19,289 flood insurance claims·$312.0M paid·9 federal flood & hurricane disasters
Share of the whole county outline, rivers and lakes included; parts FEMA hasn’t mapped count as zero.
Shaded areas are FEMA’s mapped flood hazard zones in and around Charleston County, South Carolina. Zoomed out they are simplified; at street level the map switches to FEMA’s exact layer. Tap anywhere to check that spot, or search an address above.
Charleston County, SC experiences a flood risk profile dominated by frequent flash floods and coastal flooding events. Over the last 30 years, NOAA records show 301 flash flood events (resulting in 1 death) and 284 coastal flood events, alongside 68 tropical storm events, 17 storm surge or tide events, 9 general floods, 7 tropical depressions, and 7 hurricanes. Coastal flooding is driven by factors such as strong northeast winds, offshore low pressure, and astronomical influences from full moons and perigee, as observed during the October 2025 coastal flood event where a maximum tide level of 7.91 ft MLLW was recorded at the Charleston Harbor tide gage.
National Flood Insurance Program claims data demonstrates widespread risk across multiple zones. Zone A accounts for the highest volume with 15,673 claims averaging $23,137 payouts and an average recorded water depth of 5 inches. Zone V properties recorded 1,255 claims with an average payout of $34,241 and an average water depth of 6 inches. Zone X properties logged 1,165 claims averaging a $23,262 payout with an average water depth of 8 inches, while Zone X_UNSHADED recorded 581 claims averaging $13,390 with a 4-inch average water depth, and Zone X_SHADED saw 561 claims averaging $18,642 with a 3-inch average water depth.
Property owners in Zone A and Zone V should pay the closest attention due to the high volume and severity of claims, while residents in all Zone X designations must also remain aware given the hundreds of historical claims and recorded water depths averaging up to 8 inches in those areas.
Summary written from NOAA storm reports and NFIP claims for this county. Not a prediction.
6% of Charleston County’s flood insurance claims were on properties rated outside FEMA’s high-risk zones.
18,070 NFIP claims with a recorded rated flood zone, 1978 to date. The zone is the one FEMA used to rate that policy, which may not match today’s map. Source: OpenFEMA NFIP claims.
In flood insurance claims here that reported a flood depth, the average was 5 inches.
Drawn to scale against an 80-inch door. Even a few inches soaks flooring, the bottom of the drywall and anything plugged in near the floor.
Average of the depths reported on claims (zero and implausible values left out); FEMA’s record doesn’t say exactly where each depth was measured. Source: OpenFEMA NFIP claims.
The worst year was 1989, with 9,499 claims and $181.2M paid, the year of Hurricane Hugo.
Bar height is scaled by square root so ordinary years stay visible next to the worst one. NFIP claims by year of loss. Source: OpenFEMA.
260 NOAA storm reports from Charleston County describe what happened, in the words of the forecasters who covered it. Read the South Carolina flood stories →
27 federal disaster declarations since 1977, 9 of them floods, coastal storms or hurricanes.
| Disaster | Began |
|---|---|
| Severe Winter Storm | Jan 21, 2026 |
| Hurricane Helene | Sep 25, 2024 |
| Hurricane Debby | Aug 4, 2024 |
| Hurricane Idalia | Aug 29, 2023 |
| Hurricane Ian | Sep 25, 2022 |
| Hurricane Dorian | Aug 31, 2019 |
| Hurricane Florence | Sep 8, 2018 |
| Hurricane Irma | Sep 6, 2017 |
Weather and water disasters only; most recent first. Source: OpenFEMA Disaster Declarations.
693 since 1996: 301 flash floods, 9 river or area floods and 301 coastal floods or surges.
| Event | Date | Damage |
|---|---|---|
| Flood | Aug 24, 2025 | — |
| Flash Flood | Aug 23, 2025 | — |
| Flash Flood | Aug 22, 2025 | — |
| Flash Flood | Aug 16, 2025 | — |
| Coastal Flood | Oct 11, 2025 | — |
| Flash Flood | Aug 11, 2025 | — |
| Coastal Flood | Oct 10, 2025 | — |
| Coastal Flood | Oct 10, 2025 | — |
— = no damage estimate in the record. Source: NOAA Storm Events Database.
Flood · Aug 24, 2025. Deep moisture residing across the area in advance of low pressure developing and passing off the coast led to an environment capable of flooding in poorly drained areas.
Flash Flood · Aug 23, 2025. Mid-level energy tracking across the region along with a deep moisture and modest instability residing near a stalled front led to an environment supportive of heavy rainfall across Southeast South Carolina.
Flash Flood · Aug 22, 2025. A slow moving cold front encountering an environment displaying deep moisture and moderate instability supported thunderstorms capable of heavy rainfall across Southeast South Carolina.
Flash Flood · Aug 16, 2025. A weak cold front encountering deep moisture led to slow moving thunderstorms capable of producing heavy rainfall across Southeast South Carolina.
National Weather Service narratives, lightly trimmed. Source: NOAA Storm Events Database.
Every colour on the map above is a place on this drawing: where the ground sits relative to the flood FEMA plans for.
If a building in Charleston County is in a high-risk zone (A or V) and its mortgage comes from a federally regulated or insured lender, or is federally backed, flood insurance is required.
Outside those zones it is optional, and often worth having: from 2014 to 2024 nearly one-third of NFIP claims came from outside the high-risk Special Flood Hazard Area. Since Risk Rating 2.0, NFIP premiums are set for each building, so the only reliable price is a quote: FloodSmart.gov or a local agent.