The Kensico Reservoir is a reservoir located in the towns of Armonk (North Castle) and Valhalla (Mount Pleasant), New York. It was formed by the old earth and gravel dam, built in 1885, which impounded waters from the Bronx and Byram rivers, and supplied about 18 million gallons daily. 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. Along with the West Branch Reservoir and Boyds Corner Reservoir, it is one of only three reservoirs within the Catskill/Delaware system outside the Catskill Mountains region.
Before constructing the existing Kensico Dam, the old Kensico Dam had to be removed; this began in 1911. The construction of the dam began in 1913 and was concluded in 1917—three years ahead of schedule—at a cost of more than $15,000,000. The dam is 1,843 feet (562 m) long. It stands 307 feet (94 m) above its foundation and contains 1 million cubic feet (28,000 m3) of masonry—as much masonry as the Egyptians used to build some of the pyramids. In one month, 2.5 million cubic yards of concrete were poured into blocks, which had to cure for three months before being swung onto the rising hyperbolic pile of dam. The dam is able to hold back about 30 billion US gallons (110,000,000 m3) of water.
Frank E. Winsor was the engineer in charge of construction of Kensico as well as Hillview Reservoir and 32 miles (51 km) of the Catskill Aqueduct.
New York City’s main contractor built a work camp at nearby Valhalla for the 1,500 men who worked on the dam at the height of construction. The water supply board created a mounted police force to keep order. Crews were largely made up of Italian immigrants, who began the long task of digging straight down to a depth of 110 feet (34 m) to reach solid rock with no water-bearing seams. This entailed months of blasting and a number of fatal accidents. As the aqueduct neared completion in 1913, the work gangs at Kensico began laying the first of the concrete bricks of which the dam is built.
The tremendous influx of workers provided a period of prosperity for the surrounding area. New stores, rooming houses, hotels, restaurants and saloons met the needs of the workers and their families. Many of the construction families remained in the area after completion of the dam, contributing to the growth and character of Valhalla and its environs. The Kensico Reservoir was acquired as parkland in 1963 from the New York City Watershed Commission and remains the property of the New York City Department of Environmental Protection. Kensico Dam Plaza is a Westchester County Park. More details
Before constructing the existing Kensico Dam, the old Kensico Dam had to be removed; this began in 1911. The construction of the dam began in 1913 and was concluded in 1917—three years ahead of schedule—at a cost of more than $15,000,000. The dam is 1,843 feet (562 m) long. It stands 307 feet (94 m) above its foundation and contains 1 million cubic feet (28,000 m3) of masonry—as much masonry as the Egyptians used to build some of the pyramids. In one month, 2.5 million cubic yards of concrete were poured into blocks, which had to cure for three months before being swung onto the rising hyperbolic pile of dam. The dam is able to hold back about 30 billion US gallons (110,000,000 m3) of water.
Frank E. Winsor was the engineer in charge of construction of Kensico as well as Hillview Reservoir and 32 miles (51 km) of the Catskill Aqueduct.
New York City’s main contractor built a work camp at nearby Valhalla for the 1,500 men who worked on the dam at the height of construction. The water supply board created a mounted police force to keep order. Crews were largely made up of Italian immigrants, who began the long task of digging straight down to a depth of 110 feet (34 m) to reach solid rock with no water-bearing seams. This entailed months of blasting and a number of fatal accidents. As the aqueduct neared completion in 1913, the work gangs at Kensico began laying the first of the concrete bricks of which the dam is built.
