Charleston Mayor William Cogswell and project partners plan to cut the ribbon Monday, Nov. 9, on the U.S. 17 Spring/Fishburne Drainage Improvement Project, the city said in an announcement published by Holy City Sinner. The ceremony is set for 9:30 a.m. at the William Dudley Gregorie Pump Station, 135 Lockwood Drive.

The city calls the five-phase project “almost 40 years in the making.” It is meant to reduce how often, how long and how badly storms flood Septima P. Clark Parkway, known as the Crosstown, and the surrounding Spring and Fishburne basins.

The work includes more than 9,000 feet of deep tunnels and more than 18,000 feet of new stormwater pipes, according to the announcement. The pump station can push 360,000 gallons a minute into the Ashley River, including during king tides, the city said.

The project covers about 20% of the peninsula, according to the city. When the Crosstown floods, the city says, it can cut off access to three major hospitals, two fire stations, four schools and police headquarters.

Its cost has climbed over the years. The city valued the project at $198 million in 2022, which was reportedly $44 million over budget, the Charleston City Paper reported. Live 5 put the total at nearly $200 million in June. The city’s announcement did not give a final figure.

The city secured preliminary funding in 1999, and construction began in 2011, Live 5 reported. The tunnels have reduced flooding by gravity alone since 2022, according to city officials. The pumps are meant to keep water moving at high tide, when gravity drainage slows.

“It’s not just people on the peninsula that are going to benefit from this project,” Steve Kirk, the city’s project management practice lead, told the station in June. “It’s people in the entire region.”