Flooding is the most common and costly natural disaster in the United States. Every county faces some flood risk, but a small number of counties face extreme exposure due to geography, elevation, and proximity to rivers or coastlines.
Using FEMA National Risk Index flood risk scores, we identified the 25 counties with the worst flood risk in America. These scores reflect both the probability of flooding and the potential damage to buildings and infrastructure.
The 25 Counties with the Worst Flood Risk
Los Angeles County, California has the highest flood risk score at 100. These counties face the greatest flood exposure nationally:
Important
Standard homeowner insurance policies do not cover flood damage. If you live in a high flood-risk county, consider purchasing flood insurance through the National Flood Insurance Program (NFIP) or a private insurer.
Methodology
Flood risk scores come from the FEMA National Risk Index (2020), measuring expected annual loss from riverine and coastal flooding at the county level. Scores are percentile ranks on a 0-100 scale. Counties are ranked by flood risk score in descending order.
Data source: FEMA National Risk Index (NRI). Risk scores use percentile-rank methodology on a 0-100 scale. All figures are relative rankings and do not represent absolute predictions of natural disaster occurrence.