How much flood risk does Kauai County actually carry?
Kauai County lands at the 90.6th percentile of FEMA's National Risk Index for flooding, "Relatively Moderate" territory — a middling flood hazard by national standards — with the hazard driven by inland rivers and flash flooding rather than the coast — FEMA's model puts a flood event here at about 5.8 times a year. County-wide, not parcel-specific: FEMA's real flood-zone map is queried live, never shipped as a download.
Mandatory flood insurance compliance in Kauai County
Kauai County is one of the counties where FEMA's own denominator for mandated flood-zone structures is missing, so no compliance rate is shown rather than a guessed one — the data quality guide covers how common this is. Across all residential structures in Kauai County, not just the ones FEMA mandates, 7% carry an NFIP policy — most flood damage nationally happens outside the mapped high-risk zone, so that broader number matters too.
Where Kauai County ranks
Kauai County sits at rank 315 of 3144 counties on FEMA's flood hazard scale (1 is worst) and rank 760 of 3144 by population (1 is biggest). About 73,840 people live in Kauai County, Hawaii, spread over 619.84 square miles.
Your street may differ from Kauai County's average
Across all of Kauai County's 23,490 residential structures, 1,647 carry an NFIP policy today — a county-wide count that still can't tell you one address's own mapped zone.
More on how this number was built
The methodology guide shows exactly which FEMA and Census tables feed Kauai County's numbers. See the data quality guide for why Kauai County, like hundreds of other counties, doesn't get a clean compliance percentage.