PUBLIC DRAFT - JANUARY 2020 Mariposa County Local Hazard Mitigation Plan
©iStock.com/elgol (top), http://www.fotogestoeber.de (left) 2020 MARIPOSA COUNTY LOCAL HAZARD MITIGATION PLAN MARIPOSA COUNTY LOCAL HAZARD MITIGATION PLAN
TABLE OF CONTENTS 1.0 INTRODUCTION ...... 1-1 1.1 HAZARD MITIGATION PLANNING ...... 1-1 1.2 2020 LOCAL HAZARD MITIGATION PLAN SYNOPSIS ...... 1-1 2.0 PLANNING PROCESS ...... 2-1 2.1 OVERVIEW OF THE 2020 LHMP PLANNING PROCESS ...... 2-1 2.2 OPPORTUNITIES FOR STAKEHOLDERS ...... 2-3 2.3 PUBLIC INVOLVEMENT ...... 2-3 2.4 REVIEW AND INCORPORATION OF EXISTING PLANS AND REPORTS ...... 2-3 2.5 CONTINUED PUBLIC PARTICIPATION ...... 2-4 2.6 PLAN UPDATE METHOD AND SCHEDULE ...... 2-4 3.0 COMMUNITY PROFILE ...... 3-1 3.1 PLANNING AREA ...... 3-1 3.2 POPULATION AND DEVELOPMENT TRENDS ...... 3-3 3.3 CRITICAL FACILITIES ...... 3-3 4.0 HAZARD IDENTIFICATION AND RISK ASSESSMENT ...... 4-1 4.1 CLIMATE CHANGE...... 4-2 4.2 DROUGHT ...... 4-4 4.3 EARTHQUAKE ...... 4-6 4.4 FLOOD ...... 4-11 4.5 LANDSLIDE ...... 4-15 4.6 PUBLIC SAFETY POWER SHUTOFF ...... 4-19 4.7 WILDFIRE ...... 4-23 4.8 WINTER STORM ...... 4-31 5.0 MITIGATION STRATEGY ...... 5-1 5.1 AUTHORITIES, POLICIES, PROGRAMS, AND RESOURCES ...... 5-1 5.2 NATIONAL FLOOD INSURANCE PROGRAM PARTICIPATION ...... 5-7 5.3 MITIGATION GOALS ...... 5-7 5.4 RECOMMENDED IMPLEMENTATION MEASURES ...... 5-7 5.5 IMPLEMENTATION PLAN...... 5-11 5.6 PLAN INTEGRATION ...... 5-14 6.0 PLAN REVIEW, EVALUATION AND IMPLEMENTATION ...... 6-1 6.1 CHANGES IN DEVELOPMENT ...... 6-1 6.2 PROGRESS IN LOCAL MITIGATION EFFORTS ...... 6-1 6.3 CHANGES IN PRIORITIES ...... 6-2 7.0 PLAN ADOPTION ...... 7-3 7.1 FORMAL ADOPTION ...... 7-3
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LIST OF FIGURES Figure 3-1. Mariposa County ...... 3-2 Figure 3-2. Local Critical Facilities - Communication ...... 3-4 Figure 3-3. Local Critical Facilities - Community ...... 3-5 Figure 3-4. Local Critical Facilities - Education ...... 3-6 Figure 3-5. Local Critical Facilities - Emergency Response ...... 3-7 Figure 3-6. Local Critical Facilities - Mariposa County Government ...... 3-8 Figure 3-7. Local Critical Facilities - Health Services ...... 3-9 Figure 3-8. Local Critical Facilities - Historical Places & Districts ...... 3-10 Figure 3-9. Local Critical Facilities - Public Works & Utilities ...... 3-11 Figure 3-10. Local Critical Facilities - Transportation ...... 3-12 Figure 4-1. Historical Earthquakes (1769-2015) ...... 4-9 Figure 4-2. Seismic Hazard Areas ...... 4-10 Figure 4-3. Special Flood Hazard Areas ...... 4-14 Figure 4-4. Deep-Seated Landslide Susceptibility Areas ...... 4-18 Figure 4-5. CPUC Specific Fire Threat Areas ...... 4-22 Figure 4-6. Fire Hazard Severity Zones ...... 4-28 Figure 4-7. Fire Threat Areas ...... 4-29 Figure 4-8. Recent Wildfires (2000-2018) ...... 4-30 Figure 4-9. Winter Storm Snowfall (2018-2019) ...... 4-34
LIST OF TABLES Table 2-1. LHMP Timeline ...... 2-1 Table 2-2. Planning Committee ...... 2-2 Table 2-3. Existing Plans and Reports ...... 2-4 Table 2-4. Annual Review Tracker ...... 2-5 Table 3-1. Mariposa County Land Area ...... 3-1 Table 3-2. Local Critical Facilities ...... 3-3 Table 4-1. Climate Change Identification Profile ...... 4-2 Table 4-2. Climate Change Impact ...... 4-3 Table 4-3. Overall Summary of Vulnerability to Climate Change ...... 4-3 Table 4-4. Drought Identification Profile ...... 4-4 Table 4-5. Drought Impact ...... 4-5 Table 4-6. Overall Summary of Vulnerability to Drought ...... 4-5 Table 4-7. Earthquake Identification Profile ...... 4-6 Table 4-8. Earthquake Impact on Land Area ...... 4-7 Table 4-9. Earthquake Impact on County Critical Facilities ...... 4-8 Table 4-10. Overall Summary of Vulnerability to Earthquakes...... 4-8 Table 4-11. Flood Identification Profile ...... 4-11 Table 4-12. Flood Impact on Land Area ...... 4-12 Table 4-13. Flood Impact on Critical Facilities ...... 4-12 Table 4-14. Overall Summary of Vulnerability to Floods ...... 4-13
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MARIPOSA COUNTY LOCAL HAZARD MITIGATION PLAN
Table 4-15. Landslide Identification Profile ...... 4-15 Table 4-16. Landslide Impact on Land Area ...... 4-16 Table 4-17. Landslide Impact on Critical Facilities ...... 4-17 Table 4-18. Overall Summary of Vulnerability to Landslides ...... 4-17 Table 4-19. Public Safety Power Shutoff Identification Profile ...... 4-19 Table 4-20. Public Safety Power Shutoff Impact on Land Area...... 4-20 Table 4-21. Public Safety Power Shutoff Impact on Critical Facilities ...... 4-20 Table 4-22. Overall Summary of Vulnerability to Public Safety Power Shutoffs ...... 4-21 Table 4-23. Wildfire Identification Profile ...... 4-23 Table 4-24. Wildfire Impact on Land Area - Fire Hazard Severity Zones ...... 4-25 Table 4-25. Wildfire Impact on Land Area - Fire Threat Areas ...... 4-26 Table 4-26. Wildfire Impact on Critical Facilities - Fire Hazard Severity Zones ...... 4-26 Table 4-27. Wildfire Impact on Critical Facilities - Fire Threat Areas ...... 4-27 Table 4-28. Overall Summary of Vulnerability to Wildfires ...... 4-27 Table 4-29. Winter Storm Identification Profile ...... 4-31 Table 4-30. Annual Snowfall Impact on Land Area ...... 4-32 Table 4-31. Annual Snowfall Impact on Critical Facilities ...... 4-32 Table 4-32. Overall Summary of Vulnerability to Winter Storm ...... 4-33 Table 5-1 Human and Technical Resources for Hazard Mitigation ...... 5-2 Table 5-2. Financial Resources for Hazard Mitigation ...... 5-3 Table 5-3. Legal and Regulatory Resources for Hazard Mitigation ...... 5-6 Table 5-4. Recommended Implementation Measures ...... 5-8 Table 5-5. Prioritized Implementation Plan...... 5-12 Table 6-1. 2015 LHMP Implemented Mitigation Actions ...... 6-1
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MARIPOSA COUNTY LOCAL HAZARD MITIGATION PLAN
LIST OF ACRONYMS AND ABBREVIATIONS °F degrees Fahrenheit AECOM AECOM Technical Services, Inc. BRIC Building Resilient Infrastructure and Communities Cal FIRE California Department of Forestry and Fire Protection CFR Code of Federal Regulations CGS California Geological Survey
CO2 carbon dioxide CPAW Community Planning Assistance for Wildfires CPG Comprehensive Preparedness Guide CPUC California Public Utilities Commission CRS Community Rating System CCWPP Community Conservation Wildfire Protection Plans DHS Department of Homeland Security DMA Disaster Mitigation Act DR Disaster Declaration Number EPA Environmental Protection Agency EQ Earthquake FEMA Federal Emergency Management Agency FHSZ Fire Hazard Severity Zones FIRM Flood Insurance Rate Map FRAP Fire Resource and Assessment Program ft foot/feet GIS Geographic Information System IPCC Intergovernmental Panel on Climate Change LHMP Local Hazard Mitigation Plan LRA Local Responsibility Area M Magnitude NASA National Aeronautics and Space Administration NFIP National Flood Insurance Program OES Office of Emergency Services PGA Peak Ground Acceleration PG&E Pacific Gas & Electric RL Repetitive Loss
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MARIPOSA COUNTY LOCAL HAZARD MITIGATION PLAN
SFHA Special Flood Hazard Area SIZ Structure Ignition Zone SRA State Responsibility Area U.S. United States USACE United States Army Corps of Engineers USGS U.S. Geological Survey WUI wildland-urban interface
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1.0 INTRODUCTION
1.1 HAZARD MITIGATION PLANNING As defined in Title 44 of the Code of Federal Regulations (CFR), Subpart M, Section 206.401, hazard mitigation is “any action taken to reduce or eliminate the long-term risk to human life and property from natural hazards.” As such, hazard mitigation is any work to minimize the impacts of any type of hazard event before it occurs. Hazard mitigation aims to reduce losses from future disasters. It is a process that identifies and profiles hazards, analyzes the people and facilities at risk, and develops mitigation actions to reduce or eliminate hazard risk. The implementation of the mitigation actions, which include short- and long-term strategies that may involve planning, policy changes, programs, projects, and other activities, is the end result of this process. In recent years, local hazard mitigation planning has been driven by a federal law, known as the Disaster Mitigation Act of 2000 (DMA 2000). On October 30, 2000, Congress passed the DMA 2000 (Public Law 106-390), which amended the Robert T. Stafford Disaster Relief and Emergency Assistance Act of 1988 (Stafford Act) (Title 42 of the United States Code Section 5121 et seq.) by repealing the act’s previous mitigation planning section (409) and replacing it with a new mitigation planning section (322). This new section emphasized the need for state, tribal, and local entities to closely coordinate mitigation planning and implementation efforts. This new section also provided the legal basis for the Federal Emergency Management Agency’s (FEMA’s) mitigation plan requirements for the Hazard Mitigation Assistance grant programs.
1.2 2020 LOCAL HAZARD MITIGATION PLAN SYNOPSIS To meet the requirements of the DMA 2000, the Mariposa County Office of Emergency Services (OES) has prepared a Local Hazard Mitigation Plan (LHMP) (2020 LHMP in this plan) to assess risks posed by natural hazards and to develop a mitigation action plan for reducing the risks in Mariposa County. The 2020 LHMP replaces the LHMP, which was approved in 2015. The 2020 LHMP is organized to follow FEMA’s Local Mitigation Plan Review Tool, which demonstrates how local LHMPs meet the DMA 2000 regulations. As such, specific planning elements of this review tool are in their appropriate plan sections. The 2020 LHMP structure has been updated to including the following sections: • Section 2 Planning Process provides an overview of the 2020 planning process, starting with a plan update timeline. It identifies planning committee members and describes their involvement with the plan update process. It also details stakeholder outreach, public involvement and continued public involvement. It provides an overview of the existing plans and reports, details how those documents were incorporated into the 2020 LHMP, and lays out a plan update method and schedule. Supporting planning process documentation is listed in Appendix A. • Section 3 Community Profile describes the planning area for the 2020 LHMP. It touches on current population and development trends in the county. Finally, this section lists local critical facilities in Mariposa County. Supporting community profile information can be found in Appendix B. • Section 4 Hazard Identification and Risk Assessment describes each of the eight hazards addressed in this plan. Additionally, it includes impact (i.e., risk assessment) tables for land area and critical facilities and infrastructure in
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Mariposa County. An overall summary description is also provided for each hazard. Appendix C contains supporting risk assessment information. • Section 5 Mitigation Strategy details Mariposa County’s capabilities (authorities, policies, programs, and resources) available for hazard mitigation. It also describes the mitigation strategy, which is the blueprint for how hazard risks will be reduced. The mitigation strategy is made up of three main components: mitigation goal(s), potential mitigation actions and projects, and a prioritized mitigation action plan. • Section 6 Plan Review, Evaluation and Implementation discusses the revisions made to the 2020 LHMP to address changes in development, progress made in local mitigation efforts, and changes to priorities. • Section 7 Plan Adoption contains a scanned copy of the adoption resolution.
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2.0 PLANNING PROCESS
This section addresses Element A of the Local Mitigation Plan Regulation Checklist.
Regulation Checklist – 44 CFR 201.6 Local Mitigation Plans
Element A: Planning Process A1. Does the Plan document the planning process, including how it was prepared and who was involved in the process for each jurisdiction? (Requirement §201.6(c)(1)) A2. Does the Plan document an opportunity for neighboring communities, local and regional agencies involved in hazard mitigation activities, agencies that have the authority to regulate development as well as other interests to be involved in the planning process? (Requirement §201.6(b)(2)) A3. Does the Plan document how the public was involved in the planning process during the drafting stage? (Requirement §201.6(b)(1)) A4. Does the Plan describe the review and incorporation of existing plans, studies, reports, and technical information? (Requirement §201.6(b)(3)) A5. Is there discussion of how the community(ies) will continue public participation in the plan maintenance process? (Requirement §201.6(c)(4)(iii)) A6. Is there a description of the method and schedule for keeping the plan current (monitoring, evaluating and updating the mitigation plan within a 5‐year cycle)? (Requirement §201.6(c)(4)(i))
2.1 OVERVIEW OF THE 2020 LHMP PLANNING PROCESS The development of the 2020 LHMP was collaborative effort between Mariposa County OES, AECOM Technical Services, Inc. (AECOM), and a planning committee. Table 2-1 provides a timeline of the major plan update tasks and milestones by month over a 5-month period. Table 2- 2 lists the planning committee members and how they contributed to the development of the plan.
Table 2-1. LHMP Timeline
Date Tasks People Involved Reviewed the 2020 LHMP and decided to continue efforts to streamline the plan. LHMP project manager, September 2019 Determined the hazards to be profiled, including climate AECOM change, drought, earthquake, flood, landslide, public safety power shutoff, wildfire, and winter storm. Collected local and regional existing plans and reports. Determined the Geographic Information System (GIS) strategy for hazards and risk assessment. Identified initial list of stakeholders and emailed stakeholders. LHMP project manager, October 2019 AECOM, advisory Began developing/updating/collecting draft mitigation actions. committee Revised plan maintenance approach from quarterly meetings to annual review questionnaires. Conducted planning committee kick-off conference call.
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Table 2-1. LHMP Timeline
Date Tasks People Involved Crafted public outreach messages for the @mariposacountysheriff Facebook page and posted public outreach messages. Streamlined and updated the community profile section to only address the planning area, population and development trends and critical facilities. Created draft hazard figures. LHMP project manager, November 2019 Rewrote/updated the hazard profiles into a streamlined tabular AECOM, advisory format. committee Developed critical facilities risk assessment tables. Created draft risk assessment tables. Updated the capability assessment tables. Documented progress in local mitigation efforts. Addressed changes in development since the 2015 LHMP.
Developed a list of potential mitigation actions and prioritized LHMP project manager, December 2019 actions based on an updated prioritization approach. AECOM, advisory Created the Internal Draft LHMP. committee Created the Public Draft LHMP. LHMP project manager, Created Facebook post and emailed stakeholders about the January 2020 AECOM, advisory Public Draft LHMP. committee Created Final Draft LHMP.
Table 2-2. Planning Committee
Name Department/Agency/Title Contribution Served as the 2020 LHMP project manager, led Mariposa Count Sheriff’s planning committee conference call 1 and 2, and Alyssa Caroll Office/OES, Deputy Sheriff reviewed hazard figures and risk assessment tables, mitigation strategy, and Internal Draft LHMP. Mariposa Count Sheriff’s Participated in planning committee conference call 1 Doug Binnewies Office/OES, Sheriff-Coroner- and 2 and reviewed hazard figures, risk assessment Public Administrator tables, mitigation strategy, and Internal Draft LHMP. Participated in planning committee conference call 1 Mariposa County Planning Steve Engfer and 2 and reviewed hazard figures, risk assessment Department, Senior Planner tables, mitigation strategy, and Internal Draft LHMP. Participated in planning committee conference call 1 Mariposa County Public Works, Mike Healy and reviewed hazard figures, risk assessment Director tables, mitigation strategy, and Internal Draft LHMP. Participated in planning committee conference call 1 Mariposa County Sheriff’s and 2, reviewed hazard figures, risk assessment Kristie Mitchell Office/OES, Public Information tables, mitigation strategy, and Internal Draft LHMP, Officer and posted all public outreach information on Facebook. Participated in planning committee conference call 1 Mariposa County Planning Ben Ogren and 2 and reviewed hazard figures, risk assessment Department, Senior GIS Specialist tables, mitigation strategy, and Internal Draft LHMP.
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Table 2-2. Planning Committee
Name Department/Agency/Title Contribution Participated in planning committee conference call 1 Mariposa Count Sheriff’s Kevin Packard and 2 and reviewed hazard figures, risk assessment Office/OES, Sergeant tables, mitigation strategy, and Internal Draft LHMP. Participated in planning committee conference call 1 Mariposa County Administration, Molly Stephens and 2 and reviewed hazard figures, risk assessment Administrative Officer tables, mitigation strategy, and Internal Draft LHMP. Participated in planning committee conference call 1 Mariposa County Administration, Leigh Westerlund and 2 and reviewed hazard figures, risk assessment Assistant Administrative Officer tables, mitigation strategy, and Internal Draft LHMP.
2.2 OPPORTUNITIES FOR STAKEHOLDERS On November 1, 2019, the LHMP project manager reached out to stakeholders via email (Appendix A) about the 2020 LHMP and invited them to participate in the plan update process. Stakeholders included: neighboring counties (Tuolomne County, Madera County, Merced County, and Stanislaus County), local and regional partners (Mariposa County Unified School District, Mariposa Chamber of Commerce, American Red Cross Central California Region, and John C. Fremont Healthcare District), State partners (Cal OES, California Department of Transportation, California Department of Forestry and Fire Protection [Cal FIRE], and California Highway Patrol), and federal partners (National Park Service, Yosemite National Park). The LHMP project manager reached out to the stakeholders again on January 10, 2020, inviting them to review and provide comments about the Public Draft LHMP.
2.3 PUBLIC INVOLVEMENT The Mariposa County Sheriff’s Office engaged the public in the plan update process through social media. Information about the 2020 LHMP including plan kick-off, overview of hazard mitigation planning and the public draft plan were posted to the @mariposacountysheriff Facebook page in November and January. The LHMP project manager placed a copy of the public draft plan for public comment on the Mariposa County Sheriff’s Office website on January 10, 2020. Mariposa County Sheriff’s Office received a several likes and a few comments on the @mariposacountysheriff Facebook page. All public involvement documentation is located in Appendix A.
2.4 REVIEW AND INCORPORATION OF EXISTING PLANS AND REPORTS Table 2-3 lists the existing relevant plans and reports reviewed and incorporated into the 2020 LHMP.
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Table 2-3. Existing Plans and Reports
Plans and Reports Information to be Incorporated into the 2020 LHMP 2019 Mariposa County Community Summary of recommendations were into the 2020 LHMP’s mitigation Planning Assistance for Wildfires (CPAW) strategy. Threat assessment information was incorporated into the 2020 2019 Mariposa County Public Safety LHMP’s hazard identification section. Risk communication and public Power Shutoff Response Plan information was incorporated into the 2020 LHMP’s mitigation strategy. 2018 California’s Fourth Climate Change Summary of report was incorporated into the 2020 LHMP’s hazard Assessment – Sierra Nevada Region identification and risk assessment sections. Report 2017 County of Mariposa General Plan – Flood, landslide and wildfire implementation measures were Volume I, Safety Element (2017 Safety incorporated into the 2020 LHMP’s mitigation strategy. Element) 2014 Mariposa County Drought Background drought information incorporated into the 2020 LHMP’s Preparedness Plan hazard identification. 2014 Madera – Mariposa – Merced Pre-fire management projects were considered for the 2020 LHMP’s Strategic Fire Plan mitigation strategy. 2012 Mariposa County Community Proposed mitigation projects were considered for the 2020 LHMP’s Conservation Wildfire Protection Plan mitigation strategy. (CCWPP)
2.5 CONTINUED PUBLIC PARTICIPATION A copy of the 2020 LHMP will be available on the Mariposa County OES website along with contact information. The Mariposa County OES will notify residents (and seek input) of any changes or updates to the 2020 LHMP, including mitigation projects identified in the plan as they are implemented, and also announce the 2025 plan update kick-off via @mariposacountysheriff on Facebook.
2.6 PLAN UPDATE METHOD AND SCHEDULE The 2015 LHMP recommended annual reviews, meetings, and mitigation project progress report submittals over the lifespan of the 2015 LHMP. The annual review worksheets were not completed and it is unknown how often specific departments/agencies met to track the status of mitigation projects. Moving forward, annual reviews will be carried out by the LHMP project manager, with input from specific planning committee members as needed. The annual review will be similar to the process identified in the 2019 CPAW in that the review will be tracked in a table in this document (Table 2-4). FEMA-funded mitigation projects will continue to be tracked and reviewed using FEMA Mitigation Progress Report forms, and progress summaries will be included in Table 2-4. During 2024, the LHMP project manager will: complete the annual review tracker; reconvene the planning committee and update membership, if necessary; review Table 2-4; determine hazards to be included in the 2025 LHMP; develop a new work plan; and begin the plan update process.
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Table 2-4. Annual Review Tracker
New Relevant Mitigation Actions Public Outreach Changes Made to 2020 Year Disasters that Occurred Studies/Reports to Implemented Conducted LHMP Include in 2025 LHMP 2021 2022 2023 2024
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3.0 COMMUNITY PROFILE
3.1 PLANNING AREA For the purposes of this plan, the planning area boundaries are geographic and include all of Mariposa County. Mariposa County is located in central California, adjacent to the San Joaquin Valley in the central Sierra Nevada. It is surrounded by Tuolumne County to the north and east, Madera County to the south, and Merced and Stanislaus counties to the west. Mariposa County covers 1,463 square miles, roughly 48 percent of which is covered by national forest and park land; 19 percent of the county is covered by the Sierra National Forest and the Stanislaus National Forest, and 29 percent is covered by Yosemite National Park. Additionally, another 7.8 percent of the county’s land is managed by the U.S. Department of the Interior Bureau of Land Management. The remainder of the county is owned privately and consists of rangelands, chaparral fuel types, Oak lands, and pine forests. As shown in Table 3-1, the county is made up of 14 unincorporated communities that are recognized as census-designated places. According to the 2010 U.S. Census, approximately half of the county’s population lives in rural settings with the balance residing in and around various communities.
Table 3-1. Mariposa County Land Area
Community Square Miles Population (2010) Mariposa County 1,462.64 18,251 Bear Valley 7.24 125 Bootjack 7.06 960 Buck Meadows 1.74 31 Catheys Valley 23.46 825 Coulterville 4.22 201 El Portal 1.06 474 Fish Camp 0.91 59 Greeley Hills 21.09 915 Hornitos 1.17 75 Lake Don Pedro 12.57 1,077 Mariposa 3.04 2,173 Midpines 24.54 1,204 Wawoma 6.34 169 Yosemite Valley 2.12 1,035
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Buck Meadows 120
Greeley Hill Yosemite Valley 140
Coulterville 132
El Portal
140 49 Lake Don Pedro
M e r c e d C o u n t y 41
Bear Valley Midpines Wawona
Hornitos 49 Mariposa Fish Camp Bootjack
49 Catheys Valley Ma d e r a C o u n t y
140
0 2.5 5 10 Miles
Legend Census Designate Place (CDP) Mariposa County Figure 3-1 National Forest / Park Source 2019 Mariposa County Earthquake Shaking Potential for California (2016) https://maps.conservation.ca.gov Local Hazard Mitigation Plan
MARIPOSA COUNTY LOCAL HAZARD MITIGATION PLAN
3.2 POPULATION AND DEVELOPMENT TRENDS Using the most recent data available, the United States (U.S.) Census Bureau American Community Survey shows that the population in Mariposa County remained steady, only falling by 0.99 percent (i.e., 17,789 to 17,658) between 2015 and 2017. During the same 3-year reporting period, total housing units only increased by 1 percent, from 10,312 to 10,378. The County of Mariposa General Plan – Volume III notes that the county will likely continue to have limited development due to extensive areas of public land and steep terrain. For the 2020 LHMP, population and residential buildings are not included in the risk assessment. As 2020 U.S. Census tract data become available, this information may be included in future plan updates.
3.3 CRITICAL FACILITIES A critical facility provides services and functions essential to a community, especially during and after a disaster. Common types of critical facilities include: fire stations, police stations, hospitals, schools, water and waste water systems, and utilities. Critical facilities may also include places that can be used for sheltering or staging purposes, such as community centers and libraries. Critical facilities may also include large public gathering spots. Mariposa County does not currently maintain a centralized critical facilities database. For the 2020 LHMP, 130 county-owned and county-related critical facilities, as well as local, private critical facilities were collected from various county department and agencies. Critical facility names and addresses were then geocoded to a location and the resulting geographic features were used for the risk assessment. The results of this process are shown in Table 3-2 and Figure 3-2 through Figure 3-10. Facility-specific information is provided in Appendix B.
Table 3-2. Local Critical Facilities
Type of Critical Facility # of Facilities Communications 4 Community 33 Education 15 Emergency Response 23 Government 16 Health Services 5 Historic Places & Districts 7 Public Works & Utilities 20 Transportation 7
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Buck Meadows 120
Greeley Hill Yosemite Valley 140
Coulterville 132
El Portal
140 49 Lake Don Pedro
M e r c e d C o u n t y 41
Bear Valley Midpines Wawona
Hornitos 49
Mariposa Fish Camp Bootjack
49 Catheys Valley Ma d e r a C o u n t y
140
0 2.5 5 10 Miles
Legend Communication facility Local Critical Facilities - Communication Census Designate Place (CDP) Figure 3-2
National Forest / Park 2019 Mariposa County Source Mariposa County (2019) Local Hazard Mitigation Plan T u o l u m n e C o u n t y
Buck Meadows 120
Greeley Hill
Yosemite Valley 140
132 Coulterville
El Portal
140 49 Lake Don Pedro
M e r c e d C o u n t y 41
Bear Valley Midpines Wawona
Hornitos 49
Mariposa Fish Camp
Bootjack 49
Catheys Valley Ma d e r a C o u n t y
140
0 2.5 5 10 Miles
Legend Community facility Local Critical Facilities - Community Census Designate Place (CDP) Figure 3-3
National Forest / Park 2019 Mariposa County Source Mariposa County (2019) Local Hazard Mitigation Plan T u o l u m n e C o u n t y
Buck Meadows 120
Greeley Hill
Yosemite Valley 140
132 Coulterville
El Portal
140 49 Lake Don Pedro
M e r c e d C o u n t y 41
Bear Valley Midpines Wawona
Hornitos 49
Mariposa Fish Camp Bootjack
49 Catheys Valley Ma d e r a C o u n t y
140
0 2.5 5 10 Miles
Legend Education facility Local Critical Facilities - Education Census Designate Place (CDP) Figure 3-4
National Forest / Park 2019 Mariposa County Source Mariposa County (2019) Local Hazard Mitigation Plan T u o l u m n e C o u n t y
Buck Meadows 120
Greeley Hill
Yosemite Valley 140 Coulterville 132
El Portal
140 49 Lake Don Pedro
M e r c e d C o u n t y 41
Bear Valley Midpines Wawona
Hornitos 49 Fish Camp Mariposa Bootjack
49
Catheys Valley Ma d e r a C o u n t y
140
0 2.5 5 10 Miles
Legend Emergency response facility Local Critical Facilities - Emergency Response Census Designate Place (CDP) Figure 3-5
National Forest / Park 2019 Mariposa County Source Mariposa County (2019) Local Hazard Mitigation Plan T u o l u m n e C o u n t y
Buck Meadows 120
Greeley Hill Yosemite Valley 140
Coulterville 132
El Portal
140 49 Lake Don Pedro
M e r c e d C o u n t y 41
Bear Valley Midpines Wawona
Hornitos 49
Mariposa Fish Camp Bootjack
49 Catheys Valley Ma d e r a C o u n t y
140
0 2.5 5 10 Miles
Legend Mariposa County government facility Local Critical Facilities - Mariposa County Government Census Designate Place (CDP) Figure 3-6 National Forest / Park 2019 Mariposa County Source Mariposa County (2019) Local Hazard Mitigation Plan T u o l u m n e C o u n t y
Buck Meadows UV120
Greeley Hill (! Yosemite Valley UV140 Coulterville UV132
El Portal
140 49 UV Lake Don Pedro UV
M e r c e d C o u n t y UV41
Bear Valley Midpines Wawona (!
49 Hornitos UV (!(! Mariposa Fish Camp Bootjack
UV49 Catheys Valley Ma d e r a C o u n t y UV140 . 0 2.5 5 10 Miles
Legend (! Health facility Local Critical Facilities - Health Services Census Designate Place (CDP) Figure 3-7
National Forest / Park 2019 Mariposa County Source Mariposa County (2019) Local Hazard Mitigation Plan T u o l u m n e C o u n t y
Buck Meadows 120
Greeley Hill Yosemite Valley 140
132 Coulterville
El Portal
140 49 Lake Don Pedro
M e r c e d C o u n t y 41
Bear Valley Midpines Wawona
Hornitos 49
Mariposa Fish Camp Bootjack
49 Catheys Valley Ma d e r a C o u n t y
140
0 2.5 5 10 Miles
Legend Historic place & district Local Critical Facilities - Historic Places & Districts Census Designate Place (CDP) Figure 3-8
National Forest / Park 2019 Mariposa County Source Mariposa County (2019) Local Hazard Mitigation Plan T u o l u m n e C o u n t y
Buck Meadows 120
Greeley Hill Yosemite Valley 140 Coulterville 132
El Portal
140 49 Lake Don Pedro
M e r c e d C o u n t y 41
Bear Valley Midpines Wawona
Hornitos 49 Mariposa Fish Camp Bootjack
49 Catheys Valley Ma d e r a C o u n t y
140
0 2.5 5 10 Miles
Legend Public Works facility & utility Local Critical Facilities - Public Works & Utilities Census Designate Place (CDP) Figure 3-9 National Forest / Park 2019 Mariposa County Source Mariposa County (2019) Local Hazard Mitigation Plan T u o l u m n e C o u n t y
Buck Meadows 120
Greeley Hill Yosemite Valley 140
Coulterville 132
El Portal
140 49 Lake Don Pedro
M e r c e d C o u n t y 41
Bear Valley Midpines Wawona
Hornitos 49
Mariposa Fish Camp Bootjack
49 Ma d e r a C o u n t y Catheys Valley
140
0 2.5 5 10 Miles
Legend Transportation infrastructure Local Critical Facilities - Transportation Census Designate Place (CDP) Figure 3-10
National Forest / Park 2019 Mariposa County Source Mariposa County (2019) Local Hazard Mitigation Plan
MARIPOSA COUNTY LOCAL HAZARD MITIGATION PLAN
4.0 HAZARD IDENTIFICATION AND RISK ASSESSMENT
This section addresses Element B of the Local Mitigation Plan Regulation Checklist.
Regulation Checklist – 44 CFR 201.6 Local Mitigation Plans Element B: Hazard Identification and Risk Assessment
B1. Does the Plan include a description of the type, location, and extent of all natural hazards that can affect each jurisdiction(s)? (Requirement § 201.6(c)(2)(ii)) B2. Does the Plan include information on previous occurrences of hazard events and on the probability of future hazard events for each jurisdiction? (Requirement § 201.6(c)(2)(i)) B3. Is there a description of each identified hazard’s impact on the community as well as an overall summary of the community’s vulnerability for each jurisdiction? (Requirement §201.6(c)(2)(ii)) B4. Does the Plan address NFIP insured structures within the jurisdiction that have been repetitively damaged by floods? (Requirement §201.6(c)(2)(ii))
For the 2020 LHMP, the LHMP project manager and consultant revisited the hazards profiled in the 2015 LHMP. They determined that based on recent disaster declarations, climate change, drought, and public safety power shutoff should be included as hazards along with earthquake, flood, landslide, wildfire, and winter storm (which were included in the 2015 LHMP). Hazard identification consists of describing the nature of the hazard, disaster history, location, extent/severity, and probability of future events. Hazard identification profiles have been developed for each of the eight hazards addressed in Section 4.1 through Section 4.8. Additionally, semi-quantitative or qualitative impact tables as well as summary descriptions have been created for each hazard. The section does not address the National Flood Insurance Program’s (NFIP) repetitively damaged structures as the County does not participate in the NFIP. According to the Comprehensive Preparedness Guide (CPG) 201: Threat and Hazard Identification and Risk Assessment Guide—Second Edition (CPG 201) drought, earthquake, flood, landslide, and wildfire are classified natural hazards. CPG 201 does not classify climate change or public safety power shutoff. As such, the hazards profiled for this LHMP are discussed in alphabetical order and not by CPG 201 classification. The order does not signify level of risk.
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4.1 CLIMATE CHANGE
Table 4-1. Climate Change Identification Profile
Profile Description Climate change is defined as the average statistics of weather, which includes temperature, precipitation, and seasonal patterns in a particular region. Climate change refers to the long-term and irrevocable shift in these weather-related patterns, either regionally or globally. The Earth and its natural ecosystem are very closely tied to the climate and any permanent climate change will lead to an imbalance in the existing ecosystem, impacting the way people live, the food they grow, their health, the wildlife, the availability of water, and much more. Research indicates that much of this warming is due to human activities, primarily burning fossil fuels and clearing forests, that release carbon dioxide (CO2) and other gases into the atmosphere, trapping in heat that would otherwise escape into space. Once in the atmosphere, these heat-trapping emissions remain there for many years (for example, CO2 lasts about 100 years). If left unchecked, by the end of the Nature century, CO2 concentrations could reach levels three times higher than pre-industrial times. According to most climatologists, the planet is starting to experience shifts in climate patterns and increased frequency of extreme weather events at both the global and local levels. Over the next century, increasing atmospheric greenhouse gas concentrations are expected to cause a variety of changes to local climate conditions, including sea level rise and storm surge in coastal areas, reduced mountain snow pack, increased riverine flooding, and more frequent, higher temperatures (leading to extreme heat events and wildfires), particularly inland, decreasing air quality, and extended periods of drought. These effects of climate change are expected to negatively impact water and electricity demand and supplies in Mariposa County. Decreasing air quality and extreme heat days will degrade public health and increase wildfire risk. According to California’s Fourth Climate Change Assessment – Sierra Nevada Region Report, Location climate change is already underway in the Sierra Nevada, which includes all of Mariposa County. The history of the scientific discovery of climate change began in the early 19th century, when ice ages and other natural changes in paleoclimate were first suspected and the natural greenhouse effect first identified. In the late 19th century, scientists first argued that human emissions of greenhouse gases could change the climate. Many other theories of climate change were advanced, involving forces from volcanism to solar variation. In the 1960s, the warming effect of carbon dioxide gas became increasingly convincing, although some scientists also pointed out that human activities, in the form of atmospheric aerosols (e.g., "pollution"), could have cooling effects as well. During the 1970s, scientific opinion increasingly favored the warming viewpoint. By the 1990s, as a result of improving fidelity of computer models and observational work confirming the Milankovitch theory of the ice ages, a consensus position formed: greenhouse gases were deeply involved in most climate changes, and human emissions were bringing serious global warming. History Since the 1990s, scientific research on climate change has expanded and includes multiple disciplines, significantly increasing our understanding of causal relations, links with historic data, and ability to numerically model climate change. The most recent work has been summarized in the Assessment Reports by the Intergovernmental Panel on Climate Change (IPCC). Climate change is a significant and lasting change in the statistical distribution of weather patterns over periods ranging from decades to millions of years. It may be a change in average weather conditions, or in the distribution of weather around the average conditions (i.e., more or fewer extreme weather events). Climate change is caused by factors that include oceanic processes (such as oceanic circulation), biotic processes, variations in solar radiation received by Earth, plate tectonics and volcanic eruptions, and human-induced alterations of the natural world; these latter effects are currently causing global warming. "Climate change" is often used to describe human- specific impacts. Over the next century, scientists predict that temperatures in the Sierra Nevada, including Mariposa County, are projected to rise by 6 to 9 Fahrenheit (°F) on average, raising the “transition” Extent / from rain to snow by 1,500 to 3,000 feet (ft.). As a result of the projected warming, snowpack in the Severity Sierra Nevada will only be likely at 6,000 ft. in elevation or above, resulting in a loss of 60 percent of current snowpack. Future precipitation models for the region are less certain, but scientists expect precipitation extremes (deluge – drought) to increase with climate change.
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Table 4-1. Climate Change Identification Profile
Profile Description According to the National Aeronautics and Space Administration (NASA), “the current warming trend is of particular significance because most of it is extremely likely (i.e., greater than 95 percent Recurrence probability) to be the result of human activity since the mid-20th century and proceeding at a rate Probability that is unprecedented over decades to millennia.” NASA also states that “scientists have high confidence that global temperatures will continue to rise for decades to come, largely due to greenhouse gases produced by human activities.”
Table 4-2. Climate Change Impact
Climate Change Climate change impacts on the natural environment can include: increase in temperature with long-term warming trends; increase in extreme weather events including floods, drought and wildfire; decrease in snowpack; lower carbon storage; and a reduction in soil and vegetation moisture, which in turn affects rivers, lakes, and flora and fauna. Climate change impacts on the built environment can include: changes in the water cycle, Summary which will impact the water management system; stresses on local storm water and flood management systems; interruption of transportation and utilities; and increase in wildfire and flood threats to properties. Climate change impacts on human health can include: heat related illnesses and death, injuries, and fatalities due to severe weather; asthma and cardiovascular disease due to air pollution; and mental health impacts due to climate degradation.
Table 4-3. Overall Summary of Vulnerability to Climate Change
Climate Change All of Mariposa County is vulnerable to climate change. As outlined in Table 4-2, climate change is already occurring. According to scientists, larger changes are to come by the end of the century and will include a combination of warmer temperatures and greater Summary precipitation variability. These factors are expected to increase floods as well as droughts and affect the region’s fire regime, ecosystems and biodiversity, water resources, and communities.
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4.2 DROUGHT
Table 4-4. Drought Identification Profile
Profile Description Drought is a normal, recurrent feature of virtually all climatic zones, including areas of both high and low rainfall, although characteristics will vary significantly from one region to another. Drought differs from normal aridity, which is a permanent feature of the climate in areas of low rainfall. Drought is the result of a natural decline in the expected precipitation over an extended period of time, typically one or more seasons in length. Other climatic characteristics impact the severity of drought conditions, such as high temperature, high wind, and low relative humidity. Four common definitions for drought are provided as follows: • Meteorological drought is defined solely on the degree of dryness, expressed as a departure of actual precipitation from an expected average or normal amount based on monthly, seasonal, or annual time scales. • Hydrological drought is related to the effects of precipitation shortfalls on stream flows and reservoir, lake, and groundwater levels. • Agricultural drought is defined principally in terms of soil moisture deficiencies relative to Nature water demands of plant life, usually crops. • Socioeconomic drought associates the supply and demand of economic goods or services with elements of meteorological, hydrologic, and agricultural drought. Socioeconomic drought occurs when the demand for water exceeds the supply as a result of weather-related supply shortfall. It may also be referred to as a water management drought. A drought’s severity depends on numerous factors, including duration, intensity, and geographic extent, as well as regional water supply demands by humans and vegetation. Due to its multi- dimensional nature, drought is difficult to define in exact terms and poses difficulties in terms of comprehensive risk assessments. Drought differs from other natural hazards in three ways. First, the onset and end of a drought are difficult to determine due to the slow accumulation and lingering of effects of an event after its apparent end. Second, the lack of an exact and universally accepted definition adds to the confusion of its existence and severity. Third, in contrast with other natural hazards, the impact of drought is less obvious and may be spread over a larger geographic area. These characteristics have hindered the preparation of drought contingency or mitigation plans by many governments. The occurrence of drought is regional in nature and scope, which holds true for Mariposa County. Location Therefore, drought typically affects the entire county when it occurs. Drought is a cyclic part of the climate of California, occurring in both summer and winter, with an average recurrence interval between 3 and 10 years. Droughts in California over the past 100 years are listed below. The most recent drought from 2011 to 2015 was the driest 4-year period on record in California since recordkeeping began in 1895. • 1917-1921, Statewide except for central Sierra Nevada and north coast • 1922-1926, Statewide except for central Sierra Nevada • 1928-1937, Statewide History • 1943-1951, Statewide • 1959-1962, Statewide • 1976-1977, Statewide, except for southwestern deserts • 1987-1992, Statewide • 2007-2009, Statewide, particularly the central coast • 2011-2015, Statewide The National Drought Mitigation Center produces drought monitor maps for the United States. It classifies droughts into five categories: D0 is the least severe, with abnormally dry conditions; and Extent / D4 is the most severe, with exceptional drought conditions. California, including Mariposa County, Severity was in some form of drought for 376 consecutive weeks from December 20, 2011 until March 14, 2019. As of November 27, 2019, Mariposa County is listed as D0, abnormally dry.
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Table 4-4. Drought Identification Profile
Profile Description Researchers for California’s Fourth Climate Change Assessment have noted that California has a “highly variable climate” with wet or dry periods that can span years and are “heavily affected by Recurrence extreme precipitation events.” Furthermore, climate scientists also suggest the possibility of longer Probability and more destructive droughts with climate change. Therefore, drought conditions are likely to occur in Mariposa County every decade.
Table 4-5. Drought Impact
Drought Drought impacts on the natural environment can include decrease in snowpack and reduction in soil and vegetation moisture, which affects rivers, lakes, and flora and fauna. Drought impacts on the built environment can include changes in the water cycle, which Summary will impact the water management system and increase wildfire threats to properties. Drought impacts on human health can include heat related illnesses and death, asthma, and cardiovascular disease due to air pollution, and mental health impacts due to climate degradation.
Table 4-6. Overall Summary of Vulnerability to Drought Drought All of Mariposa County is vulnerable to drought. Drought conditions are likely to occur in Summary California at least every decade and can last several years. As noted in Table 4-5, drought could have vast economic, environmental, and social impacts on Mariposa County.
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4.3 EARTHQUAKE
Table 4-7. Earthquake Identification Profile
Profile Description An earthquake is a sudden motion or trembling caused by a release of strain accumulated in or along the edge of Earth’s tectonic plates. The effects of an earthquake can be felt far beyond the site of its occurrence. Earthquakes usually occur without warning and can cause massive damage and extensive casualties in a few seconds. Common effects of earthquakes are ground motion and shaking, surface fault ruptures, and ground failure. Ground motion is the vibration or shaking of the ground during an earthquake. When a fault ruptures, seismic waves radiate, causing the ground to vibrate. The severity of the vibration increases with the amount of energy released and decreases with distance from the causative fault or epicenter. Soft soils can amplify ground motions. In addition to ground motion, several secondary natural hazards can occur from earthquakes, such as the following: • Surface Faulting: Surface faulting is the differential movement of two sides of a fault at the Earth’s surface. Displacement along faults varies in terms of both length and width but can be significant (e.g., up to 20 feet), as can the length of the surface rupture (e.g., up to 200 miles). Surface faulting can cause severe damage to linear structures, including railways, highways, pipelines, tunnels, and dams. Nature • Liquefaction: Liquefaction occurs when seismic waves pass through saturated granular soil, distorting its granular structure, and causing some of the empty spaces between granules to collapse. Liquefaction causes lateral spreads (i.e., horizontal movements of commonly 10 to 15 feet, but up to 100 feet), flow failures (i.e., massive flows of soil, typically hundreds of feet, but up to 12 miles), and loss of bearing strength (i.e., soil deformations causing structures to settle or tip). Liquefaction can cause severe damage to property. • Landslides/Debris Flows: Landslides/debris flows occur as a result of horizontal seismic inertia forces induced in the slopes by the ground shaking. The most common earthquake- induced landslides include shallow, disrupted landslides such as rock falls, rockslides, and soil slides. Debris flows are created when surface soil on steep slopes becomes completely saturated with water. Once the soil liquefies, it loses the ability to hold together and can flow downhill at very high speeds, taking vegetation and/or structures with it. Slide risks increase after an earthquake during a wet winter. The two most common measures of earthquake intensity used in the United States are the Modified Mercalli Intensity Scale, which measures felt intensity, and peak ground acceleration (PGA), which measures instrumental intensity by quantifying how hard the earth shakes in a given location. Magnitude (M) is measured by the amplitude of the earthquake waves recorded on a seismograph using a logarithmic scale. There are there are two fault zones located in the western portion of Mariposa County, the Bear Mountain Fault and the Melones Fault; these compromise the Foothills Fault System, which is 223 miles long. Both fault zones were thought to be inactive until the Oroville Earthquake occurred in 1975 along the Bear Mountain Fault zone. Based on the Oroville Earthquake, and other geologic Location findings in the northern part of the system, the Foothills Fault System is considered active. Additionally, there are three other faults known to be active near Mariposa County: the San Andreas Fault to the west, the Owens Valley Fault to the east, and the White Wolf Fault to the south. According to the USGS, 54 earthquakes M 5.0> have been recorded in the region since 1769 (Figure 4-1). Four of these earthquakes have been larger than M 6.0 including: • M 6.8 on April 11, 1872 History • M 6.3 on April 10, 1881 • M 6.0 on September 30, 1889 • M 6.0 on May 6, 1910
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Table 4-7. Earthquake Identification Profile
Profile Description The strength of an earthquake’s ground movement can be measured by PGA. PGA measures the rate in change of motion relative to the established rate of acceleration due to gravity (i.e., 980 centimeters per second, per second). PGA is used to project the risk of damage from future earthquakes by showing earthquake ground motions that have a specified probability (e.g., 10%, 5%, or 2%) of being exceeded in 50 years. The ground motion values are used for reference in construction design for earthquake resistance and can also be used to assess relative hazard between sites when making economic and safety decisions. Extent / In 2008, the California Geological Survey (CGS) developed an updated map of earthquake Severity shaking potential for California. The map shows the relative intensity of ground shaking and damage in California from anticipated future earthquakes. Regions near major, active faults are shown in red and pink and experience stronger earthquake shaking more frequently. Regions that are distant from known, active faults are shown in orange and yellow and experience lower levels of shaking less frequently. Figure 4-2 indicates the level of low-frequency shaking potential in Mariposa County (where local soil conditions have greater effect on low frequency). In Mariposa County there are 132.51 (9.06%) square miles with strong low frequency shaking potential, and 67.64 square miles (4.62%) with severe low frequency shaking potential. In 2015, scientists developed a new earthquake forecast model for California. Known as the third Uniform California Earthquake Rupture Forecast, the model estimates the magnitude, location, Recurrence and likelihood of earthquake fault rupture throughout the state. The model shows that the Probability probability of having a nearby earthquake rupture of M 6.7 or greater in the next 30 years in Mariposa County is less than .10%, closer to .01% in most areas of the county.
Table 4-8. Earthquake Impact on Land Area
Violent EQ Shaking Extreme EQ Shaking Community # of Sq. Miles % of Sq. Miles # of Sq. Miles % of Sq. Miles Mariposa County 132.51 9.06 67.64 4.62 Bear Valley 0.39 5.36 0.00 0.00 Bootjack 0.00 0.00 0.00 0.00 Buck Meadows 0.00 0.00 0.00 0.00 Catheys Valley 0.00 0.00 0.00 0.00 Coulterville 0.00 0.00 0.00 0.00 El Portal 0.00 0.00 0.00 0.00 Fish Camp 0.00 0.00 0.00 0.00 Greeley Hills 0.00 0.00 0.00 0.00 Hornitos 0.00 0.00 0.00 0.00 Lake Don Pedro 0.00 0.00 0.00 0.00 Mariposa 0.00 0.00 0.00 0.00 Midpines 0.00 0.00 0.00 0.00 Wawoma 0.00 0.00 0.00 0.00 Yosemite Valley 0.00 0.00 2.06 97.21 EQ = earthquake
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Table 4-9. Earthquake Impact on County Critical Facilities
Strong EQ Shaking Severe EQ Shaking Facility Type # of Facilities % of Facilities # of Facilities % of Facilities Communications 0 0.00 0 0.00 Community 1 3.03 0 0.00 Education 0 0.00 2 13.33 Emergency 0 0.00 0 0.00 Response Government 1 6.25 0 0.00 Health Services 0 0.00 0 0.00 Historic Places & 0 0.00 0 0.00 Districts Public Works & 2 10.00 0 0.00 Utilities Transportation 0 0.00 1 14.29
EQ = earthquake
Table 4-10. Overall Summary of Vulnerability to Earthquakes
Drought Less than 15% of Mariposa County is vulnerable to strong and severe perceived shaking Mariposa County’s probability of experiencing a nearby earthquake rupture of M 6.7 or Summary greater in the next 30 years is less than .10%, and closer to .01% in most areas of the county. Should this type of earthquake occur, the northeastern portion of the county, which includes Yosemite Valley, is likely to experience light to moderate/heavy damage.
2020 PAGE | 4-8 Alpine
Sacramento Amador
Calaveras
Tuolumne
San Joaquin Mono
Stanislaus
Inyo Madera Merced
SantaLegend Clara Earthquakes M 5.0 > 6 - 7 5 - 6 Fresno 0 2.5 5 10 15 20 25 Miles Quaternary and Younger Faults Inferred Moderately Constrained Historical Earthquakes (1769-2015) Well Constrained Figure 4-1 San Benito Source Historic Earthquakes, 1769 to 2015 - 2019 Mariposa CountyTulare California (Magnitude 5.0-plus) (2019) Local Hazard Mitigation Plan Montereyhttps://maps.conservation.ca.gov T u o l u m n e C o u n t y
Buck Meadows 120
Greeley Hill Yosemite Valley 140
Coulterville 132
El Portal
140 49 Lake Don Pedro
M e r c e d C o u n t y 41
Bear Valley Midpines Wawona
Hornitos 49 Mariposa Fish Camp Bootjack
49 Catheys Valley Ma d e r a C o u n t y
140 Legend Census Designate Place (CDP)
National Forest / Park
Peak Ground Acceleration expressed 0 2.5 5 10 Miles in % g (gravity) for 2% probability of exceedance in 50 years Moderate (0.15) Seismic Hazard Areas Strong (0.25) Figure 4-2 Severe (0.35) Source 2019 Mariposa County Earthquake Shaking Potential for California (2016) https://maps.conservation.ca.gov Local Hazard Mitigation Plan
MARIPOSA COUNTY LOCAL HAZARD MITIGATION PLAN
4.4 FLOOD
Table 4-11. Flood Identification Profile
Profile Description A flood occurs when the existing channel of a stream, river, canyon, or other watercourse cannot contain excess runoff from rainfall or snowmelt, resulting in overflow onto adjacent lands. In coastal areas, flooding may occur when high winds or tides result in a surge of seawater into areas that are above the normal high tide line. Secondary hazards from floods can include: • Erosion or scouring of stream banks, roadway embankments, foundations, footings for bridge piers, and other features. Nature • Impact damage to structures, roads, bridges, culverts, and other features from high-velocity flow and from debris carried by floodwaters. Such debris may also accumulate on bridge piers and in culverts, increasing loads on these features or causing overtopping or backwater effects. • Destruction of crops, erosion of topsoil, and deposition of debris and sediment on croplands. • Release of sewage and hazardous or toxic materials when wastewater treatment plants are inundated, storage tanks are damaged, and pipelines are severed. In Mariposa County, two types of flooding occur: riverine flooding (also known as overbank flooding) and localized flooding. Riverine floodplains range from narrow, confined channels in the steep valleys of mountainous and hilly regions to wide, flat areas in plains and coastal regions. The amount of water in the floodplain is a function of the size and topography of the contributing watershed, the regional and local climate, and land use characteristics. Flooding in steep, mountainous areas is usually confined, strikes with less warning time, and has a short duration. Larger rivers typically have longer, more predictable flooding sequences and broad floodplains. FEMA has identified four riverine flooding Location sources in Mariposa County, including: Mariposa Creek, Mariposa River, Merced River – Left Overbank, and the South Fork Merced River. Areas prone to riverine flooding are shown in Figure 4-3. Localized flooding may also occur outside of recognized drainage channels or delineated floodplains due to a combination of locally heavy precipitation, increased surface runoff, and inadequate facilities for drainage and storm water conveyance. Such events frequently occur in flat areas and in urbanized areas with large impermeable surfaces, including Coulterville, El Portal, Hornitos, Mariposa, and Wawona. According to the NOAA Storm Events Database, there have been 25 days of flood events and 5 days of flash flooding events in Mariposa County over the past decade. Of these, the federal History government declared two flooding emergencies for Mariposa County, including: • DR-1952, December 17, 2010 – January 4, 2011 • DR-4308, February 1, 2017 – April 1, 2017 The magnitude of flooding that is used as the standard for floodplain management in the United States is a flood with a probability of occurrence of 1% in any given year. This flood is also known Extent / as the 100-year flood (i.e., base flood) and is considered a Special Flood Hazard Area (SFHA) and Severity identified on FEMA’s Flood Insurance Rate Maps (FIRM). The Mariposa County FIRM (Figure 4-3) identifies 27.39 square miles (1.87%) with a 1% annual chance of flooding. Floods can occur at any time but are most common with winter storms packed with subtropical Recurrence moisture. Based on previous occurrences, flood conditions are likely to occur in Mariposa County Probability 2-3 days each year.
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Table 4-12. Flood Impact on Land Area
1% Annual Chance of Flooding Community # of Sq. Miles % of Sq. Miles Mariposa County 27.39 1.87 Bear Valley 0.01 0.08 Bootjack 0.13 1.81 Buck Meadows 0.00 0.00 Catheys Valley 0.00 0.00 Coulterville 0.19 4.53 El Portal 0.21 20.18 Fish Camp 0.00 0.00 Greeley Hills 0.36 1.69 Hornitos 0.04 3.68 Lake Don Pedro 0.13 1.02 Mariposa 0.05 1.51 Midpines 0.00 0.00 Wawoma 0.22 3.43 Yosemite Valley 0.61 28.89
Table 4-13. Flood Impact on Critical Facilities
1% Annual Chance of Flooding Community # of Facilities % of Facilities Communications 0 0.00 Community 0 0.00 Education 0 0.00 Emergency Response 1 4.35 Government 0 0.00 Health Services 0 0.00 Historic Places & Districts 1 14.29 Public Works & Utilities 1 5.00 Transportation 2 28.57
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MARIPOSA COUNTY LOCAL HAZARD MITIGATION PLAN
Table 4-14. Overall Summary of Vulnerability to Floods
Flood Mariposa County is vulnerable to two types of flooding: riverine flooding (also known as overbank flooding) and localized flooding. Both types of flooding are a result of prolonged or intense rainfall that are usually associated with winter storms. In the County, there are 27.39 square miles (1.87%) with a 1% annual chance of flooding. These areas are known as the SFHA and include the Mariposa Creek, Mariposa River, Summary Merced River – Left Overbank, and the South Fork Merced River. Areas prone to localized flooding tend to be flat urbanized areas with large impermeable surfaces such as the towns of Mariposa, El Portal, Coulterville, Wawona, and Hornitos. Floods can block roadways and cause erosion, mudflows, debris flows, and water damage to structures, and result in land loss, injury, and even death.
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Buck Meadows 120
Greeley Hill Yosemite Valley 140
Coulterville 132
El Portal
140 49 Lake Don Pedro
M e r c e d C o u n t y 41
Bear Valley Midpines Wawona
Hornitos 49 Mariposa Fish Camp Bootjack
49 Catheys Valley Ma d e r a C o u n t y
140
0 2.5 5 10 Miles Legend Census Designate Place (CDP)
National Forest / Park Special Flood Hazard Areas 1% Annual Chance Flood Figure 4-3
Source FEMA Digital Flood Insurance Rate Map 2019 Mariposa County (2016, 2018) https://msc.fema.gov/ Local Hazard Mitigation Plan
MARIPOSA COUNTY LOCAL HAZARD MITIGATION PLAN
4.5 LANDSLIDE
Table 4-15. Landslide Identification Profile
Profile Description Landslide is a general term for the dislodging and fall of a mass of soil or rocks along a sloped surface, or for the dislodged mass itself. The term is used for varying phenomena, including mudflows, mudslides, debris flows, rock falls, rockslides, debris avalanches, debris slides, and slump-earth flows. Landslides may result from a wide range of combinations of natural rock, soil, or artificial fill. The susceptibility of hillside and mountainous areas to landslides depends on variations in geology, topography, vegetation, and weather. Landslides may also occur because of indiscriminate development of sloping ground or the creation of cut-and-fill slopes in areas of unstable or inadequately stable geologic conditions. Additionally, landslides often occur together with other natural hazards, thereby exacerbating conditions, as described below: Nature • Shaking due to earthquakes can trigger events ranging from rock falls and topples to massive slides. • Intense or prolonged precipitation that causes flooding can also saturate slopes and cause failures leading to landslides. • Wildfires can remove vegetation from hillsides, significantly increasing runoff and landslide potential. • Landslides into a reservoir can indirectly compromise dam safety or impact the dam itself. • Another type of landslide occurs in areas cut by perennial streams. As floodwaters erode channel banks, rivers have undercut clay-rich sedimentary rocks along their south bank, which destabilizes the ground and causes the ground above it to slide. In 2011, CGS created a deep-seated landslide grip map to show the relative likelihood of deep landslides in California. The map combines landslide inventory, geology, rock strength, slope, average annual rainfall and earthquake shaking potential layers to create classes of landslide Location susceptibility. The map shows areas of low landslide susceptibility, mainly the western portion of the county (Figure 4-4). However, the mountainous areas in the eastern portion of the county, along the Merced River Canyon and the Yosemite Valley, reach the high landslide susceptibility range. Historically, landslides/mudslides have occurred in the Merced River drainage or along the central southwest areas of the county. The costliest slide, known as the Ferguson Landslide, started in April 2006 and remains an active landslide today. This initial event completely buried State Route History 140 blocking the primary entrance to Yosemite National Park. A State of Emergency was declared for Mariposa County by June 2006. More recently, heavy storms in November 2018 caused several mudslides in the 2018 Ferguson Fire burn scar area. The extent or size of a landslide varies on the proportion of and type of material it carries, the geology of the area, and the initial cause of the slide. In general, rainfall-initiated landslides tend to be smaller (usually 100 to 5,000 cubic yards) than those triggered by earthquakes. The hazard potential is greatest in areas with steep slopes and certain geologic and soil conditions, such as expansive soils (i.e., clay soils that expand when wet). Deep-seated landslides are hundreds to thousands of feet in length or width and only move Extent / fractions of an inch per year. However, during heavy rainfall events, a landslide can move several Severity yards a minute or faster. In these areas, rocks have been weakened through faulting and fracturing, uplift, and saturated soils due to heavy or prolonged rainfall. Additionally, these slippages can be exasperated by the temperature fluctuation, known as the freeze-thaw cycle. Figure 4-4 shows the extent of deep-seated landslide susceptibility areas in Mariposa County. According to Figure 4-4, there are 41.21 square miles (2.82%) of land in Mariposa County located in Classes IX and X.
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Table 4-15. Landslide Identification Profile
Profile Description Shallow landslides can occur at any time during the winter but are more likely happen when the ground is nearly saturated, which typically occurs after the first few storms in November and December. However, deep-seated landslides generally need deep infiltration of rainfall (which can Recurrence take weeks or months to occur) to be triggered and therefore generally occur toward the end of Probability winter season. Every landslide event reported in Mariposa County has followed a winter storm/rain event; therefore, it is assumed that probability of a future landslide event will be highly tied to winter storm/rain events. Based upon historical occurrences, winter storm conditions are likely to occur in Mariposa County about 5 to 6 days each year.
Table 4-16. Landslide Impact on Land Area
Deep Seated Landslide Class IX and X Community # of Sq. Miles % of Sq. Miles Mariposa County 41.21 2.82 Bear Valley 0.30 4.13 Bootjack 0.00 0.00 Buck Meadows 0.00 0.00 Catheys Valley 0.00 0.00 Coulterville 0.00 0.00 El Portal 0.00 0.00 Fish Camp 0.00 0.00 Greeley Hills 0.00 0.00 Hornitos 0.00 0.00 Lake Don Pedro 0.00 0.00 Mariposa 0.00 0.00 Midpines 0.00 0.00 Wawoma 0.00 0.00 Yosemite Valley 0.42 19.60
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Table 4-17. Landslide Impact on Critical Facilities
Deep Seated Landslide Class IX and X Community # of Facilities % of Facilities Communications 0 0.00 Community 0 0.00 Education 0 0.00 Emergency Response 0 0.00 Government 0 0.00 Health Services 0 0.00 Historic Places & Districts 0 0.00 Public Works & Utilities 0 0.00 Transportation 0 0.00
Table 4-18. Overall Summary of Vulnerability to Landslides
Landslide Mariposa County is vulnerable to both shallow and deep-seated landslides. Both types of landslides are the result of ground saturation associated with winter storms. In the county, there are 41.21 square miles (2.82%) mapped as high-landslide susceptibility. The majority of these landslide-prone areas include the mountainous areas Summary of the county. However, landslides can occur along existing old landslides, at the base of slopes, the base of minor drainage hollows, the base or top of an old fill slope, the base or top of a steep cut slope, and developed hillsides where leach field septic systems are used. Landslides can block roadways and cause erosion, mudflows, and debris flows, damage to structures, and result in land loss, injury, and even death.
2020 PAGE | 4-17 T u o l u m n e C o u n t y
Buck Meadows UV120
Greeley Hill Yosemite Valley UV120 UV140 Coulterville UV132
El Portal
140 49 UV Lake Don Pedro UV
UV41
Bear Valley Midpines Wawona
Hornitos UV49 Mariposa Fish Camp Bootjack
UV49 Catheys Valley Ma d e r a C o u n t y
M e r c e d C o u n t y UV140 . 0 2.5 5 10 Miles
Census Designate Place (CDP) Deep-Seated Landslide Susceptibility Areas National Forest / Park Figure 4-4
Source Susceptibility to Deep-Seated 2019 Mariposa County Landslides in California (2018) https://maps.conservation.ca.gov Local Hazard Mitigation Plan
MARIPOSA COUNTY LOCAL HAZARD MITIGATION PLAN
4.6 PUBLIC SAFETY POWER SHUTOFF
Table 4-19. Public Safety Power Shutoff Identification Profile
Profile Description The risk of wildfire increases when several factors combine—these include high temperatures, high sustained, and peak winds, as well as critically low humidity. During these conditions, electrical transmission and distribution lines may ignite fires if they are downed by winds and/or trees. To reduce the chance of accidental fire ignition in certain areas, Pacific Gas & Electric (PG&E) may de-energize electrical grids or blocks off an area(s) in advance of or during periods of heightened risk conditions. Heightened risk conditions include: • Red Flag Warning declared by the National Weather Service. • Low humidity levels, generally 20% and below. • Forecasted sustained winds above approximately 25 miles per hour and wind gusts in excess Nature of approximately 45 miles per hour. • Site-specific conditions such as temperature, terrain, and local climate. • Condition of dry fuel on the ground and live vegetation (moisture content). • On-the-ground, real-time wildfire relation information from PG&E Wildfire Safety Operations Center and field observations from PG&E field crews. Per the California Public Utilities Commission (CPUC), utilities will only de-energize if the utility ”reasonably believes that there is an ‘imminent and significant risk’ to strong winds that may topple power lines or cause major vegetation-related damage to power lines, leading to increased risk of fire.” In 2012, the CPUC developed a statewide map to identify areas associated with increased risk for “utility associated wildfires.” The map, known as the CPUC Fire-Threat map, incorporates historical powerline wildfires and ranks fire-threat areas based on the risk that utility wildfires pose to people. Location Figure 4-5 shows the Tier 2 – Elevated and Tier 3 – Extreme CPUC Fire-Threat Areas in Mariposa County. Every town expect Hornitos includes Tier 2- Elevated Fire Threat Areas and the towns of Bootjack, Fish Camp, Greeley Hills, Mariposa, Midpines, and Wawoma compromises Tier 3 – Extreme Fire Threat Areas. Mariposa County recently experienced a public safety power shutoff on October 26, 2019. PG&E History de-energized the northern portions of the county over a 2-day period during Red Flag Warnings. As shown in Figure 4-5, 1008.01 square miles (68.92%) of Mariposa County are located in Tier 2 Extent / – Elevated CPUC Fire-Threat Ares with an additional 126.68 square miles (8.66%) located in Tier Severity 3 – Very High CPUC Fire-Threat Areas. PG&E “anticipates that a public safety power shutoff could occur 1 to 2 times a year in PG&E’s Recurrence service area, although it is impossible to predict future weather conditions in the new normal of Probability climate-driven extreme weather events.”
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MARIPOSA COUNTY LOCAL HAZARD MITIGATION PLAN
Table 4-20. Public Safety Power Shutoff Impact on Land Area
CPUC – Fire Threat Tier 2 CPUC – Fire Threat Tier 3
Elevated Areas Extreme Areas Community # of Sq. Miles % of Sq. Miles # of Sq. Miles % of Sq. Miles Mariposa County 1008.08 68.92 126.68 8.66 Bear Valley 7.24 99.99 0.00 0.00 Bootjack 6.62 93.71 0.44 6.29 Buck Meadows 1.74 100.00 0.00 0.00 Catheys Valley 14.67 62.54 0.00 0.00 Coulterville 4.22 99.99 0.00 0.00 El Portal 1.06 100.00 0.00 0.00 Fish Camp 0.02 1.78 0.89 98.22 Greeley Hills 15.14 71.76 5.96 28.24 Hornitos 0.00 0.00 0.00 0.00 Lake Don Pedro 12.29 97.77 0.00 0.00 Mariposa 1.91 62.89 0.39 12.81 Midpines 15.70 63.99 8.84 36.01 Wawoma 5.35 84.29 1.00 15.71 Yosemite Valley 2.12 99.99 0.00 0.00
Table 4-21. Public Safety Power Shutoff Impact on Critical Facilities
CPUC – Fire Threat Tier 2 CPUC – Fire Threat Tier 3
Elevated Areas Extreme Areas Facility Type # of Facilities % of Facilities # of Facilities % of Facilities Communications 2 50.00 0 0.00 Community 21 63.64 1 3.03 Education 10 66.67 0 0.00 Emergency 12 52.17 4 17.39 Response Government 5 31.25 1 6.25 Health Services 2 40.00 0 0.00 Historic Places & 3 42.86 0 0.00 Districts Public Works & 13 65.00 4 65.00 Utilities Transportation 5 71.42 0 0.00
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MARIPOSA COUNTY LOCAL HAZARD MITIGATION PLAN
Table 4-22. Overall Summary of Vulnerability to Public Safety Power Shutoffs
Public Safety Power Shutoffs All of Mariposa County is vulnerable to public safety power shutoffs, particularly during Red Flag Warnings. De-energization of electrical systems in affected areas can pose a life- safety risk to residents and impact other infrastructure systems. De-energization can also Summary impact the capabilities of local agencies to respond to wildfire due to loss of alert, warning, and public information communications systems including internet and cellular towers, inability to monitor or maintain water supplies, and a loss of traffic control systems that could support evacuation.
2020 PAGE | 4-21 T u o l u m n e C o u n t y
Buck Meadows 120
Greeley Hill Yosemite Valley 140
Coulterville 132
El Portal
140 49 Lake Don Pedro
M e r c e d C o u n t y 41
Bear Valley Midpines Wawona
Hornitos 49 Mariposa Fish Camp Bootjack
49 Catheys Valley Ma d e r a C o u n t y
140
Legend Census Designate Place (CDP) 0 2.5 5 10 Miles National Forest / Park
Tier 2 - Elevated CPUC Specific Fire Threat Areas Tier 3 - Extreme Figure 4-5 Source California Public Utilities Commission 2019 Mariposa County Fire Threat (2018) ftp://ftp.cpuc.ca.gov Local Hazard Mitigation Plan
MARIPOSA COUNTY LOCAL HAZARD MITIGATION PLAN
4.7 WILDFIRE
Table 4-23. Wildfire Identification Profile
Profile Description Wildfires spread by consuming flammable vegetation. This type of fire often begins unnoticed, spreads quickly, and is usually signaled by dense smoke that may be visible from miles away. Wildfires can be caused by human activities (e.g., unattended burns, campfires, or off-road vehicles without spark-arresting mufflers) or by natural events such as lightning. Wildfires often occur in forests or other highly vegetated areas. In addition, wildfires can be classified as forest, urban, interface or intermix fires, and prescribed burns. The following three factors contribute significantly to wildfire behavior and can be used to identify wildfire hazard areas: • Topography describes slope increases, which influences wildfire spread rate increases. South-facing slopes are also subject to more solar radiation, making them drier and thereby intensifying wildfire behavior. However, ridge tops may mark the end of wildfire spread because fire spreads more slowly (or may even be unable to spread) downhill. • Fuel is the type and condition of vegetation that plays a significant role in wildfire spread occurrence. Certain plant types are more susceptible to burning or will burn with greater intensity. Dense or overgrown vegetation increases the amount of combustible material available as fire fuel (referred to as the “fuel load”). The living-to-dead plant matter ratio is also important. Certain climate changes may increase wildfire risk significantly during prolonged Nature drought periods, as both living and dead plant matter moisture content decreases. Both the horizontal and vertical fuel load continuity is also an important factor. • Weather is the most variable factor affecting wildfire behavior. Temperature, humidity, wind, and lightning can affect ignition opportunities and fire spread rate. Extreme weather, such as high temperatures and low humidity, can lead to extreme wildfire activity. Climate change increases fire to vegetation ignition susceptibility due to longer dry seasons. By contrast, cooling and higher humidity often signal reduced wildfire occurrence and easier containment. Wildfire frequency and severity sometimes result from other hazard impacts such as lightning, drought, and infestations (e.g., damage caused by spruce-bark beetle infestations). If not promptly controlled, wildfires may grow into an emergency or disaster. Even small fires can threaten lives and resources and destroy improved properties. In addition to affecting people, wildfires may severely affect livestock and pets. Such events may require emergency water/food, evacuation, and shelter. Indirect wildfire effects can be catastrophic. In addition to stripping the land of vegetation and destroying forest resources, large, intense fires can harm the soil, waterways, and the land itself. Soil exposed to intense heat may lose its capability to absorb moisture and support life. Exposed soils erode quickly and exacerbate river and stream siltation; thereby increasing flood potential, harming aquatic life, and degrading water quality. Vegetation-stripped lands are more susceptible to increased debris flow hazards. The California Department of Forestry and Fire Protection’s (Cal FIRE) Fire Resource nd Assessment Program (FRAP) provides vital data on California's forests and rangelands through a variety of mapping tools. FRAP’s Fire Hazard Severity Zone (FHSZ) maps fire hazards based on factors such as fuel, terrain and weather. The FHSZ areas are represented as Moderate, High, and Very High. The maps are divided into local responsibility areas (LRAs) and state responsibility areas (SRAs). LRAs generally include cities, cultivated agriculture lands, and portions of the desert. LRA fire Location protection is typically provided by city fire departments, fire protection districts, counties, and by Cal FIRE under contract to the local government. SRA is a legal term defining the area where the state has financial responsibility for wildfire protection. Figure 4-6 displays the areas of Mariposa County most susceptible to wildfires. High FHSZs include Bear Valley, Catheys Valley, Coulterville, Lake Don Pedro, Mariposa, and Midpines. Very High FHSZs include Bear Valley, Buck Meadows, Coulterville, Fish Camp, Greeley Hills, and Midpines.
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MARIPOSA COUNTY LOCAL HAZARD MITIGATION PLAN
Table 4-23. Wildfire Identification Profile
Profile Description FRAP’s Fire Threat Area maps rates wildland fire threat based on the combination of potential fire behavior (fuel rank) and expected fire frequency (fire rotation). The threat areas are represented as low, moderate, high, very high, and extreme. As shown in Figure 4-7, every town in Mariposa County is located in the Very High fire threat area. In addition, Bear Valley, Boot Jack, Hornitos and Lake Don Pedro are located in the Extreme fire threat areas. As shown in Figure 4-8, wildfires are a common occurrence in Mariposa County Some of the county’s most destructive fires have occurred from 2000 to 2018 including: • The Ferguson Fire, which was caused by superheated fragments of a vehicle's catalytic converter and burned 96,901 acres in the Sierra National Forest, Stanislaus National Forest and Yosemite National Park over a 5-week period from July 13, 2018 to August 19, 2018. Two firefighters were killed, 19 firefighters were injured, and 10 structures were destroyed. • The Railroad Fire, which started August 29, 2017, burned 12,407 acres between the towns of Sugar Pine and Fish Camp in the Sierra National Forest. It was contained on October 24, 2017. The cause of the fire is unknown. • The Detwiler Fire was caused by a firearm on July 16, 2017 and burned 81,826 acres east and south of Lake McClure. By the time it was contained 5 weeks later, it had destroyed 131 History structures. • The Rim Fire was caused by an illegal camp fire and burned 255,858 acres in the Stanislaus National Forest from August 17, 2013 to October 24, 2013. It destroyed 11 homes and an additional 100 buildings and outbuildings. • The Telegraph Fire was caused by target shooting and burned 34,091 acres. It was started on July 25, 2008 and was contained on August 1, 2008. The fire destroyed 30 homes. • The Creek Fire near Yosemite National Park burned over 11,000 acres over a 1-week period from August 18, 2001 to August 24, 2001. During the drafting of this plan, the Briceburg Fire started in the Merced Canyon on October 6, 2019. It burned 5,563 acres before being fully contained on October 23, 2019. One outbuilding was destroyed. As shown on the Cal FIRE FHSZ maps, 165.98 square miles (11.35%) of the county are located in the High FHSZ SRA, while an additional 94.91 square miles (6.49%) of Mariposa County are Extent / located in the Very High FHSZ SRA. Additionally, the Cal FIRE Fire Threat maps show that 722.74 Severity square miles (49.41%) are located in the Very High fire threat areas, and an additional 40.55 square miles (2.77%) are located in Extreme fire threat areas. The climate in Mariposa County is characterized as Mediterranean dry-summer featuring cool, wet winters, and warm, dry summers. High moisture levels during the winter rainy season significantly increase the growth of plants. However, the vegetation dries during the long, hot summers, decreasing plant moisture content and increasing the ratio of dead fuel to living fuel. As a result, fire susceptibility increases dramatically, particularly in late summer and early autumn. In addition, the presence of chaparral, a drought-resistant variety of vegetation that is dependent on occasional wildfires, is common in Mediterranean dry-summer climates. The history of plant succession in Mariposa County is important in predicting fire susceptibility. For several years after Recurrence a fire has occurred, easily flammable herbaceous species thrive and increase the likelihood of new Probability fires. When woody species become re-established, they contribute to a lower overall level of fire susceptibility for approximately 10 years. However, after this period, the slow aging plant community becomes ever more likely to burn because of increased levels of dead plant material and lowered plant moisture levels. Additionally, a regional meteorological phenomenon, known as the Diablo winds, contributes to the high incidence of wildfires in Northern California. These hot and dry offshore winds are particularly dangerous, along with other factors, such as a longer dry season and increasing temperatures. Based upon historical occurrences, Mariposa County fires greater 1,000 acres are likely to occur in Mariposa County every 1 to 3 years.
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MARIPOSA COUNTY LOCAL HAZARD MITIGATION PLAN
Table 4-24. Wildfire Impact on Land Area - Fire Hazard Severity Zones
State Responsibility Area – High State Responsibility Area – Very High Community # of Sq. Miles % of Sq. Miles # of Sq. Miles % of Sq. Miles Mariposa County 165.98 11.35 94.91 6.49 Bear Valley 2.94 40.60 0.80 11.10 Bootjack 0.00 0.00 0.00 0.00 Buck Meadows 0.00 0.00 0.44 25.02 Catheys Valley 5.59 23.82 0.00 0.00 Coulterville 1.00 23.66 0.44 10.34 El Portal 0.00 0.00 0.00 0.01 Fish Camp 0.00 0.00 0.46 50.20 Greeley Hills 0.00 0.00 12.60 59.71 Hornitos 0.00 0.00 0.00 0.00 Lake Don Pedro 11.56 91.97 0.00 0.00 Mariposa 1.29 42.51 0.00 0.00 Midpines 3.63 14.79 10.63 43.32 Wawoma 0.00 0.00 0.00 0.00 Yosemite Valley 0.00 0.00 0.00 0.00
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MARIPOSA COUNTY LOCAL HAZARD MITIGATION PLAN
Table 4-25. Wildfire Impact on Land Area - Fire Threat Areas
Fire Threat Areas – Very High Fire Threat Areas - Extreme Entity # of Sq. Miles % of Sq. Miles # of Sq. Miles % of Sq. Miles Mariposa County 722.74 49.41 40.55 2.77 Bear Valley 5.89 81.33 0.02 0.30 Bootjack 4.61 65.20 1.82 25.76 Buck Meadows 1.27 72.66 0.00 0.00 Catheys Valley 12.43 52.99 0.00 0.00 Coulterville 3.40 80.65 0.00 0.00 El Portal 0.36 34.44 0.00 0.00 Fish Camp 0.73 80.05 0.00 0.00 Greeley Hills 7.93 37.60 0.00 0.00 Hornitos 0.51 43.58 0.30 25.78 Lake Don Pedro 5.05 40.15 4.49 35.70 Mariposa 1.92 62.95 0.00 0.00 Midpines 12.51 50.97 0.00 0.00 Wawoma 4.47 70.40 0.00 0.00 Yosemite Valley 0.01 0.55 0.00 0.00
Table 4-26. Wildfire Impact on Critical Facilities - Fire Hazard Severity Zones
State Responsibility Area – High State Responsibility Area – Very High Facility Type # of Facilities % of Facilities # of Facilities % of Facilities Communications 2 50.00 0 0.00 Community 11 33.33 8 24.24 Education 2 13.33 2 13.33` Emergency 7 30.43 4 17.40 Response Government 12 75.00 0 0.00 Health Services 3 60.00 1 33.33 Historic Places & 4 57.14 0 0.00 Districts Public Works & 7 35.00 4 35.00 Utilities Transportation 1 14.29 1 14.29
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MARIPOSA COUNTY LOCAL HAZARD MITIGATION PLAN
Table 4-27. Wildfire Impact on Critical Facilities - Fire Threat Areas
Fire Threat Areas – Very High Fire Threat Areas - Extreme Facility Type # of Facilities % of Facilities # of Facilities % of Facilities Communications 1 25.00 0 0.00 Community 4 12.12 0 0.00 Education 3 20.00 0 0.00 Emergency 0.00 4 17.40 0 Response Government 1 6.25 0 0.00 Health Services 0 0.00 0 0.00 Historic Places & 0.00 0 0.00 0 Districts Public Works & 0.00 6 30.00 0 Utilities Transportation 1 14.29 0 0.00
Table 4-28. Overall Summary of Vulnerability to Wildfires
Public Safety Power Shutoffs Much of densely forested Mariposa County is vulnerable to wildfires. As shown on the Cal FIRE FRAP maps, nearly 20% of the county is located in a High or Very High FHSZs. Additionally, according to the agency’s Fire Threat maps, over 50 percent of the county is located in a Very High or Extreme fire threat area. However, many areas of higher Summary development density or expected growth are not within the Very High or High FHSZs. Wildfires can destroy habitat, burn down homes, buildings, and critical facilities, cause loss of life to humans and animals, create air pollution and serious health problems, and restrict access to recreational areas.
2020 PAGE | 4-27 T u o l u m n e C o u n t y
Buck Meadows UV120
Greeley Hill Yosemite Valley UV120 UV140 Coulterville UV132
El Portal
140 49 UV Lake Don Pedro UV
M e r c e d C o u n t y UV41
Bear Valley Midpines Wawona
Hornitos UV49 Mariposa Fish Camp Bootjack
UV49 Catheys Valley Ma d e r a C o u n t y
Legend UV140 Census Designate Place (CDP) National Forest / Park . Federal Responsibility Area (FRA) 0 2.5 5 10 Miles State Responsibility Area (SRA) Very High High Fire Hazard Severity Zones Moderate Figure 4-6 Source Fire Resource and Assessment Program 2019 Mariposa County Fire Perimeters Database (2019) https://frap.fire.ca.gov Local Hazard Mitigation Plan T u o l u m n e C o u n t y
Buck Meadows 120
Greeley Hill Yosemite Valley 140
Coulterville 132
El Portal
140 49 Lake Don Pedro
M e r c e d C o u n t y 41
Bear Valley Midpines Wawona
Hornitos 49 Mariposa Fish Camp Bootjack
49 Catheys Valley Ma d e r a C o u n t y
Legend 140 Census Designate Place (CDP) National Forest / Park Fire Threat Low 0 2.5 5 10 Miles Moderate High Fire Threat Areas Very High Figure 4-7 Extreme Source 2019 Mariposa County Wildland Fire Threat (2017) https://frap.fire.ca.gov Local Hazard Mitigation Plan T u o l u m n e C o u n t y
Buck Meadows 120 Rim Fire UV 2013 Creek Fire (256,176 Acres) 2001 (11,095 Acres) Greeley Hill Yosemite Valley UV120 UV140 Coulterville UV132
El Portal
140 UV49 UV Lake Don Pedro Ferguson Fire 2018 Detwiler Fire Telegraph Fire (96,900 Acres) 2017 M e r c e d C o u n t y 2008 UV41 (81,826 Acres) (34,083 Acres)
Bear Valley Midpines Wawona
Hornitos UV49 Ma d e r a C o u n t y Mariposa Fish Camp Bootjack Railroad Fire 2017 49 Catheys Valley UV (12,371 Acres)
UV140 Legend Census Designate Place (CDP) . National Forest / Park 0 2.5 5 10 Miles Burned Areas 10,000 - 49,999 acres 50,000 - 99,999 acres Recent Wildfire Perimeters (2000-2018) 100,000+ acres Figure 4-8 Source Fire Resource and Assessment Program 2019 Mariposa County Fire Perimeters Database (2019) https://frap.fire.ca.gov Local Hazard Mitigation Plan
MARIPOSA COUNTY LOCAL HAZARD MITIGATION PLAN
4.8 WINTER STORM
Table 4-29. Winter Storm Identification Profile
Profile Description A winter storm is an event where snow, sleet, or freezing rain may be accompanied by high winds and cold temperatures. A winter storm can range from a moderate snow over a few hours, to blizzard conditions with blinding wind-driven snow that lasts several days. Some winter storms may Nature be large enough to affect several states, while others may affect only a single community. In more temperate continental climates, such as California, these storms are not necessarily restricted to the winter season and may occur in the late autumn and early spring as well. All of Mariposa County is susceptible to the hazards of a winter storm. The higher elevations of the Location eastern half of the county are most susceptible to all aspects of winter storm, including freezing temperatures, snowfall, and high winds. According to the NOAA Storm Events Database, there have been 60 days of winter storm events in Mariposa County over the past decade. Of these, the federal government declared two severe History winter storm emergencies for Mariposa County, including: • DR-1952, December 17, 2010 – January 4, 2011 • DR-4308, February 1, 2017 – April 1, 2017 NOAA has developed Climate Maps for the United States. Figure 4-9 illustrates the annual mean Extent / total snowfall. For Mariposa County, the areas most susceptible to snowfall can average over 72 Severity inches of snowfall per year, while the areas least susceptible average less than 3 inches of snowfall per year. Recurrence Based upon historical occurrences, Mariposa County can expect to experience winter storm Probability conditions about 5 to 6 days each year.
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MARIPOSA COUNTY LOCAL HAZARD MITIGATION PLAN
Table 4-30. Annual Snowfall Impact on Land Area
High Snowfall Area Community # of Sq. Miles % of Sq. Miles Mariposa County 529.98 36.23 Bear Valley 0.00 0.00 Bootjack 0.00 0.00 Buck Meadows 0.00 0.00 Catheys Valley 0.00 0.00 Coulterville 0.00 0.00 El Portal 0.01 1.24 Fish Camp 0.91 100.00 Greeley Hills 0.00 0.00 Hornitos 0.00 0.00 Lake Don Pedro 0.00 0.00 Mariposa 0.00 0.00 Midpines 0.00 0.00 Wawoma 6.34 100.00 Yosemite Valley 2.12 99.99
Table 4-31. Annual Snowfall Impact on Critical Facilities
High Snowfall Area Community # of Facilities % of Facilities Communications 0 0.00 Community 1 3.03 Education 3 20.00 Emergency Response 1 4.35 Government 0 0.00 Health Services 0 0.00 Historic Places & Districts 0 0.00 Public Works & Utilities 4 20.00 Transportation 1 14.29
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MARIPOSA COUNTY LOCAL HAZARD MITIGATION PLAN
Table 4-32. Overall Summary of Vulnerability to Winter Storm
Winter Storm All of Mariposa County is vulnerable to winter storms. The higher elevations of the eastern half of the county (approximately 36% of the county) are most susceptible. A major winter storm can last for several days and be accompanied by high winds, freezing Summary rain or sleet, heavy snowfall, and cold temperatures. It may knock down trees and powerlines, cause roofs to collapse, lead to dangerous driving conditions and cause drivers to be stranded. It can cause serious health problems, including frostbite, hypothermia, and even death.
2020 PAGE | 4-33 T u o l u m n e C o u n t y
Buck Meadows 120
Greeley Hill Yosemite Valley
120 140
Coulterville 132
El Portal
140 49 Lake Don Pedro
M e r c e d C o u n t y 41
Bear Valley Midpines Wawona
Hornitos 49 Mariposa Fish Camp Bootjack
49 Catheys Valley Ma d e r a C o u n t y
Legend
Census Designate Place (CDP) 140 National Forest / Park Mean Annual Snowfall (inches) 0 - 6.0 (Low) 0 2.5 5 10 Miles 6.1 - 12.0 (Low) 12.1 - 24.0 (Low) 24.1 - 36.0 (Moderate) Mean Annual Snowfall (2017-2018) 36.1 - 48.0 (High) Figure 4-9 >48.1 (High) Source 2019 Mariposa County National Snowfall Analysis (2019) https://www.nohrsc.noaa.gov Local Hazard Mitigation Plan
MARIPOSA COUNTY LOCAL HAZARD MITIGATION PLAN
5.0 MITIGATION STRATEGY
This section addresses Element C of the Local Mitigation Plan Regulation Checklist.
Regulation Checklist – 44 CFR 201.6 Local Mitigation Plans Element C: Mitigation Strategy
C1. Does the Plan document each jurisdiction’s existing authorities, policies, programs and resources and its ability to expand on and improve these existing policies and programs? (Requirement § 201.6(c)(3)) C2. Does the Plan address each jurisdiction’s participation in the NFIP and continued compliance with NFIP requirements, as appropriate? (Requirement § 201.6(c)(3)(i)) C3. Does the Plan include goals to reduce/avoid long‐term vulnerabilities to the identified hazards? (Requirement §201.6(c)(3)(i)) C4. Does the Plan identify and analyze a comprehensive range of specific mitigation actions and projects for each jurisdiction being considered to reduce the effects of hazards, with emphasis on new and existing buildings and infrastructure? (Requirement §201.6(c)(3)(ii)) C5. Does the Plan contain an action plan that describes how the actions identified will be prioritized (including cost benefit review), implemented, and administered by each jurisdiction? (Requirement §201.6(c)(3)(iv)); (Requirement §201.6(c)(3)(iii)) C6. Does the Plan describe a process by which local governments will integrate the requirements of the mitigation plan into other planning mechanisms, such as comprehensive or capital improvement plans, when appropriate? (Requirement §201.6(c)(4)(ii))
5.1 AUTHORITIES, POLICIES, PROGRAMS, AND RESOURCES Mariposa County’s existing authorities, policies, programs and resources available for hazard mitigation are listed in Table 5-1 through Table 5-3. These tables have been updated since the 2015 LHMP to reflect any changes in human, technical, financial, legal, and regulatory resources. As identified in Table 5-4, Mariposa County is looking to expand and improve upon its hazard mitigation authorities by codifying development standards to guide development in the WUI areas, creating an Urban Forest Management Plan and continuing to work with communities to develop Community Conservation Wildfire Protection Plans (CCWPP).
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MARIPOSA COUNTY LOCAL HAZARD MITIGATION PLAN
Table 5-1 Human and Technical Resources for Hazard Mitigation
Staff/Personnel Department / Agency Principal Activities Related to Hazard Mitigation
Planner(s), engineer(s) and Mariposa County Planning Develops and maintains the 2017 Safety Element. technical staff with knowledge of Department Anticipates and acts on the need for new plans, policies, and code changes. land development, land management practices, and Applies the approved plans, policies, code provisions, and other regulations to proposed human-caused and natural land uses. hazards. Engineer(s), Building Mariposa County Building Oversees the effective, efficient, fair, and safe enforcement of the Mariposa County Inspectors/Code Enforcement Department Code. Officers or other professional(s), and technical staff trained in construction requirements Engineers, construction project Mariposa County Public Works Provides direct or contract civil, structural, and mechanical engineering services, managers, and supporting Department including contract, project, and construction management. technical staff Engineer(s), project manager(s), Mariposa County Public Works Maintains and operates of a wide range of local equipment and facilities and assists technical staff, equipment Department members of the public. This includes providing sufficient clean fresh water, reliable operators, and maintenance and sewer services, street maintenance, storm drainage systems, street cleaning, street construction staff lights and traffic signals. Floodplain Administrator Mariposa County Public Works Reviews and ensures that new development proposals do not increase flood risk, and Department that new developments and not located in the SFHA. Emergency Manager Mariposa County OES Maintains and updates the Mariposa County Emergency Response Plan and annexes. In addition, coordinates local response and relief activities in the Emergency Operation Center, and works closely with local, state, and federal partners to support planning and training and to provide information and coordinate assistance. Procurement Services Manager Auditor Provides a full range of municipal financial services, administers several licensing measures. Fire Chief Mariposa County Fire Provides fire protection services including response, fire prevention, and mitigation Department activities for the county. Sheriff Mariposa County Sheriff’s Provides law enforcement services in the county. Office
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MARIPOSA COUNTY LOCAL HAZARD MITIGATION PLAN
Table 5-2. Financial Resources for Hazard Mitigation
Type Administrator Purpose Amount Mariposa County Administrative General Fund Program operations and specific projects. Variable. Officer / Board of Supervisors Mariposa County General obligation bonds are appropriately used for the construction and/or acquisition General Obligation Administrative of improvements to real property broadly available to residents and visitors. Such Variable. Bonds Officer / Board of facilities include but are not limited to: libraries, hospitals, parks, public safety facilities, Supervisors and cultural and educational facilities. Revenue bonds are used to finance capital projects that: 1) have an identified Mariposa County budgetary stream for repayment (e.g., specified fees, tax receipts); 2) generate project Lease Revenue Administrative revenue but rely on a broader pledge of general fund revenues to reduce borrowing Variable. Bonds Officer / Board of costs; or 3) finance the acquisition and installation of equipment for the local Supervisors jurisdiction’s general governmental purposes. Cost-sharing program between Cal FIRE and private land owners, which focuses on Vegetation the use of prescribed fire, mechanical, biological, and chemical means addressing Management Cal FIRE Project-specific. wildland fire fuel hazards and other resource management issues on SRA and LRA Program lands Wildfire Administers funding from the FEMA, Bureau of Land Management, and U.S. Forest Emergency and Cal FIRE Project-specific. Service for certain types of wildfire emergency and mitigation funding. Mitigation Funds Cal Water Funds the purchase of personal protective equipment, firefighting or communications Firefighter Grant Cal Water Service equipment, training and prerequisites material, and educational materials used to Project-specific. Program support fire protection efforts. California California Created by the California Earthquake Authority and the Governor’s Office of Residential Earthquake Emergency Services, Earthquake Brace + Bolt: Funds to Strengthen Your Foundation Project-specific. Mitigation Authority is the first incentive program offered by the California Residential Mitigation Program. Program Hazard Mitigation Supports pre- and post-disaster mitigation plans and projects. Available to California Grant Program FEMA communities after a presidentially declared disaster has occurred in California, Project-specific. (HMGP) administered by Cal OES. Building Resilient Focuses on reducing the nation’s risk by funding public infrastructure projects that Infrastructure and FEMA increase a community’s resilience before a disaster affects an area. BRIC will replace Project-specific. Communities the Pre-Disaster Mitigation program in 2020. (BRIC)
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MARIPOSA COUNTY LOCAL HAZARD MITIGATION PLAN
Table 5-2. Financial Resources for Hazard Mitigation
Type Administrator Purpose Amount Homeland Security Build and sustain preparedness technical assistance activities in support of the four Preparedness FEMA/DHS homeland security mission areas (i.e., prevention, protection, response, recovery) and Project-specific. Technical homeland security program management. Assistance Program Provides equipment, protective gear, emergency vehicles, training, and other Assistance to FEMA/U.S. Fire resources needed to protect the public and emergency personnel from fire and related Firefighters Grant Project-specific. Administration hazards. Available to fire departments and nonaffiliated emergency medical services Program providers. Allow communities to make the preemptive investment into aging infrastructure and in The National Dam the process make the communities below a dam safer. Eligible projects include dams Rehabilitation FEMA determined to be high-hazard potential by the State Dam Safety Program, have an Project-specific. Program Emergency Action Plan approved by the State Dam Safety Program and fail to meet minimum dam safety standards or pose an unacceptable risk to the public are eligible. Rural Schools Act Provides that title III funds may be used to reimburse counties for search and rescue U.S Department of – Title III County and other emergency response activities, including firefighting and law enforcement Project-specific. Agriculture Funds patrols, performed on national forests Intended to expand limited federal capacity to implement and plan forest, rangeland, and watershed restoration projects by facilitating partnerships with state agencies. The Good Neighbor U.S Department of authority allows a state to perform authorized restoration services, including habitat Project-specific. Authority Agriculture improvement, fuels management, fire related activities, insect and disease control, project planning, project preparation work, and commercial timber removal, on federal land. Land and Water U.S. Department of Supports the protection of federal public lands and waters and voluntary conservation Conservation Project-specific. the Interior on private land. Funds Through financial and technical assistance offers an innovative way for a community Community Action U.S. Environmental to organize and take action to reduce toxic pollution (e.g., stormwater) in its local for a Renewed Protection Agency environment. Through this program, a community creates a partnership that Project-specific. Environment (EPA) implements solutions to reduce releases of toxic pollutants and minimize people’s exposure to them.
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Table 5-2. Financial Resources for Hazard Mitigation
Type Administrator Purpose Amount A loan program that provides low-cost financing to eligible entities on state and tribal Clean Water State lands for water quality projects, including all types of non-point source, watershed U.S. EPA Project-specific. Revolving Fund protection or restoration, estuary management projects, and more traditional municipal wastewater treatment projects. Community Block Acquisition of real property, relocation and demolition, rehabilitation of residential and Grant Program U.S. Department of non-residential structures, construction of public facilities and improvements, such as Entitlement Housing and Urban Project-specific. water and sewer facilities, streets, neighborhood centers, and the conversion of school Communities Development buildings for eligible purposes. Grants
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Table 5-3. Legal and Regulatory Resources for Hazard Mitigation
Potential to Emergency Name Description Hazards Addressed Affect Management Development Describes hazard areas and lists goals and policies to reduce Mitigation, Flood, earthquake, 2017 Safety Element the potential risk of death, injuries, and economic damage Preparedness, Yes landslide, and wildfire resulting from natural and human-caused hazards. Response Identifies and prioritizes pre-fire and post-fire management Madera – Mariposa – Preparedness, strategies and tactics meant to reduce the loss of values at Wildfire Yes Merced Strategic Fire Plan Mitigation risk in Mariposa County. Mariposa County Code: Promotes public health, safety, and general welfare through Flood, earthquake, Mitigation Yes Titles 8, 15, 16 and 17 laws enforced locally. landslide, and wildfire Contains minimum requirements relating to the organization and deployment of fire suppression operations, emergency medical operations, and special operations to the public by the Mitigation, Mariposa County Fire Fire Department. Address functions and outcomes of fire Preparedness, Departments Standards of department emergency service delivery, response capabilities, Fire Yes Response and Cover (2010) and resources. Contains minimum requirements for managing Recovery resources and systems such as health and safety, incident management, training, communications, and pre-incident planning. Requires the County of Mariposa Fire Plan Unit to implement Preparedness, California Fire Plan the California Fire Plan, a statewide framework for minimizing Wildfire Yes Mitigation costs and losses from wildland fires.
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5.2 NATIONAL FLOOD INSURANCE PROGRAM PARTICIPATION The NFIP aims to reduce the impact of flooding to residential and non-residential buildings. It does so by providing insurance to property owners and by encouraging communities to adopt and enforce floodplain management regulations. Mariposa County does not participate in the NFIP. Localized flood and associated debris issues are managed by the Mariposa County Public Works Department.
5.3 MITIGATION GOALS Mitigation goals are defined as general guidelines that explain what a community wants to achieve in terms of hazard and loss prevention. Goal statements are typically long-range, policy-oriented statements representing community-wide vision. For the 2020 LHMP, the goals have been revised to reflect goals outlined in the Mariposa County Recreation and Resiliency Master Plan framework, including: • Reduce the county’s risk to natural and human-caused disasters, including climate change, drought, earthquake, flood, landslide, public safety power shutoff, wildfire, and winter storm. • Support local, state, and federal partners before, during, and after a disaster. • Facilitate healthy and safe lifestyles from changes in the region’s climate.
5.4 RECOMMENDED IMPLEMENTATION MEASURES Mitigation actions help achieve the goals of the LHMP. For the 2020 LHMP, mitigation actions are referred to as implementation measures to reflect the terminology used in other County documents. The recommended implementation measures in Table 5-4 include: education and awareness; natural systems protection; structure and infrastructure projects; preparedness and response; and local plans and regulations. This list addresses every hazard profiled in this plan and is based on the plan’s risk assessment as well as lessons learned from recent disasters. It was developed using FEMA success stories and best management practices, FEMA job aids, local and regional plans and reports, and input from the planning committee.
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Table 5-4. Recommended Implementation Measures
No. Project Name Project Description Hazards Mitigated Project Source Create an online and offline public outreach campaign for Red Flag Warnings. Include Best practices, 2019 information about: what is a Red Flag Warning; what Red Flag Warning Public Public safety power shutoff Mariposa County Public 1 land may be closed; and what individuals should do Outreach and wildfire Safety Power Shutoff to be prepared as well as what activities should be Response Plan avoided. Tailor outreach material to various target groups, such as older populations and tourists. Fireproof coat critical facilities in Very High FHSZs Critical Facility Fireproof 2 which will allow structures to extend their strength in Wildfire Best practices Coating the event of a fire. Determine which critical facilities require auxiliary power in order to remain functional during de- energization or public safety power shutoff and/or Critical Facility Auxiliary Public safety power shutoff, 3 general loss of power and install auxiliary power Best practices Power wildfire, and winter storm systems. Auxiliary power systems may include back- up generators, local Solar Photovoltaic plus storage, and microgrids. WUI Classification Expand WUI to include moderate and high FHSZ 2019 Mariposa County 4 Wildfire Expansion Policy classifications. CPAW Extend defensible space requirements to include a Zone 2. Zone 2 extends 100 feet out from buildings, 2019 Mariposa County Defensible Space structures, decks, etc., and includes cutting/moving 5 Climate change and wildfire CPAW, Cal FIRE best Enhancement Program grasses, creating horizontal and vertical spacing practices between grasses, shrubs and trees, and removing fallen leaves and needles. Develop a countywide SIZ assessment program for homeowners in which mitigation specialists visit interested homeowners to develop a comprehensive Structure Ignition Zone 6 report recommending mitigation actions to take. If Wildfire 2019 CPAW (SIZ) Assessment Program funding exists, develop a grant program to assist homeowners with implementing recommended actions items.
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Table 5-4. Recommended Implementation Measures
No. Project Name Project Description Hazards Mitigated Project Source Identify property owners that have property that are large enough to encompass significant fuel loads Beyond Defensible Space 7 and to be difficult to maintain adequately and small Climate change and wildfire Planning Committee Zone Program enough to fall below any existing efforts for prescribed fire support or grazing campaigns. Determine/acquire a large site suitable for large- Incident Command Post / scale Incident Command Post/Base Camp 8 Base Camp Operations Operations. Ensure site is not located in hazard Earthquake and wildfire Mariposa County Site areas and carry out appropriate mitigation efforts, if needed, including fire breaks and auxiliary power. Adopt a WUI ordinance/overlay zone for areas that are located in the FHSZs. Properties within this overlay area are often subject to additional WUI Ordinance / Overlay 9 standards concerning structure density and location, Wildfire 2017 Safety Element Zone building materials and construction, vegetation management, emergency vehicle access, water supply, and fire protection. Adopt a comprehensive flood protection ordinance/overlay zone for areas that are located in the SFHA or subject to flooding. Properties within County Flood Protection 10 this overlay are often subject to additional standards Flood 2017 Safety Element Ordinance / Overlay Zone concerning development/land uses, building elevation, stream buffers, outdoor storage, building materials, and permitting procedures. Adopt a hillside protection ordinance/overlay zone to address natural features, steep slopes, viewsheds, and dangerous geologic conditions. The County Hillside Protection Landslide, wildfire and winter 11 ordinance/overlay can include provisions for special 2017 Safety Element Ordinance / Overlay Zone storm procedures, suitability analysis requirements, grading, landscaping, building height, and sometimes wildfire mitigation standards.
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Table 5-4. Recommended Implementation Measures
No. Project Name Project Description Hazards Mitigated Project Source Adopt a dam failure inundation ordinance/overlay zone to increase preparation and protection from County Dam Failure flood events due to dam failure. The 12 Inundation Ordinance / Flood and winter storm 2017 Safety Element ordinance/overlay can include provisions for Overlay Zone development and land uses as well as evacuation protocol. Install more water storage tanks to be available for 2014 Mariposa County 13 Water Storage Tanks use during periods of prolonged droughts and also Drought and wildfire Drought Preparedness Plan, to be used for firefighting capabilities. Planning Committee Develop a coordinated large-scale fuel break Large-Scale Fuel Break program that maps when and where fuel breaks 14 Wildfire Planning Committee Program have been developed and maintained and carry out fuel break measures where needed. Establish a program to assist dam owners rehabilitate or remove dams that do not meet current safety standards and/or are nearing the end of their Climate change, drought, Dam Rehabilitation 15 design life. Many of these dams supply Mariposa wildfire, flood, earthquake, Planning Committee Program County with drinking water and recreation and also and wildfire play an important role in providing water for firefighting.
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5.5 IMPLEMENTATION PLAN An implementation plan (referred to in the Local Mitigation Planning Handbook as a mitigation action plan) is a prioritized list of recommended implementation measures that a community hopes to put into practice in order to reduce its risks and vulnerabilities. In order to determine which implementation measures are most important, the planning committee identified three clear priority areas that an implementation measure must meet. • Life-safety potential • Positive benefit-cost potential • Wildfire reduction potential As shown in Table 5-5, there are 11 recommended implementation measures that meet the three priority areas identified above. These measures have been assigned a priority of “high,” while the remaining number of recommended implementation measures identified in Table 5-4 have been assigned a priority of “moderate”. For each implementation measure listed in Table 5-5, potential funding sources, responsible department/agency, and timing have been identified.
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Table 5-5. Prioritized Implementation Plan
Potential Funding No. Project Name Priority Responsibility Timing Source Red Flag Warning Public FEMA, Cal FIRE or Cal Mariposa County Sheriff’s 1-year development, 1 High Outreach Water Service Office ongoing Mariposa County Public Critical Facility Fireproof Works Department, 2 High FEMA 1-3 years implementation Coating Mariposa County Fire Department Critical Facility Auxiliary Mariposa County Public 3 High FEMA 1-5 years implementation Power Works Department Mariposa County Fire WUI Classification Department, Mariposa 4 High FEMA or Cal FIRE 1-year development Expansion Policy County Planning Department Defensible Space Mariposa County Fire 5 High FEMA or Cal FIRE 1-year development Enhancement Program Department Structure Ignition Zone Mariposa County Fire 1-year development, 6 High FEMA or Cal FIRE (SIZ) Assessment Program Department ongoing Beyond Defensible Space Mariposa County Fire 1-year development, 7 High FEMA or Cal FIRE Zone Program Department ongoing Incident Command Post / Mariposa County Sheriff’s 8 Base Camp Operations Moderate Local or FEMA 1-3 years implementation Office Site Mariposa County Fire WUI Ordinance / Overlay Department, Mariposa 9 High Local 1-year development Zone County Planning Department Mariposa County Public County Flood Protection Works Department, 10 Moderate Local 1-year development Ordinance / Overlay Zone Mariposa County Planning Department County Hillside Protection Mariposa County Planning 11 Moderate Local 1-year development Ordinance / Overlay Zone Department
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Table 5-5. Prioritized Implementation Plan
Potential Funding No. Project Name Priority Responsibility Timing Source County Dam Failure Mariposa County Planning 12 Inundation Ordinance / Moderate Local 1-year development Department Overlay Zone Mariposa County Fire 13 Water Storage Tanks High Local or FEMA 1-2 years implementation Department Large-Scale Fuel Break Mariposa County Fire 14 High FEMA or Cal FIRE 1-3 years implementation Program Department Dam Rehabilitation Mariposa County Public 15 High FEMA 1-5 years implementation Program Works Department
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5.6 PLAN INTEGRATION The County incorporated the 2015 LHMP into the following two other County planning documents over the past 5 years: • County of Mariposa General Plan – Volume 1, Safety Element (2017). The plan includes references 2015 LHMP’s hazard profiles and the entire mitigation strategy. • The Mariposa County CPAW (2019). The plan references the 2015 LHMP as part of a peer document review. Moving forward, the LHMP project manager will work with the following departments to ensure further plan integration: • Mariposa County Planning Department to ensure that the 2020 LHMP is included in the County of Mariposa General Plan – Volume 1, Safety Element review. • Mariposa County OES to ensure that the 2020 LHMP public safety power shutoff and wildfire hazard profiles and associated implementation actions are reviewed and incorporated into the 2020 CCWPP.
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6.0 PLAN REVIEW, EVALUATION AND IMPLEMENTATION
This section addresses Element D of the Local Mitigation Plan Regulation Checklist.
Regulation Checklist – 44 CFR 201.6 Local Mitigation Plans Element D: Plan Review, Evaluation and Implementation
D1. Was the plan revised to reflect changes in development? (Requirement § 201.6(d)(3)) D2. Was the plan revised to reflect progress in local mitigation efforts? (Requirement § 201.6(d)(3)) D3. Was the plan revised to reflect changes in priorities? Requirement §201.6(d)(3))
6.1 CHANGES IN DEVELOPMENT As stated in Section 3.2, there has been little population or development change since the 2015 LHMP. However, the population has been steadily aging over the past several decades. According to the CCWPP, older demographics are often associated with fixed incomes, limited mobility and/or capabilities to install or maintain migration projects. These concerns are addressed in the 2020 LHMP mitigation strategy.
6.2 PROGRESS IN LOCAL MITIGATION EFFORTS The 2015 LHMP Mitigation Actions Matrix was reviewed by each of the coordinating County agencies identified on the matrix in order to determine project status. Mitigation actions that were identified as not having been implemented or deferred were considered for Table 5-4. Mitigation actions that were identified as completed are shown in Table 6-1.
Table 6-1. 2015 LHMP Implemented Mitigation Actions
No. Description Implementation 2 Integrate the Mariposa County LHMP, in particular the 2015 LHMP was referenced in the and the hazard analysis and mitigation strategy sections, into (2017) County of Mariposa General Plan – local planning documents, including general plans, Volume 1, Safety Element and the 2019 emergency operations plans, and capital improvement CPAW. plans. 20 Implement a fuel reduction program, such as the collection and disposal of dead fuel in open spaces and See #21 and #23 around critical facilities and residential structures that are located in hazardous fuel buildup areas. 21 Create a vegetation management program that provides Mariposa County Fire Safe Council vegetation management services to elderly, disabled, or implemented a number of vegetation low-income property owners who lack the resources to management programs for low or fixed remove flammable vegetation from around their homes. income, disabled, disabled veterans, senior citizens, and/or PG&E Care customers. Programs include: chipping and brushing, weed eating, and tree mortality assistance. 23 Develop and provide funding and/or incentives for Mariposa County Fire Safe Council defensible space measures (e.g., free collection day for implemented a Downed Tree Removal tree limbs). Program to help Mariposa's North County residents with the means to remove downed trees from their defensible space.
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Table 6-1. 2015 LHMP Implemented Mitigation Actions
No. Description Implementation 31 Manage vegetation in areas in and adjacent to rights-of- Mariposa County Public Works way and in close proximity to critical facilities in order to Department continues to mitigate tree reduce the risk of tree failure and property damage and mortality hazards along County- avoid creation of wind acceleration corridors within maintained roadways and properties. vegetated areas.
6.3 CHANGES IN PRIORITIES Similar to the 2015 LHMP prioritization process, the 2020 LHMP priorities still include expected future damage and loss reduction (i.e., positive benefit-cost) and high-risk (i.e., life-safety) criteria. However, the 2020 LHMP prioritization process replaces multi-hazard mitigation with wildfire reduction. The county has always experienced frequent fires but current and forecasted changes to climate conditions are expected to further exacerbate this hazard and therefore, an urgency in mitigating it.
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7.0 PLAN ADOPTION
Section 7 – Plan Adoption addresses Element E of the Local Mitigation Plan Regulation Checklist. Regulation Checklist – 44 CFR 201.6 Local Mitigation Plans
Element E: Plan Adoption E1. Does the Plan include documentation that the plan has been formally adopted by the governing body of the jurisdiction requesting approval? (Requirement §201.6(c)(5)) E2. For multi‐jurisdictional plans, has each jurisdiction requesting approval of the plan documented formal plan adoption? (Requirement §201.6(c)(5))
7.1 FORMAL ADOPTION The 2020 LHMP was formally adopted by the Mariposa County Board of Supervisors via resolution on [To be completed]. A scanned copy of the resolution is included as Figure 7-1. It will also be kept on file with the Mariposa County OES and additionally be sent to Cal OES and FEMA.
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ADOPTION RESOLUTION
2020
MARIPOSA COUNTY LOCAL HAZARD MITIGATION PLAN
APPENDIX A—PLANNING PROCESS
2020 Mariposa County Local Hazard Mitigation Plan
Planning Committee Meeting 1 Agenda Introductions Mitigation Planning Overview Local Hazard Mitigation Plan Overview Questions & Answers Introductions Mitigation Planning Overview What is mitigation planning? Hazard mitigation planning – commonly referred to as “mitigation planning” - is the effort to reduce loss of life and property by lessening the impact of disasters. It is key to breaking the cycle of disaster damage, reconstruction and repeated damage. Why mitigation planning? State, tribal, and local governments engage in hazard mitigation planning to identify risks and vulnerabilities associated with natural disasters and develop long-term strategies for protecting people and property from future hazard events. AND….. FEMA-approved mitigation plans allow governmental entities to seek certain types of non- emergency disaster assistance. Disaster Mitigation Act of 2000 Disaster Mitigation Act of 2000, signed into law in October 2000 (PL 100-390). Section 322 requires a revitalized approach to hazard mitigation through State, tribal, and local planning. States, tribal, and local governments must have a FEMA -approved mitigation plan to receive certain types of mitigation funding. Mitigation plans must be written, adopted and approved (and subsequently updated) every 5 years. Local Mitigation Plan Review Guide The Local Mitigation Plan Review Guide is FEMA’s updated policy on, and interpretation of, the requirements for Local Mitigation Planning found at 44 Code of Federal Regulations Part 201, Mitigation Planning. The Local Review Tool (within the guide) includes 40 sub elements that must be addressed in order for the plan to be approved by FEMA. https://www.fema.gov/media-library/assets/documents/23194 Local Hazard Mitigation Plan Overview Local Hazard Mitigation Plan Outline Introduction Planning Process Community Profile Hazard Identification* & Risk Assessment Mitigation Strategy* Plan Review, Evaluation and Implementation Plan Adoption Hazards Identification Climate Change Drought Earthquake Flood Landslide Public Safety Power Shutoff Wildfire Winter Storm Mitigation Strategy Mitigation projects (also known as mitigation measures or mitigation actions) reduce the risk of loss of life and property from future disasters. They provide long term solutions to a problem and generally are categorized as: Preventive Floodplain management regulatory/current and future conditions Property protection Natural resource protection activities Emergency services Structural projects Public information and education Mitigation Project Funding Eligibility FEMA funding eligibility, mitigation projects must: Provide a long -term solution to a problem Have a potential savings more than the cost of implementing the project Solve the problem independently (phased projects must be completed as one project) Must be completed in a 5 -year timeframe Mitigation Project Ideas Examples of projects include, but are not limited to: Acquisition of real property for willing sellers and demolition or relocation of buildings to convert the property to open space use Retrofitting structures and facilities to minimize damage from high winds, earthquake, flood, wildfire, or other natural hazards Development and initial implementation of vegetative management programs Minor flood control projects that do not duplicate the flood prevention activities of other federal agencies Localized flood control projects, such as certain ring levees and floodwall systems, that are designed specifically to protect critical facilities Back-up generators and alternatives to back-up generators Mitigation Project Format (Example 1)
Project Name Emergency Power (Shelter Generators)
Provide additional emergency power, such as a generator equipment, for new and existing critical facilities to operate Description continuously but cannot do so for long durations of power outage.
Two shelter locations have been identified with a need for back-up power improvements. At least two new trailer Additional Information mounted diesel generator sets with quick connection cables and temporary fencing will be required.
Administrator Building and Safety, Community Services, Facilities, Emergency Management
Timeframe 4 Years
Potential Funding FEMA Hazard Mitigation Grant Program funding Task Date Update the plan October – November 2019 Internal draft Week of December 8, 2019 Public draft Week of December 15, 2019 Final draft Week of January 5 or 12, 2020 Cal OES / FEMA review January – March 2020
Mariposa County Local Hazard Mitigation Schedule Task Date Review risk assessment Week of November 17, 2019 Review draft mitigation strategy Week of November 24, 2019 Review internal draft Week of December 8, 2019
Planning Committee Schedule Questions & Answers Mariposa County Local Hazard Mitigation Plan
Planning Committee Meeting 2 Agenda Mitigation Strategy Overview Mitigation Goals Recommended Mitigation Actions Prioritized Mitigation Action Plan Next Steps Mitigation Strategy Overview Mitigation Strategy The mitigation strategy describes how the community will accomplish the overall purpose, or mission, of the planning process. It is made up of three main required components: mitigation goals, mitigation actions and an action plan for implementation. These provide the framework to identify, prioritize and implement actions to reduce risk to hazards. Mitigation Goals Mitigation Goals Mitigation goals are general guidelines that explain what the community wants to achieve with the LHMP. They are usually broad policy-type statements that are long term, and they represent visions for reducing or avoiding losses from the identified hazards. The LHMP must include two or more goals to reduce/avoid long-term vulnerabilities to the identified hazards. Should the goals in the 2015 LHMP be updated or should new ones be developed? Please see “Mission and Goals Comparison Sheet”. Recommended Mitigation Actions Mitigation Actions A mitigation action is a specific action, project, activity, or process taken to reduce or eliminate long-term risk to people and property from hazards and their impacts. Mitigation activities lessen or eliminate the need for preparedness or response resources in the future. Mitigation actions can also be referred to as mitigation projects and implementation measures. Implementing mitigation actions helps achieve the LHMP’s mission and goals. Types Mitigation Actions Mitigation actions include: 1. local plans and regulations 2. structure and infrastructure projects 3. natural systems protection 4. education and awareness programs LHMP’s may also include emergency response or operational preparedness actions. Mitigation Project Examples Examples of projects include, but are not limited to: 1. Acquisition of real property for willing sellers and demolition or relocation of buildings to convert the property to open space use 2. Retrofitting structures and facilities to minimize damage from high winds, earthquake, flood, wildfire, or other natural hazards 3. Elevation of flood-prone structures 4. Development and initial implementation of vegetative management programs 5. Minor flood control projects that do not duplicate the flood prevention activities of other federal agencies 6. Public outreach campaigns 7. Back-up generators and alternatives to back-up generators FEMA-funded Mitigation Projects FEMA funding eligibility, mitigation projects must: Provide a long-term solution to a problem. Have a potential savings more than the cost of implementing the project. Solve the problem independently (phased projects must be completed as one project). Not be a continuation of a program or an existing maintenance program. Must be completed in a 5-year timeframe. 2020 LHMP Recommended Mitigation Actions Mitigation actions identified in the 2015 LHMP were reviewed and progress with their implementation is documented in the 2020 LHMP. 10 new / updated mitigation actions have been developed to -date. Project sources include the 2020 LHMP risk assessment, County department input, other County plans, and best practices. The mitigation action plan must include one mitigation action per hazard…could use an EQ retrofit project. Are there other mitigation actions / projects / measures to be considered? Please see “Recommended Mitigation Actions List”. Prioritized Mitigation Action Plan Prioritization of Mitigation Actions
FEMA requires that the LHMP contain a list of prioritized mitigation actions, which are “the most suitable mitigation actions for the community to implement.” It is up to the community to decide how to prioritize the mitigation actions. FEMA’s only requirement is that benefit-cost must be considered….that is to say, does the project make financial sense? 2015 LHMP Prioritization Process For the 2015 LHMP, each project was reviewed against the following criteria: 1. The action can be implemented during the 5-year lifespan of the HMP 2. The action may reduce expected future damages and losses (a positive cost-benefit analysis appears likely) 3. The action mitigates a high-risk hazard 4. The action mitigates multiple hazards Projects that met 3 or more of the above criteria were included in the 2015 LHMP mitigation action plan. 2020 LHMP Prioritization Process Should the 2015 LHMP prioritization process be updated? Prioritization process ideas for the 2020 LHMP: All projects identified in the recommended mitigation action plan list should be included in the prioritized mitigation action plan. Projects should be ranked “high or medium” priority. Prioritization criteria should include: life-safety, benefit-cost and wildfire hazards. The prioritization process above helps identify projects that are eligible and most competitive for FEMA grant funding. Next Steps Next Steps 1. Finalize recommended mitigation actions list. 2. Prioritize mitigation action plan based on Planning Committee input. 3. Create internal draft plan week of December 8 for Planning Committee Review. 4. Create public draft plan week of December 15.
Alyssa Carroll
The Mariposa County Sheriff’s Office/Office of Emergency Services is updating the County’s Local Hazard Mitigation Plan. Over the next few months, we will re-assess risks posed by disasters, review and revise existing strategies, as well as develop new ones to protect life and property in future events.
Hazards addressed in our plan include: climate change, drought, earthquake, flood, landslide, public safety power shutoff, and wildfire. Once our plan is completed and approved by FEMA, the County will be re-eligible to apply for and receive certain types of non-emergency disaster assistance, including funding for mitigation projects identified in our plan.
To learn more about hazard mitigation planning, please visit: https://www.fema.gov/hazard-mitigation- planning.
To learn more about our plan, please follow our Twitter account @MariposaSheriff or our Facebook page: Mariposa County Sheriff’s Office.
If you would like to participate in our planning process, please contact me at the Mariposa County Sheriff’s Office/Office of Emergency Services.
We will send out a follow-up email when our Public Draft is available for review and comment. Thank you.
Alyssa Carroll Mariposa County Sheriff’s Office/OES Deputy Sheriff/Deputy ESC/Deputy SAR Coordinator 5099 Old Highway North Mariposa, CA 95338 (209) 966-3615 ext. 307
MARIPOSA COUNTY LOCAL HAZARD MITIGATION PLAN
APPENDIX B—COMMUNITY PROFILE
2020 Table B-1. Type, Name and Location of Local Critical Facilities
Type of Facility Name of Facility Location of Facility Communication KRYZ Mariposa Communication AT&T Coulterville Communication Sierra Telecom Mariposa Communication TDS Telecom Mariposa Community Arts Park Mariposa Community Autopark Midpines Community Catheys Valley Community Center Catheys Valley Community Chamber Of Commerce - Visitors Center Mariposa Community Clarke Community Hall El Portal Community Coulterville Community Center Coulterville Community Coulterville Park Coulterville Community Darrah Park & School House Mariposa Community El Portal Library El Portal Community Greeley Hill Community Clubhouse Greeley Hill Community Greeley Hill Library Greeley Hill Community Homeless Shelter Mariposa Community Hornitos Stagg Hall & Park Hornitos Community Horseshoe Bend Rec. Area Coulterville Community Lake McClure Point Rec. Area Snelling Community Mariposa County History Center Coulterville Community Mariposa County Jail Mariposa Community Mariposa County Library Mariposa Community Mariposa County Park Mariposa Community Mariposa County Rest Area Mariposa Community Mariposa County Senior Center Mariposa Community Mariposa County Swimming Pool Mariposa Community Mariposa Fairgrounds Mariposa Community Mariposa Mining & Mineral Museum Mariposa Community Midpines Community Center Midpines Community Midpines Trailer Park Midpines Community New Life Church Mariposa Community Old McClure Point Marina Don Pedro Community Red Cloud Park Coulterville Community SPCA of Mariposa County Mariposa Community Wampum Hill Trailer Park Coulterville Table B-1. Type, Name and Location of Local Critical Facilities
Type of Facility Name of Facility Location of Facility Community Wawona Library Wawona Community Woodland Park & Hall Mariposa Education Alternative Education Programs Mariposa Education Coulterville High School Coulterville Education El Portal Residences El Portal Education El Portal School & Yosemite Park High School El Portal Education Greeley Hill Elementary Greeley Hill Education Hornitos School (closed site) Hornitos Education Lake Don Pedro School Elementary School La Grange Education Mariposa County High School Mariposa Education Mariposa Elementary School Mariposa Education School District Office Mariposa Education Sierra Foothill Charter School Catheys Valley Education Woodland School Mariposa Education Yosemite School Residence - House 1 El Portal Education Yosemite School Residence - House 2 El Portal Yosemite School Residence - Triplex, Units 1,2 Education El Portal and 3 Emergency Response County Fire Administration Office Mariposa Emergency Response Fire Station - Bootjack (#37) Mariposa Emergency Response Fire Station - Bridgeport (#28) Mariposa Emergency Response Fire Station - Catheys Valley (#23) Catheys Valley Emergency Response Fire Station - Coulterville (#26) Coulterville Emergency Response Fire Station - Don Pedro (#24) La Grange Emergency Response Fire Station - El Portal (#34) El Portal Emergency Response Fire Station - Fish Camp (#33) Fish Camp Emergency Response Fire Station - Greeley Hill (#31) Coulterville Emergency Response Fire Station - Hunters Valley (#36) Mariposa Emergency Response Fire Station - Lushmeadows (#29) Mariposa Emergency Response Fire Station - Mariposa PUD Mariposa Emergency Response Fire Station - Midpines (#21) Mariposa Emergency Response Fire Station - Mormon Bar (#27) Mariposa Emergency Response Fire Station - MPUD (#22) Mariposa Emergency Response Fire Station - Mt Bullion (#25) Mariposa Emergency Response Fire Station - Ponderosa Basin (#32) Mariposa Emergency Response Sheriff’s Office Mariposa Table B-1. Type, Name and Location of Local Critical Facilities
Type of Facility Name of Facility Location of Facility Emergency Response Sheriff’s Office/Dispatch Mariposa Emergency Response Sheriff's Office Greeley Hill Substation Coulterville Emergency Response Sheriff's Office La Grange Substation La Grange Emergency Response Sheriff's Office/Detective Unit Mariposa Emergency Response Sheriff's Office/OES Mariposa Government Animal Control Mariposa Government Jerseydale Landing Zone Jerseydale Lake Don Pedro Maintenance Building and Boat Government La Grange Yard Mariposa County Community Health Government Mariposa Center/County Health Department Government Mariposa County DA Mariposa Government Mariposa County Data Processing/IT Mariposa Government Mariposa County Family Support Mariposa Government Mariposa County Fish & Game Mariposa Government Mariposa County Government Center Mariposa Government Mariposa County Hall of Records Mariposa Government Mariposa County Human Services Mariposa Government Mariposa County Maintenance Building. Mariposa Government Mariposa County Parks & Recreation Mariposa Government Mariposa County Probation Mariposa Government Mariposa County Transit Mariposa Government Mariposa County VA Services Mariposa Health Indian Health Clinic Mariposa Health John C. Fremont North County Clinic Greeley Hill Health John C. Fremont Healthcare District Mariposa Health Mariposa Personal Health Clinic Mariposa Health Mariposa Pines Villa Mariposa Coulterville Main Street Historic District Historic Places Coulterville (#82002205) Historic Places Hornitos Masonic Hall No. 98 (#05000775) Hornitos Historic Places Mariposa County Courthouse (#77000306) Mariposa Mariposa County High School Auditorium Historic Places Mariposa (#91000547) Historic Places Mariposa County Jail - Historic Mariposa Historic Places Mariposa Town Historic District (#91000560) Mariposa Table B-1. Type, Name and Location of Local Critical Facilities
Type of Facility Name of Facility Location of Facility St. Joseph Catholic Church, Rectory and Historic Places Mariposa Cemetery (#91000424) Public Works/Utilities Coulterville Sewer Coulterville Public Works/Utilities Coulterville Sewer Lift Station Coulterville Public Works/Utilities Coulterville Water Coulterville Public Works/Utilities Exchequer Dam La Grange Public Works/Utilities Fish Camp Transfer Station Fish Camp Public Works/Utilities Hornitos Transfer Station Hornitos Public Works/Utilities Lake Don Pedro Sewer Treatment La Grange Public Works/Utilities Lake Don Pedro Transfer Station La Grange Public Works/Utilities Lake McClure Spillway and Powerhouse Don Pedro Public Works/Utilities Mariposa County Land Fill Mariposa Public Works/Utilities Mariposa Pines Sewer Lift Station Mariposa Public Works/Utilities Mariposa Pines Treatment Mariposa Mariposa Public Utility District - Mariposa Public Works/Utilities Mariposa Reservoir Public Works/Utilities Mc Swain Powerhouse Hornitos Mariposa Public Utility District - Wastewater Public Works/Utilities Mariposa Facility Public Works/Utilities Ponderosa Basin Water Company Mariposa Public Works/Utilities Public Works Administration Mariposa Public Works/Utilities Saxon Pump Station Mariposa Public Works/Utilities Yosemite West Sewer Yosemite National Park Public Works/Utilities Yosemite West Water Yosemite National Park Transportation Mariposa County Airport Mariposa Transportation Slate Creek Bridge Midpines Transportation William Sell Bridge Mariposa Transportation Yarts Bus Stop El Portal Transportation Yarts Bus Stop - Inbound - Hornitos Catheys Valley Transportation Yarts Bus Stop - Outbound Catheys Valley Transportation Yarts Park & Ride - Howard Street Mariposa