Is Tompkins County, NY in a flood zone?
FEMA's National Risk Index puts Tompkins County's flood hazard at the 86.2th percentile nationally — a middling flood hazard by national standards — driven by inland rivers and flash flooding rather than the coast — FEMA's model puts a flood event here at about once every 1 years. 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
Tompkins 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 Tompkins 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.
How Tompkins County compares nationally
Tompkins County sits at rank 458 of 3144 counties on FEMA's flood hazard scale (1 is worst) and rank 595 of 3144 by population (1 is biggest). About 105,602 people live in Tompkins County, New York, spread over 474.65 square miles.
Your street may differ from Tompkins County's average
FEMA counts 29,641 residential structures in Tompkins County overall, 366 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 Tompkins County's numbers. See the data quality guide for why Tompkins County, like hundreds of other counties, doesn't get a clean compliance percentage.