How much flood risk does Sauk County actually carry?
Sauk County lands at the 77.5th percentile of FEMA's National Risk Index for flooding, "Relatively Moderate" territory — a middling flood hazard by national standards — with the hazard driven by inland rivers and flash flooding rather than the coast — FEMA's model puts a flood event here at about 1.8 times a year. That's a county-wide figure, not a per-address one — FEMA's parcel maps are a live lookup, not a bulk file.
Who actually carries the flood insurance FEMA requires
Out of 203 homes FEMA counts inside Sauk County's mapped flood zone, 79 carry the flood policy federal law requires there — 38.9% compliance, short of full coverage. Across all residential structures in Sauk County, not just the ones FEMA mandates, 0.5% carry an NFIP policy — most flood damage nationally happens outside the mapped high-risk zone, so that broader number matters too.
Where Sauk County ranks
Sauk County sits at rank 736 of 3144 counties on FEMA's flood hazard scale (1 is worst) and rank 822 of 3144 by population (1 is biggest). Sauk County, Wisconsin covers 831.587 square miles and counts roughly 66,486 residents.
What to do next if you own or are buying in Sauk County
Across all of Sauk County's 22,006 residential structures, 111 carry an NFIP policy today — a county-wide count that still can't tell you one address's own mapped zone.
More on how this number was built
The methodology guide shows exactly which FEMA and Census tables feed Sauk 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.