Charleston flood history
669 days with roads at risk since 2012
Record high water
9.85 ft
Sep 11, 2017 · 326 roads at risk
Days a year
~46
average since 2012
Most recent
Sep 30, 2026
7.03 ft · 14 roads at risk
On the map
The biggest days
Sep 11, 2017: 326 roads at risk9.85 ft at the Charleston gauge · 3.6 ft above the tide tables · deepest: Severe · model estimate
Estimates, not records of actual flooding. Each day is NOAA's verified high water at the tide gauge, run through FloodRoute's flood model on today's roads and elevations, in dry weather. Drains, levees, tide gates, rain, road changes and elevation error all mean real conditions differed. Not for property, real-estate, insurance, lending, engineering or legal decisions.
2012–2026
Days with roads at risk, by year
Since 2012
Highest water
| Date | High water · Charleston | vs tide tables | Roads at risk | Deepest streets (model) |
|---|---|---|---|---|
| 9.85 ft | +3.63 ft | 326Severe | Cherry Street, Courtenay Drive, Colonial Street | |
| 9.64 ft | +3.86 ft | 311Severe | Cherry Street, Courtenay Drive, Colonial Street | |
| 9.28 ft | +4.27 ft | 283Severe | Cherry Street, Courtenay Drive, Colonial Street | |
| 9.19 ft | +2.33 ft | 269Severe | Cherry Street, Courtenay Drive, Colonial Street | |
| 8.74 ft | +2.19 ft | 210Severe | Cherry Street, Courtenay Drive, Colonial Street | |
| 8.65 ft | +1.50 ft | 191Severe | Cherry Street, Courtenay Drive, Colonial Street | |
| 8.52 ft | +1.56 ft | 160Severe | Cherry Street, Courtenay Drive, Colonial Street | |
| 8.43 ft | +1.49 ft | 160Severe | Cherry Street, Courtenay Drive, Colonial Street | |
| 8.42 ft | +1.37 ft | 145Severe | Cherry Street, Courtenay Drive, Colonial Street | |
| 8.37 ft | +2.04 ft | 145Severe | Cherry Street, Courtenay Drive, Colonial Street |
Latest verified
Most recent days
| Date | High water · Charleston | vs tide tables | Roads at risk | Deepest streets (model) |
|---|---|---|---|---|
| 7.03 ft | +0.48 ft | 14Likely | Cherry Street, Courtenay Drive, Colonial Street | |
| 7.41 ft | +0.82 ft | 32Likely | Cherry Street, Courtenay Drive, Colonial Street | |
| 7.77 ft | +1.26 ft | 70Severe | Cherry Street, Courtenay Drive, Colonial Street | |
| 7.76 ft | +1.41 ft | 70Severe | Cherry Street, Courtenay Drive, Colonial Street | |
| 7.50 ft | +1.37 ft | 36Likely | Cherry Street, Courtenay Drive, Colonial Street |
Every day, every year
Browse by year
About this data: method, sources and free downloads
Since 2012, NOAA's Charleston tide gauge has recorded water high enough for FloodRoute's model to put at least one Charleston road at risk on 669 days, about 46 a year. The highest water was 9.85 ft on Monday, September 11, 2017, 3.63 ft above the tide tables; at that level the model estimates 326 Charleston roads were at risk, including Cherry Street, Courtenay Drive and Colonial Street.
For every day since 1996 we take NOAA's verified highest observed water at the tide gauge, adjust it to the town's prediction station exactly as the live forecast does (the gauge's departure from the tide tables, minus the departure already built into our calibration), and run FloodRoute's flood model on today's road network and street elevations. A day counts when at least one road in the town is at or below that water level by the model's rules. Rain is not included, so wet days were likely worse.
Gauge: NOAA 8665530 (Charleston). Heights are feet above MLLW.
Free to use under the Open Database License (ODbL) 1.0. Credit: FloodRoute (floodroute.com), © OpenStreetMap contributors, NOAA CO-OPS. Please describe it as estimates, never as observed flooding.
Cite as: FloodRoute (2026). Charleston, SC king tide flood history (model estimates). https://floodroute.com/sc/charleston/history. Open Database License (ODbL) 1.0.
FAQ
Charleston flood history: questions, answered
How often do roads flood at high tide in Charleston?
By FloodRoute's estimate, at least one Charleston road was at risk on 669 days between 2012 and Sep 30, 2026, about 46 a year. Most of those days are shallow water on a few low streets; the biggest days put dozens of roads at risk.
What was the highest tide in Charleston since 2012?
Monday, September 11, 2017: NOAA's Charleston tide gauge recorded 9.85 ft (MLLW), 3.63 ft above the tide tables. At that level FloodRoute's model estimates 326 Charleston roads were at risk, including Cherry Street, Courtenay Drive and Colonial Street.
When did a high tide last put Charleston roads at risk?
The most recent day in the verified record is Wednesday, September 30, 2026: 7.03 ft at the Charleston gauge, 14 roads at risk. NOAA verifies data with a lag of a month or two; the live forecast covers today and the weeks ahead.
Is this a record of actual flooding in Charleston?
No. Estimates, not records of actual flooding. Each day is NOAA's verified high water at the tide gauge, run through FloodRoute's flood model on today's roads and elevations, in dry weather. Drains, levees, tide gates, rain, road changes and elevation error all mean real conditions differed. Not for property, real-estate, insurance, lending, engineering or legal decisions. Neighbor flood reports in the FloodRoute app are the ground truth we use to check and improve the model.
Can I use this data?
Yes. Download it as CSV or JSON under the Open Database License (ODbL) 1.0, with attribution to FloodRoute (floodroute.com), © OpenStreetMap contributors, NOAA CO-OPS. Please describe it as estimates, never as observed flooding. More on the open data page.