Is Clay County, SD in a flood zone?
FEMA's National Risk Index puts Clay County's flood hazard at the 28.7th percentile nationally — among the lowest flood hazard in the country — driven by inland rivers and flash flooding rather than the coast — FEMA's model puts a flood event here at about 2.1 times a year. This describes the county, not any one street — FEMA only publishes exact parcel zones through a live map service.
Clay County's flood-insurance compliance gap
0% of the homes FEMA requires to carry flood insurance in Clay County — those inside the mapped Special Flood Hazard Area — actually have a policy in force: 0 policies against 28 mandated structures, which means a meaningful share of legally-required coverage simply isn't there. Across all residential structures in Clay County, not just the ones FEMA mandates, 0.1% carry an NFIP policy — most flood damage nationally happens outside the mapped high-risk zone, so that broader number matters too.
How Clay County compares nationally
Clay County sits at rank 2293 of 3144 counties on FEMA's flood hazard scale (1 is worst) and rank 2078 of 3144 by population (1 is biggest). Clay County, South Dakota covers 412.022 square miles and counts roughly 15,245 residents.
What to do next if you own or are buying in Clay County
FEMA counts 6,253 residential structures in Clay County overall, 6 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 Clay 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.