San Diego, California climate resilience brief

Priority hazards

• Wildfire and smoke exposurehigh confidence
• Atmospheric-river flooding and landslidesmedium-high confidence
• Drought and water-supply reliabilitymedium confidence

Exposure and vulnerability

Priority groups

older adults, low-income renters, outdoor workers, medically dependent residents, students

Assets

WUI homes, evacuation routes, storm drains, canyon slopes, water tanks, libraries and clinics, substations

Use current local exposure, public health, infrastructure, and social vulnerability data before acting.

Adaptation options

• WUI home-hardening and evacuation-corridor packageNeeds parcel prioritization, owner participation, CAL FIRE map verification, and utility coordination for PSPS risk.Cost: medium-high · Benefit: Reduced structure loss, fewer smoke/evacuation emergencies, more reliable emergency access.
• Clean-air/cooling resilience hubs with backup powerSites have structural capacity, community access, ADA compliance, and operations agreements.Cost: medium · Benefit: Protects medically vulnerable residents during smoke, heat, and outages.
• Atmospheric-river drainage and slope stabilization programRequires storm-drain condition data, geotechnical screening, permits, and maintenance funding.Cost: medium-high · Benefit: Cuts flood closures, landslide repair costs, and stormwater pollution pulses.

Cost and benefit ranges are planning estimates, not procurement-ready budgets.

Implementation timeline

Short term

• Map San Diego WUI, drainage, PSPS, and vulnerable-facility overlaps using Cal-Adapt and local asset data.
• Select 3 resilience hubs and 5 evacuation/drainage hot spots for design scoping.

Mid term

• Apply for CAL FIRE, California Climate Investments, FEMA BRIC/HMGP, and state water funding with bundled projects.
• Construct hub power/filtration upgrades and first-phase culvert, slope, and defensible-space works.

Long term

• Institutionalize annual WUI inspections, storm-drain clearing, and hub exercises before fire and atmospheric-river seasons.
• Scale recycled-water, storage, and drought-demand projects with regional water districts.

Funding windows

• CAL FIRE Wildfire Prevention Grantsstate grant · Match: often 0-25%; verify current NOFO · Award: $250k-$5M typical screening range · O&M: limited; mainly planning, treatment, education, and implementation
• California Climate Investments / Transformative Climate Communities and related programsstate cap-and-invest funding · Match: varies; verify administering agency · Award: $500k-$20M depending on program · O&M: some planning and community implementation; long-term O&M limited
• FEMA BRIC or Hazard Mitigation Grant Programfederal mitigation grant · Match: generally 25% nonfederal, with exceptions · Award: $500k-$50M depending on project and competition · O&M: generally no routine O&M

Decision triggers

• If Red Flag Warning plus forecast Santa Ana winds affecting San Diego WUI areasThen Pre-stage crews, open clean-air/cooling hubs, message evacuation routes, and coordinate with CAL FIRE and utilities on PSPS risk.
• If Atmospheric-river forecast with rainfall intensity likely to exceed local drainage design at known canyon outfallsThen Clear inlets, close flood-prone road segments early, inspect slopes, and activate public works storm shifts.
• If Regional water districts declare drought shortage stage or imported-water allocation cutThen Activate municipal drought operations, protect critical facilities, expand rebates, and defer nonessential irrigation.

Evidence and sources

• Wildfire, smoke, and PSPS risk are material for San Diego WUI neighborhoods.expert inference; verify with CAL FIRE hazard maps, City/County wildfire plans, utility PSPS records
• Atmospheric rivers can drive flood, erosion, and landslide impacts in San Diego's urban canyons.expert inference; verify with Cal-Adapt, city stormwater records, USGS/California Geological Survey data
• Drought resilience depends on regional imported-water management and local conservation/reuse.expert inference; verify with San Diego County Water Authority and regional water districts plans

Governance and verification

Steps

• Emergency management lead: create a San Diego compound-risk steering group with fire, water, public works, health, and community partners.
• Public works lead: rank WUI, drainage, hub, and water projects in one capital pipeline with Cal-Adapt/CAL FIRE evidence.
• City grants lead: package projects for CAL FIRE, California Climate Investments, FEMA, and state water funding with local match strategy.

Partners

City of San Diego Stormwater/Public Works Department for canyon drainage and culvert delivery, San Diego Fire-Rescue and CAL FIRE for WUI inspections, evacuation planning, and fuel priorities, San Diego County Water Authority and regional water districts for drought reliability and reuse projects, San Diego libraries, schools, clinics, and community-based organizations for clean-air/cooling hub operations

Priority sites

Canyon-rim WUI neighborhoods and evacuation corridors exposed to wildfire, smoke, and PSPS risk, Low crossings, culverts, and slope toes below San Diego canyons exposed to atmospheric-river flooding, Libraries, recreation centers, clinics, and schools suitable for clean-air/cooling hubs in vulnerable neighborhoods

Metrics

number of WUI parcels hardened, hub seats with filtered air and backup power, culverts/slope sites upgraded, hours of critical-facility backup power, acre-feet saved or reused