Is Custer County, CO in a flood zone?
FEMA's National Risk Index puts Custer County's flood hazard at the 9.5th 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 1 years. That's a county-wide figure, not a per-address one — FEMA's parcel maps are a live lookup, not a bulk file.
Mandatory flood insurance compliance in Custer County
Custer 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 Custer 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 Custer County ranks
Custer County sits at rank 2862 of 3144 counties on FEMA's flood hazard scale (1 is worst) and rank 2775 of 3144 by population (1 is biggest). Custer County, Colorado covers 738.626 square miles and counts roughly 5,553 residents.
Checking a specific address in Custer County
Across all of Custer County's 4,137 residential structures, 0 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 Custer County's numbers. See the data quality guide for why Custer County, like hundreds of other counties, doesn't get a clean compliance percentage.