Rock Creek and Piney Branch Trunk Sewers – Washington DC

Description

To help alleviate pollution in Rock Creek, the Public Works Administration (PWA) granted approximately $3,500,000 for the creation of a massive new sewer system serving Crestwood, Petworth and surrounding areas in 1939-1941. The trunk sewer lines were constructed by private contractors, one of which was the Philadelphia construction company of Joseph Lombardi.

Beginning near the intersection of 16^th Street and Arkansas Avenue (northwest), the system runs southwest down Piney Branch Parkway, under the National Zoo, and then south.  It splits into two lines, one along each side of Rock Creek: the western line to carry storm water runoff and the eastern to carry domestic sewage). These two lines would then extend to the Potomac River, generally following the course of the creek.

The Sunday Star reported on a section of the project in August 1939: “Two deep tunnels, each large enough to admit a locomotive, are being bored and blasted through earth and solid rock at the P Street and Calvert Street Bridges to form additional links in the labyrinth of new sewers designed to abate pollution in Rock Creek… They will be the longest units in the 7½ miles of underground lines… in one of the largest sewer projects ever undertaken in the District… the huge combined sewers in the Rock Creek and Piney Branch areas will carry off house sewage and storm water run-off… Rock Creek never will be entirely freed of pollution but the condition of the creek after the sewerage job is done will be good enough to support fish life. The foul odors which now are a common cause of complaints will be removed.”  

When the Rock Creek and Piney Branch sewer system was completed in 1941, the sewage line had been linked with an interceptor that carried the waste southeast to the new PWA-funded disposal plant at Blue Plains (today called the Blue Plains Advanced Waste Water Treatment Plant). During heavy rain days, however, some overflow discharged into the Potomac River near the south end of 30^th Street; but with “dilution… expected to be so high that pollution will be negligible” (Evening Star, 1941).

The Rock Creek and Piney Branch sewer system was part of a massive New Deal investment in sanitation that cleaned up our nation’s capital.  As the Blue Plains website notes: “Before 1937, wastewater flowed through the District in open sewers and discharged untreated to the nearest waterway.”

The survival of this sewer is uncertain, though likely, and is known only to the staff of the DC Water and Sewer Authority.