 The construction of a new masonry dam in 1915, replaced the old dam, and expanded the water supply by bringing water from the Catskill Mountains over a distance of more than 100 miles.It is about 3 miles (5 km) north of downtown White Plains, New York, and about 15 miles (24 km) north of New York City.The reservoir serves mainly to store the waters received from the Catskill Mountains west of the Hudson River.