How much flood risk does Pierce County actually carry?
Pierce County lands at the 96.2th percentile of FEMA's National Risk Index for flooding, "Relatively High" territory — well above the national norm for flood hazard — with the hazard driven by inland rivers and flash flooding rather than the coast — FEMA's model puts a flood event here at about once every 9 years. County-wide, not parcel-specific: FEMA's real flood-zone map is queried live, never shipped as a download.
Mandatory flood insurance compliance in Pierce County
Homes with a federally backed mortgage inside Pierce County's mapped high-risk flood zone (the Special Flood Hazard Area, or SFHA) are legally required to carry an NFIP flood policy. In practice, 43.7% of them do — 1,250 active policies against 2,861 structures FEMA counts in that zone, leaving a real compliance gap. Across all residential structures in Pierce County, not just the ones FEMA mandates, 0.7% carry an NFIP policy — most flood damage nationally happens outside the mapped high-risk zone, so that broader number matters too.
Pierce County against the rest of the country
Pierce County sits at rank 127 of 3144 counties on FEMA's flood hazard scale (1 is worst) and rank 60 of 3144 by population (1 is biggest). Pierce County, Washington covers 1,668.025 square miles and counts roughly 941,170 residents.
What to do next if you own or are buying in Pierce County
Across all of Pierce County's 292,228 residential structures, 2,101 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 Pierce 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.