Fort Moultrie Quartermaster and Support Facilities Historic District · Photo: Brian Stansberry · CC BY 3.0More hazard damage per building is expected in Sullivan's Island than in 97% of U.S. towns, mostly from hurricanes
On FEMA’s National Risk Index, Sullivan's Island gets a D− for hazard risk: higher expected damage per building than 97% of U.S. towns. Most of that expected damage is hurricanes (68%), then coastal flooding (12%). Flood insurance has paid 670 claims here since 1979.
Graded on FEMA’s expected yearly building damage per dollar of building value (NRI v1.20, December 2025), weighted by where residents live; flood claims are shown, not graded. How hazard risk is graded
What stands out about Sullivan's Island’s natural hazards
From FEMA’s model and FEMA’s records, below.
What Sullivan's Island faces
Each hazard’s share of the building damage FEMA expects here, and how its rate compares with the rest of the country.
Hurricanes
Coastal flooding
River and rain flooding
Earthquakes
Shares are of FEMA’s expected building damage, the measure the grade uses; ranks compare each hazard’s building-damage rate with all 85,154 U.S. census tracts. In FEMA’s terms, river and rain flooding is FEMA’s “Inland Flooding” (rivers and streams overflowing their banks, or rain overwhelming drainage). FEMA defines coastal flooding as high or rising tides and storm surge, so surge damage is counted there. Drought isn’t listed: FEMA counts its losses in crops only.
What’s behind Sullivan's Island’s grade
Hurricanes are 68% of the building damage FEMA expects in Sullivan's Island, and Sullivan's Island’s rate of hurricanes damage is in the top 2% of U.S. census tracts. Coastal flooding adds 12%, at a rate in the top 1% of U.S. census tracts.
D− higher expected damage per building than 97% of U.S. towns (21,298).
All of Sullivan's Island’s residents live in one census tract; the figures are that tract’s.
In dollars, FEMA expects about $3.9M a year in losses across Sullivan's Island: $3.6M to buildings, the rest to people and crops.
Does Sullivan's Island flood? Yes: 670 flood claims since 1979
Every paid claim on a federal flood insurance policy in Sullivan's Island, from FEMA’s records: 615.8 per 1,000 homes, more than 100% of the 13,809 U.S. towns with a flood insurance record.
- Hurricane Hugo546 claims · $19.9M
- The October severe storms20 claims · $244K
- Hurricane Irma14 claims · $561K
Sullivan's Island is in FEMA’s Community Rating System (class 5) for its flood-proofing work.
Insurance rates: Charleston County.7 federal disasters brought FEMA money to Sullivan's Island
Disasters that paid out in Sullivan's Island itself (aid to households or repair grants to the Town of Sullivan's Island), newest first, with that year’s flood claims.
- 2022Hurricane Ian25 households applied for aid$72K to the Town of Sullivan's Island for repairs
- 2019Hurricane Dorian$52K to the Town of Sullivan's Island for repairs
- 2018Hurricane Florence$40K to the Town of Sullivan's Island for repairs
- 2017Hurricane Irma$40K to the Town of Sullivan's Island for repairs14 flood claims paid for it, $561K
- 2016Hurricane Matthew4 households applied for aid$45K to the Town of Sullivan's Island for repairs5 flood claims paid for it, $164K
- 2015Severe Storms and Flooding16 households applied for aid$18K aid approved20 flood claims paid that year
Show all 7
- 2004Tropical Storm Gaston$6K to the Town of Sullivan's Island for repairs8 flood claims paid that year
Charleston County has had 18 natural disasters declared by the President since 1953, most often hurricanes and tropical storms, then severe storms. Not counted: the 2005 Hurricane Katrina evacuee emergency, which covered counties that took in evacuees.
Old photos of Sullivan's Island after a storm or flood belong in the town’s history. Add one, or share what you remember below.
Add to the Sullivan's Island archive →Sullivan's Island and its neighbors
Sullivan's Island is 2nd of the 3 graded towns here, from least expected damage per building to most. Tap a town to see its hazards.
| Town | Hazard risk | Mostly (buildings) | Flood claims |
|---|---|---|---|
| Isle of Palms | D−more damage than 96% | hurricanes | 2,046 |
| Sullivan's Island | D−more damage than 97% | hurricanes | 670 |
| Mount Pleasant | D−more damage than 97% | hurricanes | 1,061 |
Hazard risk = FEMA’s expected yearly building damage per dollar of building value, vs. the 21,298 U.S. towns we grade; the map is shaded by fifths of the same scale. Flood claims = paid federal flood insurance claims on record.
Get ready for what Sullivan's Island faces
A short kit for the hazards that drive the building damage here, what to check before you buy, and where neighbors get alerts.
- The season runs June through November and peaks from mid-August to mid-October.
- Bring in porch furniture and anything the wind can throw.
- Fill the gas tank and charge phones before the storm arrives.
- Know your evacuation zone and the way off the coast.
- Storm surge comes fast: leave when you’re told, not when the water arrives.
- Move cars to high ground before king tides and nor’easters.
- Turn around at flooded roads: a foot of moving water can carry off a car.
- Flood insurance usually takes 30 days to start, so buy it before the forecast.
- Keep papers and medicines up high, in a grab-and-go bag.
- Drop, cover and hold on.
- Strap tall furniture and the water heater to the wall.
- Know how to shut off the gas.
- Look up the address on FEMA’s flood map.
- Ask the seller or landlord whether it has ever flooded, and what flood insurance costs there.
- Get a flood insurance quote early: policies usually start 30 days after you buy.
- Sullivan's Island residents get 25% off flood insurance.
Know where neighbors sign up for alerts? Add it to the Handbook so everyone has it.
Questions about natural hazards in Sullivan's Island
Is Sullivan's Island at risk for natural disasters?
On FEMA’s National Risk Index, Sullivan's Island has higher expected damage per building than 97% of U.S. towns: D− for hazard risk. Most of the expected damage is hurricanes (68%) and coastal flooding (12%). The figures are for the one census tract the town shares with its neighbors. This is FEMA’s model of an average year for today’s buildings, not a forecast.
Does Sullivan's Island flood?
Flood insurance has paid 670 claims in Sullivan's Island since 1979, $21.5M in all, or 615.8 per 1,000 homes, more than 100% of U.S. towns with a flood insurance record. 27 properties have flooded more than once. The most claims came from Hurricane Hugo (546).
Is Sullivan's Island in a flood zone?
Flood zones are drawn street by street, so the answer depends on the address: look it up on FEMA’s flood map. In Charleston County, 78% of homes in mapped flood zones carry federal flood insurance, and 31.7% of all homes do.
How much is flood insurance in Sullivan's Island?
Sullivan's Island is in FEMA’s Community Rating System (class 5), which takes 25% off federal flood insurance policies for its flood-proofing work. Premiums depend on the building; policies usually start 30 days after you buy, so get a quote early.
What was the biggest storm in Sullivan's Island?
By FEMA money that reached Sullivan's Island, Hurricane Ian (2022): 25 households applied for aid, $0 approved, and $72K to the Town of Sullivan's Island for repairs. By flood claims, Hurricane Hugo: 546 paid, $19.9M.
Is Sullivan's Island at risk from hurricanes?
It is the largest share of the building damage FEMA expects here (68%), and Sullivan's Island’s rate for it is in the top 2% of U.S. census tracts.
Storm stories
Memories, warnings and help from neighbors in Sullivan's Island.
Sources: FEMA National Risk Index v1.20 (December 2025), census-tract table, combined by where Sullivan's Island’s residents lived in the 2020 census; OpenFEMA: NFIP redacted claims, multiple-loss properties, community status book and residential penetration rates, housing assistance (owners and renters), public assistance funded projects, hazard mitigation properties and disaster declarations. Homes: Census ACS 2020–24. Preparedness tips: Ready.gov. FEMA’s model is an average of expected damage, not a forecast. How hazard risk is graded.