DC Water and its contractors today began work to install the bypass pumps which arrived today and will help contain a sanitary sewer overflow into the Potomac River along Clara Barton Parkway in Montgomery County, MD and the C & O Canal National Historic Park. The pumps will help divert the flow around the damaged section of the Potomac Interceptor sewer line, to contain the overflow and allow excavation and repairs to begin.

To prepare for the bypass, the upper lock gates at Locks 11, 12, and 13 on the Canal were removed so the wastewater can flow downstream, where it will be pumped back into the sewer pipe.  This required careful coordination with the National Park Service to preserve the historic locks and canal while balancing the need to protect public health and safety.  

Partial bypass operations are expected to begin as early as this weekend. The pumps will be positioned at several locations upstream of the collapse, each one pumping seven million gallons of wastewater a day from the sewer line, into a contained section of the C & O Canal and then rerouted into the sewer pipe further downstream.  

Work is also underway to install the cofferdam which will contain the overflow in the canal, and to erect protective fencing around the area.  

DC Water urges the public to follow warning signs – which may include areas along the river further downstream - and avoid coming in contact with the overflow. People who contact raw sewage, may become sick and should take the following steps:

• Leave the area immediately.
• Wash exposed skin thoroughly with soap and clean water.
• Disinfect any affected areas or items.
• Do not consume food or water that may have been exposed.
• Seek medical attention if symptoms occur.
• Report exposure to DC Water at (202) 612-3400.

As a reminder there is no impact to drinking water. The sewer system and drinking water systems are separate and the overflow occurred downstream from the Washington Aqueduct’s intakes at Great Falls.  

The C & O Canal Towpath remains open, and no overflow has reached the towpath. However, people in the surrounding area may notice odors from the overflow. As work continues, one inbound lane of Clara Barton Parkway remains closed, just east of the 495 interchange.  

The Potomac Interceptor is a sanitary sewer system that handles up to 60 million gallons of wastewater every day from parts of Virgini and Maryland to DC Water’s Blue Plains Advanced Wastewater Treatment Plant. The collapse occurred late Monday, in a 72-inch diameter section of the pipe.

DC Water continues to work with our federal, state, and local partners to ensure public safety and monitor environmental impacts while we work to contain the overflow and begin repairs. Work is expected to continue through the weekend, even with the potential for heavy snow. Plans are in place to ensure plows are able to operate and crews can continue to install equipment and pumps for the bypass.  

Anyone with questions or in need of support can reach out to DC Water’s Customer Care team at (202) 354-3600 (Monday–Friday, 8 a.m. to 5 p.m.) or the 24-Hour Command Center at (202) 612-3400.