Taken from on top of the New Croton Dam, the Croton River flows from there for about four miles until it enters the Hudson near Van Cortlandt Manor
According to Wikipedia the Croton River:
…is a river in southern New York that begins where its eastern and western tributaries join downstream from the Croton Falls Reservoir. Shortly downstream, the Croton River, along with its tributary, the Muscoot River, flows into the Muscoot Reservoir, after which it empties into the New Croton Reservoir, which feeds the New Croton Aqueduct supplying water to New York City. Excess water leaves the spillway at the New Croton Dam, and finally empties into the Hudson River at Croton-on-Hudson, New York at Croton Point, about 30 miles (50 km) north of New York City. The river has a watershed area of 361 square miles (930 km2).
I’ve taken pictures from this viewpoint before, but never produced one I was happy with. I rather like this one though: the way it’s mostly dark except for the silvery ribbon of water, intersected by bridge, which carries the road to the dam plaza.