West Branch Delaware River

The West Branch Delaware River is one of two branches that form the Delaware River. It is approximately 90 mi long, and flows through the U.S. states of New York and Pennsylvania. It winds through a mountainous area of New York in the western Catskill Mountains for most of its course, before joining the East Branch along the northeast border of Pennsylvania with New York. Midway or so it is empounded by the Cannonsville Dam to form the Cannonsville Reservoir, both part of the New York City water supply system for delivering drinking water to the City.
It rises in Schoharie County, New York and flows generally southwest, entering Delaware County and flowing past Stamford and Delhi. In southwestern Delaware County it flows in an increasingly winding course through the mountains, generally southwest. At Stilesville it is impounded to form the Cannonsville Reservoir. At Deposit, on the border between Broome and Delaware counties, it turns sharply to the southeast and is paralleled by New York State Route 17. It joins the East Branch at Hancock to form the Delaware. For the lower 6 mi it forms part of the boundary between New York and Pennsylvania.

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