How much flood risk does Knox County actually carry?
Knox County lands at the 69.2th percentile of FEMA's National Risk Index for flooding, "Relatively Moderate" territory — a middling flood hazard by national standards — with the hazard driven by coastal storm surge rather than inland rivers — FEMA's model puts a surge event here at about 8.4 times a year. This describes the county, not any one street — FEMA only publishes exact parcel zones through a live map service.
Mandatory flood insurance compliance in Knox County
Homes with a federally backed mortgage inside Knox 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, 30.3% of them do — 151 active policies against 498 structures FEMA counts in that zone, leaving a real compliance gap. Across all residential structures in Knox County, not just the ones FEMA mandates, 1.5% carry an NFIP policy — most flood damage nationally happens outside the mapped high-risk zone, so that broader number matters too.
Knox County against the rest of the country
Knox County sits at rank 1008 of 3144 counties on FEMA's flood hazard scale (1 is worst) and rank 1173 of 3144 by population (1 is biggest). Knox County, Maine covers 364.902 square miles and counts roughly 40,981 residents.
Your street may differ from Knox County's average
FEMA counts 19,726 residential structures in Knox County overall, 304 of them carrying some form of NFIP coverage — but a lender or insurer cares about one parcel, not that county total.
More on how this number was built
The methodology guide shows exactly which FEMA and Census tables feed Knox County's numbers. Because storm surge plays a real role here, the guide to coastal vs. inland flood hazard is worth reading alongside this page.