Elmore County, Idaho Natural Disaster Risk
FEMA National Risk Index assessment · ID
LowComposite Risk Score
National percentile: 52th
Elmore County faces low composite natural disaster risk (NRI Risk Index score 52.0, 52th national percentile), driven primarily by wildfire and avalanche exposure. Expected annual loss across all 18 hazard types is $22M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
FEMA's National Risk Index rates Elmore County at low composite risk, with a National Risk Index score of 52.0 out of 100 — placing it in the 52nd national percentile and below the national average for natural-disaster risk. The score blends Expected Annual Loss, Social Vulnerability, and Community Resilience across all 18 FEMA hazard types.
The county's risk is driven primarily by wildfire (uncontrolled fires that spread across wildland and into communities) at High risk — $13M in expected annual loss and about 0.03 events per year; avalanche (fast-moving snow and debris sliding down steep mountain slopes) at High risk — $2M in expected annual loss and about 0.17 events per year; and landslide (downhill movement of rock, soil, and debris on unstable slopes) at Low risk — $20K in expected annual loss and about 0.89 events per year. Across all hazards, FEMA estimates $22M in expected annual loss for a population of 29K.
Beyond physical exposure, Elmore County has a very low social vulnerability rating (how susceptible the population is to harm) and a very low community resilience rating (its capacity to prepare for and recover from disasters). Both measures sit toward the lower end, indicating relatively modest population sensitivity.
The federal record bears this out: Elmore County has received 11 federal disaster declarations since 1964, including 3 for flood events and 3 for fire events. The most recent was Covid-19 Pandemic (biological), declared in April 2020.
Among 44 Idaho counties, Elmore County ranks #14 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Wildfire | High | 0.03 / yr | $13M |
| Avalanche | High | 0.17 / yr | $2M |
| Landslide | Low | 0.89 / yr | $20K |
| Winter Weather | Medium | 13.43 / yr | $163K |
| Heat Wave | Low | 2.59 / yr | $704K |
| Strong Wind | Low | 0.32 / yr | $688K |
| Earthquake | Very Low | 0.01 / yr | $218K |
| Volcanic Activity | Very Low | 0.00 / yr | $7 |
| Ice Storm | Low | 0.08 / yr | $42K |
| Riverine Flood | Very Low | 0.71 / yr | $5M |
| Lightning | Very Low | 21.68 / yr | $97K |
| Drought | Very Low | 52.06 / yr | $3K |
| Hail | Very Low | 0.21 / yr | $80K |
| Cold Wave | Very Low | 0.09 / yr | $140K |
| Tornado | Very Low | 0.19 / yr | $44K |
| Coastal Flood | Very Low | 0.00 / yr | $0 |
| Hurricane | Very Low | 0.00 / yr | $0 |
| Tsunami | Very Low | 0.00 / yr | $0 |
Disaster History
Elmore County has received 11 federal disaster declarations since 1964, most recently Covid-19 Pandemic in April 2020. Most frequent causes: Flood (3), Fire (3), Biological (2).
| Declared | Type | Disaster |
|---|---|---|
| April 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| August 2017 | Flood | Flooding, Landslides, and Mudslides |
| April 2017 | Flood | Severe Winter Storms and Flooding |
| August 2013 | Fire | Elk Fire |
| August 2012 | Fire | Trinity Ridge Fire |
| September 2005 | Hurricane | Hurricane Katrina |
| September 2000 | Fire | Wildfires |
| January 1997 | Severe Storm | Severe Storms, Flooding, Mud and Landslides |
| May 1977 | Drought | Drought |
Showing the 10 most recent of 11 declarations.
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Elmore County?
Elmore County has a composite FEMA National Risk Index score of 52.0 out of 100, placing it in the Low category and the 52th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Elmore County?
The three highest-rated hazards are Wildfire (High, $13M EAL), Avalanche (High, $2M EAL), Landslide (Low, $20K EAL). These account for most of the county's expected annual losses.
How does Elmore County compare to other Idaho counties?
Elmore County ranks #14 of 44 Idaho counties for overall natural disaster risk, with a low rating.
How many federally declared disasters has Elmore County had?
FEMA records 11 federal disaster declarations for Elmore County since 1964, most often 3 for flood events and 3 for fire events. The most recent was Covid-19 Pandemic, declared in April 2020.
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. Elmore County's $22M EAL is a statistical average, not a guarantee for any specific year or address.