How much flood risk does Bronx County actually carry?
Bronx County lands at the 98.5th percentile of FEMA's National Risk Index for flooding, "Relatively High" territory — well above the national norm for flood hazard — with the hazard driven by inland rivers and flash flooding rather than the coast — FEMA's model puts a flood event here at about 2 times a year. This describes the county, not any one street — FEMA only publishes exact parcel zones through a live map service.
Mandatory flood insurance compliance in Bronx County
Bronx 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 Bronx County, not just the ones FEMA mandates, 2.3% carry an NFIP policy — most flood damage nationally happens outside the mapped high-risk zone, so that broader number matters too.
Bronx County against the rest of the country
Bronx County sits at rank 54 of 3144 counties on FEMA's flood hazard scale (1 is worst) and rank 30 of 3144 by population (1 is biggest). Bronx County, New York is home to about 1,384,724 people across 42.201 square miles of land.
Your street may differ from Bronx County's average
1,844 of Bronx County's 81,517 residential structures carry flood coverage of some kind, per FEMA's latest count — useful context, not a substitute for checking one parcel.
More on how this number was built
The methodology guide shows exactly which FEMA and Census tables feed Bronx County's numbers. See the data quality guide for why Bronx County, like hundreds of other counties, doesn't get a clean compliance percentage.