Jefferson County, PA flood risk explained
Flood hazard in Jefferson County sits at the 74.5th national percentile, a middling flood hazard by national standards; driven by inland rivers and flash flooding rather than the coast — FEMA's model puts a flood event here at about 2 times a year. County-wide, not parcel-specific: FEMA's real flood-zone map is queried live, never shipped as a download.
Jefferson County's flood-insurance compliance gap
9.6% of the homes FEMA requires to carry flood insurance in Jefferson County — those inside the mapped Special Flood Hazard Area — actually have a policy in force: 89 policies against 928 mandated structures, which means a meaningful share of legally-required coverage simply isn't there. Looking beyond the mandated zone, 0.5% of all residential structures in Jefferson County carry flood coverage voluntarily or otherwise — relevant because most NFIP claims nationally come from outside the mapped SFHA.
Where Jefferson County ranks
Among the 3144 US counties FEMA scores for flood hazard, Jefferson County ranks 839 — 1 being the highest hazard nationally — and 1131 by population among all 3144 counties covered here, where 1 is the largest. About 43,367 people live in Jefferson County, Pennsylvania, spread over 652.44 square miles.
Checking a specific address in Jefferson County
Across all of Jefferson County's 26,007 residential structures, 117 carry an NFIP policy today — a county-wide count that still can't tell you one address's own mapped zone.
Where Jefferson 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.