Solano County— fire, flood & earthquake hazard information
Solano County is a county in the San Francisco Bay Area, covering about 821.7 square miles. This page summarizes what official government maps show for Solano County: 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 Solano County’s area that falls inside each mapped zone.
View Solano County on the interactive map → to check any specific address, free.
Wildfire hazard severity zones
Per CAL FIRE's Fire Hazard Severity Zone maps, 2% of Solano County is in a Very High fire hazard severity zone, 5% is in a High zone, 7% is in a Moderate zone. The remainder of its area is outside currently designated zones.
| Very High severity zone | 2% |
| High severity zone | 5% |
| Moderate severity zone | 7% |
FEMA flood zones
35% of Solano County lies within a FEMA Special Flood Hazard Area (1% annual chance, zones A/AE/AH/AO); less than 1% is in a coastal high hazard zone (V/VE); 2% 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) | 35% |
| Coastal high hazard (V/VE) | less than 1% |
| 0.2% annual chance (500-yr) | 2% |
Earthquake faults & seismic zones
The nearest mapped fault, the Rio Vista fault, is about 1.6 mi (2.6 km) from the center of Solano County. 11 named fault traces in the USGS Quaternary fault database cross its boundary. less than 1% falls within an Alquist-Priolo earthquake fault zone, where new construction requires a fault study.
| Nearest mapped fault | Rio Vista fault — 1.6 mi (2.6 km) |
| Named fault traces crossing boundary | 11 |
| Alquist-Priolo fault zone | less than 1% |
Dam inundation, aircraft noise & air quality
6% of Solano County lies within a state-reviewed dam-failure inundation area; annual average fine-particle (PM2.5) concentration across its census tracts is 8.3 μg/m³, and its composite pollution burden ranks around the 65th percentile statewide.
| Dam-failure inundation area | 6% |
| Annual PM2.5 (tract average) | 8.3 μg/m³ |
| Pollution burden percentile (statewide) | ~65 |
Frequently asked questions
- Is Solano County in a wildfire hazard severity zone?
- Per CAL FIRE's Fire Hazard Severity Zone maps, 2% of Solano County is in a Very High fire hazard severity zone, 5% is in a High zone, 7% is in a Moderate zone. The remainder of its area is outside currently designated zones.
- Is Solano County in a FEMA flood zone?
- 35% of Solano County lies within a FEMA Special Flood Hazard Area (1% annual chance, zones A/AE/AH/AO); less than 1% is in a coastal high hazard zone (V/VE); 2% 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 Solano County?
- The nearest mapped fault, the Rio Vista fault, is about 1.6 mi (2.6 km) from the center of Solano County. 11 named fault traces in the USGS Quaternary fault database cross its boundary. less than 1% falls within an Alquist-Priolo earthquake fault zone, where new construction requires a fault study.
- How do I check a specific address in Solano County?
- Use the free sitelume interactive map at https://sitelume.com — search any Solano County address to see which mapped zones it falls in, layer by layer.
Cities in Solano 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.