riskbycounty
FEMA NRI 1.19.0Updated Nov 2023 · Coverage 2014–2023Methodology

Grant County Disaster Risk

Grant County, South Dakota

FEMA Risk Rating

Very Low

National Percentile

19th

of 3,144 counties

State Rank

#34

of 66 (1 = highest risk)

Flood Risk

17th

percentile

Hazard Risk Breakdown

Flood

River, coastal, and surface flooding risk

Very Low

Higher than 17% of US counties

Wildfire

Wildland and wildland-urban interface fire risk

Relatively Low

Higher than 55% of US counties

Tornado

Tornado and severe thunderstorm risk

Very Low

Higher than 35% of US counties

Earthquake

Seismic activity and ground shaking risk

Very Low

Higher than 6% of US counties

Risk Overview

About Natural Disaster Risk in Grant County, South Dakota

Grant County's risk sits well below national average

With a composite risk score of 18.89, Grant County ranks as Very Low risk—substantially safer than the national average. This score reflects relatively modest exposure to most natural hazards across the county's landscape.

Grant County ranks safer than most South Dakota counties

Grant County's 18.89 score places it well below South Dakota's state average of 26.84, indicating below-average natural disaster risk for the region. The county faces fewer compounded hazard pressures than many of its neighbors across the state.

Among the region's safer counties

Grant County's risk profile is comparable to nearby Hamlin County (9.99) and Hand County (6.46), though moderately higher than Harding County's exceptionally low 1.49 score. These neighboring counties share Grant's pattern of very low overall risk.

Wildfire and tornado pose greatest threats

Wildfire risk registers at 54.61 and tornado risk at 34.61—the two hazards Grant County residents should monitor most closely. Flood risk (17.33) and earthquake risk (6.33) present minimal concern by comparison.

Prioritize wildfire and storm coverage

Grant County residents should ensure homeowners policies cover wildfire damage and maintain adequate tornado/wind protection given the county's moderate exposure to these hazards. Standard flood insurance isn't critical, but reviewing your policy's wildfire clauses is essential.

Source: FEMA National Risk Index · Narrative reviewed by Evan Brooks, Data Editor

Preparedness Guide

What to Prepare for in Grant County

Top Hazards by Exposure

  1. #1
    WildfirePrepare
    55th percentile
  2. #2
    TornadoPrepare
    35th percentile
  3. #3
    FloodPrepare
    17th percentile

Source: FEMA National Risk Index v1.19.0 · Percentiles are national (3,144 counties)

Risk Advisory: Grant County

Risk Verdict

Grant County carries a low natural disaster risk burden, scoring at the 19th percentile under the FEMA National Risk Index. The 19th percentile national ranking is one lens; Grant County residents also benefit from reviewing which specific hazard types drive the county's composite score and preparing accordingly.

Hazard Breakdown

Wildfire risk is Grant County's dominant natural hazard, ranked at the 55th percentile nationally under FEMA's National Risk Index. Tornado ranks second at the 35th percentile nationally. Additional tracked hazards include flood (17th percentile), earthquake (6th percentile).

Preparedness Context

Wildfire ranks as Grant County's primary hazard at the 55th percentile nationally. For Grant County households in high-WUI areas, go-bag readiness — the ability to leave within 15 minutes — is more important than shelter-in-place planning for most residential properties. The county's tornado exposure at the 35th percentile nationally complements the wildfire risk — saturating rain after burn scarring often triggers secondary flood and debris flow events. Grant County county's local emergency management office publishes community-specific wildfire risk assessments and evacuation zone maps; households should review their zone assignment and sign up for zone-specific alerts.

Regional Context

Compared to the South Dakota county average, Grant County's composite score runs 7.9 points lower — a gap that reflects the county's relatively modest hazard profile within its state context.

Is your household prepared for Grant County's hazards?

Review FEMA's county-specific preparedness checklists and emergency planning guides.

FEMA Ready Guide →

Frequently Asked Questions

What is the natural disaster risk in Grant County, SD?
Grant County has a FEMA National Risk Index rating of Very Low, placing it in the 19th percentile nationally out of 3,144 counties. This composite score reflects the county's overall exposure to natural hazards including floods, wildfires, tornadoes, earthquakes, and hurricanes, weighted by expected annual loss and social vulnerability.
What types of natural hazards affect Grant County?
Grant County is evaluated for five major natural hazard types: wildfire (55th percentile), tornado (35th percentile), flooding (17th percentile), earthquake (6th percentile). The highest-risk hazard is wildfire at the 55th percentile nationally. These scores are derived from FEMA's National Risk Index, which analyzes expected annual loss, social vulnerability, and community resilience for each hazard type.
How does Grant County risk compare to the South Dakota average?
Grant County's composite risk percentile is 19th, compared to the South Dakota state average of 27th percentile. The state's overall risk rating is Very Low. This means Grant County faces lower natural disaster risk than the typical county in South Dakota.
Is Grant County at risk for wildfire?
Yes, Grant County's wildfire risk is at the 55th percentile nationally. This is above the national median. For flooding specifically, Grant County is at the 17th percentile.
How is natural disaster risk measured?
FEMA's National Risk Index (NRI) calculates risk scores for 18 natural hazard types across all U.S. counties and census tracts. The composite score combines Expected Annual Loss (estimated dollar losses from each hazard), Social Vulnerability (demographic factors affecting disaster impact), and Community Resilience (ability to recover). Percentile scores rank each county against all 3,144 U.S. counties, and risk ratings range from Very Low to Very High.
Is Grant County a safe place to live?
Grant County's composite risk score of 19th percentile is below the South Dakota state average of 27th percentile, indicating relatively lower exposure to natural hazards. However, no county is completely risk-free. The primary hazard type is wildfire at the 55th percentile. Residents should still maintain emergency preparedness plans and appropriate insurance coverage.
By Evan Brooks, Data EditorUpdated Reviewed by Evan Brooks, Data Editor

Data Source

Risk data sourced from the FEMA National Risk Index (NRI). Risk scores are relative rankings (0–100) across all US counties — not absolute risk measures. Higher scores indicate higher relative risk compared to other counties.

Disclaimer: This data is informational only. It is not financial, insurance, or legal advice. Always consult a qualified professional before making insurance or real estate decisions.