Sewage Line Collapsed in January 2026 and Released Over 200 Million Gallons of Untreated Sewage into Potomac River
The Department of Justice, on behalf of the Environmental Protection Agency (EPA), filed a civil complaint in federal court today against the District of Columbia Water and Sewer Authority (DC Water) and the District of Columbia for claims of Clean Water Act violations from the collapse of the Potomac Interceptor resulting in the discharge of more than 200 million gallons of raw, untreated sewage into the Potomac River.
The complaint seeks financial penalties, sewer assessment and rehabilitation projects, and pollutant mitigation work to remedy DC Water’s failure to operate its sewer system in compliance with the Clean Water Act and its permits. The complaint alleges that DC Water failed to properly operate and maintain its sewer system in a manner that keeps untreated sewage out of the Potomac River and its tributaries, and other areas with risk of human contact. The complaint also seeks an order for DC Water to, at a minimum, develop an Enhanced Operations and Maintenance Plan for all its sewer lines.
“DC Water’s failure to maintain the Potomac Interceptor resulted in raw sewage flowing into the Potomac River and the surrounding environment, posing a direct risk to public health,” said Principal Deputy Assistant Attorney General Adam Gustafson of the Justice Department’s Environment and Natural Resources Division (ENRD). “As cities grow and infrastructure ages, cities must invest in their wastewater system to prevent such catastrophes. This complaint seeks to secure DC Water’s commitment to properly maintain its foundational sewage infrastructure.”
According to the complaint, DC Water operates the Potomac Interceptor, which conveys an average of up to 60 million gallons a day of sewage from parts of Northern Virginia, the District of Columbia, and Maryland to the Potomac Pump Station in Washington, D.C.
On Jan. 19, a portion of the Potomac Interceptor collapsed where it passes through the C&O Canal National Historic Park, near Lock 12, in Montgomery County, Maryland. Between Jan. 21 and 24 DC Water crews worked to install diversion pumps to route wastewater around the failed section of the Potomac Interceptor. Beginning on Jan. 24, DC Water used a portion of the C&O Canal to contain the bypassed flow until it could re-enter the Potomac Interceptor downstream of the collapse.
DC Water’s use of the C&O Canal to route sewage around the failed section of the Potomac Interceptor required multiple high-powered pumps. These pumps periodically clogged, requiring them to be taken out of service and cleaned. On Feb. 8, DC Water reported that an estimated 500,000 gallons of sewage was discharged to the Potomac River when multiple pumps had to be shut down due to clogging with rags and wipes.
When President Trump declared a FEMA emergency, the Army Corp of Engineers deployed to assist with mitigation efforts, including building stormwater diversions around locations that were still covered with sewage debris to prevent stormwater from coming into contact with harmful pollutants left behind by the deposition of untreated sewage.
In total, the Potomac Interceptor collapse resulted in unauthorized discharge of more than 200 million gallons of raw, untreated sewage to the Potomac River.
EPA investigated the case.
ENRD’s Environmental Enforcement Section filed the complaint.