Williamsburg County Disaster Risk

Williamsburg County has a FEMA National Risk Index rating of Relatively Moderate, placing it in the 82th 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.

Williamsburg County is evaluated for five major natural hazard types: hurricane (95th percentile), earthquake (92th percentile), wildfire (87th percentile), flooding (60th percentile), tornado (44th percentile). The highest-risk hazard is hurricane at the 95th 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.

Williamsburg County's composite risk percentile is 82th, compared to the South Carolina state average of 71th percentile. The state's overall risk rating is Relatively Low. This means Williamsburg County faces higher natural disaster risk than the typical county in South Carolina.

Yes, Williamsburg County's hurricane risk is at the 95th percentile nationally. This places it in the top quartile for this hazard type. For flooding specifically, Williamsburg County is at the 60th percentile.

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.

Williamsburg County's composite risk score of 82th percentile is above the South Carolina state average of 71th percentile. This elevated risk is driven by hurricane exposure (95th percentile), along with earthquake and wildfire and flooding risk. Geographic location, terrain, climate patterns, and proximity to flood zones or fault lines all influence a county's risk profile.