DEP will build a two and one-half mile bypass tunnel around a portion of the aqueduct that is leaking in Roseton in Orange County, and repair other leaks in Wawarsing, in Ulster County, from the inside of the existing tunnel. The two and one-half mile bypass tunnel will run east from the Town of Newburgh in Orange County, under the Hudson River to the Town of Wappinger in Dutchess County, on the east side of the Hudson. The construction of the bypass tunnel and the repair of the lining will ensure that DEP can continue to deliver high quality drinking water every day for decades to come.
Beginning in 2013, the New York City DEP will construct new shafts in Newburgh and Wappinger to connect each end of the new bypass tunnel to the aqueduct. These shafts are vertical pipes that will be 700-900 feet deep with a diameter of 30’-35’. These shafts will not only connect to the bypass tunnel, but will also create access points for the construction of the bypass tunnel, which is slated to begin in 2015.
A tunnel boring machine will be used to create the bypass tunnel, which will be 22’ in diameter. When the bypass tunnel is completed, the existing aqueduct will be taken out of service and emptied. Then the bypass tunnel will be connected on both ends to the aqueduct and permanently replace the leaking section.
The tunnel will need to be shut down and emptied for a period of time to facilitate the bypass connection and perform the repair work. It will take between 6-15 months to complete repairs in the existing tunnel and connect the bypass tunnel to the aqueduct. Before the tunnel can be repaired, it must be shut down and emptied so that workers can access it and perform the repair work.