This area is also called the Potomac watershed. It includes all of the land area where water drains towards the mouth of the Potomac – the point where the river spills into the Chesapeake Bay. The Potomac basin is the 2nd largest watershed in the Chesapeake Bay watershed.

The Potomac River brings together a variety of cultures throughout the watershed from the coal miners of upstream West Virginia to the urban residents of the nation's capital and, along the lower Potomac, the watermen of Virginia's Northern Neck.

Use this interactive map to explore sub-watersheds of the Potomac River basin. Click on a watershed to view more information. Potomac basin map showing land use data from 2021 NLCD. Expected percent change in water withdrawals from 2025 …

Interactive Potomac River Basin Atlas with no header. This map features the subbasins (HUC 8), watersheds (HUC10), and subwatersheds (HUC12) of the Potomac River basin.

Watershed Address from Headwaters to Mouth: The Potomac flows from Fairfax Stone, West Virginia, to Point Lookout, Maryland, and into the Atlantic Ocean.

Its watershed of 14,670 square miles is nearly 60 percent forest, qualifying it as one of the most forested in the country. It provides critical habitat for wildlife and multiple species of fish while offering the nation’s capital a place to play.

The Potomac Watershed Partnership (PWP) is a collaborative effort among federal, state, and local partners to restore the health of the land and waters of the Potomac River Basin, thereby enhancing the quality of life and overall health of the Chesapeake Bay.

A collection of maps relevant to source water protection in the Potomac River Basin, including watersheds, sub-watersheds, and HAB monitoring locations.

Pennsylvania is important to the watershed because many headwater streams that contribute to the Potomac or the Monocacy River form in one of seven counties in southcentral Pennsylvania. The Potomac River’s entire basin encompasses 14,670 square miles over four states: Pennsylvania, Virginia, Maryland and West Virginia, and the District of ...

Dec 7, 2022 · The Potomac River is 652 km (405 miles) in length and has a drainage basin of 38,000 km 2 (14,700 square miles), which makes it the fourth largest river on the United States’ Atlantic Coast. It runs from Fairfax Stone, West Virginia to Chesapeak Bay. The Potomac River map shows the Potomac watershed. Major Features