Brule County, South Dakota Natural Disaster Risk
FEMA National Risk Index assessment · SD
LowComposite Risk Score
National percentile: 59th
Brule County faces low composite natural disaster risk (NRI Risk Index score 58.7, 59th national percentile), driven primarily by cold wave and wildfire exposure. Expected annual loss across all 18 hazard types is $19M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
FEMA's National Risk Index rates Brule County at low composite risk, with a National Risk Index score of 58.7 out of 100 — placing it in the 59th 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.
Risk here concentrates in cold wave (prolonged spells of dangerously low temperatures) at High risk — $14M in expected annual loss and about 6.47 events per year; wildfire (uncontrolled fires that spread across wildland and into communities) at Low risk — $216K in expected annual loss and about 0.00 events per year; and drought (extended dry periods that stress water supplies and agriculture) at Medium risk — $590K in expected annual loss and about 25.58 events per year. Across all hazards, FEMA estimates $19M in expected annual loss for a population of 5K.
Beyond physical exposure, Brule County has a medium 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.
History supports the rating: Brule County has received 21 federal disaster declarations since 1976, including 8 for severe storm events and 7 for flood events. The most recent was Severe Storms, Straight-Line Winds, and Flooding (flood), declared in August 2024.
Among 66 South Dakota counties, Brule County ranks #8 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Cold Wave | High | 6.47 / yr | $14M |
| Wildfire | Low | 0.00 / yr | $216K |
| Drought | Medium | 25.58 / yr | $590K |
| Winter Weather | Medium | 15.53 / yr | $134K |
| Hail | Low | 4.27 / yr | $444K |
| Ice Storm | Medium | 0.32 / yr | $147K |
| Tornado | Low | 0.35 / yr | $637K |
| Riverine Flood | Very Low | 0.89 / yr | $3M |
| Strong Wind | Low | 2.70 / yr | $226K |
| Earthquake | Very Low | 0.00 / yr | $26K |
| Heat Wave | Very Low | 5.79 / yr | $33K |
| Landslide | Very Low | 0.11 / yr | $34 |
| Lightning | Very Low | 36.48 / yr | $34K |
| 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
Brule County has received 21 federal disaster declarations since 1976, most recently Severe Storms, Straight-Line Winds, and Flooding in August 2024. Most frequent causes: Severe Storm (8), Flood (7), 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 |
| September 2019 | Flood | Severe Storms and Flooding |
| June 2019 | Flood | Severe Winter Storm, Snowstorm, and Flooding |
| July 2015 | Severe Storm | Severe Storms, Tornadoes, Straight-Line Winds, and Flooding |
| May 2011 | Flood | Flooding |
| September 2010 | Severe Storm | Severe Storms and Flooding |
| May 2010 | Flood | Flooding |
Showing the 10 most recent of 21 declarations.
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Brule County?
Brule County has a composite FEMA National Risk Index score of 58.7 out of 100, placing it in the Low category and the 59th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Brule County?
The three highest-rated hazards are Cold Wave (High, $14M EAL), Wildfire (Low, $216K EAL), Drought (Medium, $590K EAL). These account for most of the county's expected annual losses.
How does Brule County compare to other South Dakota counties?
Brule County ranks #8 of 66 South Dakota counties for overall natural disaster risk, with a low rating.
How many federally declared disasters has Brule County had?
FEMA records 21 federal disaster declarations for Brule County since 1976, most often 8 for severe storm events and 7 for flood 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. Brule County's $19M EAL is a statistical average, not a guarantee for any specific year or address.