South Carolina coastal flooding risk
Charleston County has the highest coastal flooding risk in South Carolina, scoring 99.8 out of 100 — rated "Very High" by FEMA's National Risk Index.
| # | County | NRI score | Rating |
|---|---|---|---|
| 1 | Charleston County | 99.8 | Very High |
| 2 | Beaufort County | 94.2 | Relatively High |
| 3 | Horry County | 87.6 | Relatively High |
| 4 | Georgetown County | 86.4 | Relatively High |
| 5 | Berkeley County | 78.6 | Relatively Moderate |
| 6 | Colleton County | 78.2 | Relatively Moderate |
| 7 | Dorchester County | 59.2 | Relatively Low |
| 8 | Jasper County | 59 | Relatively Low |
| 9 | Hampton County | 24.2 | Very Low |
| 10 | Williamsburg County | 23 | Very Low |
| 11 | Marion County | 17.2 | Very Low |
| 12 | Clarendon County | 0 | No Rating |
| 13 | Dillon County | 0 | No Rating |
| 14 | Florence County | 0 | No Rating |
Source: FEMA National Risk Index v1.20.0, December 2025. Scores are 0–100 percentile rankings among all US counties. See the methodology page for definitions. Download the full CSV for all counties.
Coastal Flooding risk nationally:
Other hazard risks in South Carolina:
Frequently asked questions
What is the highest coastal flooding risk county in South Carolina?
Charleston County, SC has the highest coastal flooding risk in South Carolina, with a FEMA National Risk Index score of 99.8 out of 100 (rated "Very High").
How many counties in South Carolina are rated Very High for coastal flooding risk?
1 of 14 scored South Carolina counties are rated "Very High" for coastal flooding risk by FEMA's National Risk Index.
What causes coastal flooding risk in South Carolina?
Coastal flooding scores cover storm surge, wave action, and tidal flooding along the Gulf, Atlantic, and Pacific coasts, and Great Lakes shoreline. Inland flooding is scored separately. Counties with "Not Applicable" ratings have no significant coastal exposure. Coastal flood events are reported at zone level in NOAA Storm Events and are not included in county-level counts.