A new study by the First Street Foundation reports that flood risk maps by the Federal Emergency Management Agency (FEMA) significantly underestimates the risk of flooding in most counties in the United States. Part of the problem with the FEMA maps is keeping the maps up to date, which is not only costly and labor intensive, but further complicated as climate change has worsened the dangers. In addition, FEMA’s maps aren’t designed to account for flooding caused by intense rainfall, a growing problem as the atmosphere warms.
is a free online tool created by the nonprofit First Street Foundation
that makes it easy for Americans to finally find their property’s current and future risk of flooding, learn if it has flooded in the past, and understand how flood risks are changing because of the environment. First Street said that in some areas, their model may overestimate flood risk because it doesn’t capture every local flood-protection measure, such as pumps or catchment basins.
The model calculates any location’s probability of flooding from the four major flood types: rain, riverine, tidal events, and storm surge.
FEMA said it welcomed First Street’s initiative, saying it would “complement FEMA’s efforts.” “We know there is no perfect science to predict flooding,” a spokeswoman said. “The Flood Factor product may help property owners with the critical decisions they must make and purchase necessary insurance.”