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Managing the Rehabilitation of a Critical Sanitary Sewer in Washington, DC

Managing the Rehabilitation of a Critical Sanitary Sewer in Washington, DC

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DC

The Potomac Interceptor Program will ensure reliable wastewater conveyance, safeguard the environment and protect community health. 

Last year, the DC Water Board approved a $40.35 million contract with TYLin for the management and rehabilitation of the Potomac Interceptor. Constructed in the 1960s, this 54+ mile sanitary sewer serves communities in Fairfax and Loudon Counties, VA (including the Town of Vienna, Herndon and Washington Dulles International Airport and Montgomery Country, MD. 

The sewer carries approximately 60 million gallons of wastewater daily to the Potomac Pumping Station in Washington, DC, and then onwards to the Blue Plains Wastewater Treatment Plant. Ranging from 36” to 96” in diameter, and including 11 tunnel sections and 2 river crossings, this complex piece of infrastructure has been essential to the growth of the Maryland and Virginia suburbs, as well as protecting the Potomac River from water pollution. Ongoing internal inspections of the Interceptor have found significant pipe deficiencies and substantial corrosion in selected sections; a failure of the pipe could jeopardize DC Water’s ability to serve surrounding communities, and risk contamination of the Potomac.

potomac rehab

TYLin is already at work investigating and rehabilitating tens of thousands of feet of the most vulnerable sections of the Interceptor. The firm is also developing plans for operations and management, emergency response, and the long-term resiliency of the sewer. 

Later in January, TYLin will conduct rock borings adjacent to the pipe near Great Falls Park, one of the two crossings of the Potomac River. This effort, which will involve lifting a drill rig and workers into place via helicopter, within view of one of the region’s most iconic natural attractions, will present a highly visible opportunity for DC Water to engage with the public.

The award of this contract is a supplemental agreement to TYLin’s highly regarded work on DC Water’s Clean Rivers Project. As Program Manager for this $3 billion slate of capital improvements, TYLin is helping DC Water meet its goals of reducing sewer overflows by 96%, mitigating flood risk, and reducing nitrogen discharge to Chesapeake Bay by approximately 1 million pounds per year.

“We’re honored to be partnering with DC Water on this essential project,” said Eric Lienhard, Deputy Program Manager of TYLin’s Clean Rivers team. “Building on our longstanding work maintaining and enhancing the region’s  infrastructure, the rehabilitation of the Potomac Interceptor will continue to provide DC Water’s Joint Use Partner communities reliable wastewater conveyance while safeguarding the river  helping to protect the health of communities across the Washington metropolitan area for years to come.”

Learn more about TYLin’s work on wastewater systems.

Eric



Meet Eric Lienhard

With over three decades of experience in water and wastewater engineering, Eric has extensive expertise in the planning, design, and construction of wastewater treatment plant upgrades, collection system improvements, and combined sewer overflow (CSO) reduction projects. Currently, Eric serves as the Deputy Program Manager for the award-winning $3 billion DC Water Clean Rivers Program, a critical initiative aimed at addressing CSOs in the Nation's Capital.

In his role, Eric leads the program team in the rehabilitation of the Potomac Interceptor, a 54-mile sanitary sewer system that transports over 60 million gallons per day (MGD) of dry weather flow from Dulles International Airport to the DC Water Blue Plains Wastewater Treatment Plant. This system serves Joint Use customers in both Virginia and Maryland.

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