Is Franklin County, ID in a flood zone?
FEMA's National Risk Index puts Franklin County's flood hazard at the 17.4th 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 4 years. This describes the county, not any one street — FEMA only publishes exact parcel zones through a live map service.
Mandatory flood insurance compliance in Franklin County
Franklin 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 Franklin County, not just the ones FEMA mandates, 0.1% carry an NFIP policy — most flood damage nationally happens outside the mapped high-risk zone, so that broader number matters too.
How Franklin County compares nationally
Franklin County sits at rank 2631 of 3144 counties on FEMA's flood hazard scale (1 is worst) and rank 2059 of 3144 by population (1 is biggest). About 15,638 people live in Franklin County, Idaho, spread over 663.019 square miles.
What to do next if you own or are buying in Franklin County
4 of Franklin County's 4,980 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 Franklin County's numbers. See the data quality guide for why Franklin County, like hundreds of other counties, doesn't get a clean compliance percentage.