UPDATE: Pumps are in Place and DC Water is Reinforcing Receiving Section of Potomac Interceptor to Complete Bypass

January 23, 2026
Three pumps installed as part of the bypass system

Today, DC Water and its contractors continued the installation of six high-powered pumps that will be used to reroute wastewater around a collapsed section of the Potomac Interceptor along Clara Barton Parkway in Montgomery County, MD and the C & O Canal National Historic Park.

The Potomac Interceptor is a sanitary sewer line that conveys up to 60 million gallons of wastewater every day from parts of Virginia 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 causing millions of gallons of wastewater to overflow.

The pumps are part of a bypass that will divert the flow around the damaged section of the Potomac Interceptor, to contain the overflow and allow excavation and repairs to begin. The pumps are positioned upstream of the collapse, each one having the capability to pump up to seven million gallons of wastewater a day from the sewer line, into an isolated section of the C & O Canal and then rerouted into the sewer pipe further downstream of the collapse. 

The pumps will be ready to be turned on once the supporting work is completed to prepare the bypass for operation. Crews are currently reinforcing the receiving section of pipe downstream of the collapse to ensure it has the structural capacity to handle the flow once the bypass is activated. Engineers anticipate turning the pumps on gradually the evening of Monday, January 26, and to have the bypass potentially operating at full capacity on Tuesday, January 27, weather permitting.

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 I-495 interchange. 

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.

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