Jefferson County, PA Flood Zone & Flood Risk Data
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 twice 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.