Tamalpais-Homestead Valley, CA— fire, flood & earthquake hazard information
Tamalpais-Homestead Valley is a unincorporated community in Marin County in the San Francisco Bay Area, covering about 4.7 square miles. This page summarizes what official government maps show for Tamalpais-Homestead Valley: CAL FIRE fire hazard severity zones, FEMA flood zones, state seismic hazard zones, dam inundation areas, airport noise contours, and air-quality indicators. Figures are the share of Tamalpais-Homestead Valley’s area that falls inside each mapped zone.
View Tamalpais-Homestead Valley on the interactive map → to check any specific address, free.
Wildfire hazard severity zones
Per CAL FIRE's Fire Hazard Severity Zone maps, 39% of Tamalpais-Homestead Valley is in a Very High fire hazard severity zone, 2% is in a High zone, less than 1% is in a Moderate zone. The remainder of its area is outside currently designated zones.
| Very High severity zone | 39% |
| High severity zone | 2% |
| Moderate severity zone | less than 1% |
FEMA flood zones
6% of Tamalpais-Homestead Valley lies within a FEMA Special Flood Hazard Area (1% annual chance, zones A/AE/AH/AO); less than 1% is in the 0.2% annual chance (500-year) area. Federally backed mortgages in a Special Flood Hazard Area generally require flood insurance.
| Special Flood Hazard Area (100-yr) | 6% |
| 0.2% annual chance (500-yr) | less than 1% |
Earthquake faults & seismic zones
The nearest mapped fault, the San Andreas fault zone, is about 7.7 mi (12.4 km) from the center of Tamalpais-Homestead Valley.
| Nearest mapped fault | San Andreas fault zone — 7.7 mi (12.4 km) |
Dam inundation, aircraft noise & air quality
annual average fine-particle (PM2.5) concentration across its census tracts is 8.3 μg/m³, and its composite pollution burden ranks around the 15th percentile statewide.
| Annual PM2.5 (tract average) | 8.3 μg/m³ |
| Pollution burden percentile (statewide) | ~15 |
Frequently asked questions
- Is Tamalpais-Homestead Valley in a wildfire hazard severity zone?
- Per CAL FIRE's Fire Hazard Severity Zone maps, 39% of Tamalpais-Homestead Valley is in a Very High fire hazard severity zone, 2% is in a High zone, less than 1% is in a Moderate zone. The remainder of its area is outside currently designated zones.
- Is Tamalpais-Homestead Valley in a FEMA flood zone?
- 6% of Tamalpais-Homestead Valley lies within a FEMA Special Flood Hazard Area (1% annual chance, zones A/AE/AH/AO); less than 1% is in the 0.2% annual chance (500-year) area. Federally backed mortgages in a Special Flood Hazard Area generally require flood insurance.
- What earthquake faults and seismic zones affect Tamalpais-Homestead Valley?
- The nearest mapped fault, the San Andreas fault zone, is about 7.7 mi (12.4 km) from the center of Tamalpais-Homestead Valley.
- How do I check a specific address in Tamalpais-Homestead Valley?
- Use the free sitelume interactive map at https://sitelume.com — search any Tamalpais-Homestead Valley address to see which mapped zones it falls in, layer by layer.
Nearby in Marin County
Sources: CAL FIRE Fire Hazard Severity Zones; FEMA National Flood Hazard Layer; USGS Quaternary Faults; CGS Seismic Hazard Zones & Alquist-Priolo zones; Cal OES dam inundation maps; county ALUC noise contours; CalEnviroScreen 4.0. Area shares are computed against each place’s Census TIGER boundary (last computed 2026-07-24). Boundaries and zone designations change; always verify with the issuing agency.