Duchesne County, Utah Natural Disaster Risk
FEMA National Risk Index assessment · UT
Very LowComposite Risk Score
National percentile: 8th
Duchesne County faces very low composite natural disaster risk (NRI Risk Index score 7.6, 8th national percentile), driven primarily by landslide and lightning exposure. Expected annual loss across all 18 hazard types is $5M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
Overall natural disaster risk in Duchesne County is very low, with a National Risk Index score of 7.6 out of 100 — placing it in the 8th 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.
Most of Duchesne County's expected losses come from landslide (downhill movement of rock, soil, and debris on unstable slopes) at Medium risk — $75K in expected annual loss and about 2.88 events per year; lightning (electrical discharges from storms that ignite fires and cause casualties) at High risk — $1M in expected annual loss and about 48.91 events per year; and wildfire (uncontrolled fires that spread across wildland and into communities) at Low risk — $577K in expected annual loss and about 0.00 events per year. Across all hazards, FEMA estimates $5M in expected annual loss for a population of 20K.
Beyond physical exposure, Duchesne County has a very low social vulnerability rating (how susceptible the population is to harm) and a 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: Duchesne County has received 8 federal disaster declarations since 1977, including 2 for biological events and 2 for fire events. The most recent was Covid-19 Pandemic (biological), declared in April 2020.
Among 29 Utah counties, Duchesne County ranks #22 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Landslide | Medium | 2.88 / yr | $75K |
| Lightning | High | 48.91 / yr | $1M |
| Wildfire | Low | 0.00 / yr | $577K |
| Avalanche | Low | 0.30 / yr | $18K |
| Earthquake | Low | 0.01 / yr | $621K |
| Drought | Low | 97.27 / yr | $193K |
| Winter Weather | Low | 28.96 / yr | $86K |
| Volcanic Activity | Very Low | 0.00 / yr | $2 |
| Heat Wave | Very Low | 0.45 / yr | $93K |
| Riverine Flood | Very Low | 0.68 / yr | $3M |
| Ice Storm | Very Low | 0.01 / yr | $6K |
| Tornado | Very Low | 0.11 / yr | $47K |
| Strong Wind | Very Low | 0.27 / yr | $60K |
| Cold Wave | Very Low | 0.04 / yr | $36K |
| Hail | Very Low | 0.17 / yr | $14K |
| Coastal Flood | Very Low | 0.00 / yr | $0 |
| Hurricane | Very Low | 0.00 / yr | $0 |
| Tsunami | Very Low | 0.00 / yr | $0 |
Disaster History
Duchesne County has received 8 federal disaster declarations since 1977, most recently Covid-19 Pandemic in April 2020. Most frequent causes: Biological (2), Fire (2), Flood (2).
| Declared | Type | Disaster |
|---|---|---|
| April 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| July 2018 | Fire | Dollar Ridge Fire |
| August 2011 | Flood | Flooding |
| June 2007 | Fire | Neola North Fire |
| September 2005 | Coastal Storm | Hurricane Katrina Evacuation |
| April 1983 | Flood | Severe Storms, Landslides & Flooding |
| January 1977 | Drought | Drought |
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Duchesne County?
Duchesne County has a composite FEMA National Risk Index score of 7.6 out of 100, placing it in the Very Low category and the 8th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Duchesne County?
The three highest-rated hazards are Landslide (Medium, $75K EAL), Lightning (High, $1M EAL), Wildfire (Low, $577K EAL). These account for most of the county's expected annual losses.
How does Duchesne County compare to other Utah counties?
Duchesne County ranks #22 of 29 Utah counties for overall natural disaster risk, with a very low rating.
How many federally declared disasters has Duchesne County had?
FEMA records 8 federal disaster declarations for Duchesne County since 1977, most often 2 for biological events and 2 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. Duchesne County's $5M EAL is a statistical average, not a guarantee for any specific year or address.