk, particularly during extended drought periods. The eastern portion of Yountville has no wildfire hazard because it is on the Napa Valley floor away from any hillsides.

The exposure summary associated with the wildfire risk map indicates that, within current mapped hazard areas, there are no permanent residential populations, parcels, or critical infrastructure classified within the Very High Fire Hazard Severity Zone inside town limits. As a result, population exposure, parcel exposure, and critical infrastructure exposure rates within the highest hazard category are reported at 289 persons and 26 parcels. This reflects Yountville’s relatively urbanized development pattern and limited extent of very high-risk wildfire terrain within incorporated boundaries.

Despite the small amount of Very High Fire Hazard Severity Zones within the Town, wildfire remains an important planning consideration due to proximity to higher-risk areas outside town limits, regional wildfire activity, and secondary impacts such as smoke exposure, power shutoffs, transportation disruptions, and evacuation demands. 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 Yountville.

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Figure 5-11: Exposure Summary – Yountville Wildfire Risk CAL OES SUBMITTAL - JUNE 2026
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Earthquake Hazard
The Town of Yountville 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 Town 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 Town.

Under the Hunting Creek–Berryessa M7.1 scenario (Figure 5-12), ground shaking across Yountville is generally characterized as Very Strong and Severe (Modified Mercalli Intensity [MMI] VII – VIII). Exposure summaries indicate that approximately 2,900 residents, more than 1,250 parcels, and nearly $613 million in building improvement value and $443 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 5-13, represents an even more impactful event for Yountville. Under this scenario, 100 percent of the Town’s population, parcels, and assessed parcel value are exposed to Very Strong to Severe (MMI VII - VIII). Exposure summaries indicate that approximately 3,400 residents, 1,300 parcels, and nearly $617 million in building improvement value and $445 million in content value fall within these intensity ranges.

While exposure summaries indicate no population, parcels, or critical infrastructure located in the highest modeled intensity categories for this scenario within Town 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 Highway 29 and Silverado Trail; and damage to utilities including water, wastewater, power, and communications systems.

Secondary earthquake hazards also present a concern for Yountville. 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 Town’s strategic location in the Napa Valley, such disruptions could have regional economic and public safety consequences.

Liquefaction
Liquefaction represents a significant secondary earthquake hazard for the Town of Yountville due to local soil conditions, groundwater characteristics, and proximity to the Napa River. 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, CAL OES SUBMITTAL - JUNE 2026
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loss of bearing capacity, and damage to buildings, roadways, and buried utilities. While liquefaction is a consideration in hazard mitigation planning, it is not profiled as a standalone hazard but addressed as a secondary earthquake effect.

Areas of Yountville with higher liquefaction susceptibility are generally located in low-lying portions of the Town underlain by young alluvial sediments. These conditions are most prevalent near the Napa River, where shallow groundwater levels increase the likelihood of liquefaction during moderate to strong earthquake shaking (Figure 5-14). In these areas, even structures designed to withstand seismic forces may experience damage if foundations or supporting soils lose stability.

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. Industrial and 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 Yountville 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 Town’s broader functionality and recovery following a major earthquake.

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Figure 5-12: Exposure Summary – Yountville Earthquake Risk (M7.1 Hunting Creek–Berryessa) CAL OES SUBMITTAL - JUNE 2026
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Figure 5-13: Exposure Summary – Yountville Earthquake Risk (M6.7 West Napa) CAL OES SUBMITTAL - JUNE 2026
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Figure 5-14: Exposure Summary – Yountville Liquefaction Risk CAL OES SUBMITTAL - JUNE 2026
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Flood Hazard
Flooding is a natural hazard for the Town of Yountville due to its location near the Napa River. Portions of the Town are subject to riverine flooding, particularly during major precipitation events, high tides, or conditions influenced by sea level rise. Flood hazard areas within Yountville are primarily concentrated along the Napa River, as well as along localized drainage corridors.

The FEMA Flood Risk Exposure map, Figure 5-15, shows areas within the 100-year (1-percent annual chance) and 500-year (0.2-percent annual chance) floodplains, including mapped floodway areas and zones protected by levees. These flood-prone areas reflect the combined influence of river overflow, tidal backwater effects, 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 approximately 1,620 residents, representing around 7% of the town’s population, are located within mapped flood hazard areas. In addition, over 200 parcels (about 3% of all parcels) are exposed to flooding, with an estimated $128 million in building improvement value and a similar amount in contents value at risk. While no essential facilities or hazardous materials sites are located within the mapped flood hazard areas, several transportation and lifeline facilities intersect flood-prone zones, highlighting the potential for access disruptions and service interruptions during flood events.

Flooding in Yountville 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, sediment deposition, and degradation of wetlands and shoreline infrastructure.

Climate change is expected to increase flood risk in Yountville over time. Projections for sea level rise, more intense precipitation events, and higher storm surge heights may expand flood extents, increase flood depths, and reduce the effectiveness of existing levees and 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 Town of Yountville has participated in the NFIP since 1980 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 (Yountville Municipal Code Chapter 15, Division 2). 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 town 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 town’s floodplain regulations are assigned to the floodplain administrator.

The Town of Yountville 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 5-12 for more information on the town’s policies and historic flood insurance claims.

Table 5-12: Town of Yountville National Flood Insurance Program Information Town of Yountville NFIP Status and Flood Insurance Statistics NFIP Status Participating Since 3/18/1980
Community Identification (CID) 060209
CRS Class (Entry Date) N/A
Policies in Force (Total Coverage) 30 Policies ($9,478,000 Coverage) Policies Inside SFHA / Outside SFHA 15 Inside / 15 Outside Policies in Coastal Zones (Total Coverage) N/A
Total Claims (Total Paid) 22 Claims ($122,488 Paid)
Repetitive Loss (RL) / Severe Repetitive Loss (SRL) Properties 4 RL / 0 SRL Repetitive Loss Payments $83,793
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 Town of Yountville is the Napa River and its tributaries. Riverine flooding from the Napa River and its tributaries is the primary driver of mapped flood risk in Yountville.

During major storm events, high river flows can overtop banks or exceed channel capacity.

Localized flooding from creeks, drainage channels, and stormwater systems occurs within the town but generally represents a secondary source compared to the combined riverine and tidal flooding associated with the Napa River system.

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Figure 5-15: Exposure Summary –Yountville Flood Risk (FEMA Zones) CAL OES SUBMITTAL - JUNE 2026
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Extreme Heat Hazard
The town’s inland valley location and reliance on outdoor agricultural labor make it particularly sensitive to rising temperatures and more frequent extreme heat days. While the bay influence of San Pablo Bay provides some natural moderation, 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. In Yountville, outdoor agricultural 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 town’s population exposure is compounded by socioeconomic factors. Some households in Yountville 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.

The frequency of extreme heat days is projected to rise significantly across inland Napa County by midcentury. According to Cal-Adapt, Yountville will likely experience a climate change-driven increase in extreme heat days above 101.2°F from three days per year to 16 days per year by the end of the century under a medium emissions scenario (RCP 4.5). Over the same time period, the town is also likely to see an increase in warm nights above 60.6°F from four per year to 36.

For Yountville, this means disproportionate impacts on agricultural workers in the Napa Valley as well as low-income households 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.

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 5-13 depicts drought classifications and impacts from the level of drought occurrence in California, while Figure 5-16 shows a time series of the level of drought in Napa County from 2000 to 2025 according to the National Drought Monitor.

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Drought is a recurring and long-term hazard for the Town of Yountville 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.

Yountville 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 Yountville. 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 5-13: 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
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Category Description Possible Impacts
▪ 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 5-16: Drought Severity Timeline 2000-2024
Dam Failure Hazard
Dam failure is a lower-probability but high-consequence hazard for the Town of Yountville due to its downstream location from several reservoirs. Dam failure refers to the partial or complete structural failure of an upstream dam, resulting in the uncontrolled release of stored water. Although there are no major dams located within Yountville town limits, failure of an upstream dam could generate rapid downstream flooding affecting portions of the Town.

Potential causes of dam failure include extreme precipitation events that exceed design capacity, seismic activity, internal erosion or piping, slope instability, aging infrastructure, or operational issues. Earthquakes are a particular concern in Napa County, where strong ground shaking could compromise dam embankments, spillways, or outlet works. Climate change may also increase stress on dam systems by intensifying storm events and altering hydrologic conditions.

Dam failure events differ from typical riverine flooding in that floodwaters may arrive with little warning, high velocity, and significant destructive force, greatly increasing risks to life safety, structures, transportation corridors, and utilities. Because warning times may be limited, emergency preparedness, public awareness, and evacuation planning are critical components of risk reduction.

Dam safety oversight, inspection, and emergency action planning are managed at the state and regional levels, including by the California Department of Water Resources and the California Division of Safety of Dams. These agencies work with dam owners and local jurisdictions to monitor dam conditions and coordinate emergency notification procedures.

Dam inundation describes the geographic areas that could be flooded as a result of a dam failure upstream.

Inundation mapping identifies where floodwaters would travel and accumulate if a failure were to occur.

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The Dam Inundation Exposure map, Figure 5-17, shows that inundation zones in Yountville are primarily concentrated along the western portion of the Town near the Napa River corridor and other low-lying terrain. These areas reflect natural flow paths where floodwaters would be conveyed downstream under a dam failure scenario.

Exposure analysis indicates that approximately 600 residents and close to 100 parcels fall within these areas, with an estimated $94 million in building improvement value and $83 million in contents value exposed. Several high-potential-loss facilities and transportation and lifeline facilities are also located within inundation zones, underscoring the potential for service disruptions and access limitations during a dam-related flood event.

Dam inundation flooding can result in deep, fast-moving water capable of causing severe structural damage, roadway washouts, utility failures, and long-term economic disruption. Because these areas may experience flooding rapidly following a dam failure, evacuation and emergency response may be challenging, particularly in locations with limited access routes.

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Figure 5-17: Exposure Summary – Yountville Dam Inundation Zone CAL OES SUBMITTAL - JUNE 2026
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Severe Weather Hazard
Severe storms are a recurring hazard in Yountville, 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 town’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 Yountville, 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 Yountville’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. Yountville 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 Town’s continued vulnerability to cascading hazards, including flooding and slope instability along the slough system.

While severe storms in Yountville 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 town’s most at-risk residents.

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 CAL OES SUBMITTAL - JUNE 2026
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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 Town of Yountville 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. Yountville’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, severe weather, drought, and wildfire.

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 town 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 town. Prolonged dry conditions may also impact local creeks and riparian systems, which play an important role in stormwater conveyance, habitat, and groundwater recharge.

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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 Town of Yountville. While much of the town is urbanized, it is bordered by wildland and open space areas that are susceptible to wildfire. Fires in surrounding areas can affect the town through evacuation impacts, degraded air quality, and strain on emergency services.

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 town, 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 Yountville. 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.

5.5.3 Climate Change Impacts & Vulnerable Populations
Climate change is expected to exacerbate many of the natural hazards affecting the Town of Yountville, 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 Yountville 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 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, CAL OES SUBMITTAL - JUNE 2026
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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.

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.

5.5.4 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 5-14. 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 5-16 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 5-14 and Table 5-16 Table 5-14: Town of Yountville Hazard Problem Statements Problem No. Hazard Area of
Concern
Primary
Agency
Problem Description Related MA
ps-CC-YT-12 Climate
Change
Victim Town of
Yountville
Yountville’s large and growing senior
population is increasingly vulnerable to
climate-driven hazards such as extreme heat,
smoke from wildfire, and severe weather,
elevating risks of illness and energy insecurity
among medically and economically
vulnerable residents.
ma-CC-NCo-16,
ma-CC-YT-122,
ma-AH-YT-224
ps-CC-YT-335 Climate
Change
Threat Town of
Yountville
Climate change is projected to increase the
frequency and severity of hazards such as
extreme heat, drought, wildfire, severe
weather, and flood.
ma-HH-YT-227
ps-DF-YT-29 Dam Failure Victim Town of
Yountville
Approximately 1,600 residents, including those
in two mobile home parks, are located in dam
inundation zones associated with Veterans
Home Dam (Lake Hinman) or Conn Creek
Dam.
ma-FL-NCo-55,
ma-FL-NCo-56,
ma-FL-YT-72,
ma-DF-NCo-120,
ma-AH-YT-224,
ma-DF-YT-226
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Problem No. Hazard Area of
Concern
Primary
Agency
Problem Description Related MA
ps-DF-YT-30 Dam Failure Threat Town of
Yountville
Multiple critical facilities and key access
routes are located in dam inundation zones
associated with Veterans Home Dam (Lake
Hinman) and Conn Creek Dam.
ma-FL-NCo-55,
ma-FL-NCo-56,
ma-FL-YT-72,
ma-DF-NCo-120,
ma-DF-YT-226
ps-DR-YT-43 Drought Impact Town of
Yountville
The increasing frequency and duration of
multi-year droughts strain Yountville’s water
supply reliability, reducing available water for
emergency and basic household needs.
ma-DR-YT-31
ps-DR-YT-336 Drought Victim Town of
Yountville
The impacts of drought disproportionately
affect seniors, low-income households, and
residents in multifamily or rental housing
with limited control over water use.
ma-DR-YT-31
ps-DR-YT-337 Drought Threat Town of
Yountville
The frequency, severity, and duration of
droughts are increasing due to climate
change.
ma-DR-YT-31
ps-EQ-YT-72 Earthquake Victim Town of
Yountville
More than 3,200 residents are exposed to very
strong to severe shaking from a major
earthquake, with renters, low-income
residents, and those living in older or mobile
homes facing disproportionate risk.
ma-AH-NCo-4,
ma-EQ-YT-45
ps-EQ-YT-73 Earthquake Threat Town of
Yountville
Over $1 billion in property and all critical
facilities are located in strong to severe
shaking zones, creating a high potential for
long-duration outages, functional losses, and
costly post-event repairs.
ma-EQ-YT-45
ps-EQ-YT-338 Earthquake Threat Town of
Yountville
Local soil conditions, proximity to fault lines,
aging utility systems, and buildings that lack
adequate seismic retrofits increase the threat
of structural collapse, utility disruption, and
hazardous material releases during a major
earthquake.
ma-EQ-YT-45
ps-EQ-YT-339 Earthquake Impact Town of
Yountville
A major earthquake could damage or destroy
critical facilities and disrupt community
lifelines, including for water, power, and
transportation.
ma-EQ-YT-45
ps-FL-YT-114 Flood Victim Town of
Yountville
Flooding along Hopper Creek, Beard Ditch, and
other drainageways places more than 1,300
residents and millions of dollars in property
value at risk during heavy rainfall and
atmospheric river events.
ma-FL-NCo-55,
ma-FL-NCo-56,
ma-FL-YT-75,
ma-FL-YT-76
ps-FL-YT-116 Flood Victim Town of
Yountville
Yountville has one repetitive loss property
located on 2 Talent Lane with two losses and
total paid claims of $23,457.66.
ma-FL-YT-73
ps-FL-YT-340 Flood Threat Town of
Yountville
The frequency and severity of flooding is
expected to increase due to climate change.
ma-FL-YT-73
ps-HH-YT-346 High Heat Victim Town of
Yountville
Extreme heat events place seniors, medically
vulnerable residents, outdoor workers, and
low-income households at elevated risk of
heat-related illness.
ma-AH-YT-224,
ma-HH-YT-227
ps-HH-YT-347 High Heat Threat Town of
Yountville
The number of extreme heat days and warm
nights and duration of heat waves is
anticipated to increase with climate change.
ma-AH-YT-224,
ma-HH-YT-227
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Problem No. Hazard Area of
Concern
Primary
Agency
Problem Description Related MA
ps-FL-YT-115 Severe Weather Victim Town of
Yountville
Heavy rain events such as atmospheric rivers
cause localized flooding along the natural
creeks and drainages that traverse the area.
ma-FL-YT-74
ps-SW-YT-341 Severe Weather Impact Town of
Yountville
Increasingly intense wind events topple trees,
damage power lines, and obstruct roadways,
causing power outages, blocked emergency
routes, and service disruptions.
ma-FL-YT-72,
ma-SW-YT-225
ps-SW-YT-342 Severe Weather Impact Town of
Yountville
Winter storms can disrupt transportation and
power services from high wind, heavy rain,
and ice.
ma-FL-YT-72,
ma-SW-YT-225
ps-SW-YT-343 Severe Weather Victim Town of
Yountville
Seniors, medically dependent residents, and
those without backup power or transportation
are particularly vulnerable to prolonged
outages and isolation from severe weather
events.
ma-FL-YT-72,
ma-SW-YT-225
ps-WF-YT-176 Wildfire Victim Town of
Yountville
Vulnerable residents, including seniors and
those with underlying medical conditions,
may face evacuation challenges during fastmoving fires and are disproportionately at risk from smoke impacts.
ma-WF-NCo-90,
ma-WF-YT-109
ps-WF-YT-344 Wildfire Threat Town of
Yountville
Neighborhoods along Yountville’s western
edge, including areas near the Veterans Home
and adjacent WUI, lie in moderate to very high
fire hazard severity zones with limited ingress
and egress.
ma-AH-YT-224
ps-WF-YT-345 Wildfire Impact Town of
Yountville
Regional wildfires and prescribed burns
degrade air quality in Yountville, causing days
to weeks of unhealthy conditions and
disrupting outdoor businesses and tourism.
ma-WF-YT-109,
ma-AH-YT-224
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5.6 Mitigation Strategy
This section provides the framework for how the Town of Yountville 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 town’s prioritized mitigation actions.

Together, these elements demonstrate how Yountville 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 Yountville, the strategy outlined in this annex reflects the outcomes of the countywide planning process while also addressing the town’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 town, county, and regional planning mechanisms. Each action identifies responsible parties, potential funding sources, and the resources needed for implementation.

For Yountville, this strategy provides a framework for strengthening resilience by combining Town-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, Yountville 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 5.6.1, Capabilities and Opportunities, provides a summary of the city’s capacity to address natural hazards.
▪ Section 5.6.2, Mitigation Action Plan, presents Yountville’s prioritized actions to guide implementation in coordination with countywide strategies. ▪ Section 5.6.3, 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 Yountville’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 Yountville’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.

5.6.1 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 municipality, the Town of Yountville manages growth within the framework of California’s comprehensive planning, zoning, subdivision, and environmental regulations. Much of the Town’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. Yountville is bordered by the Napa River to the east and hillside terrain to the west, which constrains outward expansion and concentrates future development in areas already subject to natural hazards.

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

Hazard vulnerability is addressed through coordination with the Town’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 Town’s eligibility for disaster recovery and resilience funding.

Climate change is expected to intensify several of the hazards affecting Yountville, including 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 Yountville therefore emphasizes sustainable building practices, water conservation, protection of natural floodplain functions, and climateadaptive 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 Yountville. The Town’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 Yountville has largely occurred within an established urban footprint, 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 hazard-aware site design, infrastructure resilience, and emergency access.

Long-range planning efforts also account for future climate conditions, recognizing that 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
Yountville’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 (National Institute of Building Sciences, 2019). 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. Yountville enforces these standards locally, providing a strong foundation for resilient construction.

The Town 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, Yountville 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, Yountville 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, Yountville 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 Yountville 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 town 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 Yountville’s remaining vacant and developable land has already undergone environmental review through Program Environmental Impact Reports (PEIRs) prepared as part of adopted specific plans. These PEIRs 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 town continues to use LOS analysis as a nonCEQA 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 Yountville.

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

Development & Hazard Considerations
Development in the Town of Yountville occurs within a physical and regulatory context shaped by natural hazards, environmental constraints, and long-term growth management policies. As a general law town operating under California planning and environmental regulations, Yountville 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 Town’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 Town 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 Town’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 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 Town 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 Town of Yountville’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 Yountville 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 the Town of Yountville summarizes the various types of capabilities it has for hazard mitigation currently. The assessment also identifies opportunities to integrate, expand, and improve the city’s capabilities for future hazard mitigation. Table 5-15 provides a CAL OES SUBMITTAL - JUNE 2026
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comprehensive list of capabilities and identifies the current status, current mitigation use, and future opportunities.

Planning & Regulatory
The Town of Yountville has strong planning and regulatory capabilities that support hazard risk reduction and resilient development. The Town 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 Town’s General Plan, with updated hazard, climate change, and environmental justice policies being incorporated through the General Plan update. Capital investments are prioritized through the Capital Improvements Program (CIP), which supports resilient infrastructure for water, storm drainage, transportation, and public services.

Yountville maintains several hazard reduction programs, including stormwater management and erosion control, water conservation, and public outreach through the Town’s emergency preparedness webpage.

The town also promotes non-structural earthquake preparedness and household-level mitigation actions.

The Town 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 Town 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 5-16). Key opportunities for future hazard mitigation integration with the Town of Yountville’s existing planning mechanisms include incorporating the updated risk assessment, hazard-specific vulnerability findings, and projected climate change impacts into the Enhanced Emergency Shelter Network (ma-AH-YT-224), Severe Weather Notification System (ma-FL-YT-72), and Wildfire Mitigation Outreach & Education action (ma-WF-YT-109).

Administrative & Technical
The Town of Yountville 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 Town 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 CAL OES SUBMITTAL - JUNE 2026
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Town Manager serves as the Floodplain Administrator and Director of Emergency Services, ensuring direct coordination between planning, emergency management, and floodplain compliance. Fire prevention and wildfire mitigation functions are supported by the Napa County/CALFIRE Department through the Fire Marshal.

While the Town 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 Town of Yountville has strong warning and emergency communication capabilities to alert residents, businesses, and visitors of hazardous conditions and emergency situations. The Town 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.

Emergency information is also communicated through Town 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.

Fiscal
The Town of Yountville 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 town plans and programs.

The Town 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 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.

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Yountville 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 Town 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 town 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 Town of Yountville has strong education and outreach capabilities that support public awareness, preparedness, and risk reduction for natural hazards. The Town 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 Town actively uses social media platforms, including town websites, Facebook, Instagram, Nextdoor, 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.

Yountville 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 Town also collaborates with the Napa County Resource Conservation District, which provides outreach related to wildfire, drought, and other environmental hazards.

Town 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 5-15: Town of Yountville 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
2022 California Building Standards Code (Title 24)
via Municipal Code Title 15, including CBC, CEBC,
CalGreen, and administrative provisions
BCEGS Rating 0 0 0
Public Protection (ISO Class) 0 0 0
Hazard-Related Development
Standards
Green Green Green
Hazard-related development standards
implemented through Titles 15, 16, and 17, including
Zoning and Subdivision Design/Development
Standards, Water Efficient Landscaping, and
Floodplain Management Regulations
Zoning Ordinance
Green Green Green Zoning Ordinance administered by Planning & Building under Municipal Code Title 17
Hazard-Specific Ordinance
Green Green Green
Hazard-specific ordinances include Fire
Regulations, Floodplain Management, Tree
Preservation, Water Conservation, and Stormwater
Regulations
Growth Management Ordinance Green Green Green 2019 General Plan, including Land Use Element Hazard Reduction Programs
(Annually Conducted)
Capital Improvements Program
(CIP) or Plan Green Green Green
CIP covers seven project areas, including Drainage
& Flood Control, Streets and Transportation, and
Water Distribution
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HMP Integration
Resource Status
Current
Mitigation
Use
Future
Opportunity Notes / Additional Detail
Erosion/Sediment Control
Program
Green Green Green
Municipal Code Title 13 establishes stormwater
management and erosion/runoff controls and
standards; Town participates in the countywide
stormwater program (NCSPPP) for construction
BMPs and compliance
Hazard-Related Public Outreach
Program Green Green Green Emergency Preparedness webpage, social media, resources, and alerts enrollment
Urban Water Management Plan
Green Green Green
Water Conservation Plan and Napa Valley Drought
Contingency Plan; groundwater planning
coordinated with County’s Napa Valley Subbasin
GSP
Stormwater Management
Program (Annual Inspections) Green Green Green
Implements stormwater management program and
coordinates with NCSPPP for inspections,
compliance, and public education
Seismic Safety Program (Nonstructural) Green Green Green 2019 General Plan Safety & Hazards Elements and Earthquake Preparedness webpage
Earthquake Modernization Plan
(Building Safety)
Yellow Yellow Green
No standalone earthquake modernization program;
building safety managed through California
Building Code adoption and enforcement
Hazard Plans
General Plan Safety Element
Green Green Green
General Plan Safety & Hazards Element covers
seismic, geologic, flood, fire, and climate change
hazards (amended in 2024 under Resolution No. 24-
4309)
Site Plan Review Requirements
Green Green Green Title 17 establishes site design review and permitting procedures
General Plan Environmental
Justice Element Green Green Green No standalone element, but General Plan Land Use Element contains an EJ section
Community Wildfire Protection
Plan (CWPP) Green Green Green Follows 2021 Napa County Community Wildfire Protection Plan
Economic Development Plan
Green Green Green 2019 General Plan History, Community and Economic Sustainability Element
Floodplain Management Plan
Green Green Green 2019 General Plan Safety & Hazards Element and Title 15 Floodplain Management Regulations
Stormwater Management Plan
Green Green Green Town participates in Napa Countywide Stormwater Pollution Prevention Program; CIP drainage projects
Emergency Operations Plan
Green Green Green 2024 Napa County EOP and Town of Yountville Annex
Climate Action Plan Green Green Green 2016 Climate Action Plan Climate Vulnerability
Assessment Yellow Yellow Green
No town-specific assessment, but regional climate
vulnerability assessed through countywide
RCAAP/CAC process
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HMP Integration
Resource Status
Current
Mitigation
Use
Future
Opportunity Notes / Additional Detail
Urban Greening Plan
Green Green Green General Plan Open Space & Conservation Element Ground Water Management
Planning / Plans
Green Green Green
Groundwater planning coordinated with County’s
Napa Valley Subbasin GSP; Town runs recycledwater and water-conservation programs National Flood Protection
Program (NFIP)
Floodplain Management
Regulations Green Green Green Title 15 Floodplain Management Regulations Flood Insurance Education and
Technical Assist. Green Green Green Floodplain Management webpage and technical assistance from Public Works Dept staff
Flood Insurance Study Green Green Green 2016 FEMA FIS 06055CV000C Elevation Certificates Green Green Green Maintained by Public Works Dept Flood Hazard Mapping / ReMapping Green Green Green FEMA FIRMs effective 2008 and 2016 Community Rating System (CRS)
Orange Orange Yellow Not currently participating; future opportunity but limited by staff capacity
Administrative and
Technical
Community Planning and
Development Services
Community Planner Green Green Green Dedicated staff in Planning and Building Dept Planner/Engineer (Land
Development) Green Green Green Dedicated staff in Planning and Building and Public Works Depts
Engineer/Professional
(Construction)
Green Green Green Dedicated staff in Public Works Dept
Planner/Engineer/Scientist
(Natural Hazards) Green Green Green Shared among staff in Public Works Dept Transportation Planner Green Green Green Shared among staff in Public Works Dept Resiliency Planner Yellow Yellow Green No dedicated staff; shared among Planning and Building Dept staff
Building Code Official (Full time
or Augmented) Green Green Green Building Official in Planning and Building Dept Floodplain Administrator Green Green Green Director of Public Works Dept Fire Marshal
Green Green Green By contract with Napa County Fire Dept/CAL FIRE Dedicated Public Outreach
Personnel Green Green Green
Shared among staff in Town Manager's Office and
Town Clerk and Communications, Planning and
Building, and Public Works Depts
GIS Specialist and Capability
Green Green Green Dedicated staff in Administration Dept; supported by Napa County GIS
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HMP Integration
Resource Status
Current
Mitigation
Use
Future
Opportunity Notes / Additional Detail
Emergency Manager Yellow Yellow Green No dedicated staff; supported by Napa County OES Dedicated Grant Manager, Writer,
or Specialist Green Green Green Shared among staff in Administration, Finance, Public Works, and Planning and Building Depts
Other N/A N/A N/A
Warning Systems/Services
General
Green Green Green ALERT Napa County, Nixle, local radio, social media and Hi-Lo sirens
Flood
Green Green Green ALERT Napa County, Nixle, local radio, social media and Hi-Lo sirens
Tornado
Green Green Green ALERT Napa County, Nixle, local radio, social media and Hi-Lo sirens
Wildfire
Green Green Green ALERT Napa County, Nixle, local radio, social media and Hi-Lo sirens
Geological Hazards
Green Green Green ALERT Napa County, Nixle, local radio, social media and Hi-Lo sirens
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 utility service and impact fees
Benefit assessments Orange Orange Yellow Not currently used; 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 Collected as system impact fees for water, drainage, floodplain control, etc.

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
Green Green Green Collected as drainage impact and grading permit fees
Capital Improvement Project
Funding Green Green Green CIP funds support infrastructure upgrades and community resilience
Education / Outreach
Capabilities
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HMP Integration
Resource Status
Current
Mitigation
Use
Future
Opportunity Notes / Additional Detail
Education/Outreach
Resources
Website Dedicated to Hazard
Topics Green Green Green Emergency Preparedness webpage through Town Manager's Office
Dedicated Social Media
Green Green Green
Facebook, YouTube, and other social media used for
emergency preparedness and hazard tips;
Yountville Ready initiatives
Local Citizen Groups That
Communicate Hazard Risks Yellow Yellow Green Napa Communities Firewise Foundation, Fire Safe Councils
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; Yountville Ready
initiative with regular cookouts with public safety
partners
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 Green Green Green Bi-weekly newsletter with preparedness topics Community Emergency
Response Team (CERT) Green Green Green Napa County CERT Fire Safe Councils
Green Green Green Active Fire Safe Councils in surrounding area; Napa Community Firewise Foundation
Firewise Yellow Yellow Green Not currently designated, but supported by Napa Communities Firewise Foundation
StormReady Orange Orange Green Not currently 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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5.6.2 Town of Yountville Mitigation Action Plan
Yountville’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 town
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 Yountville’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 Yountville is documented in Table 5-16, 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 5-18) that links the strategy to its associated hazard and supports consistent monitoring and reporting.

Yountville’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 town’s boundaries and require collaboration with county, regional, and state partners. By aligning local actions with regional Figure 5-18: Mitigation Action Number Key
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strategies, Yountville 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.

Collectively, these mitigation actions provide a roadmap for reducing hazard risk, protecting vulnerable populations, and strengthening the long-term resilience of Yountville.

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Table 5-16: Town of Yountville 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-YT-224 All Hazard PE&A - Public
Education &
Awareness ,
ES -
Emergency
Services
2026 Town of
Yountville
Enhanced
Emergency
Shelter
Network
In collaboration with Napa County and other
partners, identify new emergency shelter
options and upgrade existing shelters with
backup power, ADA accommodations, improved
HVAC systems, and other enhancements to
address a variety of hazard scenarios and
community needs. Also develop a transportation
assistance program that identifies and supports
vulnerable populations with limited mobility in
accessing the shelter network.

Planning &
Building
Department
High Medium 5-10 Years Project HMGP / BRIC ,

CDBG DRI ,
General Fund
High ps-CC-YT-12, ps-DF-YT-29, psEH-YT-346, ps-EH-YT-347, psWF-YT-344, ps-WF-YT-345 ma-DF-YT-226 Dam
Failure
PE&A - Public
Education &
Awareness ,
ES -
Emergency
Services
2020 Town of
Yountville
Dam
Inundation
Awareness &
Response
Update public awareness signage, emergency
notification, and evacuation route planning, and
improve community education efforts for areas
downstream of Veterans Home and Conn Creek
Dams.

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

HMGP / BRIC ,
General Fund
Low ps-DF-YT-30, ps-DF-YT-29
ma-DR-YT-31 Drought PE&A - Public
Education &
Awareness
2020 Town of
Yountville
Drought
Resilience
Support
Program
Develop and implement a drought education
and support program with targeted outreach to
seniors and low-income households and
incentives for home water-efficiency
improvements.

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

HMGP / BRIC ,
General Fund
High ps-DR-YT-43, ps-DR-YT-336,
ps-DR-YT-337
ma-EQ-YT-45 Earthquake PE&A - Public
Education &
Awareness
2020 Town of
Yountville
Earthquake
Outreach &
Education
Enhance earthquake outreach efforts with focus
on renters and low-income households,
insurance, and available retrofit resources
through annual events, website updates, social
media posts, and printed media.

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

HMGP / BRIC ,
General Fund
Medium ps-EQ-YT-72, ps-EQ-YT-73,
ps-EQ-YT-74, ps-EQ-YT-338,
ps-EQ-YT-339
ma-EH-YT-227 Extreme
Heat
NRP - Natural
Resource
Protection , SP
- Structural
Projects
2026 Town of
Yountville
Community
Cooling
Measures
Develop and implement community cooling
measures, including urban forest expansion,
installing shade structures along pedestrian
corridors and in public spaces, and removal and
replacement of dark, heat-absorbing urban
surfaces.

Public Works
Department
High High 3-5 Years Project HMGP / BRIC ,
General Fund
Medium ps-EH-YT-346, ps-EH-YT-347,
ps-CC-YT-335
ma-FL-YT-73 Flood NRP - Natural
Resource
Protection , SP
- Structural
Projects
2020 Town of
Yountville
Floodplain
Restoration &
Drainage
Improvements
Identify key areas with reoccurring flooding,
especially during heavy rain events, and
implement drainage upgrades and floodplain
restoration projects to improve conveyance
capacity and stormwater system resilience,
including through nature-based solutions that
improve habitat and water quality.

Public Works
Department
High High 3-5 Years Project HMGP / BRIC ,
FMA , General
Fund
High ps-FL-YT-116, ps-FL-YT-340
ma-SW-YT-72 Severe
Weather
PRV -
Prevention ,
PE&A - Public
Education &
Awareness ,
ES -
Emergency
Services , SP -
Structural
Projects
2020 Town of
Yountville
Severe
Weather
Notification
System
Enhance the existing notification system for
severe weather events, including heavy rain and
flooding, high wind, and winter storms, to
achieve real-time threat recognition through
warning system upgrades (e.g., stream gauges)
and improved prediction integration with NWS
and County alerting.

Town Manager's
Office
Medium Medium 1-3 Years Project HMGP / BRIC ,
General Fund
Medium ps-DF-YT-29, ps-DF-YT-30,
ps-SW-YT-341, ps-SW-YT-342,
ps-SW-YT-343
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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-SW-YT-225 Severe
Weather
High Wind PPRO -
Property
Protection ,
NRP - Natural
Resource
Protection , ES
- Emergency
Services , SP -
Structural
Projects
2026 Town of
Yountville
High Wind
Facility &
Corridor
Hardening
Develop a program to regularly conduct tree risk
assessments and mitigation along major access
routes and around critical facilities. Install
backup power for critical facilities.

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

HMGP / BRIC ,
General Fund
Medium ps-SW-YT-343, ps-SW-YT-342,
ps-SW-YT-341
ma-WF-YT-109 Wildfire PE&A - Public
Education &
Awareness ,
NRP - Natural
Resource
Protection
2020 Town of
Yountville
Wildfire
Mitigation
Outreach &
Education
Work with Napa Firewise to develop a wildfire
mitigation education program that
communicates requirements around and
encourages access improvements, adequate
addressing and water supply, vegetation
management, and structure hardening.

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

HMGP / BRIC ,
General Fund ,
CalFIRE
High ps-WF-YT-176, ps-WF-YT-177,
ps-WF-YT-345
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5.6.3 Status of Previous Mitigation Actions
In 2020, the Town of Yountville 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 5-17 provides status updates for all of the previous mitigation actions in the Town of Yountville HMP, from which many of the mitigation actions in Table 5-16 were sourced and revised.

Table 5-17: Town of Yountville Status of Previous Mitigation Actions Mitigation
No.

Hazard
Type
Status Year Primary
Agency
Title/Description Reason Cancelled/
Completed
ma-DF-YT226Dam
Failure
Ongoing 2020 Town of
Yountville
Dam Inundation Awareness &
Response
Revised
ma-DR-YT31Drought Ongoing 2020 Town of
Yountville
Drought Resilience Support
Program
Revised
ma-EQ-YT45Earthquake Ongoing 2020 Town of
Yountville
Earthquake Outreach &
Education
Revised
ma-FL-YT73Flood Ongoing 2020 Town of
Yountville
Floodplain Restoration &
Drainage Improvements
Revised
ma-FL-YT72Flood Ongoing 2020 Town of
Yountville
Severe Weather Notification
System
Revised
ma-WF-YT109Wildfire Ongoing 2020 Town of
Yountville
Wildfire Mitigation Outreach &
Education
Revised
ma-CC-YT122Climate
Change
Cancelled 2020 Town of
Yountville
Develop a public education
campaign to spread
awareness on the increasing
effects of climate change and
everyday actions citizens can
take to conserve water and
minimize their carbon
footprint
YV-01-2020 & YV-203-
2020 combined and
revised
ma-FL-YT74Flood Cancelled 2020 Town of
Yountville
Secure grant funding for a
river restoration program to
reduce flood damage, enhance
environmental quality, and
maintain fish habitat.

YV-03-2020 & YV-04-
2020 combined and
revised
ma-FL-YT75Flood Cancelled 2020 Town of
Yountville
Invest in flood prediction
modeling to support Napa
County's floodplain
management, hazard
identification, risk
assessment, and climate
adaptation efforts.

YV-02-2020, YV-07-
2020 & YV-08-2020
combined and revised
ma-FL-YT76Flood Cancelled 2020 Town of
Yountville
Enhance the existing flood
notification program to
achieve real-time flood threat
recognition capability.

YV-02-2020, YV-07-
2020 & YV-08-2020
combined and revised
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Section 6. American Canyon Fire Protection
District
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Napa County
2026 Multi-Jurisdictional Hazard Mitigation Plan Update American Canyon Fire Protection District (ACFPD)
Special District Annex
Section 6. American Canyon Fire Protection District........................................................6-7

6.1 Scope & Purpose .....................................................................................................................................................................6-7

6.2 Jurisdictional Setting...........................................................................................................................................................6-7

6.2.1 Geography & Climate ..................................................................................................................................................6-8

6.2.2 Demographics & Vulnerable Populations..........................................................................................................6-11

6.2.3 Economy........................................................................................................................................................................6-24

6.2.4 Growth Trends & Future Development..............................................................................................................6-24

6.3 Planning Process .................................................................................................................................................................6-25

6.3.1 Public Input & Draft Review ...................................................................................................................................6-28

6.4 What’s New.............................................................................................................................................................................6-28

6.4.1 Mitigation Activities .................................................................................................................................................6-28

6.4.2 Mitigation Successes................................................................................................................................................6-29

6.5 Risk Assessment..................................................................................................................................................................6-32

6.5.1 Hazard Screening & Prioritization ......................................................................................................................6-32

6.5.2 Vulnerability to Specific Hazards........................................................................................................................6-36

6.5.3 Climate Change Impacts & Vulnerable Populations....................................................................................6-47

6.5.4 Hazard Problem Statements................................................................................................................................. 6-48

6.6 Mitigation Strategy .............................................................................................................................................................6-50

6.6.1 Capabilities & Opportunities.................................................................................................................................. 6-51

6.6.2 American Canyon Fire Protection District Mitigation Action Plan ......................................................6-61 CAL OES SUBMITTAL - JUNE 2026
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List of Figures
Figure 6-1: ACFPD Geographic Overview Map......................................................................................................................6-10 Figure 6-2: ACFPD Median Household Income Map..........................................................................................................6-13 Figure 6-3: ACFPD Poverty Status Map ...................................................................................................................................6-14 Figure 6-4: ACFPD Housing Occupancy Map........................................................................................................................6-15 Figure 6-5: ACFPD Dependent Age Groups Map..................................................................................................................6-17 Figure 6-6: ACFPD Disabled Elderly Map................................................................................................................................6-18 Figure 6-7: ACFPD Race and Ethnicity Map......................................................................................................................... 6-20 Figure 6-8: ACFPD Spanish-Speaking Households Map ..................................................................................................6-21 Figure 6-9: ACFPD CDC Social Vulnerability Index Map................................................................................................. 6-23 Figure 6-10: ACFPD Targeted Sheep Grazing ....................................................................................................................... 6-30 Figure 6-11: Extrication Tools Purchased from Grant........................................................................................................6-31 Figure 6-12: ACFPD Risk Assessment Matrix....................................................................................................................... 6-34 Figure 6-13: Exposure Summary – ACFPD Wildfire Risk................................................................................................ 6-38 Figure 6-14: Exposure Summary – ACFPD Earthquake Risk (M7.1 Hunting Creek–Berryessa)...................... 6-40 Figure 6-15: Exposure Summary – ACFPD Earthquake Risk (M6.7 West Napa)......................................................6-41 Figure 6-16: Exposure Summary – ACFPD Sea Level Rise ............................................................................................. 6-46 Figure 6-17: Mitigation Action Number Key ..........................................................................................................................6-61 List of Tables
Table 6-1: ACFPD Planning Team and Steering Group Members .................................................................................6-25 Table 6-2: ACFPD Planning Team Meetings......................................................................................................................... 6-27 Table 6-3: ACFPD Document Review of Potential Hazards .............................................................................................6-33 Table 6-4: ACFPD Hazards Prioritization Summary...........................................................................................................6-35 Table 6-5: ACFPD Hazard Problem Statements................................................................................................................... 6-48 Table 6-6: ACFPD Capabilities and Opportunities Assessment.....................................................................................6-57 Table 6-7: ACFPD Mitigation Action Plan.............................................................................................................................. 6-63 CAL OES SUBMITTAL - JUNE 2026
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Adoption Resolution
To comply with the Federal Disaster Mitigation Act of 2000 (DMA 2000), the American Canyon Fire Protection District Board of Directors 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 district’s commitment to reducing the impacts of natural hazards within its jurisdiction and across Napa County.

A copy of the district’s adoption record is provided on the following pages. Adoption records for all jurisdictions are summarized in Volume 1, Table ES-1.

ADOPTION RECORD TO BE INSERTED UPON COMPLETION.

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Section 6. American Canyon Fire Protection District

6.1 Scope & Purpose
This Jurisdictional Annex for the American Canyon Fire Protection District (ACFPD) of the 2026 Napa County Multi-Jurisdictional Hazard Mitigation Plan (MJHMP) details the hazard mitigation planning elements specific to the district’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 district. This annex provides additional information specific to the district, with a focus on hazard identification and risk assessment, vulnerability assessment, problem statements, mitigation strategy, and capabilities assessment. Below are ACFPD’s Points of Contact:

Primary Point of Contact Alternate Point of Contact
Geoff Belyea, Fire Chief
American Canyon Fire Protection District
911 Donaldson Way, E American
Canyon, CA 94503
Telephone: (707) 551-0650
email: [email protected]
Cliff Campbell, Asst Fire Chief
American Canyon Fire Protection District
911 Donaldson Way, E American
Canyon, CA 94503
Telephone: (707) 551-0650
email: [email protected]

6.2 Jurisdictional Setting
The ACFPD is an independent special district located in southern Napa County, California, providing fire protection, emergency medical services, fire prevention, and related emergency response services to the City of American Canyon and select unincorporated areas of southern Napa County. The district serves an area of approximately 7 square miles, encompassing a mix of residential neighborhoods, commercial and industrial development, transportation corridors, open space, wetlands, and wildland–urban interface (WUI) areas.

American Canyon is situated at the southern end of the Napa Valley, near the northeastern edge of the San Pablo Bay. The district’s jurisdiction is bounded generally by the Napa River and adjacent wetland preserve to the west, the foothills of the Sulphur Springs Mountain Range to the east, the City of Vallejo to the south, and the Napa County Airport and agricultural lands to the north. This geographic setting creates a diverse hazard environment, including flood-prone lowlands, seismically active areas, transportation and industrial risk corridors, and wildfire-susceptible hillside terrain.

The district’s location at a regional transportation crossroads, near State Route 29 and other arterial routes, supports significant industrial and logistics uses, including wine processing, storage, bottling, and distribution facilities.

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ACFPD was originally established in 1955 and formally recognized by the State of California in 1957.

Following the incorporation of the City of American Canyon in 1992, the district continued to operate as a subsidiary special district serving the city and surrounding areas.

The district is governed by a five-member elected Board of Directors, which serves as the policymaking body and provides financial oversight and strategic direction. Day-to-day operations are managed by the Fire Chief, who serves as the Chief Executive Officer of the District and is responsible for administration, emergency response, personnel, and coordination with partner agencies.

Fire protection and emergency medical services for the City of American Canyon are provided through ACFPD, while the City retains responsibility for land use planning, development approvals, public works, utilities, and other municipal services. The district coordinates closely with city departments on development review, fire prevention, emergency access, and infrastructure planning, particularly as new residential, commercial, and industrial projects are constructed within District boundaries.

In addition to city areas, ACFPD also provides service to portions of unincorporated southern Napa County under established service arrangements. The district works in coordination with Napa County, neighboring fire agencies, and regional mutual aid partners to support large-scale emergency response, disaster operations, and specialized incidents.

American Canyon has experienced steady population growth and development over the past decade, with continued residential expansion, commercial investment, and industrial intensification anticipated in coming years. New housing subdivisions, hotels, and industrial facilities contribute to increased service demand for emergency response, fire prevention inspections, and disaster preparedness.

To support growth-related impacts, ACFPD relies on a combination of property tax revenue, fire service and assessment fees, development impact fees, and other funding mechanisms to maintain current service levels and plan for future capital needs.

ACFPD’s location within Napa County and the State of California are shown in Figure 6-1. ▪ Year of Incorporation: 1957
▪ Service area: ~7 square miles
▪ Approximate Population Served: 21,801 (includes City of American Canyon)

6.2.1 Geography & Climate
ACFPD is located in southern Napa County, California, at the southern gateway to the Napa Valley and along the northeastern edge of the San Pablo Bay. The district’s service area includes the entirety of the City of American Canyon as well as select unincorporated areas of southern Napa County. Its geographic position places the district at the intersection of coastal, valley, and foothill environments, resulting in a diverse range of physical conditions and hazard exposures.

The western portion of the district is defined by low-lying terrain adjacent to the Napa River and extensive wetland preserve areas connected to the San Pablo Bay. These areas are particularly susceptible to riverine flooding, tidal influences, and the compounding effects of sea level rise during major storm events. Much of CAL OES SUBMITTAL - JUNE 2026
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the central and western developed area lies on relatively flat valley floor terrain, supporting residential neighborhoods, commercial centers, industrial facilities, and major transportation corridors.

Moving eastward, the district transitions into rolling hills and the lower foothills of the Sulphur Springs Mountain Range. These upland areas contain grasslands, open space, and residential development that interface directly with wildland vegetation, creating wildland–urban interface conditions. The topographic variation in these areas contributes to increased wildfire exposure, access and evacuation challenges, and localized slope instability. In addition, the district’s proximity to regional transportation routes and its role as a hub for wine processing, storage, and distribution introduce elevated structural fire risk, hazardous materials exposure, and transportation-related incident potential within the jurisdiction.

American Canyon experiences a Mediterranean climate characterized by cool, wet winters and warm, dry summers. The majority of annual precipitation occurs between November and March, when Pacific storm systems can bring prolonged or intense rainfall averaging ~18 inches. Summers are generally dry, with extended periods of low humidity and elevated temperatures. This seasonal precipitation pattern contributes to both winter flood risk and summer drought and wildfire conditions.

Average daily temperatures are moderated by the district’s proximity to San Pablo Bay, though inland heat can develop during summer months, particularly in eastern portions of the city farther from marine influence. Average summer temperatures range from the high 70s to mid-90s°F (25–35°C), while winter temperatures typically range from the mid-40s to low 60s°F (7–16°C). Climate change projections for the region indicate continued warming trends, increased variability in precipitation, more intense storm events, longer dry periods, and rising sea levels.

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Figure 6-1: ACFPD Geographic Overview Map
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6.2.2 Demographics & Vulnerable Populations
ACFPD serves a diverse and growing population centered within the City of American Canyon, which is the second-largest city in Napa County. Population growth within the district has increased demand for emergency response, fire prevention services, and disaster preparedness, particularly in newly developed residential areas and higher-density housing.

American Canyon’s population is characterized by substantial racial, ethnic, and cultural diversity. The community includes a large proportion of Hispanic and Latino residents, along with significant Asian populations. Many households include multigenerational families, and languages other than English are commonly spoken at home. These demographic characteristics underscore the importance of culturally appropriate emergency communication, multilingual outreach, and inclusive hazard mitigation strategies to ensure all residents receive timely and actionable information before, during, and after emergencies.

The district also serves several populations that may be disproportionately vulnerable to the impacts of natural hazards. These include older adults, individuals with disabilities, persons with access or functional needs, and lower-income households. Older adults may be more susceptible to heat-related illness, medical complications during power outages, and mobility limitations during evacuations. Individuals with disabilities or access and functional needs may require additional assistance, specialized equipment, or advance planning to safely respond to emergencies such as wildfires, flooding, or earthquakes.

Lower-income households and renters may face increased challenges related to hazard mitigation and recovery, including limited access to insurance, fewer resources for home retrofits, and reduced ability to absorb the financial impacts of disasters. In addition, residents employed in service, industrial, and agricultural support sectors may face heightened exposure to hazards due to workplace conditions, transportation dependencies, or limited schedule flexibility during emergency events.

American Canyon also contains several land uses and facilities that support vulnerable populations, including schools, childcare facilities, senior housing, healthcare-related services, and community facilities. These sites require special consideration in emergency planning due to occupant characteristics, evacuation needs, and continuity-of-operations requirements. Disruptions to utilities, transportation, or emergency access can have disproportionate consequences for these populations during hazard events.

Income & Housing
Household income and housing conditions within ACFPD vary spatially across the district and play an important role in shaping vulnerability to natural hazards and the capacity for preparedness, response, and recovery. Analysis of American Community Survey (ACS) data illustrates distinct geographic patterns in both median household income and poverty rates within the district, reflecting differences in housing stock, development history, and land use.

As shown in Figure 6-2, median household income across much of the district is relatively high, particularly in central and northern residential areas and newer developments. These areas generally exhibit household CAL OES SUBMITTAL - JUNE 2026
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incomes at or above regional averages, which can support greater access to insurance, home retrofitting, emergency supplies, and post-disaster recovery resources. Higher-income neighborhoods may also have newer housing stock that benefits from more recent building codes and hazard-resistant construction standards.

In contrast shown in Figure 6-3, lower median household incomes are more prevalent in portions of the southern and eastern areas of the district, as well as near older residential neighborhoods and higherdensity housing areas. These same areas correspond with higher concentrations of households experiencing poverty, as shown in the poverty status map. These areas may be more sensitive to service disruptions and recovery delays following hazard events due to limited financial resources.

Housing characteristics further influence vulnerability within the district. Areas with higher poverty rates are more likely to contain older homes, rental properties, and multifamily housing, which may be less likely to have been retrofitted for seismic safety, flood protection, or wildfire resilience. Renters may have limited authority or resources to invest in structural mitigation measures and may face greater displacement risk following a disaster. Additionally, households with limited financial resources may experience challenges evacuating, securing temporary housing, or returning to normal conditions after an emergency.

Housing occupancy patterns within the American Canyon Fire Protection District vary geographically and provide important insight into community vulnerability and resilience. As shown in Figure 6-4, many central and northern neighborhoods exhibit high rates of owner-occupied housing, indicating greater housing stability and a higher likelihood of long-term investment in property maintenance and hazard mitigation measures. In contrast, portions of the southern and eastern areas of the district show lower percentages of owner-occupied units and correspondingly higher concentrations of renter-occupied housing. These areas may face increased vulnerability during hazard events, as renters often have limited ability to implement structural mitigation improvements and may be at greater risk of displacement following disasters. Higher renter concentrations can also complicate emergency communication, evacuation coordination, and post-disaster recovery, particularly when coupled with lower household incomes or higher poverty rates.

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Figure 6-2: ACFPD Median Household Income Map
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Figure 6-3: ACFPD Poverty Status Map
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Figure 6-4: ACFPD Housing Occupancy Map
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Dependent & Disabled Populations
The distribution of dependent and disabled populations within ACFPD varies across the district and is an important factor in understanding community vulnerability to natural hazards. Analysis of American Community Survey (ACS) data shows distinct geographic patterns in the concentration of residents in dependent age groups, children and older adults, as well as elderly residents living with disabilities. These populations may require additional assistance before, during, and after emergency events, and their spatial distribution has direct implications for evacuation planning, emergency response, and recovery.

As shown in Figure 6-5, dependent age groups, including residents under 18 and adults over 65, are more concentrated in northern and eastern residential neighborhoods of the district. Areas with higher proportions of dependent populations often include family-oriented neighborhoods, multifamily housing, and established residential areas. During hazard events, children and older adults may face increased challenges related to evacuation, mobility, access to transportation, and reliance on caregivers or institutional support systems such as schools, childcare facilities, and senior services. Disruptions to these systems during emergencies can significantly increase stress on households and responders alike.

The ACS data and Figure 6-6 also indicate that certain areas of the district have elevated percentages of elderly residents aged 65 and older who are living with disabilities. These populations may be particularly vulnerable during disasters due to limited mobility, reliance on medical equipment, increased sensitivity to extreme temperatures, and the need for ongoing healthcare or in-home support services. Power outages, road closures, and delays in emergency access can pose serious risks to disabled elderly residents, even during relatively short-duration hazard events.

The overlap between higher concentrations of dependent populations and disabled elderly residents and other vulnerability factors, such as lower household incomes, higher renter occupancy, or proximity to hazard-prone areas, can compound risk within specific neighborhoods.

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Figure 6-5: ACFPD Dependent Age Groups Map
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Figure 6-6: ACFPD Disabled Elderly Map
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Race, Ethnicity & Language
Racial, ethnic, and linguistic characteristics within ACFPD vary across the district and are important considerations for understanding social vulnerability and effective emergency communication. ACS data shows clear geographic patterns in racial and ethnic predominance, as well as the prevalence of nonEnglish languages spoken at home, reflecting the district’s cultural diversity and settlement history.

The ACS race and ethnicity snapshot map, Figure 6-7, indicates that much of the district includes a mix of racial and ethnic groups, with Hispanic or Latino populations predominating in several central and southern residential areas. Other portions of the district show higher concentrations of residents identifying as White alone, not Hispanic or Latino, as well as areas with notable Asian populations, particularly in parts of the northern and northeastern areas. This spatial diversity highlights the presence of multiple cultural communities within the district, each of which may have different levels of access to resources, varying degrees of trust in public institutions, and distinct preferences in communication.

Language spoken at home further illustrates patterns relevant to emergency preparedness and response.

Figure 6-8 shows that a substantial share of the population in many parts of the district speaks Spanish at home, with the highest concentrations occurring in central and southern neighborhoods. In these areas, a significant percentage of residents may have limited English proficiency, which can present barriers to receiving, understanding, and acting on emergency warnings, evacuation orders, and recovery information if communications are not provided in accessible and culturally appropriate formats.

The overlap between areas with higher proportions of Hispanic or Latino residents and higher rates of Spanish language use underscores the importance of multilingual emergency communication and outreach. During fast-moving hazard events such as wildfires or floods, delays or misunderstandings related to language barriers can increase risk to life and property. In addition, households where English is not the primary language may face challenges navigating disaster assistance programs, insurance processes, or recovery resources following an emergency.

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Figure 6-7: ACFPD Race and Ethnicity Map
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Figure 6-8: ACFPD Spanish-Speaking Households Map
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Social Vulnerability Index (SVI)
The Centers for Disease Control and Prevention (CDC) Social Vulnerability Index (SVI) for ACFPD 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 6-9 shows lower SVI scores, indicating lower overall social vulnerability, are generally observed in eastern and southwestern portions of the district characterized by newer residential development, higher household incomes, and greater rates of owner-occupied housing. These areas typically have more resources available to prepare for hazards, respond to emergency warnings, and recover following disaster events. Residents in lower-vulnerability areas may also have greater access to transportation, insurance coverage, and social networks that support evacuation and post-disaster stability.

In contrast, moderate to higher SVI scores are concentrated in several central and southern portions of the district. These areas align with neighborhoods that also exhibit higher poverty rates, greater renter occupancy, higher proportions of dependent age groups, and increased prevalence of non-English language use. The convergence of these factors can increase sensitivity to hazard impacts and create barriers to timely evacuation, access to emergency information, and participation in recovery programs. Even when physical exposure to hazards is similar, socially vulnerable populations often experience disproportionate impacts due to limited resources and support systems.

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Figure 6-9: ACFPD CDC Social Vulnerability Index Map
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6.2.3 Economy
The economy of ACFPD is closely tied to the broader economic structure of the City of American Canyon and southern Napa County, reflecting a mix of residential, commercial, industrial, and service-oriented land uses. The district serves a community that functions both as a local employment center and as a commuter population connected to regional job markets in Napa Valley, Vallejo, and the greater Bay Area.

Economic activity within the district includes light industrial and warehouse uses, logistics and distribution facilities, retail centers, hospitality services, and local professional and public-sector employment.

Commercial and industrial areas located along major transportation corridors support employment opportunities while also introducing specific hazard considerations related to hazardous materials, transportation incidents, and continuity of operations during emergencies. These employment centers contribute to the district’s daytime population and influence emergency response demand during business hours.

Residential development plays a significant role in the local economy, with many residents commuting outside the district for work in Napa, Solano County, and the greater Bay Area. Household income levels vary across the district, creating differences in economic resilience and recovery capacity following disasters. While higher-income households may be better positioned to absorb short-term disruptions, lower-income workers, particularly those employed in service, retail, or hourly wage sectors, may face greater economic hardship from business closures, evacuations, or infrastructure damage.

Public-sector institutions, schools, utilities, and healthcare-related services also represent important economic anchors within the district. Continuity of these services during hazard events is critical not only for life safety but also for maintaining economic stability and supporting post-disaster recovery. Disruptions to transportation networks, power, water, or communications systems could have cascading economic impacts affecting both residents and employers.

6.2.4 Growth Trends & Future Development
ACFPD has experienced steady population and development growth over the past decade, a trend that is expected to continue into the foreseeable future. American Canyon’s strategic location at the southern end of Napa Valley, close to major transportation corridors such as State Route 29 and Interstate 80, has made it an attractive area for residential expansion, commercial investment, and industrial development. This growth reflects broader regional patterns, as households and employers seek more affordable land and proximity to both Napa and the Bay Area job markets.

Residential growth within the district has been driven largely by new subdivisions and infill development, particularly in the central and southern portions of the service area. These neighborhoods include a mix of single-family homes and multifamily housing, contributing to a diversifying housing stock and an increasing population base. Continued residential development is supported by local planning policies and market demand, and it is expected to expand further as remaining vacant parcels are developed. This CAL OES SUBMITTAL - JUNE 2026
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ongoing growth elevates demand for emergency services, fire prevention activities, infrastructure maintenance, and hazard mitigation planning.

Commercial and industrial development has also increased in recent years, with logistics, warehousing, light manufacturing, and service-oriented businesses locating near major roadways. The presence of these economic sectors contributes to local employment opportunities and broadens the district’s economic base.

However, industrial growth also brings new emergency management considerations, including hazardous materials handling, increased traffic volumes, and the need for specialized response capabilities.

Future development within the district is likely to focus on several key areas. First, continued residential infill and the build-out of remaining residentially zoned parcels will expand population density in established neighborhoods. Second, commercial revitalization along primary corridors aims to support local services, retail, and business growth that serve both residents and commuters. Third, industrial and logistics land uses are expected to continue playing a role in the local economy, especially given American Canyon’s proximity to regional freight networks.

6.3 Planning Process
ACFPD followed the planning process detailed in Volume 1, Section 2, including participating in the countywide Hazard Mitigation Planning Team (HMPT) and formulating their own internal planning team to support the broader planning process.

The district’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 district, this included postings to the district website and social media, and outreach events, as documented in Appendix B. Examples of Key Stakeholders engaged by Napa County on behalf of the district with relevance to the development of ACFPD’s mitigation strategy include the USDA and other federal agencies; CAL FIRE and other state agencies; other jurisdictions; community-based organizations such as local Chamber of Commerce chapters; 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 district’s annex, as described in Volume 1 Table 2-9. The district’s internal planning team participants, their positions, and how they participated in the planning process are shown in Table 6-1.

Table 6-1: ACFPD Planning Team and Steering Group Members Team Members Title Description of Involvement
Geoff Belyea Fire Chief Lead Point-of-Contact, HMPT Kickoff, HMPT #1 thru #4, BO #1 and #2
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ACFPD staff 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 6-2 that engaged the district’s planning team, which included key district 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.

On December 10, 2025, participants engaged in a hexagon mapping activity designed to visually identify mitigation actions that could benefit from or require 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.

Throughout the series of breakout meetings, the district 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 14, 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 June 22, 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.

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

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Table 6-2: ACFPD 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
ACFPD Planning Team
Breakout Meeting #1
August 14, 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
jurisdiction-specific
priority hazards
▪ Identify capabilities
and potential
mitigation actions
▪ Community
engagement
volunteers
County-Wide HMPT Meeting #3
March 25, 2025
ACFPD Planning Team
Breakout Meeting #2
June 22, 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
jurisdiction-specific
capabilities
▪ Consensus on
jurisdiction-specific
areas of concern
▪ Consensus on priority
mitigation actions and
collaboration
opportunities
▪ Community
engagement
volunteers
County-Wide HMPT Meeting #4
December 10, 2025
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6.3.1 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 agencies. These comments were incorporated into the district’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.

6.4 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. This is the first time ACFPD has participated in the MJHMP process.

While not included in the 2020 plan, the district has since strengthened its focus on resilience through key efforts. Through this MJHMP process, ACFPD has identified its highest-priority hazards, developed hazardspecific problem statements, and proposed actionable mitigation strategies.

By aligning with countywide partners and leveraging regional resources, ACFPD has strengthened its capacity to prepare for, withstand, and recover from disasters while continuing to protect its unique coastal community character.

6.4.1 Mitigation Activities
Mitigation activities within ACFPD focus on reducing the long-term risk to life, property, and critical infrastructure from natural and human-caused hazards. These activities are implemented through a combination of fire prevention programs, land use coordination, infrastructure improvements, public education, and operational planning, and are aligned with local, county, state, and federal hazard mitigation objectives. ACFPD’s mitigation approach emphasizes proactive risk reduction, integration with development decisions, and equitable protection of vulnerable populations.

A central component of the district’s mitigation strategy is fire prevention and code enforcement. ACFPD enforces applicable California Fire Code and local amendments to ensure new development and existing buildings incorporate fire-resistive construction, adequate access, water supply, and defensible space where required. Plan review and inspection activities help reduce structural fire risk, support wildfire resilience at the wildland–urban interface and ensure that commercial and industrial facilities manage hazardous materials appropriately.

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Vegetation management and wildfire risk reduction are also key mitigation priorities. ACFPD supports defensible space requirements, fuel reduction practices, and coordination with property owners and partner agencies to reduce wildfire intensity and improve firefighter access. These efforts are particularly important along the eastern hillsides and transitional areas between developed neighborhoods and open space.

Ongoing vegetation management helps mitigate wildfire spread, protects evacuation routes, and reduces exposure to smoke and ember intrusion during wildfire events.

Flood risk reduction and stormwater management activities contribute to mitigation by addressing hazards associated with the Napa River, tidal influences from San Pablo Bay, and localized drainage systems. While primary responsibility for flood control infrastructure lies with other agencies, ACFPD coordinates with the City of American Canyon and Napa County to ensure emergency access, response planning, and public awareness in flood-prone areas. Protection of critical facilities, roadways, and utilities from flooding is essential to maintaining emergency response capabilities during major storm events.

Public education and outreach are integral to ACFPD’s mitigation efforts. The district participates in community risk reduction programs that promote household preparedness, evacuation planning, smoke alarm installation, and fire-safe behaviors. Outreach efforts are increasingly tailored to reach renters, nonEnglish-speaking households, seniors, and other vulnerable populations identified through demographic and Social Vulnerability Index analysis. Effective communication before disasters improves compliance with evacuation orders and reduces injuries and losses during emergencies.

Operational planning and interagency coordination further support mitigation goals by strengthening response readiness and continuity of operations. ACFPD collaborates with the City of American Canyon, Napa County, law enforcement, public works, utilities, and neighboring fire agencies to plan for large-scale emergencies. Joint training, mutual aid agreements, and participation in countywide planning initiatives help reduce response time, improve situational awareness, and limit cascading impacts during hazard events.

6.4.2 Mitigation Successes
Vegetation Management
In September 2023, ACFPD, in partnership with Napa County Fire, the City of American Canyon, and the Napa Communities Firewise Foundation, implemented a sheep grazing program as a natural vegetation management strategy. The program utilizes sheep from a local producer to reduce dry grasses and other flammable vegetation in targeted areas, supporting wildfire risk reduction while aligning with the city’s sustainability and environmental stewardship goals.

Sheep grazing provides an effective alternative to conventional vegetation management methods that rely on chemical herbicides or heavy machinery. The approach improves soil health through natural fertilization, enhances biodiversity, and allows for quiet, non-disruptive treatment of areas that may be difficult to access with equipment. By reducing fuel loads, the program helps create a more fire-resistant CAL OES SUBMITTAL - JUNE 2026
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landscape and improves visibility in parks, vacant lots, and public spaces, contributing to both wildfire mitigation and community safety.

The grazing program also represents a cost-effective and environmentally responsible mitigation measure.

By lowering long-term vegetation management costs, the city is able to allocate resources more efficiently while advancing public safety, climate resilience, and ecological health. This initiative demonstrates American Canyon’s commitment to innovative, sustainable hazard mitigation practices that reduce wildfire risk and support overall community resilience.

In addition, ACFPD, in partnership with Napa Firewise, the City of American Canyon, Napa County, and Napa Pasture Protein, is implementing targeted sheep grazing to reduce wildfire risk in high-hazard areas throughout American Canyon (Figure 6-10). The program focuses on creating defensible space and fuel breaks in community buffer zones and open space preserves, including challenging terrain such as the Newell Open Space Preserve where traditional vegetation management methods are difficult to implement.

Grazing provides a low-impact, environmentally sustainable alternative to mechanical clearing or herbicide use, supporting biodiversity, native landscapes, and soil health while reducing fine fuels. When combined with individual property defensible space efforts, these grazing activities help protect entire neighborhoods.

To date, hundreds of acres across American Canyon have been treated through this approach, contributing to long-term wildfire mitigation and community resilience.

Figure 6-10: ACFPD Targeted Sheep Grazing
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Grant Funding
ACFPD has demonstrated strong fiscal responsibility and operational leadership by securing grant funding to enhance emergency response capabilities while minimizing financial impacts on the community.

Through multiple competitive grants, the district obtained approximately $177,000 to purchase critical equipment, including a shallow-bottom rescue boat for water rescue operations along the Napa River, nine sets of structural firefighting personal protective equipment, and two complete sets of battery-operated extrication tools (“Jaws of Life”). These investments improve firefighter safety, strengthen rescue capabilities, and increase operational efficiency across a range of emergency scenarios.

In addition to equipment upgrades, the district has made significant progress in workforce development and organizational capacity. Targeted training and staff development initiatives resulted in multiple internal promotions, including four firefighters promoted to Fire Captain and two Fire Captains advanced to Battalion Chief. The district also enhanced staffing levels through successful firefighter/paramedic recruitment, hiring three new personnel to strengthen emergency medical response. Continued integration of new technologies has further improved communication systems, data-driven decision-making, and overall emergency response effectiveness. Collectively, these accomplishments support the district’s mission, improve community safety, and enhance long-term resilience.

ACFPD also received a grant
from the California Fire
Foundation to support ongoing
wildfire prevention and
preparedness efforts in response
to increasingly year-round
wildfire risk. The grant funding
was used to purchase wildland
personal protective equipment
(PPE), enhancing firefighter
safety during wildfire response
operations. The California Fire
Foundation provides statewide
grant support to fire departments
and community organizations for wildfire education, planning, equipment, fuels reduction, and community safety initiatives. This investment strengthens the district’s ability to safely and effectively respond to wildfires while supporting broader community resilience and preparedness efforts in American Canyon.

Figure 6-11: Extrication Tools Purchased from Grant
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6.5 Risk Assessment
This section focuses on profiling hazards specific to ACFPD 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 district, and information on district-specific differences in hazard vulnerability across the planning area. It also identifies total district assets at risk, including people, property, and critical facilities and infrastructure within the district. 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.

6.5.1 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.

ACFPD’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 district. Table 6-3 provides a crosswalk of hazards identified in select planning documents, including the 2020 Napa County MJHMP, 2022 ACFPD Long Range Master Plan, 2022 Climate Change Adaptation 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 ACFPD and which ones were not.

The internal planning group then ranked hazards based on their probability of affecting ACFPD and potential impacts on the community. Figure 6-12 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 district’s vulnerability to specifically identified hazards.

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Table 6-3: ACFPD Document Review of Potential Hazards
Hazard 2020 Napa County
MJHMP
2022 ACFPD Long Range
Master 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 6-12: ACFPD 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 district’s Planning Team, before further refinement, are identified in the county’s completed matrix in Figure 6-12. Table 6-4 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 6-4: ACFPD Hazards Prioritization Summary
Hazard Priority Explanation
Earthquake / Liquefaction Extreme Profiled in Volume 1, Section 3.3.4, and Section 6.5.2.2 in this annex (not including Liquefaction due to low probability and impact potential) Wildfire Medium Profiled in Volume 1, Section 3.3.1, and Section 6.5.2.1 in this annex Flood -
Profiled in Volume 1, Section 3.3.2; not a priority due to low probability and impact potential
Levee Failure -
Profiled in Volume 1, Section 3.3.2; not a priority due to low probability and impact potential
Extreme Weather / Storms High
Profiled in Volume 1, Section 3.3.5, and Section 6.5.2.3 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 -
Profiled in Volume 1, Section 3.3.6; not a priority due to being outside jurisdictional mission and authority
Geologic / Mass Movement -
Profiled in Volume 1, Section 3.3.5; not a priority due to low probability and impact potential
Extreme Heat -
Profiled in Volume 1, Section 3.3.8; not a priority due to being outside jurisdictional mission and authority
Agricultural Pests -
Profiled in Volume 1, Section 3.3.9; not a priority due to being outside jurisdictional mission and authority
Sea Level Rise -
Profiled in Volume 1, Section 3.3.9; not a priority due to low probability and impact potential
Climate Change Medium Profiled in Volume 1, Section 3.3.9, and Section 6.5.2.4 in this annex and discussed as a compounding hazard in relevant profiles
Dam Failure -
Profiled in Volume 1, Section 3.3.3; not a priority due to being outside jurisdictional mission and authority
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6.5.2 Vulnerability to Specific Hazards
Assessing vulnerabilities exposes the unique characteristics of individual hazards and begins the process of narrowing down which areas within the district 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 district’s planning group estimated vulnerable populations, properties, and assets, and potential losses. In addition, the exposure of district assets to drought, earthquake, wildfire, flood, and climate change hazards were also considered.

Many of the hazard profiles include a snapshot map and damage estimation tables that illustrate the district’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 four hazards for the ACFPD, some of which encompass sub hazards such as Liquefaction and Heavy Rain.

Wildfire
SECTION 6.5.2.1
Earthquake
SECTION 6.5.2.2
Severe Weather
SECTION 6.5.2.3
Climate Change
SECTION 6.5.2.4
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Wildfire Hazard
Wildfire represents a persistent and evolving hazard for the ACFPD, shaped by the district’s location at the interface between urban development, open space preserves, and regional wildland areas. Although much of American Canyon consists of developed residential and commercial land uses, the surrounding hillsides, grasslands, and natural areas create conditions where wildfire ignition and spread remain credible risks.

Seasonal drought, elevated temperatures, wind events, and increasingly variable precipitation patterns further contribute to wildfire potential, consistent with broader trends observed throughout California (CAL FIRE; California Climate Assessment).

Figure 6-13 illustrates that moderate to high wildfire hazard areas are primarily concentrated along the district’s eastern and northeastern boundaries, where developed neighborhoods transition into open space and upland terrain. These areas are characterized by natural vegetation, steeper slopes, and fuel continuity that can support fire growth under conducive weather conditions. Open space preserves, including areas with documented fire history, present unique mitigation challenges due to terrain, access limitations, and ecological considerations. While these landscapes provide important environmental and recreational benefits, they also represent potential wildfire pathways affecting adjacent residential communities.

Importantly, the exposure summary associated with the snapshot indicates that no population, parcels, or critical infrastructure assets are currently mapped within the highest wildfire risk zones. This reflects the fact that the most severe hazard classifications are generally located outside the district’s primary developed footprint. However, this condition does not eliminate wildfire risk. Fires originating outside jurisdictional boundaries, or within moderate and high hazard areas, may still threaten structures, evacuation routes, utility systems, and air quality. Ember intrusion, smoke impacts, and rapid fire spread driven by wind conditions can affect developed areas even when ignition occurs remotely.

Wildfire risk within the ACFPD is influenced not only by hazard location but also by development patterns and vegetation characteristics. Residential neighborhoods located near open space areas may experience heightened exposure due to proximity to unmanaged fuels, ornamental vegetation, and potential evacuation constraints. Transportation corridors and utility infrastructure can also be vulnerable to wildfire-related disruptions, creating cascading impacts affecting emergency response and community function.

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Figure 6-13: Exposure Summary – ACFPD Wildfire Risk
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Earthquake Hazard
Earthquakes represent a significant natural hazard for the ACFPD, consistent with the district’s location within the seismically active San Francisco Bay Area and proximity to several major fault systems. Regional seismic sources, including the West Napa Fault, Rodgers Creek Fault, Hayward Fault, and broader North Bay fault network, present credible earthquake scenarios capable of generating strong to severe ground shaking within the district. Historical seismic events, most notably the 2014 South Napa Earthquake, underscore the region’s ongoing exposure to earthquake risk.

The earthquake scenario maps illustrate the range of potential shaking intensities affecting the district under different seismic events. In Figure 6-14, The Hunting Creek – Berryessa Earthquake Scenario (M7.1) indicates limited exposure within the district, with only a small number of residents and parcels modeled within severe shaking intensity zones. This reflects the relative distance of the scenario epicenter from the district and the attenuation of shaking effects across the region.

In contrast, the West Napa Earthquake Scenario (M6.7), Figure 6-15 demonstrates substantially greater consequences for the ACFPD. Under this scenario, the entire district is subject to strong to very strong shaking intensities (Modified Mercalli Intensity VII–VIII). Exposure analysis indicates that approximately 21,800 residents, representing essentially 100 percent of the district’s population, would experience significant ground shaking. Similarly, all mapped parcels and the full assessed structural value, exceeding $7.4 billion in improvement value, fall within the modeled shaking impact area. Two critical infrastructure facilities are also identified within the affected zone.

Strong earthquake shaking presents a wide range of hazards and secondary impacts. Structural damage to residential, commercial, and industrial buildings may occur, particularly in older structures or facilities not designed to modern seismic standards. Nonstructural hazards, including falling debris, utility disruptions, hazardous materials releases, and roadway damage, can significantly affect life safety and emergency response operations. Transportation networks may experience reduced capacity due to bridge damage, surface failures, or debris blockage, complicating emergency access and evacuation.

In addition to direct shaking impacts, earthquakes may generate cascading hazards relevant to ACFPD operations. These include fire following earthquake, water system failures, communications disruptions, and increased demand for rescue and medical response. Soft soils and alluvial deposits present in portions of the district may amplify shaking effects or contribute to localized ground failure, including settlement or lateral spreading.

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Figure 6-14: Exposure Summary – ACFPD Earthquake Risk (M7.1 Hunting Creek–Berryessa) CAL OES SUBMITTAL - JUNE 2026
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Figure 6-15: Exposure Summary – ACFPD Earthquake Risk (M6.7 West Napa) CAL OES SUBMITTAL - JUNE 2026
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Severe Weather Hazard
Severe weather hazards affecting the ACFPD primarily include heavy rainfall events and strong winds from severe storm systems. While the region very rarely experiences hazards such as tornadoes or blizzards, localized severe weather conditions can produce significant public safety, infrastructure, and emergency response impacts.

Heavy Rainfall & Storm Events
Although drought conditions are common, California increasingly experiences episodic, high-intensity rainfall events. Atmospheric river systems can deliver large volumes of precipitation over short durations, contributing to urban flooding, roadway impacts, and localized drainage failures.

Within ACFPD, heavy rainfall events may lead to localized street and low-lying area flooding, stormwater system overload, Increased vehicle collisions, debris flows and erosion, impacts to access routes and emergency response times. Heavy precipitation following wildfire events can further elevate risk by destabilizing soils and increasing runoff rates.

Thunderstorms, while less frequent than in other regions, may produce lightning, brief heavy rainfall, and localized wind impacts. Lightning poses both ignition risk and potential impacts to power systems. Severe storm systems may also generate hazardous driving conditions and localized infrastructure disruptions.

High Wind
Strong winds are a critical severe weather factor due to their relationship with wildfire ignition and spread.

Wind-driven fire behavior significantly increases suppression difficulty, rate of spread, and ember cast distances (CAL FIRE). Even outside wildfire contexts, high wind events may result in downed trees and powerlines, traffic hazards, structural damage, and increased power outage likelihood. Wind events combined with dry conditions represent a particularly high-risk scenario for the district.

Severe weather hazards within the ACFPD frequently generate secondary and cascading impacts rather than isolated catastrophic events. Extreme heat, heavy rainfall, and strong wind conditions can collectively contribute to increased demand for emergency medical services and rescue operations, particularly during periods of prolonged heat exposure or hazardous travel conditions. Severe weather may also disrupt transportation networks through localized flooding, debris, reduced visibility, or roadway obstructions, which can in turn affect evacuation, emergency response times, and daily mobility.

In addition, severe weather events are commonly associated with power outages resulting from infrastructure strain, wind damage, or PSPS measures. These outages can produce broader operational and community consequences, including interruptions to critical facilities, communication challenges, and increased reliance on emergency services. Weather-related stress on infrastructure systems, including power, drainage, and transportation assets, may further compound risks during extreme events.

Importantly, certain severe weather conditions, particularly high temperatures, low humidity, and strong winds, can significantly elevate wildfire potential, intensifying both ignition risk and fire behavior.

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Public health impacts also represent a key cascading concern, as severe weather conditions may exacerbate heat-related illness, respiratory issues, injury risk, and other medical emergencies. Climate projections indicate that variability and intensity of weather patterns are expected to increase across California, amplifying both temperature extremes and episodic high-intensity precipitation events. These trends suggest that severe weather hazards may increasingly influence emergency response demands, infrastructure performance, and overall community resilience within the district.

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 1901–1960 average to that of 1986–2016. 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).

Climate change is expected to influence both the frequency and severity of natural hazards affecting the ACFPD. As part of the San Francisco Bay Area, the district is subject to climate-driven shifts in temperature, precipitation patterns, drought cycles, and extreme weather variability. These changes are not considered stand-alone hazards but rather risk multipliers that can intensify existing threats and alter hazard behavior over time.

Climate projections for California indicate continued increases in average temperatures, more frequent and prolonged heat events, reduced snowpack statewide, greater precipitation variability, and an increased likelihood of both severe drought and episodic high-intensity rainfall events. Rising temperatures directly contribute to elevated wildfire risk by drying vegetation, extending fire seasons, and increasing fuel aridity.

Even in areas not traditionally considered wildfire-prone, hotter and drier conditions may heighten ignition potential and fire intensity.

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Hydrologic impacts associated with climate change may also affect flood behavior. While overall precipitation totals may fluctuate, storms are projected to become more concentrated and intense, increasing the probability of short-duration, high-impact rainfall events. These conditions can overwhelm drainage systems, increase localized flooding, accelerate erosion, and elevate slope instability. At the same time, longer dry periods between storms may further degrade soil stability and vegetation cover, compounding runoff and landslide susceptibility when heavy rainfall does occur.

Drought conditions are similarly expected to intensify under future climate scenarios. Extended dry periods can stress vegetation, reduce water availability, increase tree mortality, and elevate wildfire fuel loads.

Drought may also place strain on regional water supply systems, indirectly affecting fire suppression capacity and emergency response operations.

Extreme heat represents another key climate-sensitive concern. Increasing temperatures may drive higher rates of heat-related illness, particularly among vulnerable populations, while also placing additional demand on emergency medical services. Heat can further impact infrastructure systems, including power reliability, transportation surfaces, and mechanical equipment performance.

Importantly, climate change introduces greater uncertainty into hazard planning. Historical patterns may become less reliable predictors of future conditions, requiring adaptive mitigation strategies, flexible emergency planning, and continued monitoring of emerging risk trends. For ACFPD, climate change underscores the need to integrate long-term resilience considerations into wildfire mitigation, flood management, emergency response planning, infrastructure protection, and community preparedness efforts.

Sea Level Rise
Sea level rise represents a long-term, climate-driven hazard with important implications for the ACFPD. Due to the district’s proximity to the Napa River, San Pablo Bay, and tidally influenced wetlands, rising sea levels have the potential to influence flood behavior, groundwater conditions, infrastructure performance, and emergency response operations over time. Unlike acute hazards, sea level rise is a gradual process that primarily functions as a hazard multiplier by exacerbating existing flood-related risks.

Exposure analysis derived from NOAA sea level rise modeling provides important context for understanding the scale of potential impacts within the district. Figure 6-16 indicates that approximately 96 residents and 4 parcels are located within areas potentially affected by projected sea level rise scenarios.

The associated improvement value exposure totals approximately $3.87 million, with a total parcel value exposure of approximately $3.01 million. While these values represent a relatively small percentage of the district’s overall population and development footprint, they highlight that localized exposure exists, particularly in low-lying areas adjacent to tidally influenced waterways and shoreline zones.

Projected increases in sea levels within the San Francisco Bay Area are expected to contribute to more frequent nuisance flooding, expanded floodplain boundaries, and increased backwater effects. Even modest increases in baseline water levels can significantly increase the extent and depth of flooding during storm CAL OES SUBMITTAL - JUNE 2026
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events, particularly when combined with king tides and heavy precipitation. As a result, areas currently experiencing limited or infrequent flooding may face increased flood recurrence over time.

Sea level rise may also contribute to secondary physical effects, including shoreline erosion, wetland migration, and rising groundwater tables. Elevated groundwater conditions can increase the potential for localized flooding, soil saturation, and infrastructure impacts, even outside traditionally mapped flood hazard areas. These processes can gradually alter site conditions, affecting roads, utilities, and structural foundations.

From an operational perspective, sea level rise presents several planning considerations for ACFPD.

Increased flood frequency and duration may influence emergency access routes, evacuation patterns, and infrastructure reliability. Repetitive or chronic flooding may also affect building performance and long-term community resilience. Although current exposure levels appear limited, future development patterns, changing flood dynamics, and evolving climate conditions may alter risk profiles over time.

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Figure 6-16: Exposure Summary – ACFPD Sea Level Rise
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6.5.3 Climate Change Impacts & Vulnerable Populations
Climate change introduces risk factors that do not affect all community members equally. Within the ACFPD, shifts in temperature, precipitation patterns, and hazard frequency have implications that are closely tied to social, economic, and demographic conditions. Understanding how climate-related hazards intersect with vulnerable populations is essential for effective mitigation, preparedness, and emergency response planning.

Projected climate conditions for California indicate increasing average temperatures, more frequent and intense heat events, greater variability in precipitation, and heightened potential for both drought and extreme storm events. These changes influence multiple hazards already present within ACFPD, including wildfire, flooding, severe weather, and public health emergencies. While the physical hazards may affect broad geographic areas, the severity of impacts often varies based on population characteristics.

Extreme heat represents one of the most significant climate-related threats to vulnerable populations. Older adults, individuals with disabilities, young children, and those with underlying health conditions are particularly sensitive to heat stress. Heat-related illness risks increase for populations with limited access to air conditioning, medically dependent individuals, and those experiencing economic constraints. Lowerincome households may face barriers related to cooling costs, housing quality, or access to safe refuge during prolonged heat events. These conditions can translate into increased EMS demand and elevated life safety risks.

Climate change also influences wildfire conditions through rising temperatures, extended dry seasons, and altered vegetation patterns. Vulnerable populations may face disproportionate impacts during wildfire events due to evacuation challenges, mobility limitations, or reduced access to transportation. Individuals with disabilities, elderly residents, and households without reliable vehicles may require additional assistance during rapid-onset incidents. Smoke exposure further compounds health risks, particularly for populations with respiratory conditions, children, and older adults.

Flooding and severe storm events introduce a different set of vulnerabilities. Residents in lower-lying areas, multifamily housing, or older structures may experience higher exposure to flood-related damages. Renters and lower-income households often have limited financial capacity to recover from property damage or temporary displacement. Language barriers may also influence access to warnings, preparedness information, and recovery resources, particularly during fast-moving events requiring immediate protective action.

Economic vulnerability plays a critical role in climate resilience. Households with limited financial resources may face challenges preparing for hazards, maintaining insurance coverage, or absorbing postdisaster losses. Recovery timelines frequently vary based on income, employment stability, and housing tenure. These disparities are well-documented in disaster research and are expected to become more pronounced as climate-related hazards intensify.

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Dependent populations, including children and elderly residents, introduce additional planning considerations. Schools, care facilities, and medically dependent individuals may require specialized emergency procedures during extreme weather, smoke events, or power outages. Disruptions to utilities or transportation systems can disproportionately affect individuals reliant on medical equipment, public transit, or caregiver networks.

Language and communication factors further shape vulnerability. Households with limited English proficiency may encounter barriers accessing warnings, evacuation instructions, and hazard preparedness guidance. Effective risk communication increasingly requires multilingual outreach, culturally appropriate messaging, and diversified alerting strategies.

Importantly, vulnerability is not solely defined by demographic categories but by the interaction between hazard exposure, sensitivity, and adaptive capacity. Many residents may fall into multiple vulnerability dimensions simultaneously, such as elderly individuals living alone, lower-income households with dependent children, or individuals with disabilities residing in hazard-prone areas.

6.5.4 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 6-5. 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 6-7 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 6-5 and Table 6-7 Table 6-5: ACFPD Hazard Problem Statements
Problem No. Hazard Area of
Concern
Primary
Agency
Problem Description Related MA
ps-EQ-ACFPD001Earthquake Impact American
Canyon Fire
Protection
District
The district lies within shaking zones for West
Napa Fault events (M6.7 scenario), which
could damage older structures, disrupt
communications, and reduce operational
readiness.
ma-AH-ACFPD001, ma-EQACFPD-002
ps-EQ-ACFPD002Earthquake Threat American
Canyon Fire
Protection
District
Station 211's undersized and outdated design
makes it vulnerable to seismic damage,
impacting continuity of operations.

Deficiencies in apparatus bay size and lack of
modern construction features.
ma-EQ-ACFPD001
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Problem No. Hazard Area of
Concern
Primary
Agency
Problem Description Related MA
ps-EQ-ACFPD003Earthquake Impact American
Canyon Fire
Protection
District
Earthquake damage to transportation
networks (Highway 29 corridor, James Rd
area) could slow emergency response and
limit mutual-aid access.
ma-AH-ACFPD001, ma-EQACFPD-002
ps-EQ-ACFPD004Earthquake Victim American
Canyon Fire
Protection
District
Limited administrative staffing and absence of
Battalion Chief coverage on every shift reduce
the district's ability to manage incident
command complexity during a major seismic
event.
ma-AH-ACFPD001, ma-AHACFPD-002
ps-EW-ACFPD001Extreme
Weather
Impact American
Canyon Fire
Protection
District
Severe wind events have caused operational
disruptions, toppled trees, and damaged utility
lines in American Canyon, posing risks to
emergency response routes and delaying
resource deployment. Frequent weatherrelated service interruptions. ma-SW-ACFPD002, ma-SWACFPD-001
ps-EW-ACFPD002Extreme
Weather
Impact American
Canyon Fire
Protection
District
Heavy rainfall and atmospheric river events
can overwhelm stormwater systems in the
city, limiting apparatus mobility and
increasing response times.
ma-SW-ACFPD002, ma-SWACFPD-001
ps-EW-ACFPD003Extreme
Weather
Victim American
Canyon Fire
Protection
District
ACFPD lacks a fully developed severe-weather
response protocol, increasing vulnerability
during high-impact storms and wind events.
ma-SW-ACFPD001, ma-AHACFPD-002
ps-WF-ACFPD001Wildfire Threat American
Canyon Fire
Protection
District
Eucalyptus stands along Commerce Blvd
create elevated fire hazard potential and
ember-cast risk near residential subdivisions
and critical facilities, including adult care
homes.
ma-WF-ACFPD001, ma-WFACFPD-002, maWF-ACFPD-003
ps-WF-ACFPD002Wildfire Victim American
Canyon Fire
Protection
District
Adult and childcare facilities located near
vegetated greenbelts are at increased risk due
to limited mobility of residents and staffing
constraints for evacuation.
ma-WF-ACFPD001, ma-WFACFPD-002, maWF-ACFPD-003
ps-WF-ACFPD003Wildfire Impact American
Canyon Fire
Protection
District
Prevailing winds can carry smoke and embers
into populated areas, impacting air quality and
triggering medical aid demand spikes, which
align with ACFPD's heavy EMS workload
ma-WF-ACFPD003
ps-WF-ACFPD004Wildfire Threat American
Canyon Fire
Protection
District
Limited staffing (0.992 firefighters per 1,000
population vs. national avg. 1.54) and
resources reduces surge capacity for wildfire
response during multi-alarm incidents.
ma-AH-ACFPD001, ma-AHACFPD-002, maWF-ACFPD-002,
ma-WF-ACFPD003
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6.6 Mitigation Strategy
This section provides the framework for how ACFPD 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 district’s prioritized mitigation actions. Together, these elements demonstrate how ACFPD 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 ACFPD, the strategy outlined in this annex reflects the outcomes of the countywide planning process while also addressing the district’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 wildfire, earthquakes and severe weather, 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 district, county, and regional planning mechanisms. Each action identifies responsible parties, potential funding sources, and the resources needed for implementation.

For ACFPD, this strategy provides a framework for strengthening resilience by combining district-led initiatives, such as infrastructure improvements, and community preparedness, with regional coordination through the MJHMP. By advancing these efforts in alignment with the Master Plan and other local planning documents, ACFPDenhances 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 6.6.1, Capabilities and Opportunities, provides a summary of the city’s capacity to address natural hazards.
▪ Section 6.6.2, Mitigation Action Plan, presents the district’s prioritized actions to guide implementation in coordination with countywide strategies.

Aligning the Action Plan
This section connects ACFPD’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.

The section begins with a summary of ACFPD’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.

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6.6.1 Capabilities & Opportunities
This section provides a detailed assessment of the district’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
ACFPD operates within a dynamic environment shaped by continued development, regional population growth, and evolving hazard conditions. Effective hazard mitigation planning requires the district to balance current operational demands with long-term community expansion, infrastructure changes, and emerging climate-driven risks. As American Canyon continues to develop, land use decisions, construction patterns, and infrastructure investments play a central role in shaping both hazard exposure and emergency response needs.

Growth within the District has historically been associated with residential expansion, commercial development, and the buildout of previously undeveloped areas. New development can strengthen community resilience through modern building codes, ignition-resistant construction, improved water supply systems, and enhanced roadway networks. At the same time, growth can introduce new vulnerabilities by expanding the built environment into areas subject to wildfire, flooding, slope instability, or other hazards. The district’s planning framework must therefore recognize that development simultaneously reduces and redistributes risk.

Hazard-informed planning is a key mechanism for managing this balance. Integration of hazard data into land use planning, development review, and capital improvement programming allows ACFPD and partner agencies to proactively address risk. This includes consideration of wildfire severity zones. Early incorporation of hazard mitigation principles into project design can reduce future losses, minimize emergency response challenges, and limit long-term operational strain on district resources.

From an emergency services perspective, growth directly influences service demand, response times, and infrastructure requirements. Increased population density, expanded residential neighborhoods, and new commercial centers generate additional calls for service while also affecting travel patterns, evacuation dynamics, and water supply distribution. Fire station siting, apparatus deployment, and staffing models must evolve alongside development patterns to maintain consistent levels of service.

Infrastructure planning is equally critical. Transportation corridors, bridges, utilities, and water systems form the backbone of both hazard resilience and emergency response capability. Growth-related infrastructure improvements can enhance redundancy and system reliability; however, hazard exposure such as flooding, seismic events, or wildfire can disrupt these networks. Coordinated planning helps ensure that infrastructure investments support both community development and hazard mitigation objectives.

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uncertainty into long-term planning assumptions. Areas previously considered low-risk may experience changing hazard profiles over time, reinforcing the need for adaptive planning approaches.

ACFPD’s role within this planning landscape is inherently collaborative. While land use authority resides primarily with the City of American Canyon, the district contributes through development review, fire code enforcement, defensible space programs, emergency response planning, and public safety coordination.

Participation in regional hazard mitigation efforts, interagency planning initiatives, and capital improvement discussions allows the district to integrate hazard considerations into broader community decisions.

Development & Hazard Considerations
Development patterns within the ACFPD play a central role in shaping hazard exposure, emergency response demands, and long-term community resilience. As American Canyon continues to grow, the interaction between land use decisions and natural hazards becomes increasingly important. New development influences not only where risk exists, but also how that risk is managed through design, construction standards, infrastructure investment, and emergency planning.

American Canyon’s geographic setting creates a complex hazard environment. The district encompasses low-lying bayfront areas, established urban neighborhoods, transportation corridors, and hillside or wildland interface zones. Each of these environments presents distinct hazard considerations. Expansion into wildland-adjacent areas can increase wildfire exposure, while development within low-lying or coastal areas may elevate flood and sea level rise vulnerability. Similarly, construction near slopes or areas of weak soil introduces potential concerns related to slope instability or seismic ground failure.

Modern development, however, also presents significant opportunities to reduce risk. California’s building and fire codes require ignition-resistant construction, defensible space measures, fire flow provisions, and seismic design standards that substantially improve structural performance compared to older building stock. New subdivisions typically incorporate improved roadway widths, hydrant spacing, water supply infrastructure, and emergency access features that enhance response capability and evacuation efficiency.

Despite these advances, development can redistribute rather than eliminate hazard exposure. Increased density elevates potential consequences when events occur. Concentrated populations, expanded infrastructure networks, and greater asset values increase the scale of potential losses associated with earthquakes, flooding, wildfire, or severe weather events. Growth also influences evacuation complexity, traffic congestion, and emergency resource allocation during large-scale incidents.

Wildfire considerations are particularly relevant at the edges of developed areas. As residential and commercial growth approaches open space or vegetated lands, the WUI becomes a key planning focus. Fuel management, defensible space enforcement, ignition-resistant construction, and emergency access design are essential components of risk reduction. Strategic buffers, vegetation management programs, and landscape design standards can significantly reduce structure ignition potential.

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Flood and stormwater hazards present a different but equally important challenge. Development alters drainage patterns, increases impervious surfaces, and can intensify localized flooding if not carefully managed. Stormwater systems, detention facilities, and grading design must account for both current conditions and projected climate variability. Sea level rise introduces an added dimension for low-lying areas, requiring long-term planning for drainage, infrastructure elevation, and potential future inundation scenarios.

From an emergency services perspective, growth directly affects operational capacity. Increased development expands the district’s service area, modifies travel demand, and alters response time dynamics. Fire station coverage, apparatus deployment, staffing models, and water supply distribution must evolve alongside development patterns. Infrastructure investments that support redundancy, circulation efficiency, and system reliability enhance both hazard resilience and emergency response effectiveness.

ACFPD’s involvement in development is primarily exercised through fire code enforcement, development review, water supply and access requirements, defensible space programs, and interagency coordination.

Early integration of hazard mitigation principles into project design represents one of the most effective risk reduction strategies. Addressing hazards at the planning stage is consistently more cost-effective than retrofitting or post-disaster recovery.

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 district’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 ACFPD 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.

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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 ACFPD summarizes the various types of capabilities it has for hazard mitigation currently. The assessment also identifies opportunities to integrate, expand, and improve the city’s capabilities for future hazard mitigation. Table 6-6 provides a comprehensive list of capabilities and identifies the current status, current mitigation use, and future opportunities.

Planning & Regulatory
ACFPD’s planning and regulatory capabilities include strong operational practices, particularly in fire prevention, inspections, defensible space enforcement, weed abatement, public education, and code enforcement. The city’s adoption of CAL FIRE Fire Hazard Severity Zone maps and Chapter 7A ignitionresistant construction standards further strengthens the regulatory framework for wildfire risk reduction.

Several planning areas remain informal or are handled through partner agencies. ACFPD does not currently maintain a formal Capital Improvements Program, Annual Fire Prevention Plan, non-structural seismic safety program, Earthquake Modernization Plan, Floodplain Response Plan, Drought Management Plan, or independent Community Wildfire Protection Plan. The District’s Master Plan identifies several of these gaps and recommends greater formalization, especially for capital planning and fire prevention activities.

Stormwater, floodplain, groundwater, climate adaptation, and drought planning are primarily managed by the city, County, or regional agencies. However, ACFPD supports hazard resilience through emergency response, participation in the Napa County CWPP, engagement with Napa Firewise programs, and ongoing public education. Opportunities exist to strengthen resilience by developing structured planning documents, formalizing hazard-specific outreach, and better integrating wildfire, seismic, flood, heat, and drought preparedness into District programs.

Future integration of the MJHMP will occur through various processes and mechanisms outlined across multiple mitigation actions (Table 6-7). Key opportunities for future hazard mitigation integration with the ACFPD’s existing planning mechanisms include incorporating the updated risk assessment, hazardspecific vulnerability findings, and projected climate change impacts into the Severe Weather Response Protocol Development (ma-SW-ACFPD-001), Storm Access Route Reliability Mapping (ma-SW-ACFPD-002), Wildfire Evacuation Support & Access Reliability (ma-WF-ACFPD-002), and the Wildfire Public Information & Smoke Impact Program (ma-WF-ACFPD-003).

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Administrative & Technical
ACFPD’s administrative and technical capacity reflects the structure of a small to mid-sized fire district that prioritizes core emergency response operations while relying on partner agencies or shared resources for specialized functions. The district maintains strong operational capability but does not have dedicated internal staff for several technical and administrative roles.

ACFPD does not employ a dedicated Emergency Manager, civil engineer, GIS specialist, Public Information Officer, outreach specialist, or grant manager. Emergency management functions are primarily handled by the City of American Canyon and Napa County OES, while engineering, infrastructure, drainage, roadway, and GIS support are provided through City and County resources. Public outreach is conducted through reserve personnel and shared City support.

Although this structure is consistent with ACFPD’s operational mission, it may limit internal capacity for hazard mitigation planning, sustained public education, multilingual risk communication, detailed vulnerability analysis, and competitive grant pursuit. Opportunities exist to strengthen resilience by expanding shared staffing support, formalizing administrative roles, and improving grant coordination for mitigation, equipment, and long-term resilience projects.

Warning Systems & Services
ACFPD relies on regional, county, and city-operated warning systems for public notification and emergency communication. The District does not independently operate hazard-specific alert systems but coordinates with the City of American Canyon, Napa County, and regional partners to support consistent emergency messaging.

General emergency notifications are provided through systems such as Everbridge, Nixle, social media, and shared public communication channels. Flood alerts are managed by the City of American Canyon and the Napa County Flood Control and Water Conservation District, while ACFPD responds operationally to flood incidents.

Wildfire warning and evacuation communication are supported through regional tools such as Zonehaven and Everbridge. Although ACFPD plays a key role in wildfire response, evacuation alerts and public warnings are typically coordinated through law enforcement and emergency management agencies.

Geological hazard alerts, including earthquake and landslide notifications, are managed through state, federal, and regional systems such as ShakeAlert, with ACFPD focused on response and public safety operations after an event.

Fiscal
ACFPD’s fiscal capabilities support core operations, capital improvements, and some hazard mitigation activities through voter-approved revenues and development-related fees. The district benefits from a voter-approved Fire Service Fee, as well as development impact fees that help fund growth-related facility, CAL OES SUBMITTAL - JUNE 2026
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apparatus, and equipment needs. The 2023 Development Impact Fee Study further strengthened this capacity by establishing a Fire Capital Facilities Fee for new development.

ACFPD does not generate utility service fees or stormwater-related revenues, as those functions fall outside the district’s authority and are managed by the City of American Canyon or Napa County. The district has not issued general obligation bonds, but it has explored other financing tools, such as Community Facilities District or Mello-Roos mechanisms, that could support future large-scale infrastructure or facility investments.

Capital improvements are currently funded primarily through Fire Service Fee revenues and development impact fees rather than a formal Capital Improvements Program. While this provides flexibility, the lack of a structured CIP and formal risk-based spending policies may limit long-term planning for hazard mitigation, facility modernization, and infrastructure resilience.

Education & Outreach
ACFPD’s education and outreach capabilities include established community engagement practices, social media communication, public safety messaging, and partnerships that support wildfire preparedness, emergency awareness, and life safety risk reduction. The District maintains an online and social media presence, while also relying on the City of American Canyon and regional partners such as Napa Firewise to share broader hazard education and preparedness information.

ACFPD participates in annual public safety events, including National Night Out, fire station open houses, school visits, and similar outreach activities. These events provide opportunities to educate residents on fire safety, defensible space, emergency preparedness, and hazard awareness. The District also responds to public inquiries through informal channels such as phone calls, station visits, and direct staff interaction.

While outreach is active, several functions are not yet formalized. ACFPD does not currently maintain a comprehensive hazard education platform, routine public safety newsletter, structured technical assistance program, or formal distribution strategy for printed hazard materials at public-facing facilities.

Opportunities exist to strengthen outreach by expanding hazard-specific web content, improving printed material distribution, formalizing technical assistance, and continuing collaboration with Napa Firewise, Fire Safe Councils, the Resource Conservation District, and reserve personnel.

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.

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Table 6-6: ACFPD Capabilities and Opportunities Assessment HMP Integration Notes / Additional Detail
Resource Status
Current
Mitigation
Use
Future
Opportunity
Planning and Regulatory
Capabilities
Hazard Reduction Programs
(Annually Conducted)
Capital Improvements Program
(CIP) or Plan Green Green Green CIP and Master Plan
Annual Fire Prevention Plan
Green Green Green
ACFPD conducts inspections, weed
abatement, and public education but lacks a
formal written prevention plan. Master Plan
recommends formalizing these activities.

District enforces state Fire & Building Codes
and the District has adopted CAL FIRE FHSZ
maps and Chapter 7A (where applicable)
Seismic Safety Program (Nonstructural)
Orange Orange Green
No formal non-structural seismic safety
program exists. Station furnishings and
equipment are not part of a district-wide
anchoring protocol.

Earthquake Modernization Plan
(Building Safety)
Orange Orange Yellow
No district-wide plan for structural seismic
upgrades. Station 211 received seismic
improvements in 2003, but no formal
modernization roadmap exists.

Stormwater Management
Program (Annual Inspections) Orange Orange Orange
Stormwater planning is under City/County
jurisdiction. ACFPD has no dedicated
stormwater inspection program
Hazard Plans and Programs
Floodplain Response Plan
Orange Orange Orange
Flood planning is led by the City and Napa
County Flood Control; ACFPD has no
operational flood response plan.

Community Wildfire Protection
Plan (CWPP) Green Green Green CWPP update with Napa Firewise/participates in the Napa County CWPP.

Ground Water Management
Planning / Plans Orange Orange Orange Groundwater management is handled by local water agencies; ACFPD has no role.

Climate Action Plan
Orange Orange Green City has a CAP; ACFPD is not a direct participant.

Drought Mgmt/ Contingency
Plan Orange Orange Green District has no drought plan.

FireWise Communities within
District Yellow Yellow Green None in American Canyon currently; many in Napa County
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HMP Integration Notes / Additional Detail
Resource Status
Current
Mitigation
Use
Future
Opportunity
Hazard-Related Public Outreach
Program Yellow Yellow Green Outreach occurs but is not structured around hazards.

Administrative and
Technical
Staff Capacity
Emergency Manager
Orange Orange Green
ACFPD has no dedicated emergency manager;
responsibilities handled by City and County
OES.

Civil Engineer
Orange Orange Orange
Civil engineering functions (e.g., water
systems, drainage, access roads) fall under
City or County Public Works. ACFPD does not
employ or contract a civil engineer.

Dedicated Public Outreach
Personnel Green Green Green Admin Staff conduct outreach GIS Specialist and Capability
Green Green Green Admin Staff plus City/County mapping.

Grant Manager, Writer, or
Specialist Green Green Green Admin Staff
Other

N/A N/A N/A
Warning Systems/Services
General
Yellow Yellow Green District relies on Nixle/Everbridge and shared social media
Flood
Orange Orange Orange
Flood alerting and warning responsibilities fall
under City of American Canyon and Napa
County Flood Control and Water Conservation
District. ACFPD is not responsible for operating
or activating flood-specific warning systems.

Wildfire
Yellow Yellow Green District uses Zonehaven/Everbridge but does not issue its own alerts.

Geological Hazards
Orange Orange Orange District does not operate geological hazard warning systems.

Fiscal Capabilities
Financial Resources for
Hazard Mitigation
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HMP Integration Notes / Additional Detail
Resource Status
Current
Mitigation
Use
Future
Opportunity
Levy for Specific Purposes with
Voter Approval Green Green Yellow
District maintains a voter-approved Fire
Service Fee and collects development impact
fees.

Utilities Fees
Orange Orange Orange ACFPD does not operate any utility lines or charge utility-based service fees.

System Development Fee
Green Green Green
A 2023 Development Impact Fee Study
established a Fire Capital Facilities Fee, which
is assessed per square foot of new
development. These fees fund apparatus
purchases and station expansions needed to
support growth. Periodic updates to the fee
program can ensure funding keeps pace with
inflation and construction costs.

General Obligation Bonds to
Incur Debt
Orange Orange Green
ACFPD has not issued general obligation
bonds. The District could consider this tool to
fund long-term facility upgrades or new
station construction, pending voter approval.

Special Tax Bonds to Incur Debt
Yellow Yellow Green
The existing Fire Mitigation Fee operates
similarly to a special tax on new construction.

ACFPD has explored Community Facilities
District (CFD) or Mello-Roos financing options
for larger development areas. These
mechanisms could be expanded to fund
hazard mitigation projects tied to growth.

Withheld Spending in HazardProne Areas Orange Orange Green No risk-based spending policies exist.

Stormwater Service Fees
Orange Orange Orange
Stormwater planning and funding fall under
the jurisdiction of the City of American
Canyon and Napa County. ACFPD does not
charge or manage stormwater-related fees.

Capital Improvement Project
Funding Green Green Green CIP and Master Plan
Education / Outreach
Capabilities
Education/Outreach
Resources
Website Dedicated to Hazard
Topics Orange Orange Green ACFPD maintains a standalone page but relies on City webpage for hazard education.

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HMP Integration Notes / Additional Detail
Resource Status
Current
Mitigation
Use
Future
Opportunity
Dedicated Social Media
Yellow Yellow Green
ACFPD has dedicated social media and in
addition shares posts through City social
media and occasionally cross-posts content
via Napa Firewise or the City’s emergency
alerts.

Hazard Info. Avail. at Library/
Planning Desk
Orange Orange Green
Hazard and preparedness materials are not
known to be regularly stocked or distributed
through the public library or City Planning
counter. Could collaborate with Napa County
Library or Planning Dept. to distribute
defensible space handouts, wildfire zone
maps, and Ready-Set-Go materials.

Annual Public Safety Events
Green Green Green ACFPD participates in National Night Out, fire station open houses, and school visits.

Ability to Field Public Tech.

Assistance Requests Yellow Yellow Green Handled informally via calls/visits.

Public Safety Newsletters or
Printed Outreach Green Green Green News Ladder monthly publication Fire Safe Councils
Yellow Yellow Green Participation occurs but Council is not formalized.

Resource Conservation Districts
Yellow Yellow Green Coordination occurs but is project-specific.

Other

N/A N/A N/A
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6.6.2 American Canyon Fire Protection District Mitigation Action Plan ACFPD’s mitigation
actions were developed
through a collaborative
process informed by the
updated risk
assessment, local
priorities, and extensive
stakeholder
engagement. As a firsttime participant in a
hazard mitigation plan,
ACFPD did not have any
existing mitigation
actions from a prior plan
to evaluate. Therefore,
all mitigation actions
identified in this
planning cycle are
newly developed based
on the district’s updated
risk assessment, local capabilities, and areas of concern identified during stakeholder engagement and interagency collaboration. These new actions were crafted to address the district’s highest priority hazards, align with FEMA’s hazard mitigation guidance, and reflect local infrastructure vulnerabilities and water resource challenges. The development of these mitigation strategies marks an important step in integrating resilience into the district’s operations and long-term planning. All mitigation actions are documented in Volume 2, Table 6-7. 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 ACFPD’s most significant hazards, including wildfire, earthquake, severe weather, and climate change. 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 ACFPD is documented in Table 6-7, 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 6-17) that links the strategy to its associated hazard and supports consistent monitoring and reporting.

Figure 6-17: Mitigation Action Number Key
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ACFPD’s approach recognizes that some hazards are most effectively addressed through regional efforts.

Weather and wildfire risk reduction often extend beyond the district’s boundaries and require collaboration with county, regional, and state partners. By aligning local actions with regional strategies, ACFPD helps to consolidate resources, maximize funding opportunities, and ensure that mitigation projects achieve the greatest benefit for San Pablo Bay, the Napa Valley, and the wider Napa County community.

Collectively, these mitigation actions provide a roadmap for reducing hazard risk, protecting vulnerable populations, and strengthening the long-term resilience of ACFPD.

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Table 6-7: ACFPD 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-AHACFPD-001All Hazard ES -
Emergency
Services
2026 American
Canyon
Fire
Protection
District
Staffing
Surge &
Battalion
Chief
Capacity
Plan
Develop phased staffing and Battalion Chief
coverage strategy to increase response capacity
for large, multi-hazard incidents.

Administrative
Staff
Medium Medium 1-3 Years Capacity /
Capability
Building

HMGP / BRIC ,
General Fund
High ps-EQ-ACFPD-001, ps-EQACFPD-003, ps-EQ-ACFPD004, ps-WF-ACFPD-004 ma-AHACFPD-002All Hazard PRV -
Prevention
2026 American
Canyon
Fire
Protection
District
Reserves &
Revenue
Stability
Assessment
Conduct a detailed fiscal resilience analysis to
protect District operations from future declines
in property tax or strike team revenue volatility.

Administrative
Staff
Low Medium 1-3 Years Capacity /
Capability
Building

HMGP / BRIC ,
General Fund
Medium ps-EQ-ACFPD-004, ps-SWACFPD-003, ps-WF-ACFPD004 ma-EQ-ACFPD001Earthquake PPRO -
Property
Protection
2026 American
Canyon
Fire
Protection
District
Station 211
Seismic
Vulnerability
Reduction
Planning
Develop a seismic vulnerability assessment and
replacement plan for undersized, outdated
Station 211 to maintain operational readiness.

Administrative
Staff
Low Medium 1-3 Years Project HMGP / BRIC ,
General Fund
High ps-EQ-ACFPD-002
ma-EQ-ACFPD002Earthquake PPRO -
Property
Protection
2026 American
Canyon
Fire
Protection
District
Earthquake
Equipment
Securing &
Continuity
Upgrades
Install equipment tie-downs, secure storage, and
backup communications to prevent damage
during strong shaking.

Administrative
Staff
Low High 3-5 Years Project HMGP / BRIC ,
General Fund
Medium ps-EQ-ACFPD-001, ps-EQACFPD-003
ma-SWACFPD-001Severe
Weather
All ES -
Emergency
Services
2026 American
Canyon
Fire
Protection
District
Severe
Weather
Response
Protocol
Development
Create new operational protocols for high-wind,
atmospheric river, and storm-related hazards,
addressing access delays, safety precautions,
and resource deployment.

Administrative
Staff
Low Medium 1-3 Years Capacity /
Capability
Building

HMGP / BRIC ,
General Fund
High ps-SW-ACFPD-003, ps-SWACFPD-001, ps-SW-ACFPD002
ma-SWACFPD-002Severe
Weather
All PRV -
Prevention ,
ES -
Emergency
Services
2026 American
Canyon
Fire
Protection
District
Storm
Access Route
Reliability
Mapping
Identify and pre-map alternative access routes
during storm-related road closures or flooding to
ensure operational continuity.

Administrative
Staff
Low Medium 3-5 Years Capacity /
Capability
Building

HMGP / BRIC ,
General Fund
Medium ps-SW-ACFPD-002, ps-SWACFPD-001
ma-WFACFPD-001Wildfire NRP - Natural
Resource
Protection
2026 American
Canyon
Fire
Protection
District
Targeted
Greenbelt
Fuels
Reduction
Program
Implement recurring fuels reduction focused on
eucalyptus stands, open-space greenbelts, and
high-risk areas adjacent to adult/childcare
facilities.

Administrative
Staff
Medium High 1-3 Years Project HMGP / BRIC ,
CalFIRE , General
Fund
High ps-WF-ACFPD-001, ps-WFACFPD-002
ma-WFACFPD-002Wildfire PRV -
Prevention
2026 American
Canyon
Fire
Protection
District
Wildfire
Evacuation
Support &
Access
Reliability
Improve emergency access near high-risk
facilities by pre-planning ingress/egress,
signage, and clearing overgrown roadside
vegetation.

Administrative
Staff
Low Medium 3-5 Years Project HMGP / BRIC ,
General Fund
Medium ps-WF-ACFPD-004, ps-WFACFPD-002, ps-WF-ACFPD001 ma-WFACFPD-003Wildfire PE&A - Public
Education &
Awareness
2026 American
Canyon
Fire
Protection
District
Wildfire
Public
Information
& Smoke
Impact
Program
Launch a proactive public-information program
focused on smoke impacts, community
preparedness, and local outdoor fuel hazards.

Administrative
Staff
Low Medium 3-5 Years Capacity /
Capability
Building

HMGP / BRIC ,
CalFIRE , General
Fund
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Section 7. Howell Mountain Mutual Water
Company
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Napa County
2026 Multi-Jurisdictional Hazard Mitigation Plan Update Howell Mountain Mutual Water Company (HMMWC)
Special Agency Annex
Section 7. Howell Mountain Mutual Water Company..........................................................7-1

7.1 Scope & Purpose ......................................................................................................................................................................7-1

7.2 Jurisdictional Setting............................................................................................................................................................7-1

7.2.1 Geography & Climate ..................................................................................................................................................7-3

7.2.2 Demographics & Vulnerable Populations...........................................................................................................7-6

7.2.3 Economy........................................................................................................................................................................7-20

7.2.4 Growth Trends & Future Development.............................................................................................................. 7-21

7.3 Planning Process .................................................................................................................................................................7-22

7.3.1 Public Input & Draft Review ...................................................................................................................................7-24

7.4 What’s New.............................................................................................................................................................................7-25

7.4.1 Mitigation Activities .................................................................................................................................................7-25

7.4.2 Mitigation Successes................................................................................................................................................7-26

7.5 Risk Assessment..................................................................................................................................................................7-28

7.5.1 Hazard Screening & Prioritization ......................................................................................................................7-28

7.5.2 Vulnerability to Specific Hazards........................................................................................................................7-32

7.5.3 Climate Change Impacts & Vulnerable Populations....................................................................................7-48

7.5.4 Hazard Problem Statements................................................................................................................................. 7-49

7.6 Mitigation Strategy .............................................................................................................................................................7-53

7.6.1 Capabilities & Opportunities..................................................................................................................................7-54

7.6.2 HMMWC Mitigation Action Plan..........................................................................................................................7-65

7.6.1 Status of Previous Mitigation Actions...............................................................................................................7-68 CAL OES SUBMITTAL - JUNE 2026
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List of Figures
Figure 7-1: HMMWC Geographic Overview Map....................................................................................................................7-5 Figure 7-2: HMMWC Median Household Income Map ........................................................................................................7-9 Figure 7-3: HMMWC Poverty Status Map................................................................................................................................7-10 Figure 7-4: HMMWC Housing Occupancy Map.....................................................................................................................7-11 Figure 7-5: HMMWC Dependent Age Groups Map ..............................................................................................................7-13 Figure 7-6: HMMWC Disabled Elderly Map............................................................................................................................7-14 Figure 7-7: HMMWC Race and Ethnicity Map.......................................................................................................................7-16 Figure 7-8: HMMWC Spanish-Speaking Households Map...............................................................................................7-17 Figure 7-9: HMMWC CDC Social Vulnerability Index Map ..............................................................................................7-19 Figure 7-10: HMMWC Risk Assessment Matrix................................................................................................................... 7-30 Figure 7-11: Exposure Summary – HMMWC Wildfire Risk............................................................................................. 7-34 Figure 7-12: Exposure Summary – HMMWC Dam Failure Risk.....................................................................................7-37 Figure 7-13: Exposure Summary – HMMWC Earthquake Risk (M7.1 Hunting Creek–Berryessa).................. 7-40 Figure 7-14: Exposure Summary – HMMWC Earthquake Risk (M6.7 West Napa)..................................................7-41 Figure 7-15: Drought Severity Timeline 2000-2026............................................................................................................ 7-44 Figure 7-16: Mitigation Action Number Key ..........................................................................................................................7-65 List of Tables
Table 7-1: HMMWC Planning Team and Steering Group Members..............................................................................7-23 Table 7-2: HMMWC Planning Team Meetings..................................................................................................................... 7-24 Table 7-3: HMMWC Document Review of Potential Hazards ........................................................................................ 7-29 Table 7-4: HMMWC Hazards Prioritization Summary.......................................................................................................7-31 Table 7-5: Drought Classifications and Impacts ................................................................................................................. 7-43 Table 7-6: HMMWC Hazard Problem Statements............................................................................................................... 7-49 Table 7-7: HMMWC Capabilities and Opportunities Assessment................................................................................ 7-60 Table 7-8: HMMWC Mitigation Action Plan.......................................................................................................................... 7-67 Table 7-9: HMMWC Status of Previous Mitigation Actions............................................................................................ 7-68 CAL OES SUBMITTAL - JUNE 2026
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Adoption Resolution
To comply with the Federal Disaster Mitigation Act of 2000 (DMA 2000), The Howell Mountain Mutual Water Company Board of Directors 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 district’s commitment to reducing the impacts of natural hazards within its jurisdiction and across Napa County.

A copy of the district’s adoption record is provided on the following pages. Adoption records for all jurisdictions are summarized in Volume 1, Table ES-1.

ADOPTION RECORD TO BE INSERTED UPON COMPLETION.

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Section 7. Howell Mountain Mutual Water Company

7.1 Scope & Purpose
This Jurisdictional Annex for the Howell Mountain Mutual Water Company (HMMWC) of the 2026 Napa County MultiJurisdictional Hazard Mitigation Plan (MJHMP) details the hazard mitigation planning elements specific to the district’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 district. This annex provides additional information specific to the district, with a focus on hazard identification and risk assessment, vulnerability assessment, problem statements, mitigation strategy, and capabilities assessment. Below are HMMWC’s Points of Contact:

Primary Point of Contact Alternate Point of Contact
Shannon Damonte, Administrative Manager
Howell Mountain Mutual Water Company, Inc
P.O. Box 9
Angwin, CA 94508
Telephone: (707) 965-2205
email: [email protected]
Tanner Hiers, General Manager
Howell Mountain Mutual Water Company, Inc
P.O. Box 9
Angwin, CA 94508
Telephone: (707) 965-2205
email: [email protected]

7.2 Jurisdictional Setting
HMMWC is a California nonprofit mutual benefit corporation that provides potable water service to the Angwin and Howell Mountain area of Napa County. The company operates as a member-owned mutual water utility serving a predominantly residential population located within a rural, mountainous environment. The service area is characterized by forested lands, steep slopes, narrow and winding roadways, and limited transportation access, all of which influence both day-to-day operations and hazard vulnerability. Unlike municipal utilities, HMMWC functions as an independent entity governed by its membership and Board of Directors, with organizational authority, financial decision-making, and operational direction established through its adopted bylaws.

HMMWC’s governance structure reflects its status as a nonprofit mutual benefit corporation organized under California law. Company assets, including land, reservoirs, treatment facilities, and distribution infrastructure, are held for the benefit of the membership and are used primarily for water supply, treatment, storage, and delivery functions. The Board of Directors is responsible for overseeing company policies, financial management, capital improvements, and regulatory compliance. Regular Board meetings are publicly noticed and conducted in a manner that supports transparency and member participation.

Operational management is carried out by company staff responsible for treatment plant operations, CAL OES SUBMITTAL - JUNE 2026
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watershed and reservoir management, distribution system maintenance, water quality monitoring, and customer service functions.

The HMMWC service area is situated within a rural mountain setting that significantly shapes the system’s operational and hazard context. Development patterns consist largely of low-density residential uses interspersed with forested and watershed lands. The mountainous terrain presents inherent challenges related to infrastructure construction, maintenance, and emergency access. Steep slopes and complex topography contribute to increased exposure to slope instability, erosion, and storm-related impacts.

Limited roadway access and constrained evacuation routes further amplify the importance of reliable utility service during emergencies. As a lifeline utility, HMMWC plays a critical role in supporting residential occupancy, public health, and fire protection capabilities within the community.

HMMWC’s water supply system relies on a combination of surface water reservoirs and groundwater wells.

The company owns and manages a watershed comprising approximately 263 acres, within which nine interconnected reservoirs provide raw water storage. These reservoirs, along with multiple intake structures and groundwater wells, form a distributed water supply network typical of small mountain utilities. The system’s reliance on stored surface water makes reservoir levels and watershed conditions primary determinants of water availability and system reliability. Variations in precipitation, extended drought conditions, and watershed disturbances therefore have direct implications for operational continuity.

The regulatory environment governing HMMWC includes oversight by the California Division of Drinking Water and compliance with federal Safe Drinking Water Act requirements. Water quality monitoring, treatment standards, and reporting obligations are documented annually through Consumer Confidence Reports. Source water assessments have identified potential vulnerabilities associated with surrounding land uses, including agricultural activities located near drinking water sources. Maintaining regulatory compliance under varying environmental conditions requires ongoing system monitoring, infrastructure maintenance, and adaptive operational strategies.

HMMWC’s jurisdictional setting presents several hazard-relevant operational considerations. The system’s dependence on watershed-derived surface water introduces sensitivity to drought conditions, reduced snowpack and precipitation, and climate variability. Prolonged dry periods directly affect reservoir storage capacity, prompting the adoption of staged drought response measures designed to conserve water and maintain service reliability. The forested mountain environment also results in elevated wildfire exposure, with potential impacts including damage to reservoirs, intake structures, and distribution infrastructure, as well as post-fire water quality degradation and increased sedimentation. Watershed management activities, including vegetation and fuel reduction efforts, represent ongoing strategies to reduce wildfire-related risks.

Infrastructure vulnerability is further influenced by the region’s terrain and geologic conditions. Steep slopes increase the potential for landslides, slope failures, and erosion events that may disrupt pipelines, access routes, and treatment facilities. Seismic hazards present an additional risk factor, as earthquake events have the potential to damage reservoirs, pipelines, and mechanical systems.

Power reliability represents another critical factor within HMMWC’s operational context. Treatment, pumping, and control systems depend on electrical infrastructure susceptible to wildfire-related outages, CAL OES SUBMITTAL - JUNE 2026
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storm damage, and Public Safety Power Shutoff events. Interruptions to power service can directly affect water production, storage, and distribution functions, highlighting the interconnected nature of utility systems and hazard impacts. Operational planning and equipment upgrades are therefore essential components of maintaining continuity under adverse conditions.

HMMWC’s location within Napa County and the State of California are shown in Figure 7-1. ▪ Year of Incorporation: 1985
▪ 2023 Population Served: ~1,617 (CAS 5-Year, 2018-2023) ▪ Coverage Area: ~263 acres

7.2.1 Geography & Climate
HMMWC operates within the Howell Mountain / Angwin area of Napa County, a region defined by rugged mountainous terrain, steep slopes, and heavily forested landscapes. The service area is situated at higher elevations relative to the Napa Valley floor, resulting in cooler average temperatures but also increased exposure to terrain-driven hazards. The topography is characterized by narrow ridgelines, incised drainages, and complex slope systems that influence watershed behavior, infrastructure placement, and system maintenance activities. Steep gradients and variable geologic conditions contribute to localized slope instability, erosion, and drainage challenges, all of which have implications for pipelines, reservoirs, and access routes.

The region’s geography plays a central role in shaping HMMWC’s water supply and operational framework.

The company’s watershed lands, reservoirs, and intake structures are embedded within a natural environment dominated by mixed forest, woodland, and wildland vegetation. These landscapes support raw water capture and storage but also introduce environmental sensitivities and hazard exposures. Dense vegetation, limited defensible space in some areas, and constrained roadway access collectively elevate wildfire risk and complicate emergency response operations. The mountainous setting further restricts infrastructure redundancy options, as steep terrain and limited developable corridors constrain pipeline routing and system expansion opportunities.

Access throughout the service area is primarily provided by winding, two-lane mountain roadways that are susceptible to disruption from landslides, fallen trees, wildfire events, and severe weather. These transportation limitations affect both routine maintenance operations and post-disaster recovery activities.

In emergency conditions, geographic isolation may delay repair efforts, equipment mobilization, and mutual aid access. As a result, the physical landscape directly influences system resilience, emphasizing the importance of preventative maintenance, localized storage capacity, and hazard-aware infrastructure planning.

The climate of the Howell Mountain region is consistent with a Mediterranean pattern typical of much of California, characterized by cool, wet winters and warm, dry summers. Precipitation is highly seasonal, with the majority of annual rainfall occurring between late fall and early spring. Summer months are typically marked by prolonged dry conditions, low humidity, and elevated temperatures, contributing to increased wildfire potential and heightened stress on water supply systems. Interannual variability in precipitation, CAL OES SUBMITTAL - JUNE 2026
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including multi-year drought cycles, is a defining feature of the regional climate and a primary driver of water resource management challenges.

Drought conditions represent a recurring and significant influence on HMMWC operations. Reduced rainfall and diminished watershed recharge directly affect reservoir storage levels, raw water availability, and system reliability. Extended dry periods may necessitate staged conservation measures, demand management strategies, and operational adjustments designed to preserve limited water supplies. Climate variability, including fluctuations associated with El Niño and La Niña patterns, can result in alternating periods of above-average precipitation and severe drought, increasing uncertainty in long-term water planning.

Seasonal climate conditions also intensify wildfire risk within the service area. Hot, dry summers combined with periodic wind events create conditions conducive to rapid fire spread. Wildfire impacts may include direct damage to watershed lands, reservoirs, intake structures, electrical infrastructure, and distribution systems. Post-fire conditions can further degrade water quality through increased sedimentation, ash transport, and altered runoff patterns. These climate-driven hazard interactions underscore the interconnected nature of environmental processes and utility system vulnerability.

Emerging climate trends, including rising average temperatures, increased frequency of extreme heat events, and shifting precipitation patterns, introduce additional considerations for long-term system resilience. Higher temperatures may increase water demand, accelerate reservoir evaporation, and extend wildfire seasons. Changes in storm intensity and rainfall distribution may contribute to both flooding and erosion hazards, affecting infrastructure stability and watershed function. Collectively, these geographic and climatic factors establish the environmental context within which HMMWC must operate, adapt, and plan for future hazard conditions.

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Figure 7-1: HMMWC Geographic Overview Map
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7.2.2 Demographics & Vulnerable Populations
HMMWC provides potable water service to a small, primarily residential population located within the Angwin and Howell Mountain area of Napa County. The service area is characterized by low-density development patterns typical of rural mountain communities, where residential parcels are dispersed across steep terrain and heavily forested landscapes. The population served by HMMWC reflects a mix of full-time residents, seasonal occupants, rental properties, and institutional uses associated with the Angwin community. As a member-owned mutual water company, the customer base largely consists of property owners who hold water rights, along with tenants residing on served parcels.

The demographic composition of the service area is influenced by its geographic setting. Rural mountain communities often exhibit population characteristics distinct from urbanized areas, including smaller household clusters, reduced infrastructure redundancy, and greater dependence on localized utility systems. These conditions increase the importance of reliable water service for maintaining habitability, sanitation, and fire protection capabilities. The dispersed nature of development also affects emergency response dynamics, evacuation logistics, and post-disaster recovery timelines.

Several population groups within the HMMWC service area may experience heightened vulnerability during hazard events. Elderly residents, individuals with disabilities, and persons with access or functional needs may face increased challenges related to evacuation, mobility, and continuity of essential services.

Interruptions to potable water supply, whether caused by drought, wildfire, seismic events, or infrastructure damage, may disproportionately affect individuals requiring medical care, sanitation support, or temperature regulation. Rural mountain environments can amplify these challenges due to limited transportation options, longer emergency response times, and constrained access routes.

Housing characteristics within the service area also contribute to vulnerability considerations. Many residential structures are located within wildland-urban interface (WUI) environments where wildfire exposure is elevated. Hazard events such as the Glass Fire have demonstrated the potential for large-scale residential displacement within the community. Such events illustrate the direct relationship between hazard impacts, housing stability, and utility service demand. Displaced residents may face financial hardship, insurance challenges, and prolonged reconstruction timelines, all of which influence water system operations and customer support policies.

Socioeconomic vulnerability may also be present within the service population. Households experiencing financial constraints may face difficulty absorbing rate adjustments, infrastructure repair costs, or conservation-related penalties during drought conditions. Because HMMWC operates as a mutual benefit corporation rather than a subsidized municipal utility, financial sustainability is closely tied to member contributions, rate structures, and system maintenance needs. Economic stressors associated with hazard events, including property damage or loss of income, can therefore affect both customers and system operations.

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Language access represents an additional component of population vulnerability. The Consumer Confidence Reports explicitly include notices requiring landlords to provide tenants with copies of the report and present critical water quality information in multiple non-English languages. This requirement reflects recognition that portions of the service population may have limited English proficiency. During emergency conditions, clear communication regarding water safety, conservation mandates, boil water notices, or service interruptions is essential. Language barriers may increase risk by delaying comprehension of protective actions or emergency instructions. (HMMWC, 2024) Institutional and community-dependent populations within the Angwin area further shape vulnerability dynamics. The presence of educational facilities, congregate housing, and community-serving institutions may concentrate individuals who are more sensitive to utility disruptions. Water service interruptions affecting such facilities may have cascading consequences, including sanitation challenges, reduced fire protection capability, and operational constraints. These interdependencies underscore the role of HMMWC as a critical lifeline provider supporting public health, safety, and community stability.

Income & Housing
Analysis of American Community Survey (ACS) data illustrates distinct geographic patterns in both median household income and poverty rates within the district, reflecting differences in housing stock, development history, and land use.

Income characteristics within the HMMWC service area suggest a generally higher median household income relative to many other rural regions. Figure 7-2 shows that large portions of the service boundary fall within the upper income ranges represented on the map. Higher median incomes may indicate increased household capacity to absorb certain hazard-related costs, including insurance premiums, property hardening measures, and infrastructure repair expenses. Communities with higher income levels may also demonstrate greater access to financial resources, lending mechanisms, and recovery assistance following disaster events.

However, elevated median income values do not eliminate vulnerability. Income distributions within small geographic areas can mask variability among households, including the presence of fixed-income residents, retirees, and individuals with limited financial flexibility. Even in comparatively higher-income communities, hazard events such as wildfire can produce significant uninsured or underinsured losses, particularly where rebuilding costs, code compliance upgrades, and insurance market constraints intersect.

Housing loss or damage may therefore impose substantial economic strain despite broader income indicators.

Figure 7-3 indicates that the overall proportion of residents living below the federal poverty threshold is relatively low across much of the HMMWC service area. Lower poverty rates are generally associated with reduced baseline socioeconomic vulnerability and increased adaptive capacity. Nevertheless, localized pockets of economic vulnerability may still exist, particularly within areas characterized by rental housing, multi-family units, or seasonal occupancy. Households experiencing financial constraints may face heightened challenges related to hazard preparedness, emergency response, and long-term recovery.

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The housing patterns within the HMMWC service area reflect the rural, residential nature of the community.

Figure 7-4 indicates that a substantial proportion of housing units within the service boundary are owneroccupied, with many census block groups exhibiting owner-occupancy rates at the upper end of the mapped range. This pattern is consistent with development characteristics typical of mountain and rural communities, where residential properties are more likely to be individually owned rather than rented. High owner-occupancy rates often correlate with longer-term residency, increased investment in property maintenance, and greater financial exposure to hazard-related damages.

Owner-occupied housing introduces distinct resilience considerations. Property owners typically bear the direct costs associated with structural retrofits, defensible space improvements, insurance coverage, and post-disaster repairs. In hazard-prone environments such as Howell Mountain, this ownership structure may increase financial vulnerability following wildfire, earthquake, or landslide events. Damage to residential structures may result in substantial economic losses for individual households, prolonged displacement, and complex recovery processes. Hazard events affecting housing stability therefore have cascading implications for both community resilience and utility service demand.

Housing and income characteristics within the Howell Mountain region are further shaped by the area’s wildland-urban interface setting. Residential structures are dispersed throughout heavily vegetated landscapes where wildfire exposure is elevated. Hazard events affecting housing stock, such as the Glass Fire, have demonstrated the potential for widespread structural losses and long-term displacement.

Rebuilding timelines, insurance availability, and construction costs collectively influence recovery trajectories and community stability.

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Figure 7-2: HMMWC Median Household Income Map
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Figure 7-3: HMMWC Poverty Status Map
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Figure 7-4: HMMWC Housing Occupancy Map
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Dependent & Disabled Populations
Analysis of American Community Survey (ACS) data shows distinct geographic patterns in the concentration of residents in dependent age groups, children and older adults, as well as elderly residents living with disabilities. These populations may require additional assistance before, during, and after emergency events, and their spatial distribution has direct implications for evacuation planning, emergency response, and recovery.

Demographic patterns within the HMMWC service area indicate the presence of populations that may experience elevated vulnerability during hazard events. Figure 7-5 illustrates the spatial distribution of residents typically classified as dependents, including individuals under the age of 18 and adults over the age of 65. Across much of the service boundary, the proportion of residents within these dependent age categories falls within the lower to moderate ranges represented on the map. This pattern is consistent with rural residential communities where household compositions often vary between families, working-age adults, and retirees.

Dependent populations represent an important consideration in hazard mitigation planning because they may require additional assistance during emergencies. Younger residents rely on caregivers for evacuation, sheltering, and access to essential services, while older adults may face mobility limitations, medical dependencies, or heightened sensitivity to service disruptions. In geographically constrained mountain environments, evacuation complexity, limited transportation options, and extended response times can amplify these challenges. Disruptions to potable water service, whether caused by wildfire, drought, seismic activity, or infrastructure damage, may therefore have disproportionate effects on dependent populations.

Figure 7-6 provides further insight into populations with potential access and functional needs. The map indicates that the percentage of elderly residents (65 years and older) living with a disability varies across the service area but generally falls within the lower ranges depicted. Even where disability prevalence is comparatively low, the presence of elderly individuals with mobility, sensory, or health-related limitations introduces specific resilience considerations. Hazard events that affect infrastructure, utilities, or transportation networks may significantly impact individuals who depend on medical equipment, caregiver support, or consistent access to water for health and sanitation purposes.

Disabled and elderly populations often experience heightened risk during disasters due to evacuation barriers, communication challenges, and increased dependence on lifeline utilities. In rural mountain settings such as Howell Mountain, these risks may be compounded by terrain-driven constraints, including steep driveways, limited roadway connectivity, and potential isolation during wildfire or severe weather events. Extended power outages or water service interruptions may further exacerbate health and safety concerns for individuals requiring climate control, hydration, hygiene, or medical care.

Water system reliability is particularly critical for these populations. Potable water supports not only basic consumption but also sanitation, temperature regulation, and medical needs. Interruptions to water delivery or water quality degradation may therefore produce cascading impacts affecting household health, safety, and habitability. Understanding the distribution and characteristics of dependent and disabled populations is essential for evaluating hazard consequences, prioritizing mitigation investments, and supporting equitable resilience outcomes.

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Figure 7-5: HMMWC Dependent Age Groups Map
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Figure 7-6: HMMWC Disabled Elderly Map
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Race, Ethnicity & Language
Demographic patterns within the HMMWC service area reflect the broader population characteristics of the Angwin and Howell Mountain region. The ACS Race and Ethnicity Predominance snapshot, Figure 7-7, indicates that much of the service boundary is classified within categories associated with White alone, not Hispanic or Latino populations. This distribution is generally consistent with development patterns typical of rural mountain communities, where housing density is low and residential land uses dominate. While the predominance mapping highlights the largest represented racial or ethnic group within each census geography, it does not imply homogeneity, as smaller but meaningful demographic diversity may still be present throughout the service area.

Race and ethnicity are important considerations in hazard mitigation planning because they are often correlated with variations in socioeconomic conditions, housing characteristics, language access, and access to resources. Even in areas where a single demographic category is predominant, underlying diversity may influence household-level vulnerability, risk perception, and recovery capacity. Demographic diversity may also affect communication strategies, emergency preparedness outreach, and the effectiveness of hazard-related notifications issued by the water company.

Figure 7-8 provides additional insight into communication and access considerations within the HMMWC service population. The map indicates that the proportion of residents who speak Spanish at home is generally low across most of the service boundary. This pattern suggests that English is the primary language used within the community. However, lower mapped percentages do not eliminate the presence of households with limited English proficiency. Even small language minority populations warrant consideration in hazard mitigation and emergency communication planning, particularly where protective actions, public health advisories, or water safety notifications are involved.

HMMWC’s regulatory communication practices recognize the importance of language accessibility. The Consumer Confidence Reports explicitly require landlords and property managers to distribute water quality information to tenants and include multilingual notices emphasizing the need to provide translated materials where appropriate. This framework acknowledges that portions of the service population may rely on languages other than English for critical information. During hazard events, including wildfire, drought emergencies, or water quality incidents, timely and understandable communication is essential for ensuring that all residents can take appropriate protective actions.

Language and cultural factors may influence hazard awareness, preparedness behaviors, and response actions. Households facing language barriers may experience delayed comprehension of emergency instructions, boil water advisories, or conservation mandates. These challenges may be particularly consequential in rapidly evolving events such as wildfires, where evacuation orders, service disruptions, and public safety information must be clearly conveyed. Even in communities with low overall language diversity, planning frameworks benefit from incorporating inclusive communication strategies.

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Figure 7-7: HMMWC Race and Ethnicity Map
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Figure 7-8: HMMWC Spanish-Speaking Households Map
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