Alameda County
California — Natural Disaster Risk Assessment
Very HighComposite Risk Score
National percentile: 100th
Alameda County faces very high composite natural disaster risk (NRI Risk Index score 99.8, 100th national percentile), driven primarily by earthquake and landslide exposure. Expected annual loss across all 18 hazard types is $1.88B.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Top Hazards
All 18 Hazard Risks
| Earthquake | Very High | 0.14 / yr | $1.35B |
| Landslide | High | 24.63 / yr | $6M |
| Riverine Flood | Very High | 2.25 / yr | $491M |
| Wildfire | High | 0.01 / yr | $12M |
| Heat Wave | High | 7.10 / yr | $13M |
| Coastal Flood | High | 0.98 / yr | $5M |
| Drought | Medium | 58.43 / yr | $1M |
| Volcanic Activity | Very Low | 0.00 / yr | $348 |
| Tornado | Medium | 0.09 / yr | $2M |
| Tsunami | Low | 0.34 / yr | $3M |
| Lightning | Low | 4.50 / yr | $235K |
| Hail | Low | 0.04 / yr | $167K |
| Strong Wind | Very Low | 0.04 / yr | $94K |
| Avalanche | Very Low | 0.01 / yr | $4 |
| Winter Weather | Very Low | 0.69 / yr | $3K |
| Cold Wave | Very Low | 0.00 / yr | $0 |
| Hurricane | Very Low | 0.00 / yr | $0 |
| Ice Storm | Very Low | 0.00 / yr | $0 |
Frequently Asked Questions
What is the overall natural disaster risk for Alameda County?
Alameda County has a composite FEMA National Risk Index score of 99.8 out of 100, placing it in the Very High category and the 100th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Alameda County?
The three highest-rated hazards are Earthquake (Very High, $1.35B EAL), Landslide (High, $6M EAL), Riverine Flood (Very High, $491M EAL). These account for most of the county's expected annual losses.
How does Alameda County compare to other California counties?
Alameda County ranks #3 of 58 California counties for overall natural disaster risk, with a very 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. Alameda County's $1.88B EAL is a statistical average, not a guarantee for any specific year or address.