DC Water reports that wastewater is no longer escaping from a damaged section of the Potomac Interceptor, a major sewer line that conveys wastewater from portions of Montgomery County to treatment facilities in the District.
This marks a milestone in efforts to contain the collapse of the sewer line that bled raw sewage into a section of the C&O Canal in Montgomery County earlier this month.
In a statement, DC Water confirmed that no sanitary sewer overflows were reported escaping the damaged pipe during a recent 24-hour monitoring period. It is the first time since the collapse was discovered that wastewater has been fully contained.
The agency attributed the progress to activating a temporary bypass system that uses high-capacity pumps to reroute sewage around the collapsed section of the interceptor. The bypass diverts wastewater into an isolated section of the C&O Canal before returning it to the sewer system farther downstream.
With the flow stabilized, DC Water said crews have begun excavation at the collapse site to assess damage and plan permanent repairs.
Major progress today at the Potomac Interceptor site: no sanitary sewer overflows from the damaged section in the past 24 hours.⁰⁰Crews remain on site as excavation continues. Federal, state, and local officials also visited to see the work up close. 🔗 https://t.co/n90szbmPg2 pic.twitter.com/M34mpNCiI2
— DC Water (@dcwater) January 29, 2026
Although active overflows have stopped, DC Water noted that residual wastewater remains in the creek bed near the site. Crews continue to monitor conditions and manage cleanup as work progresses.
The agency said cold weather has presented challenges, affecting ground conditions and equipment operations, but crews remain on site around the clock.
DC Water is coordinating with multiple regulatory and environmental agencies, including the Environmental Protection Agency and the Maryland Department of the Environment, as repair and monitoring efforts continue.
No timeline has been announced for the completion of permanent repairs.
