Agreement to Manage Turbidity
Construction for Ashokan Reservoir. View of Olive Bridge dam
showing down-stream face of masonry section. Stone crusher
and concrete mixing plant in left background. June 21, 1910.
DEC and the New York City Department of Environmental Protection (NYCDEP) have agreed on an Order on Consent to manage turbidity and manage reservoir releases. This will improve water supply, water quality and habitat, and provide flood mitigation in the New York City watershed. The terms of the consent order also decrease the need for aluminum sulfate to be used in the Catskill Water Supply System.
Final Consent Order (PDF, 284 KB) - October 2013
Information About the Ashokan Reservoir
From New York City's Department of Environmental Protection: Located in Ulster County, about 13 miles west of Kingston and 73 miles north of New York City. Formed by the damming of the Esopus Creek. Consisting of two basins separated by a concrete dividing weir and roadway, it holds 122.9 billion gallons at full capacity and was placed into service in 1915. It is over 190' deep at its deepest point.
The Ashokan is one of two reservoirs in the City's Catskill Water Supply System. The other is the Schoharie, located 27 miles to the north, whose water flows into the Ashokan via the Shandaken Tunnel and the Esopus Creek. Including the water it receives from the Schoharie Reservoir, the Ashokan supplies about 40% of New York City's daily drinking water needs in non-drought periods. Water enters the Ashokan's West Basin and, after a settling period, is withdrawn from its East Basin. It is carried southeast under the Hudson River via the 92-mile Catskill Aqueduct, which has a maximum depth of 1,114 feet. It ordinarily enters the Kensico Reservoir in Westchester for further settling, where it mixes with Delaware system water and then travels south in two aqueducts before entering New York City's water supply distribution at the Hillview Reservoir in Yonkers, just north of the City line.
The Ashokan watershed's drainage basin is 255 miles and includes parts of 11 towns: Denning, Hardenburgh, Hurley, Kingston, Marbletown, Olive, Shandaken and Woodstock in Ulster County; Hunter and Lexington in Greene County and Middletown in Delaware County.