How much flood risk does Polk County actually carry?
Polk County lands at the 57.9th 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 4 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
0.8% of the homes FEMA requires to carry flood insurance in Polk County — those inside the mapped Special Flood Hazard Area — actually have a policy in force: 1 policies against 121 mandated structures, which means a meaningful share of legally-required coverage simply isn't there. Across all residential structures in Polk County, not just the ones FEMA mandates, 0% carry an NFIP policy — most flood damage nationally happens outside the mapped high-risk zone, so that broader number matters too.
Where Polk County ranks
Polk County sits at rank 1386 of 3144 counties on FEMA's flood hazard scale (1 is worst) and rank 1366 of 3144 by population (1 is biggest). About 33,070 people live in Polk County, Missouri, spread over 635.527 square miles.
Your street may differ from Polk County's average
Across all of Polk County's 15,270 residential structures, 3 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 Polk 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.