Prince William County Disaster Risk

Prince William County has a FEMA National Risk Index rating of Relatively Moderate, placing it in the 83th 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.

Prince William County is evaluated for five major natural hazard types: flooding (88th percentile), hurricane (83th percentile), earthquake (81th percentile), tornado (77th percentile), wildfire (18th percentile). The highest-risk hazard is flooding at the 88th 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.

Prince William County's composite risk percentile is 83th, compared to the Virginia state average of 33th percentile. The state's overall risk rating is Very Low. This means Prince William County faces higher natural disaster risk than the typical county in Virginia.

Yes, Prince William County's flooding risk is at the 88th percentile nationally. This places it in the top quartile for this hazard type.

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.

Prince William County's composite risk score of 83th percentile is above the Virginia state average of 33th percentile. This elevated risk is driven by flooding exposure (88th percentile), along with hurricane and earthquake and tornado risk. Geographic location, terrain, climate patterns, and proximity to flood zones or fault lines all influence a county's risk profile.