Anacostia River
Watershed Characterization

The Anacostia watershed covers about 178 square miles with a drainage area that is 49% in Prince George’s County, Maryland, 34% in Montgomery County, Maryland, and 17% in the District of Columbia. About two thirds of the watershed is characterized by Coastal Plain and the remaining is in the Piedmont province. The mainstem of the river is tidal throughout the District of Columbia. The head of tide in the Anacostia River mainstem is just outside of the District in the vicinity of Bladensburg in Prince George’s County. The Bladensburg vicinity is also where the two major branches of the non-tidal Anacostia River, the Northeast Branch and the Northwest Branch, have their confluence.

Prince George’s County is receiving a Federal grant to prepare a Watershed Restoration Action Strategy (WRAS) for its portion of the Anacostia River Watershed. As part of the WRAS project, the Maryland Department of Natural Resources (DNR) is providing technical assistance, including preparation of a watershed characterization (compilation of available water quality and natural resources information and identification of issues), a stream corridor assessment (uses field data to catalog issues and rate severity) and a synoptic survey (analyzes benthic macroinvertebrates, fish and water samples with focus on nutrients). The County will consider the information generated in these efforts as it drafts the County Watershed Restoration Action Strategy.

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