D.C. Water held a groundbreaking ceremony for the start of construction on the Piney Branch Tunnel, a project in Rock Creek Park designed to drastically reduce the amount of runoff and wastewater that ends up in area waterways after heavy rains.
Matt Brown, D.C. Water’s interim CEO and general manager, said at Thursday’s groundbreaking along Piney Branch Parkway, “right now, in an average year we have about 25 overflows,” instances where runoff and wastewater flow into local waterways.
“Because of this tunnel, we will reduce that number in an average year down to one,” he added.
The Piney Branch Tunnel is the final installation in the Clean Rivers Project.
“The tunnel will capture 4.2 million gallons of combined sewage. The tunnel will be about a half a mile long, 22 feet in diameter,” and the project is expected to be completed by late 2029, Brown said.
“Piney Branch, which has long borne the brunt of the heavy stormwater and sewage flows, will finally recover and become the healthy, functioning system that it was intended to be,” said Brian Joyner, National Park Service superintendent for Rock Creek Park.
Joyner said construction along Piney Branch Parkway will affect area neighborhoods and drivers who travel the parks’ roadways.
“We want to acknowledge the disruption that this project will bring, and thank park visitors and residents for their patience for the next four years of construction,” Joyner said.
Joyner said when complete, the tunnel will result in “one of the most important environmental improvements in park history.”
Julianna Gonen, Advisory Neighborhood Commissioner for neighborhoods including Crestwood and 16th Street Heights, told WTOP, “Crestwood is surrounded on three of four sides by Rock Creek Park. It’s what defines the neighborhood and makes it so special. This project is going to help keep the creek healthy for years to come.”
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