Homeowners who don’t live near a federally recognized floodplain
may still be at risk of flooding, and the Federal Emergency Management Agency severely underestimates the number of people who could potentially be affected, according to a new study in the journal
Environmental Research Letters.
Researchers from the University of Bristol in the United Kingdom, the Nature Conservancy, and the Environmental Protection Agency say that the
U.S. population exposed to serious flooding could be more than triple previous estimates. They put the estimate at nearly 41 million Americans—compared to only 13 million when calculated using FEMA flood maps. “We find that population and GDP growth alone are expected to lead to significant future increases in exposure, and this change may be exacerbated in the future by climate change,” the researchers write.
Over the past 30 years, freshwater flooding has led to an average of $8.2 billion in damage each year. FEMA produces maps that show current coastal flood hazard areas in the U.S., but those maps are of varying age and quality, researchers note. The researchers’ estimates of current and future flood exposure are based on high-resolution hazard, population, asset, and projected development maps of the entire country.
The study’s findings come as the
National Flood Insurance Program is set to expire on March 23, putting some homeowners’ flood insurance policies at risk. The National Association of REALTORS® is advocating for a long-term extension of the NFIP, which provides flood insurance policies to 5 million property owners nationwide.
NAR sent a letter to senators last week, urging Congress to avoid a temporary shutdown of the NFIP. The program was allowed to lapse for two months in the past, costing more than 40,000 home sales, according to NAR research. The NFIP was extended 11 times between 2010 and 2012.
Source: “Estimates of Present and Future Flood Risk in the Conterminous United States,” Environmental Research Letters (Feb. 28, 2018)