Parts of New York City’s subway system also flooded. The U.S. Federal Emergency Management Agency’s flood maps are intended to be the nation’s primary tool for identifying flood risks.

While FEMA has improved the accuracy and accessibility of the maps over time with better data, digital tools and community input, the maps still don't capture everything.

The U.S. Federal Emergency Management Agency’s flood maps are intended to be the nation’s primary tool for identifying flood risks. Originally developed in the 1970s to support the National ...

advertisement 07-16-2025 IMPACT Why FEMA’s flood maps often miss dangerous flash flood risks There are areas of the country that flood, some regularly, that don’t show up on the maps as at risk.