Is Onondaga County, NY in a flood zone?
FEMA's National Risk Index puts Onondaga County's flood hazard at the 95.2th percentile nationally — well above 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. County-wide, not parcel-specific: FEMA's real flood-zone map is queried live, never shipped as a download.
Who actually carries the flood insurance FEMA requires
Out of 2,978 homes FEMA counts inside Onondaga County's mapped flood zone, 820 carry the flood policy federal law requires there — 27.5% compliance, short of full coverage. Across all residential structures in Onondaga County, not just the ones FEMA mandates, 0.7% carry an NFIP policy — most flood damage nationally happens outside the mapped high-risk zone, so that broader number matters too.
How Onondaga County compares nationally
Onondaga County sits at rank 164 of 3144 counties on FEMA's flood hazard scale (1 is worst) and rank 157 of 3144 by population (1 is biggest). Onondaga County, New York is home to about 469,812 people across 778.393 square miles of land.
Checking a specific address in Onondaga County
FEMA counts 153,663 residential structures in Onondaga County overall, 1,056 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 Onondaga 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.