Deadly and destructive flash flooding in Texas and several other states in July 2025 is raising questions about the nation’s flood maps and their ability to ensure that communities and homeowners can prepare for rising risks.

The same region of Texas Hill Country where a flash flood on July 4 killed more than 130 people was hit again with downpours a week later, forcing searchers to temporarily pause their efforts to find missing victims. Other states, including New Mexico, Oklahoma, Vermont, and Iowa, also saw flash flood damage in July.

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 Flood Insurance Program, these maps, known as Flood Insurance Rate Maps, or FIRMs, are used to determine where flood insurance is required for federally backed mortgages, to inform local building codes and land-use decisions, and to guide flood plain management strategies.

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 while FEMA has

© Fast Company