Butte County, Idaho Natural Disaster Risk
FEMA National Risk Index assessment · ID
Very LowComposite Risk Score
National percentile: 4th
Butte County faces very low composite natural disaster risk (NRI Risk Index score 4.4, 4th national percentile), driven primarily by avalanche and volcanic activity exposure. Expected annual loss across all 18 hazard types is $3M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
Butte County carries a very low composite natural disaster risk, with a National Risk Index score of 4.4 out of 100 — placing it in the 4th national percentile and among the lowest-risk counties in the country. 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 avalanche (fast-moving snow and debris sliding down steep mountain slopes) at Medium risk — $457K in expected annual loss and about 0.03 events per year; volcanic activity (eruptions producing ashfall, lava, and pyroclastic hazards) at Very Low risk — $21 in expected annual loss and about 0.00 events per year; and wildfire (uncontrolled fires that spread across wildland and into communities) at Very Low risk — $60K in expected annual loss and about 0.00 events per year. Across all hazards, FEMA estimates $3M in expected annual loss for a population of 3K.
Beyond physical exposure, Butte County has a medium 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.
History supports the rating: Butte County has received 6 federal disaster declarations since 1964, including 2 for biological events and 1 for hurricane events. The most recent was Covid-19 Pandemic (biological), declared in April 2020.
Among 44 Idaho counties, Butte County ranks #41 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Avalanche | Medium | 0.03 / yr | $457K |
| Volcanic Activity | Very Low | 0.00 / yr | $21 |
| Wildfire | Very Low | 0.00 / yr | $60K |
| Landslide | Very Low | 0.42 / yr | $2K |
| Earthquake | Very Low | 0.01 / yr | $207K |
| Cold Wave | Low | 2.07 / yr | $610K |
| Winter Weather | Low | 12.70 / yr | $32K |
| Heat Wave | Very Low | 1.06 / yr | $110K |
| Drought | Very Low | 93.39 / yr | $2K |
| Riverine Flood | Very Low | 0.39 / yr | $1M |
| Strong Wind | Very Low | 0.76 / yr | $51K |
| Lightning | Very Low | 27.23 / yr | $15K |
| Ice Storm | Very Low | 0.01 / yr | $1K |
| Tornado | Very Low | 0.23 / yr | $7K |
| Hail | Very Low | 0.24 / yr | $4K |
| Coastal Flood | Very Low | 0.00 / yr | $0 |
| Hurricane | Very Low | 0.00 / yr | $0 |
| Tsunami | Very Low | 0.00 / yr | $0 |
Disaster History
Butte County has received 6 federal disaster declarations since 1964, most recently Covid-19 Pandemic in April 2020. Most frequent causes: Biological (2), Hurricane (1), Severe Storm (1).
| Declared | Type | Disaster |
|---|---|---|
| April 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| September 2005 | Hurricane | Hurricane Katrina |
| June 1997 | Severe Storm | Severe Storms, Snowmelt, Land/Mud Slides, Flooding |
| November 1983 | Earthquake | Earthquake |
| December 1964 | Flood | Heavy Rains & Flooding |
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Butte County?
Butte County has a composite FEMA National Risk Index score of 4.4 out of 100, placing it in the Very Low category and the 4th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Butte County?
The three highest-rated hazards are Avalanche (Medium, $457K EAL), Volcanic Activity (Very Low, $21 EAL), Wildfire (Very Low, $60K EAL). These account for most of the county's expected annual losses.
How does Butte County compare to other Idaho counties?
Butte County ranks #41 of 44 Idaho counties for overall natural disaster risk, with a very low rating.
How many federally declared disasters has Butte County had?
FEMA records 6 federal disaster declarations for Butte County since 1964, most often 2 for biological events and 1 for hurricane 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. Butte County's $3M EAL is a statistical average, not a guarantee for any specific year or address.