Apr
17
2024
From The Blog
Stormy Skies and Water on Roads Last Thursday – Here’s What Happened
In case you missed it: Kiawah experienced coastal flooding on Thursday, April 11 due to the correlation of heavy rainfall and an almost seven foot king tide. Forecasters predicted up to 1.75 inches of rainfall the evening before the storm and Kiawah received 4.17 inches in some areas. Flooding on the Kiawah Island Parkway created the need for a traffic detour for around one hour, and standing water was witnessed in many areas of the island. Below is a detailed review of the storm and KICA’s actions.
On Wednesday, April 10 at 6 p.m. a notification from National Weather Service Charleston forecast 0.75 – 1.75 inches of possible rainfall. An update issued the next morning, April 11 at 6 a.m. (once the storm had already begun) included a new forecast of to 2 – 3 inches of rainfall. Rainfall varied across the greater Charleston area and on Kiawah Island. Post-storm, WCBD meteorologist Rob Fowler commented that the rain came earlier, lasted longer and was heavier than predicted.
The KICA Maintenance rain gauge recorded 4.17 inches of rainfall on April 11, which all occurred prior to 12:30 p.m. The heaviest part of the storm occurred between 8:30 – 9:25 a.m. For a short time at its peak, rain was falling at a rate of over one inch per hour. Per National Weather Service Charleston, April 11, 2024 set a record for daily rainfall in the Greater Charleston area. The previous record was 1.75 inches. To date, we are above average in rainfall for the year, due to an El Nino effect, which has created a wetter winter and spring for our area.
There were several areas where we experienced water on roads, dropping traffic to a single lane. These included:
- Governors Drive near Osprey Point Golf Course
- Kiawah Beach Drive, between Greensward Road and Fairway Oaks
- Kiawah Island Parkway. Moving west to east:
- Just past the first hill before first Sea Marsh
- Just prior to second Sea Marsh
- Between Sora Rail & fire station
An emergency contractor responded to the island in the morning to assist in areas with significant water on roads. The Kiawah Island Parkway was detoured for approximately one hour, as KICA teams and our contractor worked to safely clear two locations of water, while Security guided traffic through a third location. At all locations, plus several others around the island, our emergency contractor cleared drainage lines of debris, opening full water flow to the drainage basins. KICA’s crews used mobile pumps in various areas to remove water from the road, directing it to a drainage basin.
Prior to the storm, all drainage basins were closed to incoming high tides as we were in a king tide cycle. This also permitted capacity to handle rainfall. High tide occurred at 11 a.m. at 6.992 feet, as measured at the Kiawah River bridge, approximately 1 foot higher than forecast. Once high tide passed, our Lakes team opened gates at our drainage basins to begin releasing water from the storm. Several larger drainage basins drained through the night until normal levels were achieved.
View detailed geographic view of Charleston rainfall totals.