The New York City Department of Environmental Protection (DEP) has commenced the $1.9 billion Kensico-Eastview Connection (KEC) tunneling and facilities upgrade project in Mt. Pleasant, Westchester County. This project aims to enhance the operational flexibility of the drinking water supply system serving over 9 million residents in New York City and southern Westchester County. It represents the city's largest water-supply tunneling initiative in Westchester since the 1940s and is expected to create hundreds of local jobs.
Enhancing water supply reliability
The KEC project features a two-mile-long tunnel connecting Kensico Reservoir to the Catskill-Delaware Ultraviolet Light Disinfection Facility (CDUV) in Eastview. This new tunnel will allow the DEP to conduct maintenance and inspections on other facilities without disrupting water service. "Creating additional redundancy in our vital water supply system is an essential investment for the long-term resilience of the remarkable feat of engineering that provides more than 9 million New Yorkers with a reliable supply of pristine tap water," said DEP Commissioner Rohit T. Aggarwala.
Project phases and timeline
The initial phase of construction involves site preparation at the DEP campus near Kensico Reservoir, followed by the excavation of two large shafts, each 400-500 feet deep. The subsequent phases will involve tunneling between the shafts and constructing new facilities and upgrades at the Kensico campus. The entire project is slated to take ten years, with the tunnel becoming fully operational by 2035.
Kensico Reservoir
Situated north of White Plains, Kensico Reservoir is a critical part of New York City’s Catskill-Delaware Water Supply System, storing up to 30 billion gallons of water. The DEP draws about 1 billion gallons daily from Kensico to meet the needs of New York City and approximately 500,000 residents in Westchester County. Water from Kensico is treated at CDUV, the largest ultraviolet disinfection facility in the world.
Tunnel specifications and future planning
The KEC tunnel will span approximately two miles from Kensico Reservoir to CDUV, measuring 27 feet in diameter and positioned 400-500 feet below ground. It will have the capacity to transport up to 2.6 billion gallons of water daily, designed to accommodate future growth in the city and Westchester County, and facilitate maintenance activities on other infrastructure.
Additional facilities and upgrades
The project also includes significant improvements at both Kensico Reservoir and CDUV. Upgrades will be made to a century-old intake chamber at Kensico to ensure efficient water draw into the new tunnel, alongside shoreline enhancements to prevent sediment contamination. Additionally, the Kensico campus will see utility, grading, and drainage upgrades. A new screen chamber will be built to remove debris from the water, and chemical addition systems will be upgraded for continued proper water treatment.
At CDUV, a connection chamber will be constructed to receive water from the new tunnel, complemented by drainage, stormwater, and utility improvements at the site.
Historical context and future projects
Built in 1915 and later modified in the 1940s, Kensico Reservoir is integral to New York City’s Catskill-Delaware System, the largest unfiltered water supply in the United States. In addition to the KEC project, the DEP plans to initiate over $1 billion in facility and infrastructure enhancements at Hillview Reservoir in Yonkers, the final stop for Catskill water before it enters the tunnels supplying the five boroughs.
