POTOMAC, MARYLAND — D.C. Water will begin emergency rehabilitation work on a 1,700-foot section of the Potomac Interceptor sewer line in Potomac, Maryland. The repair site is at Muddy Branch near Pennyfield Lock, designated as Lock 22 on the Chesapeake and Ohio Canal.

Inspections of the pipe section identified structural deterioration, corrosion, and exposed rebar, which required immediate attention. Crews are constructing an above-ground temporary bypass pipeline and pumping system to divert wastewater during the rehabilitation construction, which is expected to continue through the end of September 2026.

Matt Brown, chief operating officer of D.C. Water, stated the agency's response. "As soon as we identified the severity of the deterioration in this section of the interceptor, we moved quickly to put monitoring and protective measures in place and advance an emergency repair. We understand the public concern and are monitoring conditions closely, coordinating with our partners, and taking every step we can to reduce risk and protect public water supplies, public health and the environment.", Brown said.

D.C. Water notified WSSC Water in mid-April that the pipe conditions necessitated high-priority emergency repairs. Crews are performing twice-weekly visual inspections and installing flow monitoring equipment to detect potential leaks or structural failure. The portion of the pipe that is most deteriorated is encased in concrete.

The current repair location is upstream of drinking water intakes for WSSC Water and the Washington Aqueduct. A spill at this site would impact these intakes. The Fairfax Water intake is farther upstream and would remain unaffected by a spill at this location.

On January 19, 2026, a failure of the Potomac Interceptor released approximately 240 million gallons of wastewater into the Potomac River. This failure occurred along the Clara Barton Parkway inside the Capital Beltway, downstream of drinking water intakes for WSSC Water, the Washington Aqueduct, and Fairfax Water.

Following the January spill, the federal government and Maryland filed lawsuits against D.C. Water three months later. The Maryland attorney general alleges in a lawsuit that D.C. Water was negligent and should cover cleanup and restoration costs. D.C. Water officials stated in 2018 that the Potomac Interceptor required critical repairs.

In early June 2026, the D.C. Water board of directors voted to remove CEO David Gadis. Gadis previously served as a top executive for Veolia, an engineering firm that settled civil claims related to the Flint, Michigan, water crisis.

Member of the U.S. House of Representatives Diana DeGette asked about past repair requests. "Isn't it true that in 2018, eight years ago, D.C. Water requested fast-track permits to repair widespread corrosion and detach rebar at the side of the rupture?" DeGette asked. Representative Gary Palmer commented on the situation. "I think this is the famous movie line 'a failure to communicate,' because this could have been avoided." Palmer said.