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Natural hazard risk in Imperial County, California

Updated October 30, 2026. Based on FEMA, NOAA and OpenFEMA data. Published by Humblebee.

FEMA overall Risk Index rating: Relatively High (score 96.4 of 100)[5]

Expected annual loss (FEMA)
$147.6 million[1]
Federal disaster declarations since 1976
13[2]
NFIP flood claims paid, 1978 to 2026
$560,000[3]
Tornadoes recorded, 1950 to 2024
7[4]

FEMA's National Risk Index rates overall natural hazard risk in Imperial County as Relatively High, with a Risk Index score of 96.4 out of 100[5]. The hazards with the highest FEMA scores in the county are earthquake, inland flooding and heat wave[6].

FEMA risk ratings for each hazard

Ratings and expected losses from the FEMA National Risk Index. Each rating compares this county with all US counties for that hazard, from Very Low to Very High. They are planning estimates, not predictions, and they do not describe any single property.

FEMA's National Risk Index (version 1.20, December 2025) estimates Expected Annual Loss from all 18 natural hazards in Imperial County at $147.6 million a year[1]. This is a FEMA estimate of average yearly loss, not money anyone paid[7]. The largest parts of that loss come from earthquake ($100.9 million a year), inland flooding ($42.5 million a year) and heat wave ($3.1 million a year)[8]. FEMA rates social vulnerability Very High, which describes how susceptible social groups are to harm from natural hazards[9]. FEMA rates community resilience Very Low, which describes a community's ability to prepare for, withstand and recover from hazards[10]. All ratings compare Imperial County with other US counties[7].

Hazards sorted by FEMA hazard-type Risk Index score, highest first
HazardFEMA risk ratingExpected annual loss
EarthquakeRelatively High$100.9 million[11]
Inland FloodingRelatively High$42.5 million[12]
Heat WaveRelatively Moderate$3.1 million[13]
Volcanic ActivityRelatively Low$2,372[14]
WildfireRelatively Low$184,000[15]
DroughtRelatively Moderate$321,000[16]
Strong WindRelatively Moderate$401,000[17]
LandslideVery Low$459[18]
HurricaneVery Low$4,743[19]
HailVery Low$46,000[20]
LightningVery Low$35,000[21]
TornadoVery Low$53,000[22]
Winter WeatherVery Low$0[23]

Rated Not Applicable by FEMA for this county: avalanche, coastal flooding, ice storm, tsunami[24].

Social vulnerability and community resilience

FEMA uses these two ratings to scale expected losses into the Risk Index.

FEMA measureRatingScore
Social vulnerabilityVery High85.1[9]
Community resilienceVery Low2.4[10]

Flooding and flood insurance

FEMA rates inland flooding risk Relatively High compared with other US counties, with an Expected Annual Loss of $42.5 million a year[12]. OpenFEMA lists 33 residential flood insurance contracts in force in the county as of 2026-08-03[25]. Inside FEMA's mapped Special Flood Hazard Area, 4.2% of homes are insured[25]. OpenFEMA's NFIP claims show 103 claims filed for losses from 1978 to 2026, and NFIP paid $560,000 in total[3]. To learn about a specific address, use FEMA's Flood Map Service Center[26].

Measure Value
Inland Flooding, FEMA risk rating[12] Relatively High, $42.5 million expected loss a year
NFIP residential flood policies in force (2026)[25] 33 of 42,918 homes
Homes in FEMA's mapped high-risk flood area (SFHA)[25] 601, of which 25 insured
NFIP flood claims, 1978 to 2026[3] 103 filed, $560,000 paid

Is a specific address in a flood zone? Only FEMA's flood maps answer that, property by property[26]. This page describes the whole county.

Search an address on the FEMA Flood Map Service Center

Disaster declarations and tornado records

OpenFEMA lists 13 federal disaster declarations for natural hazards that include Imperial County since 1976[2]. The most recent was DR-4750-CA, Tropical Storm Hilary, declared 2023-11-21[27]. NOAA's tornado database records 7 tornadoes that touched the county from 1950 to 2024, and the strongest were rated F1[4].

Federal disaster declarations for natural hazards that include Imperial County, since 1976
Incident type Declarations
Flood[2] 4
Severe Storm[2] 3
Hurricane[2] 2
Earthquake[2] 2
Freezing[2] 2
Most recent declarations
Declaration Incident Declared
DR-4750-CA[27] Tropical Storm Hilary 2023-11-21
DR-4699-CA[27] Severe Winter Storms, Straight-Line Winds, Flooding, Landslides, And Mudslides 2023-04-03
EM-3592-CA[27] Severe Winter Storms, Flooding, Landslides, And Mudslides 2023-03-10
DR-1911-CA[27] Earthquake 2010-05-07
DR-1884-CA[27] Severe Winter Storms, Flooding, And Debris And Mud Flows 2010-03-08

How to prepare

Steps from Ready.gov, FEMA's preparedness site, for the hazards with the highest FEMA ratings here. Follow instructions from local officials and the National Weather Service when a warning is issued.

Earthquakes

Before

  • Practice Drop, Cover, and Hold On with your family and coworkers.
  • Sign up for earthquake alerts that can warn you before shaking starts.
  • Make a plan with an out-of-state contact and a place to meet if you get separated.
  • Anchor heavy items such as bookcases, refrigerators and water heaters, and keep heavy things on low shelves.
  • Consider earthquake insurance. Standard homeowners policies do not cover earthquake damage.

During

  • Drop to your hands and knees, cover your head and neck, and hold on until the shaking stops.
  • Indoors, stay where you are and avoid doorways. Outdoors, move to an open area away from buildings and power lines.
  • If you are driving, pull over, stop and set the parking brake.

Source: Ready.gov, earthquakes

Floods

Before

  • Check your flood risk with FEMA's Flood Map Service Center, and remember that floods do not follow map lines.
  • Sign up for your community's warning system. NOAA Weather Radio also broadcasts alerts.
  • Buy flood insurance through the NFIP well before a disaster. Homeowners policies do not cover flooding, and a new policy typically takes up to 30 days to go into effect.
  • Make a household plan with evacuation routes, shelter locations and what to do in a flash flood.
  • Keep important documents in a waterproof container and make password-protected digital copies.

During

  • If you are told to evacuate, leave right away and never drive around barricades.
  • Do not walk, swim or drive through floodwater. Six inches of moving water can knock you down.
  • If you are trapped in a building, go to the highest level, but do not climb into a closed attic.

Source: Ready.gov, floods

Extreme heat

Before

  • Learn the signs of heat illness and how to respond.
  • Do not rely on a fan as your main way to stay cool. Fans do not lower body temperature.
  • Find cool public places, such as libraries or malls, or ask your local health department.
  • Keep heat out with window shades, weather stripping and insulation.
  • If you cannot afford cooling costs, contact LIHEAP for help.

During

  • Never leave a person or an animal in a parked car in warm weather.
  • If your home has no air conditioning, go to a cooling center.
  • Wear light, loose clothing, drink plenty of fluids and avoid hard outdoor work in the middle of the day.

Source: Ready.gov, extreme heat

Questions people ask

Is Imperial County at risk of flooding?
FEMA rates inland flooding risk Relatively High compared with other US counties[12]. For a specific address, use FEMA's Flood Map Service Center[26].
Is Imperial County at risk of earthquakes?
FEMA rates earthquake risk Relatively High compared with other US counties, with a score of 99.2 out of 100[11].
Is Imperial County at risk of tornadoes?
FEMA rates tornado risk Very Low compared with other US counties[22]. NOAA's tornado database records 7 tornadoes from 1950 to 2024[4].
How many disasters have been declared in Imperial County?
OpenFEMA lists 13 federal disaster declarations for natural hazards that include the county since 1976[2].
How do I check a flood zone?
FEMA's Flood Map Service Center is the official public source for flood maps. You can look up an address there or ask the local floodplain manager[26].

Facts and sources

  1. FEMA National Risk Index (version 1.20, December 2025): Expected Annual Loss from all 18 natural hazards in Imperial County is $147.6 million a year (Expected Annual Loss rating Relatively Moderate, score 94.0). Of this, buildings account for $115.9 million, injuries and deaths (converted to dollars by FEMA) for... FEMA National Risk Index
  2. OpenFEMA Disaster Declarations Summaries list 13 federal disaster declarations for natural hazards that include Imperial County since 1976 (11 major disaster, 2 emergency or fire management). By incident type: flood 4, severe storm 3, hurricane 2, earthquake 2, freezing 2. Biological (such as COVID-19) and other... OpenFEMA Disaster Declarations
  3. HazardFacts tally of OpenFEMA NFIP Redacted Claims (losses from 1978 to 2026): 103 National Flood Insurance Program claims were filed for losses in Imperial County, 67 of them with a payment, and NFIP paid $560,000 in total (building, contents and increased cost of compliance, in dollars of the year paid). Years... OpenFEMA NFIP claims
  4. NOAA Storm Prediction Center tornado database (1950 to 2024): 7 recorded tornadoes touched Imperial County. The strongest were rated F1 (most recent of them on 1993-08-29). 0 were rated F3/EF3 or stronger. The most recent recorded tornado was on 2000-08-30. Ratings used the Fujita scale until early 2007 and the... NOAA Storm Prediction Center
  5. FEMA National Risk Index (version 1.20, December 2025): the overall natural hazard Risk Index rating for Imperial County is Relatively High, with a Risk Index score of 96.4 out of 100. The score is the county's percentile rank among all US counties. FEMA National Risk Index
  6. Among the 18 hazards in the FEMA National Risk Index (version 1.20, December 2025), the hazards with the highest hazard-type Risk Index scores for Imperial County are earthquake (99.2, Relatively High), inland flooding (94.1, Relatively High), heat wave (93.9, Relatively Moderate). HazardFacts sorted FEMA's... FEMA National Risk Index
  7. FEMA's National Risk Index FAQ (December 2025): Expected Annual Loss is FEMA's estimate of the average economic loss in dollars from natural hazards each year. The index is not meant to predict how much damage a community will have in the next year, and a hazard can still cause damage where a rating is low. Scores... FEMA National Risk Index documentation
  8. HazardFacts sorted FEMA's hazard-type Expected Annual Loss values for Imperial County (National Risk Index v1.20): the largest are earthquake ($100.9 million a year), inland flooding ($42.5 million a year), heat wave ($3.1 million a year), out of $147.6 million a year from all 18 hazards. FEMA National Risk Index
  9. FEMA National Risk Index (version 1.20, December 2025): Social Vulnerability rating for Imperial County is Very High (score 85.1). FEMA describes social vulnerability as how susceptible social groups are to the harm natural hazards cause. FEMA National Risk Index
  10. FEMA National Risk Index (version 1.20, December 2025): Community Resilience rating for Imperial County is Very Low (score 2.4). FEMA describes community resilience as a community's ability to prepare for, withstand and recover from hazards. FEMA National Risk Index
  11. FEMA National Risk Index (version 1.20, December 2025), earthquake in Imperial County: Risk Index rating Relatively High (score 99.2 of 100). Expected Annual Loss $100.9 million a year (rating Relatively High). FEMA's modeled annual frequency is 0.1515 events per year. FEMA National Risk Index
  12. FEMA National Risk Index (version 1.20, December 2025), inland flooding in Imperial County: Risk Index rating Relatively High (score 94.1 of 100). Expected Annual Loss $42.5 million a year (rating Relatively Moderate). Annualized frequency 1.54 event-days per year, from recorded occurrences over a period of record... FEMA National Risk Index
  13. FEMA National Risk Index (version 1.20, December 2025), heat wave in Imperial County: Risk Index rating Relatively Moderate (score 93.9 of 100). Expected Annual Loss $3.1 million a year (rating Relatively Moderate). Annualized frequency 16.9 event-days per year, from recorded occurrences over a period of record of... FEMA National Risk Index
  14. FEMA National Risk Index (version 1.20, December 2025), volcanic activity in Imperial County: Risk Index rating Relatively Low (score 85.9 of 100). Expected Annual Loss $2,372 a year (rating Relatively Low). FEMA National Risk Index
  15. FEMA National Risk Index (version 1.20, December 2025), wildfire in Imperial County: Risk Index rating Relatively Low (score 76.0 of 100). Expected Annual Loss $184,000 a year (rating Relatively Low). FEMA's modeled annual frequency is 0.0008 events per year. FEMA National Risk Index
  16. FEMA National Risk Index (version 1.20, December 2025), drought in Imperial County: Risk Index rating Relatively Moderate (score 69.2 of 100). Expected Annual Loss $321,000 a year (rating Relatively Low). Annualized frequency 39.28 event-days per year, from recorded occurrences over a period of record of 22 years. FEMA National Risk Index
  17. FEMA National Risk Index (version 1.20, December 2025), strong wind in Imperial County: Risk Index rating Relatively Moderate (score 54.6 of 100). Expected Annual Loss $401,000 a year (rating Relatively Low). Annualized frequency 0.28 events per year, from recorded occurrences over a period of record of 38 years. FEMA National Risk Index
  18. FEMA National Risk Index (version 1.20, December 2025), landslide in Imperial County: Risk Index rating Very Low (score 41.2 of 100). Expected Annual Loss $459 a year (rating Very Low). FEMA National Risk Index
  19. FEMA National Risk Index (version 1.20, December 2025), hurricane in Imperial County: Risk Index rating Very Low (score 22.3 of 100). Expected Annual Loss $4,743 a year (rating Very Low). Annualized frequency 0.02 events per year, from recorded occurrences over a period of record of 172 years for the Atlantic Basin... FEMA National Risk Index
  20. FEMA National Risk Index (version 1.20, December 2025), hail in Imperial County: Risk Index rating Very Low (score 20.2 of 100). Expected Annual Loss $46,000 a year (rating Very Low). Annualized frequency 0.05 events per year, from recorded occurrences over a period of record of 37 years. FEMA National Risk Index
  21. FEMA National Risk Index (version 1.20, December 2025), lightning in Imperial County: Risk Index rating Very Low (score 15.9 of 100). Expected Annual Loss $35,000 a year (rating Very Low). Annualized frequency 11.27 events per year, from recorded occurrences over a period of record of 24 years. FEMA National Risk Index
  22. FEMA National Risk Index (version 1.20, December 2025), tornado in Imperial County: Risk Index rating Very Low (score 11.3 of 100). Expected Annual Loss $53,000 a year (rating Very Low). Annualized frequency 0.1 events per year, from recorded occurrences over a period of record of 38 years. FEMA National Risk Index
  23. FEMA National Risk Index (version 1.20, December 2025), winter weather in Imperial County: Risk Index rating Very Low (score 1.1 of 100). Expected Annual Loss $0 a year (rating Very Low). Annualized frequency 0 events per year, from recorded occurrences over a period of record of 18 years. FEMA National Risk Index
  24. FEMA National Risk Index (version 1.20, December 2025) rates these hazards Not Applicable for Imperial County: avalanche, coastal flooding, ice storm, tsunami. FEMA uses Not Applicable when its source data has no historical record of the hazard in the community and the hazard is not considered geographically... FEMA National Risk Index documentation
  25. NFIP Residential Penetration Rates (OpenFEMA, as of 2026-08-03): 33 residential flood insurance contracts were in force in Imperial County, out of 42,918 residential structures, a penetration rate of 0.1%. Inside FEMA's mapped Special Flood Hazard Area there were 601 residential structures and 25 contracts, a rate... OpenFEMA NFIP penetration rates
  26. FEMA's Flood Map Service Center is the official public source for flood maps (Flood Insurance Rate Maps) produced under the National Flood Insurance Program. Flood zones apply to specific properties: look up an address there or ask the local floodplain manager. County-level ratings do not tell you the flood zone of... FEMA Flood Map Service Center
  27. Most recent federal disaster declarations for natural hazards (table on this page). OpenFEMA Disaster Declarations

FEMA's National Risk Index compares each county with all other US counties. Ratings are relative (Very Low to Very High), not a measure of safety. Never call a place safe, unsafe, good or bad to live in. Risk Index and Expected Annual Loss values are FEMA estimates for planning. They do not predict next year's losses and do not apply to a single property. Flood zones are set by FEMA flood maps for specific properties. County ratings and flood insurance counts do not tell anyone whether an address is in a flood zone. Disaster declaration, NFIP and tornado counts are records of the past for this county only. Do not compare with other counties unless a fact does.

Federal Emergency Management Agency (FEMA), National Risk Index Dataset: National Risk Index Counties, v1.20 (December 2025). Retrieved from fema.maps.arcgis.com on October 30, 2026. This product uses the Federal Emergency Management Agency's National Risk Index dataset API or downloadable datasets but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s). This product uses the FEMA OpenFEMA API, but is not endorsed by FEMA.