DC Water has successfully completed emergency repairs on a critical section of the Anacostia Force Main following a failure near Anacostia Avenue and Ponds Street Northeast in July. With repairs finalized, attention now turns to rehabilitating other vulnerable segments of the 6.25-mile pipeline to ensure long-term reliability and resilience.

The Anacostia Force Main is a vital piece of regional infrastructure, conveying approximately one-third of WSSC Water’s wastewater flow to DC Water’s Blue Plains Advanced Wastewater Treatment Facility. The pipeline has no redundancy, which means there is no way to reroute the wastewater if a break occurs nor enough storage to hold up to 200 million gallons per day of flow that may go through the force main during wet weather.

Any failure affects the entire pipe, making the aging pipe’s rehabilitation even more critical. This lack of redundancy will be further evaluated as part of future rehabilitation and capital improvement plans, to ensure future inspections and repairs can be carried out during periods of low or no flow. The collapse of the pipe underscored the urgency of addressing this vulnerability. 

“The Anacostia Force Main is a critical asset for both DC and Maryland,” said David L. Gadis, CEO and General Manager of DC Water. “Completing this repair quickly and safely was a major accomplishment, but it is just the beginning. Not only will it take technical expertise and coordination, but also significant financial investment to ensure the long-term reliability of this pipeline and the protection of public health and the environment.”

The initial emergency response and nearly two months of repair involved careful coordination between WSSC Water, National Park Service, and DC Water. Over the weekend, the final step to encase the repaired pipe with 72 cubic yards (144 tons) of concrete was completed allowing it to withstand the pressure inside. About a week prior, the two new pipe sections were sealed onto the opening with high pressure concrete allowing normal flow to resume and mitigating the risk of a sewer overflow.

DC Water is now accelerating plans to rehabilitate other sections of the Anacostia Force Main. This will provide stability and help prevent near-term failures while plans are developed for a more permanent solution. Drone inspections that took place during repair work showed accelerated degradation in the pipe. Those results and hydraulic modeling are being evaluated to identify those areas under stress or at risk of failure. Several rehabilitation strategies are being reviewed, carefully considering the site’s unique conditions and technical needs to ensure optimal performance and long-term resilience.

In the meantime, DC Water and WSSC Water will be evaluating long-term options, which could include building a second parallel pipe or other alternatives to replace or rehabilitate the existing pipe. This option would allow for periodic inspections and maintenance and also eliminate high points where the pipe rises and falls. These high points trap air, causing the pipe to wear down faster.

As DC Water pushes ahead with rehabilitation plans, crews have begun demobilizing the site, which will include removing the retaining wall panels, backfilling the excavation, and restoring landscaping and vegetation.

The rehabilitation of the Anacostia Force Main is part of DC Water’s 10-year, $9.6 billion Capital Improvement Program, supporting major capital investment in programs and projects to upgrade the water and sewer systems, provide safe, reliable service, build resiliency, and support a system that is equitable and sustainable. Learn more about our Capital Improvement Program at dcwater.com.