How much flood risk does Williams County actually carry?
Williams County lands at the 42.9th 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 3 years. County-wide, not parcel-specific: FEMA's real flood-zone map is queried live, never shipped as a download.
Williams County's flood-insurance compliance gap
Williams 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 Williams County, not just the ones FEMA mandates, 0.3% carry an NFIP policy — most flood damage nationally happens outside the mapped high-risk zone, so that broader number matters too.
Williams County against the rest of the country
Williams County sits at rank 1856 of 3144 counties on FEMA's flood hazard scale (1 is worst) and rank 1177 of 3144 by population (1 is biggest). Williams County, North Dakota is home to about 40,763 people across 2,077.6 square miles of land.
What to do next if you own or are buying in Williams County
28 of Williams County's 11,108 residential structures carry flood coverage of some kind, per FEMA's latest count — useful context, not a substitute for checking one parcel.
More on how this number was built
The methodology guide shows exactly which FEMA and Census tables feed Williams County's numbers. See the data quality guide for why Williams County, like hundreds of other counties, doesn't get a clean compliance percentage.