Is Douglas County, SD in a flood zone?
FEMA's National Risk Index puts Douglas County's flood hazard at the 10.5th 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 once every 2 years. That's a county-wide figure, not a per-address one — FEMA's parcel maps are a live lookup, not a bulk file.
Douglas County's flood-insurance compliance gap
Douglas County is one of the counties where FEMA's own denominator for mandated flood-zone structures is missing, so no compliance rate is shown rather than a guessed one — the data quality guide covers how common this is. Across all residential structures in Douglas County, not just the ones FEMA mandates, 0.2% carry an NFIP policy — most flood damage nationally happens outside the mapped high-risk zone, so that broader number matters too.
Where Douglas County ranks
Douglas County sits at rank 2833 of 3144 counties on FEMA's flood hazard scale (1 is worst) and rank 2966 of 3144 by population (1 is biggest). About 2,849 people live in Douglas County, South Dakota, spread over 431.801 square miles.
Checking a specific address in Douglas County
FEMA counts 2,749 residential structures in Douglas County overall, 4 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 Douglas County's numbers. See the data quality guide for why Douglas County, like hundreds of other counties, doesn't get a clean compliance percentage.