Delaware Aqueduct Rondout-West Branch Tunnel Repair Program

To address leaks in a portion of the aqueduct that connects the Rondout Reservoir in Ulster County to the West Branch Reservoir in Putnam County, the New York City Department of Environmental Protection decided to build a three-mile bypass tunnel while inspecting and rehabilitating the remainder of the aqueduct. AKRF led the environmental assessment and permitting efforts for the Delaware Aqueduct Rondout-West Branch Tunnel Repair Program in close coordination with the designated engineering team. Our preparation of the Environmental Impact Statement for the first phase of the program and the related federal, state, and local permits and approvals proceeded simultaneously to ensure the program remained on schedule. Construction of the bypass tunnel involves multiple geographic and jurisdictional challenges; complex project phasing; extensive permit and approval requirements; and detailed technical analyses in a number of environmental areas, including traffic, air quality, noise, visual impacts, and impacts to historic and natural resources.

The image above shows the start of tunneling for the Delaware Aqueduct Bypass Tunnel — the largest repair project in the 175-year history of New York City’s drinking water supply. Nora, the NYC DEP’s monumental tunnel boring machine, created this tunnel — 600 feet below the Hudson River. (Photo courtesy of Kristen Rendler, NYC DEP)

Nora, the DEP’s tunnel boring machine below the surface in Newburgh, NY | Photo courtesy of Kristen Rendler, NYC DEP

The 100-ton cutterhead for Nora is lowered down an 845-foot shaft | Photo courtesy of Kristen Rendler, NYC DEP

Steel liners for the bypass tunnel | Photo courtesy of Leah McWilliams, NYC DEP

Shaft 5b, 509 feet underground | Photo courtesy of Kristen Rendler, NYC DEP

Newsworthy

This is the largest repair project in the 175-year history of New York City’s drinking water supply.

WHAT WE DID
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