San Joaquin County
California — Natural Disaster Risk Assessment
HighComposite Risk Score
National percentile: 99th
San Joaquin County faces high composite natural disaster risk (NRI Risk Index score 98.6, 99th national percentile), driven primarily by drought and earthquake exposure. Expected annual loss across all 18 hazard types is $422M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Top Hazards
All 18 Hazard Risks
| Drought | Very High | 68.55 / yr | $83M |
| Earthquake | High | 0.11 / yr | $184M |
| Riverine Flood | High | 1.11 / yr | $138M |
| Heat Wave | High | 6.98 / yr | $11M |
| Lightning | High | 7.70 / yr | $2M |
| Wildfire | Medium | 0.00 / yr | $2M |
| Volcanic Activity | Very Low | 0.00 / yr | $515 |
| Landslide | Very Low | 7.42 / yr | $3K |
| Hail | Low | 0.07 / yr | $316K |
| Tornado | Low | 0.18 / yr | $1M |
| Winter Weather | Low | 0.20 / yr | $49K |
| Strong Wind | Low | 0.05 / yr | $384K |
| Avalanche | Very Low | 0.01 / yr | $0 |
| Coastal Flood | Very Low | 0.00 / yr | $0 |
| Cold Wave | Very Low | 0.00 / yr | $0 |
| Hurricane | Very Low | 0.00 / yr | $0 |
| Ice Storm | Very Low | 0.00 / yr | $0 |
| Tsunami | Very Low | 0.00 / yr | $0 |
Frequently Asked Questions
What is the overall natural disaster risk for San Joaquin County?
San Joaquin County has a composite FEMA National Risk Index score of 98.6 out of 100, placing it in the High category and the 99th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in San Joaquin County?
The three highest-rated hazards are Drought (Very High, $83M EAL), Earthquake (High, $184M EAL), Riverine Flood (High, $138M EAL). These account for most of the county's expected annual losses.
How does San Joaquin County compare to other California counties?
San Joaquin County ranks #17 of 58 California counties for overall natural disaster risk, with a high rating.
What does Expected Annual Loss (EAL) mean?
EAL is FEMA's estimate of average annual dollar losses from natural hazards, calculated from historical event data and exposure models. San Joaquin County's $422M EAL is a statistical average, not a guarantee for any specific year or address.