Is Lyon County, NV in a flood zone?
FEMA's National Risk Index puts Lyon County's flood hazard at the 63.5th percentile nationally — below the national norm for flood hazard — driven by inland rivers and flash flooding rather than the coast — FEMA's model puts a flood event here at about 1 times a year. That's a county-wide figure, not a per-address one — FEMA's parcel maps are a live lookup, not a bulk file.
Who actually carries the flood insurance FEMA requires
Out of 1,414 homes FEMA counts inside Lyon County's mapped flood zone, 253 carry the flood policy federal law requires there — 17.9% compliance, short of full coverage. Across all residential structures in Lyon County, not just the ones FEMA mandates, 1.2% carry an NFIP policy — most flood damage nationally happens outside the mapped high-risk zone, so that broader number matters too.
Where Lyon County ranks
Lyon County sits at rank 1199 of 3144 counties on FEMA's flood hazard scale (1 is worst) and rank 856 of 3144 by population (1 is biggest). About 63,718 people live in Lyon County, Nevada, spread over 2,003.054 square miles.
Your street may differ from Lyon County's average
Across all of Lyon County's 27,168 residential structures, 325 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 Lyon 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.