New Study Shows Flooding Risks Higher Than Previously Thought

The number of buildings threatened by flooding in the U.S. could be higher than previously thought, according to a study published Monday.

The study focused on North Carolina and found 43% of flooded buildings in the state between 1996 and 2020 were located outside the Federal Emergency Management Agency’s (FEMA) Special Flood Hazard Area. The agency predicts Special Flood Hazard Areas have a 1% risk of flooding each year, and flood insurance is mandatory for buildings in these areas.

The researchers said the study shows the value of simulating flood events beyond those that generate the most damage and get the most attention from governments, media, and researchers. A database of flood maps also can be used to better understand how flood exposure, vulnerability, and risk change over time, the researchers said.

Experts told NBC News that with access to the right data sources, databases like the one described in the study could be developed nationwide. Currently, FEMA’s maps are the main source nationally to identify flood-prone areas and buildings that need to be insured.