Undammed
The main stem of the Delaware is the longest free-flowing (undammed) river east of the Mississippi. Tributary river flows are controlled by upstream reservoirs operated by the City of New York. Under a 1954 Decree signed by the United States Supreme Court, in times of normal precipitation and runoff, the average daily flow at the northernmost river gauge in Montague, New Jersey must be maintained at 1,750 cubic feet per second.
Archeologists have found remains of prehistoric human settlements on the Delaware River dating back 10,000 years or more. Lenni Lenape Native American tribes appeared some 4,000 years ago. The first lasting settlement on the Upper Delaware River was started at Cushetunk around 1750 by Connecticut residents in search of land ownership.