DC Water broke ground on the Piney Branch Tunnel yesterday, starting the final major tunnel in its Clean Rivers Project.
The Piney Branch Tunnel project includes the construction of a tunnel approximately 800m long and 6.7m wide.
Crew will prepare the site this summer and tunnelling, which will include blasting through rock, is expected to commence in autumn.
Once completed, the Piney Branch Tunnel will capture and store at least 4.2 million gallons of rainwater and wastewater during heavy storms. The water will be transferred to the Blue Plains Water Resource Recovery Facility for treatment.
The US Environmental Protection Agency currently lists Piney Branch as an impaired waterbody under the Clean Water Act.
“We have already seen how the Clean Rivers Project can make a real difference for the Anacostia River, and this project will bring those same benefits to Rock Creek and the Potomac River,” said DC Water interim CEO and general manager Matt Brown. “The Piney Branch Tunnel is one more way we are protecting our waterways and building a cleaner, healthier future for everyone who lives, works and enjoys the outdoors in DC.”
Much of DC’s sewer system is more than 100 years old and at present around 25 combined sewer overflows occur in Pine Branch each year. The new tunnel is expected to reduce this to once a year cut the amount of overflow by 96%.
The Piney Branch Tunnel is scheduled to be finished by the end of 2029. Along with the Potomac River Tunnel, which is under construction, the project will complete the Clean Rivers Project.
