Pennsylvania’s water comes from several river basins. The three largest are the Delaware, Susquehanna, and Ohio River Basins. 

The Delaware River Basin starts in New York, extends into New Jersey, and continues into Delaware. It provides drinking water to 15 million people and contributes $25 billion annually in economic activity. 

The Susquehanna is part of the larger Chesapeake Bay watershed which includes New York, Maryland, Delaware, Virginia, West Virginia, and the District of Columbia. Rivers and streams that eventually flow into the Bay are the source of drinking water for 75% of the region’s 17 million residents.

The Ohio River Basin provides drinking water for more than three million people. It flows through or borders six states: Illinois, Indiana, Kentucky, Ohio, Pennsylvania, and West Virginia.

Each river basin is made up of thousands of smaller rivers and streams – so when pollution happens in one area, it can affect thousands of people for miles downstream. One of our top priorities is working with allies, lawmakers, and the governor’s office to protect Pennsylvania’s water sources that are vital to providing clean drinking water for families and wildlife. 

Pennsylvania's primary watersheds