Aiken County, South Carolina Natural Disaster Risk
FEMA National Risk Index assessment · SC
MediumComposite Risk Score
National percentile: 84th
Aiken County faces medium composite natural disaster risk (NRI Risk Index score 84.2, 84th national percentile), driven primarily by ice storm and lightning exposure. Expected annual loss across all 18 hazard types is $48M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
Aiken County carries a medium composite natural disaster risk, with a National Risk Index score of 84.2 out of 100 — placing it in the 84th national percentile and near the national midpoint for natural-disaster risk. The score blends Expected Annual Loss, Social Vulnerability, and Community Resilience across all 18 FEMA hazard types.
Most of Aiken County's expected losses come from ice storm (freezing rain that coats surfaces in heavy, damaging ice) at High risk — $1M in expected annual loss and about 1.16 events per year; lightning (electrical discharges from storms that ignite fires and cause casualties) at High risk — $1M in expected annual loss and about 61.37 events per year; and hurricane (tropical cyclones bringing extreme wind, rain, and storm surge) at Medium risk — $7M in expected annual loss and about 0.14 events per year. Across all hazards, FEMA estimates $48M in expected annual loss for a population of 169K.
Beyond physical exposure, Aiken County has a medium social vulnerability rating (how susceptible the population is to harm) and a low community resilience rating (its capacity to prepare for and recover from disasters). Both measures sit toward the lower end, indicating relatively modest population sensitivity.
The county's disaster history tells the same story: Aiken County has received 24 federal disaster declarations since 1977, including 10 for hurricane events and 3 for severe storm events. The most recent was Severe Winter Storm (winter storm), declared in January 2026.
Among 46 South Carolina counties, Aiken County ranks #18 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Ice Storm | High | 1.16 / yr | $1M |
| Lightning | High | 61.37 / yr | $1M |
| Hurricane | Medium | 0.14 / yr | $7M |
| Earthquake | Low | 0.00 / yr | $4M |
| Tornado | Medium | 0.71 / yr | $5M |
| Heat Wave | Medium | 4.63 / yr | $2M |
| Riverine Flood | Medium | 0.43 / yr | $23M |
| Wildfire | Low | 0.00 / yr | $466K |
| Landslide | Low | 0.45 / yr | $16K |
| Hail | Medium | 3.19 / yr | $591K |
| Strong Wind | Medium | 4.94 / yr | $943K |
| Cold Wave | Medium | 0.21 / yr | $2M |
| Drought | Low | 30.88 / yr | $236K |
| Winter Weather | Low | 1.58 / yr | $64K |
| 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 |
Disaster History
Aiken County has received 24 federal disaster declarations since 1977, most recently Severe Winter Storm in January 2026. Most frequent causes: Hurricane (10), Severe Storm (3), Severe Ice Storm (3).
| Declared | Type | Disaster |
|---|---|---|
| January 2026 | Winter Storm | Severe Winter Storm |
| September 2024 | Hurricane | Hurricane Helene |
| September 2024 | Tropical Storm | Hurricane Helene |
| August 2024 | Tropical Storm | Hurricane Debby |
| August 2023 | Hurricane | Hurricane Idalia |
| November 2022 | Hurricane | Hurricane Ian |
| September 2022 | Hurricane | Hurricane Ian |
| May 2020 | Severe Storm | Severe Storms, Tornadoes, and Straight-Line Winds |
| March 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
Showing the 10 most recent of 24 declarations.
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Aiken County?
Aiken County has a composite FEMA National Risk Index score of 84.2 out of 100, placing it in the Medium category and the 84th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Aiken County?
The three highest-rated hazards are Ice Storm (High, $1M EAL), Lightning (High, $1M EAL), Hurricane (Medium, $7M EAL). These account for most of the county's expected annual losses.
How does Aiken County compare to other South Carolina counties?
Aiken County ranks #18 of 46 South Carolina counties for overall natural disaster risk, with a medium rating.
How many federally declared disasters has Aiken County had?
FEMA records 24 federal disaster declarations for Aiken County since 1977, most often 10 for hurricane events and 3 for severe storm events. The most recent was Severe Winter Storm, declared in January 2026.
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. Aiken County's $48M EAL is a statistical average, not a guarantee for any specific year or address.