October 2, 2000

Contact: Geoff Ryan (718/595-6600)

New York City To Repair Valve At Shaft 6 In Chelsea

A gate valve at Shaft 6 of the Delaware Aqueduct will be repaired, starting in late November, according to an announcement by Commissioner Joel A. Miele Sr., P.E., of the New York City Department of Environmental Protection (DEP). The shaft is located at the same site as the City's Chelsea Pumping Station, near the Newburgh-Beacon Bridge on the east side of the Hudson River. The job is scheduled to start on November 28, with repair crews on-site and working round the clock for up to ten days.

The function of Shaft 6 is to serve as a de-watering apparatus for the Delaware Aqueduct. Once the gate valve itself is repaired, DEP plans to have an inspection team examine the Aqueduct's condition, ascertain the extent and type of any other leaks, and make recommendations for future maintenance and repair efforts. DEP is aware of two existing leaks in the Aqueduct; both are west of the Hudson, one in Roseton and the other in Wawarsing.

In commenting on the leaks, Commissioner Miele said, "The repair of the gate valve at Shaft 6 is the first step in dealing with those leaks. We have known about them for some time and have been developing plans to correct the leaks, which may be due to underground geological conditions that existed when the Aqueduct - a deep rock tunnel - was built in the 1940s. While we are convinced the leaks do not represent a threat to the safety and reliability of the Aqueduct at present, we believe the time to take corrective action is now. Accordingly, we are taking aggressive actions to locate and fix the leaks, including use of a remotely controlled underwater vehicle to inspect and photograph the interior of the tunnel. This vehicle is now being custom built for DEP by the Woods Hole Oceanographic Institute."

While the gate valve is under repair, water will not flow through the tunnel. The Town of Marlborough and the City of Newburgh, which withdraw water from the Delaware Aqueduct, have been advised of the temporary shutdown and will be able to utilize their other sources of water without any interruption of service.