The Delaware River is the longest Un-dammed river east of the Mississippi, extending 330 miles from the confluence of its East and West branches in New York State to the mouth of the Delaware Bay where it meets the Atlantic Ocean.  The Delaware Estuary, the tidal portion of the river as well as the bay, stretches 133 miles from Trenton, NJ to Cape May, NJ and Lewes, Del.  Three quarters of the Delaware River - a 150 mile reach from Hancock, NY to Trenton, NJ - has been included in the National Wild and Scenic Rivers System. According to the National Park Service, this "wild and scenic" designation is a distinction belonging to less than one-half of one percent of the nation's 3.5 million miles of rivers.

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The Delaware River Basin comprises the 13,539 square mile watershed that drains to the Delaware River including portions of four states, Delaware, New Jersey, New York and Pennsylvania. There are 216 tributary streams and creeks—an estimated 14,057 miles of streams and creeks—in the watershed. While the watershed is home to 4.17 million people according to the 2000 Federal Census, these bodies of water provide drinking water to 17 million people—roughly 6% of the population of the United States.The waters of the Delaware River's basin are used to sustain "fishing, transportation, power, cooling, recreation, and other industrial and residential purposes." It is the 33rd largest river in the United States in terms of flow, but one of the nation's most heavily used rivers in daily volume of tonnage. The average annual flow rate of the Delaware is 11,700 cubic feet per second at Trenton, New Jersey. With no dams or impediments on the river's main stem, the Delaware is one of the few remaining large free-flowing rivers in the United States.

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Water quality in the Delaware River Watershed is very good in many respects. Most of the water quality concerns in the watershed are associated with the protection of the quality of the waters of the New York City water supply reservoirs rather than current impacts or impairments in the watershed. Currently there are only five water bodies in the watershed that are considered to have impaired uses. These impairments are largely the result of atmospheric deposition of pollutants - mercury and acid rain - from outside the watershed.

The clean, clear waters of the River’s upper and middle reaches and its cold tributary streams support a wilder landscape rich in fish and wildlife where residents enjoy a more rural way of life. It is also where the visually stunning Delaware Water Gap lies. Every year, millions of visitors take advantage of the wide range of recreational opportunities it offers. Hard to believe it’s just 90 minutes from the heart of New York City. The lower end of the River and its Estuary host the world’s largest horseshoe crab population and an active commercial fishery, yet are marked by heavy industry and busy shipping traffic. The Delaware River Port Complex (including facilities in New Jersey, Pennsylvania and Delaware) is the largest freshwater port in the world and is the largest for steel and paper in North America. The Port is the East Coast’s largest importer of cocoa beans and fruit and as much as seventy percent of the oil shipped to the Atlantic Coast moves through the Estuary.