How much flood risk does Allendale County actually carry?
Allendale County lands at the 14.5th percentile of FEMA's National Risk Index for flooding, "Very Low" territory — among the lowest flood hazard in the country — with the hazard driven by inland rivers and flash flooding rather than the coast — FEMA's model puts a flood event here at about once every 7 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 Allendale County
Homes with a federally backed mortgage inside Allendale County's mapped high-risk flood zone (the Special Flood Hazard Area, or SFHA) are legally required to carry an NFIP flood policy. In practice, 8.7% of them do — 2 active policies against 23 structures FEMA counts in that zone, leaving a real compliance gap. Across all residential structures in Allendale 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.
Where Allendale County ranks
Allendale County sits at rank 2720 of 3144 counties on FEMA's flood hazard scale (1 is worst) and rank 2612 of 3144 by population (1 is biggest). Allendale County, South Carolina covers 408.095 square miles and counts roughly 7,551 residents.
Checking a specific address in Allendale County
FEMA counts 4,132 residential structures in Allendale County overall, 5 of them carrying some form of NFIP coverage — but a lender or insurer cares about one parcel, not that county total.
More on how this number was built
The methodology guide shows exactly which FEMA and Census tables feed Allendale County's numbers. The guide to what the Special Flood Hazard Area actually means explains why the mandatory-insurance rule exists and who it applies to.