Federal Government Sues DC Water Over Potomac Sewage Disaster

The U.S. Department of Justice sued the District of Columbia Water and Sewer Authority on Monday over a catastrophic sewage spill that dumped hundreds of millions of gallons of raw, untreated waste into the Potomac River.

The complaint, which was filed in federal court, is the most recent and consequential legal action since the Jan. 19 collapse of the Potomac Interceptor, a 72-inch-diameter sewer line initially constructed in the 1960s that passes through the C&O Canal National Historical Park, which spans 184.5 miles, near Montgomery County, Maryland.

According to the U.S. Environmental Protection Agency, the collapse resulted in about 240 million gallons of raw wastewater flowing into the Potomac River until an emergency bypass went live on Jan. 24.

The DOJ’s lawsuit follows a federal emergency declaration, congressional criticism, and at least one major class-action lawsuit against the District of Columbia Water and Sewer Authority, known colloquially as DC Water.

“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,” Principal Deputy Assistant Attorney General Adam Gustafson of the Justice Department’s Environment and Natural Resources Division said in a statement. “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.”

The utility issued a response Monday.

“From the outset, DC Water’s highest priority was to safely and quickly contain the overflow and repair the damaged section of the Potomac Interceptor,” the utility said. “Crews implemented an emergency bypass system that successfully managed the majority of the overflow within five days and fully stopped all discharges to the Potomac River within 21 days. The repairs of the affected segment were completed in 55 days.”

DC Water said it’s also accelerating the rehabilitation of more than 2,700 linear feet of pipeline that had already been scheduled for maintenance.

The Potomac River was named the most endangered river in the United States for 2026 by the conservation group American Rivers.

The Justice Department’s lawsuit comes after weeks of mounting legal and political pressure on DC Water, a utility serving the District of Columbia as well as parts of Maryland and Virginia. Federal regulators say DC Water is responsible for the pipe, and that it had been corroding for more than a decade.

The federal government increased its response by mid-February, approving an emergency declaration on Feb. 21. President Donald Trump said on Truth Social on Feb. 16 that the event represented a “massive ecological disaster” and criticized what he called the “gross mismanagement” of local leaders.

Emergency repairs concluded March 14, and wastewater flow was restored through the Potomac Interceptor, precluding further need for the emergency bypass. The utility said approximately nine to 10 months of long-term rehabilitation work is needed.

The EPA announced March 16 it would take over water quality sampling handled previously by the DC Department of Energy and Environment (DOEE). Water quality samples are being taken regularly, processed, and posted to DOEE’s Potomac Interceptor Monitoring website.