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Washington Aqueduct

U.S. Army Site

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Great Falls is the original intake for the Washington Aqueduct, the supply division of the District of Columbia water system. The Aqueduct facilities, built and operated by the U.S. Army Corps of Engineers, bring about 200 million gallons a day out of the Potomac, divert it through two conduits under MacArthur Boulevard, and treat it at the Dalecarlia and McMillan Water Treatment Plants. The original Aqueduct was built in the early 1860s by the Corps, and is still operated by the Corps. The city of Washington was served by a number of wells and springs for the first several decades of its existence. By 1802, the city was laying wooden pipes made of bored logs for supplying a few houses on Pennsylvania Avenue. But the main impetus for a reliable source of water for the city came from the need for adequate fire protection. Between 1832 and 1850, a number of studies for Congress indicated that springs and wells would not be adequate for the future growth and safety of the city. The British invasion of 1814 and burning of the White House had given evidence enough of that.

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Contact Information
U.S. Army Corps of Engineers
5900 MacArthur Blvd., N.W.
Washington DC 20016