Traffic Advisory: Sewer Rehabilitation Project May Cause Temporary Delays on Clara Barton Parkway

October 17, 2025
Map of construction area on Clara Barton Parkway near I495
Updates Traffic Advisory issued Sept. 8, 2025, to reflect extended work noted in bold

Beginning September 8th, 2025, and continuing through October 10th, 2025, Clara Barton Parkway near the interchange with I-495/Beltway, will be reduced to one lane of traffic from 9:30 a.m. to 2:00 p.m. for a sanitary sewer rehabilitation project. The temporary lane closure is necessary to reline an 800-foot section of the sewer line, known as the Potomac Interceptor.

A temporary lane closure will be required in the same location to install a barrier wall for safety, construction equipment, and additional work on an as needed basis over the duration of the project. Construction is expected to be completed in Spring 2026.  

During construction, drivers may experience delays inbound on Clara Barton Parkway approaching the Beltway and through the work zone. The lane closure will begin prior to the I-495 Beltway ramp to the outer loop and continue just past the underpass. Access to both the inner and outer loop will remain available. Morning commuters traveling toward DC or to the I-495 Beltway are advised to plan for additional traffic and may want to consider alternate routes.

The Potomac Interceptor is a major sewer line that extends from the area around Washington Dulles International Airport to DC Water’s Blue Plains Advanced Wastewater Treatment Facility. The system carries 60 million gallons of wastewater daily from Virginia, Maryland, and DC.

Signage on Clara Barton Parkway will be posted to alert drivers of lane restrictions. DC Water appreciates your patience and cooperation as we complete this critical work to rehabilitate the Potomac Interceptor.

Visit dcwater.com to learn more about the Potomac Interceptor and the work underway to rehabilitate the 54-mile sewer line. This project is part of DC Water’s capital investment in infrastructure improvements to ensure safe, reliable sewer service and wastewater treatment for the region.

 

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