The Delaware River is the longest undammed river east of the Mississippi, and its Upper, Middle, and Lower segments flow unimpeded 330 miles from Hancock, New York, to the Delaware Bay. Congress designated the Middle Delaware National Scenic and Recreational River in 1978 under the Wild and Scenic Rivers Act, which preserves rivers throughout the United States for their wild, scenic, and recreational attributes. Designated rivers must be free-flowing and have excellent water quality, and these qualities in the Middle Delaware protect clean drinking water, maintain high ecological integrity, and ensure superior recreational experiences. The defeat of the Tocks Island Dam in 1975 was an early victory for the environmental movement, and American shad can freely migrate up the Delaware River from the bay in spring.
