Davison County, South Dakota Natural Disaster Risk
FEMA National Risk Index assessment · SD
Very LowComposite Risk Score
National percentile: 39th
Davison County faces very low composite natural disaster risk (NRI Risk Index score 39.2, 39th national percentile), driven primarily by winter weather and ice storm exposure. Expected annual loss across all 18 hazard types is $13M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
Davison County carries a very low composite natural disaster risk, with a National Risk Index score of 39.2 out of 100 — placing it in the 39th 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 winter weather (heavy snow, blizzards, and hazardous winter conditions) at High risk — $366K in expected annual loss and about 15.84 events per year; ice storm (freezing rain that coats surfaces in heavy, damaging ice) at Medium risk — $458K in expected annual loss and about 0.66 events per year; and tornado (violently rotating columns of air capable of catastrophic local damage) at Medium risk — $3M in expected annual loss and about 0.26 events per year. Across all hazards, FEMA estimates $13M in expected annual loss for a population of 20K.
Beyond physical exposure, Davison County has a low social vulnerability rating (how susceptible the population is to harm) and a very 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 federal record bears this out: Davison County has received 15 federal disaster declarations since 1976, including 5 for flood events and 5 for severe storm events. The most recent was Severe Storms, Straight-Line Winds, and Flooding (flood), declared in August 2024.
Among 66 South Dakota counties, Davison County ranks #18 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Winter Weather | High | 15.84 / yr | $366K |
| Ice Storm | Medium | 0.66 / yr | $458K |
| Tornado | Medium | 0.26 / yr | $3M |
| Wildfire | Low | 0.00 / yr | $169K |
| Cold Wave | Medium | 7.74 / yr | $2M |
| Drought | Medium | 15.49 / yr | $457K |
| Hail | Low | 5.15 / yr | $519K |
| Strong Wind | Medium | 3.19 / yr | $900K |
| Riverine Flood | Low | 3.14 / yr | $5M |
| Lightning | Low | 36.13 / yr | $112K |
| Earthquake | Very Low | 0.00 / yr | $69K |
| Landslide | Very Low | 0.05 / yr | $257 |
| Heat Wave | Very Low | 6.05 / yr | $110K |
| Avalanche | Very Low | 0.00 / yr | $0 |
| Coastal Flood | Very Low | 0.00 / yr | $0 |
| Hurricane | Very Low | 0.00 / yr | $0 |
| Tsunami | Very Low | 0.00 / yr | $0 |
| Volcanic Activity | Very Low | 0.00 / yr | $0 |
Disaster History
Davison County has received 15 federal disaster declarations since 1976, most recently Severe Storms, Straight-Line Winds, and Flooding in August 2024. Most frequent causes: Flood (5), Severe Storm (5), Biological (2).
| Declared | Type | Disaster |
|---|---|---|
| August 2024 | Flood | Severe Storms, Straight-Line Winds, and Flooding |
| April 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| November 2019 | Severe Storm | Severe Storms, Tornadoes, and Flooding |
| June 2019 | Flood | Severe Winter Storm, Snowstorm, and Flooding |
| May 2007 | Severe Storm | Severe Storms, Tornadoes, and Flooding |
| December 2005 | Severe Storm | Severe Winter Storm |
| September 2005 | Coastal Storm | Hurricane Katrina Evacuation |
| April 1997 | Flood | Severe Flooding, Sever Winter Storms,Heavy Rains High Winds |
| January 1997 | Severe Storm | Severe Winter Storms and Blizzard Conditions |
Showing the 10 most recent of 15 declarations.
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Davison County?
Davison County has a composite FEMA National Risk Index score of 39.2 out of 100, placing it in the Very Low category and the 39th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Davison County?
The three highest-rated hazards are Winter Weather (High, $366K EAL), Ice Storm (Medium, $458K EAL), Tornado (Medium, $3M EAL). These account for most of the county's expected annual losses.
How does Davison County compare to other South Dakota counties?
Davison County ranks #18 of 66 South Dakota counties for overall natural disaster risk, with a very low rating.
How many federally declared disasters has Davison County had?
FEMA records 15 federal disaster declarations for Davison County since 1976, most often 5 for flood events and 5 for severe storm events. The most recent was Severe Storms, Straight-Line Winds, and Flooding, declared in August 2024.
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. Davison County's $13M EAL is a statistical average, not a guarantee for any specific year or address.