Watersheds

Did you know?

When you come to Great Falls Park, you are standing in two major watersheds.

The Potomac River is the second largest source of freshwater for the Chesapeake Bay. This 384 mile long river's watershed covers over 15,000 square miles. Four states and Washington D.C. drain into the Potomac. Tributaries include the Anacostia, Shenandoah, Occoquan, and Monocacy Rivers.

The Chesapeake Bay is the largest estuary in the United States, and boasts a watershed that covers over 64,000 square miles of land from New York to Virginia. Three rivers- the Susquehanna, the Potomac, and the James- provide 80 percent of the Bay's fresh water. Over sixteen million people live within the Bay's watershed.


 

What is a watershed?

All of the land that drains into a particular body of water. Some watersheds cover large areas of land. Road runoff in parts of New York and West Virginia, for example, will eventually flow into the Chesapeake Bay.

The health of a watershed is important to all of the plants, animals, and people who live within it. Migratory birds and fish depend on rivers and bays for food and shelter. People depend on a healthy watershed for recreation, drinking water, food, and their livelihoods.


 

Additional Information and Ways to Help

Chesapeake Bay Gateways Network- information, history, and places to visit along the Bay.

How Healthy is your Water?- local water quality information, volunteer opportunities, and ways you can help keep our water clean.

The Potomac Conservancy- Potomac River conservation and protection, with information on the river, maps, and volunteer opportunities.

Interstate Commission on the Potomac River Basin- water conservation information and ways to improve the health of the Potomac River.

Last updated: September 1, 2021

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Contact Info

Mailing Address:

Great Falls Park
c/o Turkey Run Park
George Washington Memorial Parkway

McLean, VA 22101

Phone:

703 757-3101
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