Imperial County, CA
FEMA National Risk Index scores, disaster declarations & hazard data
Imperial County has experienced 15 federally declared disasters since 1976, most recently Tropical Storm Hilary in 2024. Its overall natural hazard risk is rated Relatively High — higher risk than most US counties.
Imperial County's highest-rated hazards are earthquake, inland flooding, and heat wave, with its top risk rated "Relatively High" by FEMA's National Risk Index. Recorded storm events have increased 122% over the past five years compared to the prior five-year period. Community vulnerability is elevated (99th percentile nationally), suggesting residents may face greater difficulty recovering from major disasters.
Past disasters & FEMA designations
A federal disaster declaration officially designates a county for FEMA disaster assistance. Imperial County has been designated in 15 declarations since 1976, covering 6 disaster types including flood (4), severe storm (3), hurricane (2).
| Year | Type | Event name |
|---|---|---|
| 2024 | Hurricane | Tropical Storm Hilary |
| 2023 | Severe Storm | Severe Winter Storms, Straight-Line Winds, Flooding, Landslides, And Mudslides |
| 2023 | Flood | Severe Winter Storms, Flooding, Landslides, And Mudslides |
| 2020 | Biological | Covid-19 Pandemic |
| 2020 | Biological | Covid-19 |
| 2010 | Severe Storm | Severe Winter Storms, Flooding, And Debris And Mud Flows |
| 2010 | Earthquake | Earthquake |
| 2007 | Freezing | Severe Freeze |
| 2005 | Hurricane | Hurricane Katrina Evacuation |
| 1995 | Severe Storm | Severe Winter Storms, Flooding Landslides, Mud Flow |
Showing the 10 most recent of 15 total declarations since 1976.
Source: FEMA OpenFEMA Disaster Declarations Summaries. A single disaster can produce more than one record per county. Data current through September 2026.
Risk by hazard type
| Hazard | Risk rating | Risk score | Recorded events | Deaths | Prop. damage |
|---|---|---|---|---|---|
| Wildfire | Relatively Low | 76 | 0 | 0 | — |
| Inland Flooding | Relatively High | 94.1 | 98 | 2 | $38.0M |
| Coastal Flooding | Not Applicable | — | 0 | 0 | — |
| Earthquake | Relatively High | 99.2 | 1590 | — | — |
| Heat Wave | Relatively Moderate | 94 | 47 | 0 | — |
| Tornado | Very Low | 11.4 | 0 | 0 | — |
| Hurricane | Very Low | 22.3 | 0 | 0 | — |
| Hail | Very Low | 20.2 | 0 | 0 | — |
| Strong Wind | Relatively Moderate | 54.7 | 0 | 0 | — |
| Winter Weather | Very Low | 1.1 | 0 | 0 | — |
| Ice Storm | Not Applicable | — | — | — | — |
| Cold Wave | No Rating | 0 | — | — | — |
| Lightning | Very Low | 16 | 0 | 0 | — |
| Drought | Relatively Moderate | 69.2 | 0 | 0 | — |
| Landslide | Very Low | 41.2 | 0 | 0 | — |
| Avalanche | Not Applicable | — | — | — | — |
| Tsunami | Not Applicable | — | — | — | — |
| Volcanic Activity | Relatively Low | 86 | — | — | — |
Scores are 0–100 percentiles relative to all US counties — higher means more exposed, not that a disaster is likely this year. Event counts: NOAA Storm Events 2016–2026; earthquake counts from USGS ComCat (M3.0+, 1996–2026). See the methodology page for details.
Community vulnerability
Imperial County ranks in the 99th percentile (High) for community vulnerability — a measure of how hard disaster impacts tend to hit residents. Higher vulnerability means more displacement, worse health outcomes, and slower recovery after a disaster.
| SVI theme | Percentile | Vulnerability level |
|---|---|---|
| Overall | 99th | High |
| Socioeconomic status | 97th | High |
| Household characteristics | 94th | High |
| Racial & ethnic minority status | 99th | High |
| Housing type & transportation | 98th | High |
Source: CDC/ATSDR Social Vulnerability Index 2022. Percentiles compare counties nationally — higher means more vulnerable relative to other counties. See CDC SVI for full methodology.
Future risk outlook
| Wildfire metric | National percentile | Level |
|---|---|---|
| Burn probability | 38th | Relatively Low |
| Risk to homes | 37th | Relatively Low |
| Buildings in direct exposure zone | 17.4% | — |
NOAA tracked 145 weather events in this county over 2016–2025: 45 in 2016–20 vs 100 in 2021–25 (+122% — frequency increasing).
Wildfire: USDA Forest Service Wildfire Risk to Communities (RDS-2020-0016-2) — modeled values, not annual forecasts. See wildfirerisk.org. Inland flood and heat projections pending data availability; coastal sea-level projections are available for select coastal counties below — see the data page.
Nearby counties
Frequently asked questions
What natural hazards pose the greatest risk in Imperial County?
According to the FEMA National Risk Index, the highest-risk hazards in Imperial County, California are earthquake, inland flooding, and heat wave. The county's overall natural hazard risk is rated Relatively High — higher risk than most US counties.
Has Imperial County received federal disaster declarations?
Yes. Imperial County has received 15 federal disaster declarations since 1976, including declarations in 2024. The most common disaster type on record is flood (4 declarations).
Has Imperial County had any FEMA disaster declarations in 2024, 2025, or 2026?
Yes. Recent federal disaster declarations for Imperial County include Tropical Storm Hilary (2024). See the declarations table above for the full history since 1976.
How does Imperial County's natural hazard risk compare to nearby counties?
Among neighboring counties, Riverside County, CA has the highest overall natural hazard risk (Very High) and La Paz County, AZ has the lowest (Relatively Moderate). Imperial County is rated Relatively High overall.
How is Imperial County's composite disaster risk index calculated?
Imperial County's composite disaster risk index — officially FEMA's National Risk Index (NRI) — scores every US county on a 0–100 percentile scale across 18 natural hazard types, factoring in expected annual loss, social vulnerability, and community resilience. Imperial County's composite score of 97 means its overall natural hazard risk is higher than 97% of US counties.