The Potomac River gathers water from parts of Maryland, Pennsylvania, Virginia, West Virginia, and the District of Columbia. This expanse of land (the Potomac’s watershed) plays an important role in river health. Small streams pass through forests and farms, towns and rural communities, and come together to form the Potomac River. Our actions on the land affect the health of our streams and the rivers they become. Often called “the Nation’s River,” the Potomac flows through Washington, D.C. and continues south to meet the Chesapeake Bay at Point Lookout, Maryland.
Visit our Snapshot of the Potomac Watershed page for some fast facts about the Potomac Watershed.
| Targeted Watersheds | |
| The Conservancy focuses on several priority sub-watersheds. Click on the river names below to learn more.
Cacapon River & Lost River Click here to see other maps of the watershed. |
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| Watershed Facts |
| River Miles: Main Stem: 383; Main stem plus major tributaries: 12,878.8 |
| Land Mass: 14,670 square miles (ICPRB) |
| Land Use: 57.6% forest, 31.8% agriculture, 5% water and wetlands, 4.8% developed (ICPRB) |
| Geologic Regions: Appalachian Plateau, Ridge & Valley, Blue Ridge, Piedmont Plateau, Coastal Plain |
| Major Tributaries: Anacostia River, Antietam Creek, Cacapon River, Catoctin Creek, Conococheague Creek, Monocacy River, North Branch, South Branch, Occoquan River, Savage River, Seneca Creek, and Shenandoah River |
| Population: 6.1 million in watershed (2010 estimated Census); 415.8 persons per square mile |
| Water Use: 486 million gallons withdrawn per day from Washington, D.C. area and 100 million gallons per day from rural areas (ICPRB, 2011). The Potomac River supplies almost 90% of DC metro area drinking water. |