Nora Machine is one of the world’s most advanced tunnel-boring machines. Photo: NYC Water.
The DEP commences the largest repair project in the history of the New York City’s water system. The New York City Department of Environmental Protection has since 1992 been monitoring two leaking sections of the Delaware Aqueduct—one in the Orange County town of Newburgh, and the other in the Ulster County town of Wawarsing. The leaks release an estimated 20-30 million gallons of water per day. All of the data gathered shows that the leak rate has remained constant and the cracks have not worsened since DEP began monitoring the two leaks in 1992. In 2010, the City announced a plan to address the leaks by building a permanent 2.5 mile bypass tunnel around the leaking section of the aqueduct in Newburgh. The 2.5-mile bypass will be constructed 600 feet below the Hudson River—from Newburgh on the West Shore to Wappinger Falls on the East Shore.
The 85-mile Delaware Aqueduct is the longest tunnel in the world and supplies more than 500 million gallons of water per day to more than 9.5 million New Yorkers—approximately half of New York City’s drinking water. The $1 billion 2.5 mile bypass tunnel project is the largest repair project in the 175-year history of New York City’s drinking water supply system.
Work on the bypass tunnel began on September 8, 2017 and will continue 24 hours a day, five days a week for approximately 20 months. At this rate the tunnel should advance at the rate of about 50 feet of tunnel per day. The Delaware Aqueduct will stay in service while the bypass tunnel is under construction. Once the bypass tunnel is nearly complete the Delaware Aqueduct will be taken out of service and the bypass tunnel will be connected to structurally sound portions of the Delaware Aqueduct. The leaking sections will then be plugged and permanently taken out of service.
The six-month shutdown of the Delaware Aqueduct is planned to begin in October 2022. During the shutdown water supply augmentation and conservation measures via the City’s Croton and Catskill systems will provide a reliable supply of water to meet the needs of the City. The project is expected to be finished in 2023.
One of the world’s most advanced tunnel- boring machines will build the bypass tunnel. The tunnel-boring machine was named “NORA” in honor of Nora Stanton Blatch Deforest Barney, a suffragist and the first woman in the United States to earn a degree in civil engineering. “It is an honor for our grandmother, Nora, to lend her name to this unique tunnel boring machine,” said Coline Jenkins, the granddaughter of Nora Barney. “Both Nora and NORA are ground breakers, here to overcome obstacles and create a stronger society for millions of citizens.”
The DEP signed a project labor agreement in 2012 with the Hudson Valley Building and Construction Trade Council that promised that the vast majority of 200 jobs would be filled by local workers. The City expects to save up to $23 million. Under the project labor agreement which provides for a unified approach to shifts and time off, increased coordination, cost-effective scheduling and increased flexibility. The contract for the project was awarded as a joint venture. Kiewit-Shea Contractors was awarded the main $706 million contract for the underground construction of the bypass tunnel itself and Schiavone Construction was awarded a separate $101 million contract to construct entry shafts at both ends of the bypass tunnel.
Todd Diorio, President of the Hudson Valley Building and Construction Trades Council praised the project: “It takes care of the long overdue repairs to the water system supplying the City while at the same time creating hundreds of local construction jobs for members of the Hudson Valley Building and Construction Trades Council. This project will surely provide an economic boost to the local economy. I commend the City for its’ efforts to achieve the labor agreement.”
The bypass tunnel is the central component of DEP’s $1.5 billion Water for the Future program. “The start of tunneling to repair the Delaware Aqueduct is a major milestone in the history of New York City’s water supply system,” newly appointed DEP Commissioner Vincent Sapienza said, “Repairs approaching this magnitude have never before been attempted. The effort to fix the Delaware Aqueduct is by far the most complex repair DEP has ever undertaken, and it highlights the absolute need to keep our public works in a state of good repair.”
By: Thomas Columbia (Thomas is a student at New York Law School, Class of 2019).