Dillon County, South Carolina Natural Disaster Risk
FEMA National Risk Index assessment · SC
MediumComposite Risk Score
National percentile: 84th
Dillon County faces medium composite natural disaster risk (NRI Risk Index score 84.3, 84th national percentile), driven primarily by hurricane and strong wind exposure. Expected annual loss across all 18 hazard types is $35M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
Dillon County carries a medium composite natural disaster risk, with a National Risk Index score of 84.3 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.
The county's risk is driven primarily by hurricane (tropical cyclones bringing extreme wind, rain, and storm surge) at High risk — $20M in expected annual loss and about 0.25 events per year; strong wind (damaging straight-line winds outside of tornadoes and hurricanes) at High risk — $1M in expected annual loss and about 3.59 events per year; and earthquake (ground shaking from sudden movement along geologic faults) at Low risk — $2M in expected annual loss and about 0.00 events per year. Across all hazards, FEMA estimates $35M in expected annual loss for a population of 28K.
Beyond physical exposure, Dillon County has a very high 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). That combination — a more vulnerable population with limited resilience — can amplify the human cost of any given event.
History supports the rating: Dillon County has received 29 federal disaster declarations since 1989, including 16 for hurricane events and 3 for tropical storm events. The most recent was Severe Winter Storm (winter storm), declared in January 2026.
Among 46 South Carolina counties, Dillon County ranks #17 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Hurricane | High | 0.25 / yr | $20M |
| Strong Wind | High | 3.59 / yr | $1M |
| Earthquake | Low | 0.00 / yr | $2M |
| Wildfire | Low | 0.00 / yr | $310K |
| Tornado | Medium | 0.22 / yr | $3M |
| Ice Storm | Medium | 0.78 / yr | $239K |
| Cold Wave | Low | 0.47 / yr | $1M |
| Heat Wave | Low | 8.00 / yr | $412K |
| Riverine Flood | Low | 0.18 / yr | $6M |
| Hail | Low | 3.43 / yr | $261K |
| Lightning | Medium | 56.44 / yr | $211K |
| Winter Weather | Low | 2.47 / yr | $46K |
| Drought | Low | 14.73 / yr | $79K |
| Landslide | Very Low | 0.07 / yr | $51 |
| Avalanche | Very Low | 0.00 / yr | $0 |
| Coastal Flood | Very Low | 0.01 / yr | $0 |
| Tsunami | Very Low | 0.00 / yr | $0 |
| Volcanic Activity | Very Low | 0.00 / yr | $0 |
Disaster History
Dillon County has received 29 federal disaster declarations since 1989, most recently Severe Winter Storm in January 2026. Most frequent causes: Hurricane (16), Tropical Storm (3), Severe Ice Storm (3).
| Declared | Type | Disaster |
|---|---|---|
| January 2026 | Winter Storm | Severe Winter Storm |
| September 2024 | Tropical Storm | Tropical Storm Debby |
| 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 |
| March 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| September 2019 | Hurricane | Hurricane Dorian |
Showing the 10 most recent of 29 declarations.
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Dillon County?
Dillon County has a composite FEMA National Risk Index score of 84.3 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 Dillon County?
The three highest-rated hazards are Hurricane (High, $20M EAL), Strong Wind (High, $1M EAL), Earthquake (Low, $2M EAL). These account for most of the county's expected annual losses.
How does Dillon County compare to other South Carolina counties?
Dillon County ranks #17 of 46 South Carolina counties for overall natural disaster risk, with a medium rating.
How many federally declared disasters has Dillon County had?
FEMA records 29 federal disaster declarations for Dillon County since 1989, most often 16 for hurricane events and 3 for tropical 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. Dillon County's $35M EAL is a statistical average, not a guarantee for any specific year or address.