Rising seas have created an unprecedented flood risk that could have severe economic impacts. And with federal data far underestimating the scope of flood risk on properties in the U.S., it could put homeowners in a precarious position, particularly those already living in regions prone to flooding. A new project from Realtor.com will provide more granular detail for millions of homes across the U.S. on flood risk.
Back in June, the nonprofit First Street Foundation released data that found the Federal Emergency Management Agency (FEMA) vastly understates the number of properties in the U.S. at substantial risk of flooding. While FEMA estimates that 8.7 million properties in the U.S. meet this criteria, First Street’s data found the number of substantially at-risk properties to be closer to 14.6 million. At the time, the foundation released a tool to check the “flood factor” on more than 142 million homes and properties in the continental U.S. Now, Realtor.com is including the foundation’s data on both for-sale and off-the-market listings on its website.
Listings will now show a flood risk score of between 1 and 10 from First Street in addition to flood zone information from FEMA, the company announced Wednesday. When pulling up a property listing on Realtor.com, the site now prominently displays the flood risk data directly below the property’s square footage and home information. That makes flood risk information on homes, which may not have been available to homeowners at all before, widely accessible to anyone with an internet connection.
The flood factor score takes into account cumulative flood risk and projected environmental changes—including from rain, storms, rivers, and tides—over a mortgage of 30 years. Additionally, First Street took into consideration areas that FEMA hasn’t yet mapped. The future risk scale was created by more than 80 leading researchers, data scientists, and hydrologists by analyzing dozens of past tropical storms, hurricanes, and other flooding phenomena that will only worsen with climate change. Category 4 Hurricane Laura bearing down on the Gulf Coast right now shows how valuable data like this is to homeowners or potential buyers—and how it’ll be even more valuable in the future.
The tool won’t make our climate crisis any less urgent and terrifying. But it does fill a very large hole in federally available data. And as First Street Foundation’s executive director Matthew Eby said in a statement this week, it will help property-hunters “protect what is likely their largest, most valuable asset: their home.”