The Hillview Reservoir is a 90-acre (0.36 km2) storage reservoir in southeastern Yonkers, New York. It was built within a six-year period from 1909–1915 by the New York City Board of Water Supply to receive water from the newly constructed Catskill Aqueduct, which drained water from the Ashokan Reservoir and sent it down into the Kensico Reservoir, where it would, in turn, be drained back into a continuation of the Catskill Aqueduct, and sent into the Hillview Reservoir.