FloodZoneMap.org

Dorchester County, South Carolina Flood Zones

Check an Address in Dorchester County

Enter any address in Dorchester County, South Carolina to see its FEMA flood zone

The Flooding Character of Dorchester County

Flash flooding from thunderstorms is the most frequent flood event in Dorchester County, SC, with 62 recorded instances in the last 30 years. Tropical storms and general flooding also contribute to the risk. For example, multiple flash flood events occurred in August 2025 due to slow-moving cold fronts interacting with a moist atmosphere, leading to heavy rainfall.

National Flood Insurance Program (NFIP) data shows a significant number of claims in Zone A, averaging over $23,000 in payouts and a water depth of nearly 5 feet. Claims were also filed in Zone X, with average payouts around $22,000 and water depths approaching 6 feet. Properties located in Zone A and Zone X may face a higher risk of experiencing significant flood damage. Residents in these areas, as well as those in lower-risk zones like X_UNSHADED, X_SHADED, and UNKNOWN, should be aware of their flood risk and consider appropriate mitigation measures.

Summary generated from NOAA storm narratives and NFIP claim data for this county. Not predictive.

Read First-Hand Flood Stories from Dorchester County

39 NOAA storm reports from this county describe what happened, in the words of the meteorologists who were there.

Read South Carolina flood stories →

Flood Risk Data for Dorchester County

Dorchester County, South Carolina has recorded 99 flood-related events since 1996 according to NOAA's Storm Events Database, including 62 flash floods and 12 river or area floods. The county has received 26 federal disaster declarations, 1 of which involved flooding or coastal storms. Enter any address above to check its FEMA flood zone designation.

Dorchester County Disaster History

FEMA Disaster Declarations (1989–2026)

Disaster Declarations
26
Flood/Coastal Disasters
1
Hurricane Disasters
7
Latest Disaster
Severe Winter Storm (2026-01-21)

Source: OpenFEMA Disaster Declarations Summaries.

Recent Disaster Declarations in Dorchester County

DeclarationTypeDate
Severe Winter StormWinter StormJan 21, 2026
Hurricane HeleneTropical StormSep 25, 2024
Hurricane DebbyTropical StormAug 4, 2024
Tropical Storm DebbyTropical StormAug 4, 2024
Hurricane IdaliaHurricaneAug 29, 2023
Hurricane IanHurricaneSep 25, 2022
Covid-19BiologicalJan 20, 2020
Covid-19 PandemicBiologicalJan 20, 2020
Hurricane DorianHurricaneAug 31, 2019
Hurricane FlorenceHurricaneSep 8, 2018

Recorded Flood Events in Dorchester County

NOAA Storm Events Database (1996–2025)

Total Flood Events
99
River/Area Floods
12
Flash Floods
62
Hurricanes/Tropical Storms
25
Total Property Damage
$7.4M
Flood Injuries
1

Source: NOAA National Weather Service Storm Events Database.

Recent Flood Events in Dorchester County

TypeDateDamage
Flash FloodAug 22, 20250.00K
Flash FloodAug 16, 20250.00K
Tropical StormSep 26, 2024303.00K
Flash FloodAug 9, 202460.00K
Flash FloodAug 9, 20240.00K
Flash FloodAug 9, 202420.00K
Flash FloodAug 6, 202420.00K
Flash FloodAug 6, 202410.00K
Tropical StormAug 5, 2024
Flash FloodAug 31, 202330.00K

Dorchester County Flood History

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.

Tropical Storm — Sep 26, 2024

Helene first developed into a tropical storm in the northwest Caribbean Sea in the late morning of September 24, and strengthened into a hurricane near the Yucatan peninsula about 24 hours later. Helene continued to strengthen and became a major hurricane as it moved to the north-northeast across the eastern Gulf of Mexico. Helene made landfall in the Big Bend region of Florida in the late even...

Flash Flood — Aug 9, 2024

Debby first developed into a tropical storm about 100 miles west-southwest of Key West, Florida late afternoon on August 3rd, then gradually strengthened to a strong tropical storm while tracking north across the eastern Gulf of Mexico on August 4th. Debby then reached hurricane force strength late on August 4th about 100 miles west-northwest of Tampa, before continuing a north-northeast track ...

Flash Flood — Aug 6, 2024

Debby first developed into a tropical storm about 100 miles west-southwest of Key West, Florida late afternoon on August 3rd, then gradually strengthened to a strong tropical storm while tracking north across the eastern Gulf of Mexico on August 4th. Debby then reached hurricane force strength late on August 4th about 100 miles west-northwest of Tampa, before continuing a north-northeast track ...

Source: NOAA National Weather Service Storm Events Database.

Dorchester County NFIP Flood Insurance Claims

Total Claims Filed
646
Total Paid Out
$13.9M
Avg Claim
$29,144
Avg Water Depth
8.2 ft

Claims by Flood Zone

A Zones (High Risk)
462
V Zones (Coastal)
2
X Shaded (500-yr)
4
X Unshaded (Low)
22

Source: OpenFEMA NFIP Individual Claims (2.25M records analyzed).

Flood Zone Types in Dorchester County

FEMA assigns flood zone designations to areas in Dorchester County, South Carolina:

AE High Risk — 1% annual chance of flooding. Insurance required.

VE Very High Risk — Coastal flooding with wave action.

X (Shaded) Moderate Risk — 500-year floodplain.

X Low Risk — Outside major floodplains.

View all flood zone types →

Flood Insurance in Dorchester County

Properties in Dorchester County, South Carolina that are in FEMA-designated Special Flood Hazard Areas (zones A and V) with federally backed mortgages are required to carry flood insurance.

Even outside high-risk zones, flood insurance is recommended. From 2014 to 2024, nearly one-third of NFIP claims came from outside the high-risk Special Flood Hazard Area.

Visit FloodSmart.gov to find an agent and get a quote.