Chester County
South Carolina — Natural Disaster Risk Assessment
LowComposite Risk Score
National percentile: 43th
Chester County faces low composite natural disaster risk (NRI Risk Index score 43.2, 43th national percentile), driven primarily by ice storm and lightning exposure. Expected annual loss across all 18 hazard types is $11M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Top Hazards
All 18 Hazard Risks
| Ice Storm | High | 1.93 / yr | $394K |
| Lightning | Medium | 53.15 / yr | $498K |
| Tornado | Medium | 0.41 / yr | $2M |
| Earthquake | Low | 0.00 / yr | $690K |
| Cold Wave | Medium | 0.21 / yr | $1M |
| Strong Wind | Medium | 4.65 / yr | $653K |
| Hurricane | Low | 0.10 / yr | $249K |
| Wildfire | Very Low | 0.00 / yr | $28K |
| Riverine Flood | Low | 0.39 / yr | $4M |
| Landslide | Very Low | 0.75 / yr | $579 |
| Heat Wave | Low | 3.05 / yr | $194K |
| Drought | Low | 26.64 / yr | $57K |
| Hail | Very Low | 4.90 / yr | $94K |
| Winter Weather | Very Low | 3.68 / yr | $15K |
| Avalanche | Very Low | 0.00 / yr | $0 |
| Coastal Flood | Very Low | 0.00 / yr | $0 |
| Tsunami | Very Low | 0.00 / yr | $0 |
| Volcanic Activity | Very Low | 0.00 / yr | $0 |
Frequently Asked Questions
What is the overall natural disaster risk for Chester County?
Chester County has a composite FEMA National Risk Index score of 43.2 out of 100, placing it in the Low category and the 43th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Chester County?
The three highest-rated hazards are Ice Storm (High, $394K EAL), Lightning (Medium, $498K EAL), Tornado (Medium, $2M EAL). These account for most of the county's expected annual losses.
How does Chester County compare to other South Carolina counties?
Chester County ranks #39 of 46 South Carolina counties for overall natural disaster risk, with a low rating.
What does Expected Annual Loss (EAL) mean?
EAL is FEMA's estimate of average annual dollar losses from natural hazards, calculated from historical event data and exposure models. Chester County's $11M EAL is a statistical average, not a guarantee for any specific year or address.