The Delaware River Basin extends to the Catskill Mountains in New York State and stretches more than 330 miles through four states and 42 counties before draining through the Delaware Estuary to the Atlantic Ocean. Philadelphia’s entire land surface ultimately drains to one of seven watersheds that are tributaries to the Delaware River.
Watershed Fast Facts
The entire watershed drains nearly 13,000 square miles, of which Philadelphia’s contribution is very small. Approximately 40 square miles of the City of Philadelphia drain directly to the Delaware River.
The Delaware River Watershed contains approximately 23,700 linear miles of streams. Again, the City of Philadelphia’s contribution is very small, limited to 21 miles of the Delaware River waterfront.
Estimated at approximately 7.7 million residents, approximately 500,000 live in the City of Philadelphia.
Land Use/Impervious Cover
Land use is estimated to be approximately 55% forest, 15% developed, and 26% agriculture throughout the entire watershed. The area within Philadelphia is very densely developed and estimated to be 72% impervious surface.
The Delaware River watershed encompasses areas of four states, 42 counties and all or parts of 838 municipalities in the Mid-Atlantic region.
Help protect your watershed!
Aquatic wildlife markers are an easy way to remind your neighborhood to keep trash and chemicals out of drains.