The Metropolitan Sewer District has canceled plans to build a sewage storage basin in the Highlands and will instead extend the enormous underground storage tunnel it’s building underneath downtown Louisville.
When complete, the Waterway Protection Tunnel will hold up to 55 million gallons of sewage and stormwater and extend four miles underneath the city to help prevent overflows into the Ohio River and Beargrass Creek, the agency announced Monday.
The $200 million project is part of Louisville’s deal with the federal government to stop pouring raw sewage and stormwater into Kentucky waterways by 2020.
“Extending this tunnel project creates the opportunity for us to meet that goal and also to create safer, cleaner waterways in our community with less above ground impacts during construction,” said Tony Parrott, MSD executive director.
MSD’s original plans called for the underground storage tunnel to stretch 2.5 miles from 12th and Rowan streets down through Butchertown.
Construction crews will extend the tunnel an additional 1.5 miles to Lexington Road and Grinstead Drive, near the former site of Jim Porter’s Good Time Emporium.
MSD purchased that property for $5 million in 2015 to build a sewage storage basin.
Parrott said MSD spent about $4 million on construction of the basin before deciding to abandon the project in favor of extending the underground storage tunnel.
When complete, the above-ground site will serve as the trailhead for Beargrass Creek Trail and will include parking, a rain garden and a wetland preservation area, according to a news release.
Councilman Bill Hollander said that while he wishes MSD had made the decision before beginning work on the storage basin, the tunnel will be the best long-term solution.
“So I think at the end of the day we are going to have a cleaner Beargrass Creek and Ohio River, an improved Beagrass Creek greenway and a very much nicer trailhead,” he said.
Despite the money already spent on the basin, Parrott said extending the tunnel will lower operational costs and save money over the life of the project.
“We’re going to be able to increase storage capacity over the original planned project,” he said. “It’s going to be less intrusive in the community. It’s going to allow for us to minimize the above ground work that’s going to be necessary at I-64 and Grinstead.”
Construction on the Waterway Protection Tunnel began in January. Crews have already built a drop shaft more than 200-feet deep where the boring machine will enter and begin drilling later this fall, said Jacob Mathis, project manager.
The tunnel will capture 98 percent of sewage and stormwater overflows until it can be treated at the Morris Forman Water Quality Treatment Center and released into the Ohio River, Parrott said.
MSD anticipates it will still be able to meet the 2020 deadline required under the federal consent decree, even with the additional construction.
Parrot said MSD will begin bidding on some of the site work at Lexington Road and Grinstead Drive next week.
This post has been updated.