The New Croton Dam is a masonry gravity dam Designed by Alphonse Fteley (1837–1903), the masonry dam is broad at its base and high from base to crest. At the time of its completion, it was the tallest dam in the world. It impounds up to of water, a small fraction of the New York City water system's total storage capacity of .
History
thumb|left|The dam on the reservoir side
Background
The original Croton Dam (Old Croton Dam) was built between 1837 and 1842 to improve New York City's water supply. By 1881, after extensive repairs to the dam, which was high, the Old Croton Reservoir was able to supply about a day to the city via the Old Croton Aqueduct. To meet escalating water needs, the Aqueduct Commission of the City of New York ordered construction of a new Croton system in 1885. Hydro engineer James B. Francis was brought in as a consultant for the construction.
The proposed dam and reservoir were to cover of land occupied by public and private buildings, six cemeteries, and more than 400 farms.
Designed by Alphonse Fteley (1837–1903), the masony gravity dam is broad at its base and high from base to crest. At the time of its completion, it was the tallest dam in the world. The engineers' tablet mounted on the headhouse nearest the spillway lists the spillway length as and the total length of the dam and spillway combined as . New Croton Dam impounds up to of water, a small fraction of the New York City water system's total storage capacity of . downstream of the original dam, which was submerged by the new reservoir. New Croton Reservoir was eventually able to supply a day via a new aqueduct that carried water to Jerome Park Reservoir in the north Bronx, New York City.
Repair
thumb|New Croton Dam in 2016
The bridge over the spillway was replaced in 1975 and again in 2005. In that same year, because of the September 11 attacks on New York City, the New York City Department of Environmental Protection proposed permanent closure of the road across the top of the dam. Pedestrians and emergency vehicles were allowed to use New Croton Dam Road, but all other traffic was re-routed. The department made plans to replace temporary vehicle barriers with permanent barriers after completion of a New Croton Dam Rehabilitation Project in 2011.
Discharge Data
thumb|Water over the New Croton Dam spillway after [[Hurricane Ida in 2021 (average daily discharge 10,100 cubic feet per second)]]
U.S. Geological survey provides average daily discharge data for the Croton Dam here. Record discharge at the Croton Dam since records began in 1933 was on 1955-10-16 with 33,000 cfs (cubic feet per second); this was after dual hurricanes Connie and Diane.
Trails
left|thumb|upright|Old Croton Trail Endpoint
Croton Gorge Park offers views of the dam from directly downstream. The Old Croton Trail, a popular hiking and biking path that roughly follows the route of the Old Croton Aqueduct, has an endpoint near the base of the dam. Teatown Lake Reservation, a nature preserve, lies nearby as does Croton Point Park in Croton-on-Hudson.