US Army Corps of Engineers
Baltimore District Website


McMillan Backwash Discharge to Sewer Environmental Assessment; May 2, 2019: Washington Aqueduct is proposing the construction of facilities for alternative treatment of filter backwash water at the McMillan Water Treatment Plan. The proposed action would allow WA to more effectively and safely accomplish its mission of providing high-quality drinking water in sufficient quantities to customers in the service area while meeting all regulatory requirements. Read the document here

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5900 MacArthur Boulevard
Washington, D.C. 20016-2514



Washington Aqueduct

The Washington Aqueduct produces drinking water for approximately one million citizens living, working, or visiting in the District of Columbia, Arlington County, Virginia, and other areas in northern Virginia to include portions of Fairfax County. 

A division of the Baltimore District, U.S. Army Corps of Engineers, the Aqueduct is a federally owned and operated public water supply agency that produces an average of 135 million gallons of water per day at two treatment plants located in the District of Columbia. All funding for operations, maintenance, and capital improvements comes from revenue generated by selling drinking water to the three jurisdictions.

The Corps of Engineers designed, built, and, in 1859, began operating the Aqueduct. Since then, the Corps has substantially expanded and improved the capacity and function of the Aqueduct from its original mission of supplying raw river water to a sparsely populated District of Columbia to today’s mission of providing safe drinking water to a much larger and more populous service area.

Our Mission

The mission of the Washington Aqueduct is to collect, purify, and pump an adequate supply of drinking water for its wholesale customers: DC Water, Arlington County, and Fairfax Water. 

Our Vision

Washington Aqueduct's vision is to be a leader in the water treatment and supply industry employing state of the art technology, highly-skilled and trained personnel, creative solutions and modern processes.