Butler County, PA: flood risk, in FEMA's own numbers
On FEMA's National Risk Index, Butler County scores at the 89th percentile for flood hazard, rated "Relatively Moderate" — a middling flood hazard by national standards. The hazard here is driven by inland rivers and flash flooding rather than the coast — FEMA's model puts a flood event here at about 2.5 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.
Butler County's flood-insurance compliance gap
Out of 1,173 homes FEMA counts inside Butler County's mapped flood zone, 237 carry the flood policy federal law requires there — 20.2% compliance, short of full coverage. Looking beyond the mandated zone, 0.5% of all residential structures in Butler County carry flood coverage voluntarily or otherwise — relevant because most NFIP claims nationally come from outside the mapped SFHA.
Butler County against the rest of the country
Among the 3144 US counties FEMA scores for flood hazard, Butler County ranks 362 — 1 being the highest hazard nationally — and 358 by population among all 3144 counties covered here, where 1 is the largest. Butler County, Pennsylvania covers 789.482 square miles and counts roughly 199,341 residents.
Your street may differ from Butler County's average
Across all of Butler County's 71,622 residential structures, 326 carry an NFIP policy today — a county-wide count that still can't tell you one address's own mapped zone.
Where Butler County's figures come from
Every figure on this page traces to a named FEMA dataset, documented in the methodology guide. If you're unsure why any of this insurance requirement exists at all, the SFHA explainer covers it from first principles.