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

Roberts County Disaster Risk

Roberts County, South Dakota

FEMA Risk Rating

Very Low

National Percentile

38th

of 3,144 counties

State Rank

#20

of 66 (1 = highest risk)

Flood Risk

38th

percentile

Hazard Risk Breakdown

Flood

River, coastal, and surface flooding risk

Very Low

Higher than 38% of US counties

Wildfire

Wildland and wildland-urban interface fire risk

Relatively Low

Higher than 74% of US counties

Tornado

Tornado and severe thunderstorm risk

Relatively Low

Higher than 50% of US counties

Earthquake

Seismic activity and ground shaking risk

Very Low

Higher than 9% of US counties

Risk Overview

About Natural Disaster Risk in Roberts County, South Dakota

Roberts County shows moderate-low risk

Roberts County scores 37.79 on the composite risk scale, placing it in the very low category but above South Dakota's average of 26.84. The county's overall exposure reflects moderate wildfire concern balanced against low tornado, flood, and earthquake threats.

Below-average risk for South Dakota

Roberts County ranks in the lower half of South Dakota's 66 counties for disaster exposure, with a composite risk of 37.79 that slightly exceeds the state average. The county's position reflects northeastern location with modest wildfire exposure but limited other hazard threats.

Higher risk than Potter County

Roberts County's composite risk of 37.79 exceeds nearby Potter County's 10.02 but remains substantially lower than western counties like Pennington (78.56). The difference reflects Roberts County's greater wildfire exposure while maintaining lower flood and earthquake risk than Black Hills regions.

Wildfire and tornado pose dual threat

Wildfire risk in Roberts County reaches 74.05, representing the primary hazard concern for the county's northeastern location. Tornado risk of 50.45 presents a secondary but meaningful threat, while flood and earthquake risks remain minimal below 10.

Emphasize wildfire and tornado coverage

Roberts County homeowners should ensure standard policies include wildfire and tornado coverage, as both hazards pose real threats to the region. Maintain 30 feet of defensible space around structures during dry seasons and keep a weather radio active during spring storm season for advance tornado warnings.

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

Preparedness Guide

What to Prepare for in Roberts County

Top Hazards by Exposure

  1. #1
    WildfirePrepare
    74th percentile
  2. #2
    TornadoPrepare
    50th percentile
  3. #3
    FloodPrepare
    38th percentile

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

Risk Advisory: Roberts County

Risk Verdict

Roberts County's natural disaster risk is among the lowest in the country, with a composite score at the 38th percentile nationally. At the 38th percentile nationally, Roberts County's natural hazard profile is comparatively favorable — community resilience is reinforced when individual households maintain a reviewed emergency plan.

Hazard Breakdown

Wildfire risk is Roberts County's dominant natural hazard, ranked at the 74th percentile nationally under FEMA's National Risk Index. Tornado ranks second at the 50th percentile nationally. Additional tracked hazards include flood (38th percentile), earthquake (9th percentile).

Preparedness Context

Wildfire is Roberts County's top-ranked natural hazard at the 74th percentile nationally. Roberts County residents should assess whether their property lies within or adjacent to a Wildland-Urban Interface (WUI) zone, where ember transport and rapid spread pose the highest risk. A secondary tornado exposure at the 50th percentile nationally means Roberts County residents face hazards from two distinct natural peril categories during different seasons. For Roberts County households, a practiced evacuation plan — with a primary and backup route designated before a fire occurs — provides more protection than any structural improvement when a wildfire approaches fast-moving terrain.

Regional Context

Roberts County's composite risk score sits 10.9 points above the South Dakota county average, placing it among the more hazard-exposed counties in the state.

Is your household prepared for Roberts 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 Roberts County, SD?
Roberts County has a FEMA National Risk Index rating of Very Low, placing it in the 38th 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 Roberts County?
Roberts County is evaluated for five major natural hazard types: wildfire (74th percentile), tornado (50th percentile), flooding (38th percentile), earthquake (9th percentile). The highest-risk hazard is wildfire at the 74th 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 Roberts County risk compare to the South Dakota average?
Roberts County's composite risk percentile is 38th, compared to the South Dakota state average of 27th percentile. The state's overall risk rating is Very Low. This means Roberts County faces higher natural disaster risk than the typical county in South Dakota.
Is Roberts County at risk for wildfire?
Yes, Roberts County's wildfire risk is at the 74th percentile nationally. This is above the national median. For flooding specifically, Roberts County is at the 38th 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.
Why is Roberts County higher risk than average?
Roberts County's composite risk score of 38th percentile is above the South Dakota state average of 27th percentile. This elevated risk is driven by wildfire exposure (74th percentile), along with tornado risk. Geographic location, terrain, climate patterns, and proximity to flood zones or fault lines all influence a county's risk profile.
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.