Fairfax County Disaster Risk

Fairfax County has a FEMA National Risk Index rating of Relatively High, placing it in the 95th 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.

Fairfax County is evaluated for five major natural hazard types: flooding (97th percentile), hurricane (93th percentile), earthquake (93th percentile), tornado (54th percentile), wildfire (34th percentile). The highest-risk hazard is flooding at the 97th 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.

Fairfax County's composite risk percentile is 95th, compared to the Virginia state average of 33th percentile. The state's overall risk rating is Very Low. This means Fairfax County faces higher natural disaster risk than the typical county in Virginia.

Yes, Fairfax County's flooding risk is at the 97th 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.

Fairfax County's composite risk score of 95th percentile is above the Virginia state average of 33th percentile. This elevated risk is driven by flooding exposure (97th 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.