Is Fairfax County, VA in a flood zone?
FEMA's National Risk Index puts Fairfax County's flood hazard at the 97th percentile nationally — well above the national norm for flood hazard — driven by inland rivers and flash flooding rather than the coast — FEMA's model puts a flood event here at about 5.8 times a year. County-wide, not parcel-specific: FEMA's real flood-zone map is queried live, never shipped as a download.
Who actually carries the flood insurance FEMA requires
Out of 3,414 homes FEMA counts inside Fairfax County's mapped flood zone, 740 carry the flood policy federal law requires there — 21.7% compliance, short of full coverage. Across all residential structures in Fairfax County, not just the ones FEMA mandates, 1.1% carry an NFIP policy — most flood damage nationally happens outside the mapped high-risk zone, so that broader number matters too.
Fairfax County against the rest of the country
Fairfax County sits at rank 103 of 3144 counties on FEMA's flood hazard scale (1 is worst) and rank 42 of 3144 by population (1 is biggest). Fairfax County, Virginia covers 391.021 square miles and counts roughly 1,160,925 residents.
Your street may differ from Fairfax County's average
Across all of Fairfax County's 337,120 residential structures, 3,582 carry an NFIP policy today — a county-wide count that still can't tell you one address's own mapped zone.
More on how this number was built
The methodology guide shows exactly which FEMA and Census tables feed Fairfax County's numbers. The guide to what the Special Flood Hazard Area actually means explains why the mandatory-insurance rule exists and who it applies to.