The First Street Tunnel is one of thirteen miles of tunnels supporting the District of Columbia Water and Sewer Authority (DC Water) Clean Rivers Program. DC Clean Rivers is a significant infrastructure program designed to capture and clean water during heavy rainfalls before it reaches DC’s rivers. The tunnel is also a component of the Anacostia River Projects, which are being implemented by DC Water to comply with the requirements of a Consent Decree entered into by DC Water, the District of Columbia, and the U.S. Environmental Protection Agency (EPA).
The 2,700 feet long; 20-feet in diameter tunnel was designed to control combined sewer overflows (CSOs) to the Anacostia River and mitigate flooding in the Northeast Boundary area, which includes the Bloomingdale and LeDroit Park neighborhoods. It extends under First Street NW, heading southbound to Rhode Island Ave., NW. at a depth of 80 to 160 feet below ground. An Earth Pressure Balancing Machine (EPBM), which is a type of tunnel boring machine, was used to excavate the tunnel.
Shrewsberry assisted with construction management services for the CSO tunnel. Additionally, Shrewsberry provided field engineering, tunnel inspection and document control.