In theory, the maps enable homeowners, businesses and local officials to understand their flood risk and take appropriate steps to prepare and mitigate potential losses. But there are areas of the ...

Using their own data, the group discovered more than 4,500 homes were actually in danger. Even when FEMA does mark the most dangerous flood areas, though, those warnings are not always heeded.

FEMA's maps are essential tools for identifying flood risks, but they have significant gaps that limit their effectiveness. One major limitation is that they don't consider flooding driven by ...

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.

“When I look at the flood map in the area of Camp Mystic, there is a small water course that comes in right there that doesn’t have good flood mapping data,” he says. “The action is simple.

I study flood-risk mapping as a university-based researcher and at First Street, an organization created to quantify and communicate climate risk. In a 2023 assessment using newly modeled flood ...