The New York City Department of Environmental Protection is planning a $1.2 billion tunnel project starting at Kensico Reservoir that it said will mark the largest water supply tunneling effort in Westchester County since the 1940s.
The city DEP plans to dig a roughly two-mile-long tunnel from the Kensico Reservoir to a water treatment facility in Eastview. The project is expected to improve operational flexibility between the two facilities, which help provide the drinking water supply for more than 9 million people in New York City and Westchester.
Construction is still a ways off. The project will require a series of environmental reviews and permit approvals from federal, state, county, city and local agencies. DEP officials said in the announcement that the first elements of the tunnel construction will start in about five years. Work on the tunnel itself is expected to begin around 2025, with an estimated completion of 2035.
The work could create hundreds of jobs for local laborers, according to the announcement.
The tunnel will provide an additional connection between Kensico and Eastview’s Catskill-Delaware Ultraviolet Light Disinfection Facility, giving the DEP the ability to take other facilities out of service for maintenance and inspection.
DEP Commissioner Vincent Sapienza said the project represents “a critical investment in the long-term resiliency of New York City’s water supply system.” Westchester County Executive George Latimer, meanwhile, praised the opportunity for local jobs and said the tunnel project “is an example of how government can work effectively when we all work together.”
The reservoir and treatment facility are part of the largest unfiltered water supply system in the country, providing more than 1 billion gallons of water daily to more than 9.6 million New Yorkers.
Kensico Reservoir stores about 30 billion gallons of water at full capacity. About 1 billion gallons are drawn daily from the reservoir to meet the demand of New York City’s five boroughs and about 500,000 Westchester residents. That water is treated at the Catskill-Delaware Ultraviolet Light Disinfection Facility, which opened in 2012.
The tunnel is part of the DEP’s response to anticipated population growth in New York City and Westchester. It will stretch approximately 2 miles from an intake chamber on the western side of Kensico Reservoir to a connection point at the ultraviolet light disinfection facility. DEP expects the finished tunnel to measure approximately 27 feet in diameter and run 400-500 feet below ground. The tunnel will be large enough to carry a maximum of 2.6 billion gallons of water each day.