Salt Lake County, Utah Natural Disaster Risk
FEMA National Risk Index assessment · UT
HighComposite Risk Score
National percentile: 99th
Salt Lake County faces high composite natural disaster risk (NRI Risk Index score 98.6, 99th national percentile), driven primarily by earthquake and avalanche exposure. Expected annual loss across all 18 hazard types is $622M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
Salt Lake County carries a high composite natural disaster risk, with a National Risk Index score of 98.6 out of 100 — placing it in the 99th national percentile and in the upper tier of natural-disaster risk nationally. The score blends Expected Annual Loss, Social Vulnerability, and Community Resilience across all 18 FEMA hazard types.
Risk here concentrates in earthquake (ground shaking from sudden movement along geologic faults) at High risk — $488M in expected annual loss and about 0.02 events per year; avalanche (fast-moving snow and debris sliding down steep mountain slopes) at Very High risk — $12M in expected annual loss and about 1.53 events per year; and winter weather (heavy snow, blizzards, and hazardous winter conditions) at Very High risk — $2M in expected annual loss and about 28.20 events per year. Across all hazards, FEMA estimates $622M in expected annual loss for a population of 1.19M.
Beyond physical exposure, Salt Lake County has a very low social vulnerability rating (how susceptible the population is to harm) and a high community resilience rating (its capacity to prepare for and recover from disasters). A less vulnerable population paired with strong resilience helps the community absorb and recover from events.
The county's disaster history tells the same story: Salt Lake County has received 12 federal disaster declarations since 1983, including 3 for fire events and 3 for flood events. The most recent was Parleys Canyon Fire (fire), declared in August 2021.
Among 29 Utah counties, Salt Lake County ranks #1 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Earthquake | High | 0.02 / yr | $488M |
| Avalanche | Very High | 1.53 / yr | $12M |
| Winter Weather | Very High | 28.20 / yr | $2M |
| Wildfire | High | 0.01 / yr | $25M |
| Lightning | High | 39.39 / yr | $3M |
| Heat Wave | Medium | 2.16 / yr | $6M |
| Riverine Flood | Medium | 1.14 / yr | $79M |
| Landslide | Low | 0.87 / yr | $53K |
| Volcanic Activity | Very Low | 0.00 / yr | $281 |
| Tornado | Medium | 0.05 / yr | $4M |
| Strong Wind | Medium | 1.29 / yr | $1M |
| Hail | Low | 0.27 / yr | $754K |
| Drought | Low | 48.75 / yr | $144K |
| Cold Wave | Low | 0.06 / yr | $696K |
| Ice Storm | Very Low | 0.01 / yr | $12K |
| Coastal Flood | Very Low | 0.00 / yr | $0 |
| Hurricane | Very Low | 0.00 / yr | $0 |
| Tsunami | Very Low | 0.00 / yr | $0 |
Disaster History
Salt Lake County has received 12 federal disaster declarations since 1983, most recently Parleys Canyon Fire in August 2021. Most frequent causes: Fire (3), Flood (3), Biological (2).
| Declared | Type | Disaster |
|---|---|---|
| August 2021 | Fire | Parleys Canyon Fire |
| January 2021 | Severe Storm | Straight-Line Winds |
| July 2020 | Earthquake | Earthquake and Aftershocks |
| April 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| June 2012 | Fire | Rose Crest Fire |
| August 2011 | Flood | Flooding |
| September 2010 | Fire | Machine Gun Fire |
| September 2005 | Coastal Storm | Hurricane Katrina Evacuation |
| August 1999 | Tornado | Tornado, Severe Thunderstorms, and Hail |
Showing the 10 most recent of 12 declarations.
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Salt Lake County?
Salt Lake County has a composite FEMA National Risk Index score of 98.6 out of 100, placing it in the High category and the 99th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Salt Lake County?
The three highest-rated hazards are Earthquake (High, $488M EAL), Avalanche (Very High, $12M EAL), Winter Weather (Very High, $2M EAL). These account for most of the county's expected annual losses.
How does Salt Lake County compare to other Utah counties?
Salt Lake County ranks #1 of 29 Utah counties for overall natural disaster risk, with a high rating.
How many federally declared disasters has Salt Lake County had?
FEMA records 12 federal disaster declarations for Salt Lake County since 1983, most often 3 for fire events and 3 for flood events. The most recent was Parleys Canyon Fire, declared in August 2021.
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. Salt Lake County's $622M EAL is a statistical average, not a guarantee for any specific year or address.