Charleston’s biggest stormwater project is finished. The question now for drivers, hospitals and businesses along the Crosstown is how much drier the next storm will be.
City leaders marked the completion of the U.S. 17 Spring/Fishburne Drainage Improvement Project with a ribbon cutting Monday, Nov. 9, at the William Dudley Gregorie Pump Station on Lockwood Drive, according to the city and WCSC Live 5. The station put the cost at about $198 million and called it the city’s largest stormwater project.
The city says the five-phase project was almost 40 years in the making. It “sharply reduces how often, how long and how badly storms flood” the Septima P. Clark Parkway, known as the Crosstown, and the surrounding Spring and Fishburne drainage basins, according to the city’s announcement of the ceremony.
What got built
“The pump station is just the tip of the iceberg. The vast majority of the project is underground,” Steve Kirk, the city’s stormwater project management practice lead, told Live 5.
Kirk said the system includes about a mile and a half of tunnel, 12 feet and 8 feet in diameter, plus 18,000 linear feet of new pipes and boxes running through the two basins. The city’s announcement put the deep tunnels at more than 9,000 feet.
The pump station can move 360,000 gallons of water a minute into the Ashley River, even during king tides, the city said. Kirk told Live 5 it could drain an Olympic-size swimming pool in less than two minutes.
How much it can handle
The area served by the pump station covers nearly 550 acres, about one-fifth of the peninsula, said Stephen O’Connell, a project director with engineering firm Black & Veatch. The station is designed to keep the U.S. 17 corridor dry during a 10-year storm and to drain water against high tides, including king tides, Live 5 reported. O’Connell said it was also designed with future sea level rise in mind.
The system has been draining the area by gravity alone since 2022, city officials told Live 5 in June. The pumps are meant to keep water moving at high tide, when gravity drainage slows.
What it won’t fix
The project will not end flooding in Charleston, O’Connell said.
“So, you will have flooding still, but hopefully that flooding time and the duration of that flooding is reduced and the depth of that flooding is reduced,” he said.
Mayor William Cogswell said the work has to fit a wider plan. “Water is not something that you can just deal with here because it’ll then go over here,” he said. “So you have to work on a system that addresses it holistically.”
The medical district and the business case
When moderate to heavy rain falls within a few hours of high tide, the Crosstown can become impassable for hours, according to the city’s project page. That cuts off access to two fire stations, three major hospitals including the VA hospital and MUSC’s Level 1 trauma center, four schools, police headquarters, the National Guard center and the Army Corps of Engineers’ headquarters, the city says. Its list of affected parties also includes businesses and residents in the area.
The three medical centers serve nearly 500,000 patients a year, Live 5 reported in June. Kirk said then that the U.S. 17 corridor is a hurricane evacuation route and that “reducing the drainage challenges that we have there significantly improves access to health care.”
The project also drains part of the medical district. “The medical district realized that they had an area that needed some additional drainage as well,” Kirk told the station. “And so we were actually able to leverage the Spring Fishburne project to be able to drain the Ehrhardt Street portion of the medical district.”
That piece, a deep tunnel extension and drop shaft at Ehrhardt Street that feeds the Spring/Fishburne tunnels and pumps, reached substantial completion in March 2024, according to the city. The city received $9,964,190 in federal Community Development Block Grant Mitigation money for it through the South Carolina Disaster Recovery Division, with a city match of $4,245,646.
O’Connell said the benefit reaches past the hospitals. “Anyone who drives in downtown, anyone who works in downtown, anyone who lives in downtown will be impacted positively by this piece of infrastructure,” he said.
Cost and partners
The city secured preliminary funding in 1999, but construction did not begin until 2011, Live 5 reported in June. The project involved more than two decades of planning, design and partnerships, including with the S.C. Department of Transportation, Live 5 reported.
The city’s ceremony lineup included S.C. Transportation Secretary Justin Powell and John White, chairman of the South Carolina Transportation Infrastructure Bank, along with engineers from Black & Veatch and Davis & Floyd. The announcement did not say what each partner paid.
What comes next
Above ground, the project adds landscaping and traffic and pedestrian safety improvements, including a pedestrian connection across the Crosstown, Live 5 reported.
“We could have just paved all this over, but we’ve done a nice landscaping. We’re connecting across the Septima Clark crosstown for pedestrian safety improvements,” Cogswell said.
City leaders described Spring/Fishburne as one part of a broader stormwater management plan. The city’s stormwater department lists other projects on its website, including a pump station at Huger and King streets, a Low Battery seawall repair and the Forest Acres and Church Creek drainage projects.
