What is it?
The probability of a property in a county being damaged by flooding over the next 30 years, accounting for both FEMA flood zones and climate-adjusted projections. First Street Foundation's dataset extends FEMA's by including climate change.
Why it matters
Floods damage homes, displace residents, contaminate drinking water with sewage and chemicals, and disrupt healthcare access. Long-term flooded-area residence is associated with mental health harms (anxiety, PTSD) on top of acute injury risk.
Reference value
Counties where more than 15% of properties face substantial 30-year flood risk are in an elevated band.
Data source
FEMA NRI + First Street Foundation · View source →