The U.S. Army Corps of Engineers, Baltimore District’s Potomac and Anacostia Rivers Drift Collection and Removal Unit operates out of dock facilities adjacent to the Washington, DC, Navy Yard and conducts drift removal operations on a year-round basis.
Known as "DC Drift," the mission covers 27 miles of waterways. USACE boat operators conduct routine patrols and respond to calls received from the Coast Guard, Navy, boat and marina operators, and private citizens.
Their mission also includes the operation and maintenance of the inlet and outlet gates to the tidal basin, which is designed to prevent water stagnating in the tidal basin by allowing fresh water to flow in and out of the basin.
The basin, constructed between 1882 and 1909, was designed to be a visual centerpiece and a means to flush out the Washington Channel. The reservoir releases 250-million gallons of water captured at high tide twice a day, flushing the channel free of sediments and impurities. The outlet bridge was completed in 1889 and the inlet bridge two decades later in 1909.