York County, SC: flood risk, in FEMA's own numbers
On FEMA's National Risk Index, York County scores at the 90.2th 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 1.1 times a year. This describes the county, not any one street — FEMA only publishes exact parcel zones through a live map service.
York County's flood-insurance compliance gap
Out of 273 homes FEMA counts inside York County's mapped flood zone, 131 carry the flood policy federal law requires there — 48% compliance, short of full coverage. Looking beyond the mandated zone, 0.4% of all residential structures in York County carry flood coverage voluntarily or otherwise — relevant because most NFIP claims nationally come from outside the mapped SFHA.
Where York County ranks
Among the 3144 US counties FEMA scores for flood hazard, York County ranks 326 — 1 being the highest hazard nationally — and 242 by population among all 3144 counties covered here, where 1 is the largest. York County, South Carolina covers 680.607 square miles and counts roughly 303,001 residents.
Your street may differ from York County's average
Across all of York County's 91,615 residential structures, 383 carry an NFIP policy today — a county-wide count that still can't tell you one address's own mapped zone.
Where York 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.