20 States With the Biggest Risk of Flooding

Methodology 

To find the states Americans should leave because of high flood risks, 24/7 Wall St. calculated the area of each state designated EPA Flood Hazard Area – areas that have a 1% annual chance of coastal or riverine flooding – as of 2020. The area and percent of each county designated Flood Hazard Area came from the Centers for Disease Control and Prevention National Environmental Public Health Tracking Network. Total state area data came from the Census Bureau and is as of 2010. We divided each state’s total flood zone area in square miles by total state area to find the overall percentage of a state area designated flood hazard area.

From FEMA’s National Risk Index, we found each county’s coastline and riverine flood risk index score and rating to list the county with the highest risk in each state.