How much flood risk does Marion County actually carry?
Marion County lands at the 61.4th percentile of FEMA's National Risk Index for flooding, "Relatively Low" territory — below 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 1 years. That's a county-wide figure, not a per-address one — FEMA's parcel maps are a live lookup, not a bulk file.
Marion County's flood-insurance compliance gap
Homes with a federally backed mortgage inside Marion 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, 15.7% of them do — 71 active policies against 453 structures FEMA counts in that zone, leaving a real compliance gap. Across all residential structures in Marion 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.
How Marion County compares nationally
Marion County sits at rank 1270 of 3144 counties on FEMA's flood hazard scale (1 is worst) and rank 1448 of 3144 by population (1 is biggest). Marion County, Tennessee covers 498.254 square miles and counts roughly 29,826 residents.
Checking a specific address in Marion County
FEMA counts 13,325 residential structures in Marion County overall, 91 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 Marion 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.