University gives update on installation of pipes for Lake Source Cooling

The sections of the intake piping for the Lake Source Cooling project float in Cayuga Lake near Portland Point Oct. 1 waiting for deployment activities. During the week, the sections are being pulled up the lake, positioned and submerged to their final locations on the lake bottom. Robert Barker/University Photography

Over the next few weeks, Cornell and its contractor, Stolt Comex Seaway, will position piping in Cayuga Lake for the Lake Source Cooling project. This operation will be the culmination of construction during the summer and fall that will end with the last step of installing the piping on the lake bottom.

Preparation work for laying the lake piping has been ongoing since early summer. The plastic piping, made from high density polyethylene, were assembled into large lengths of 1,200 to 2,000 feet in the water at the assembly area near Portland Point on the east shore of the lake. Concrete weights and ductile iron stiffener rings were fabricated and installed on the outside of the pipe to provide ballast and stiffening for the plastic in the water.

Dredging of the shallow lake bottom near shore, now almost complete, is necessary to place the pipe below the lake bottom for safe boating clearance. The dredging is being performed inside special protective barriers to prevent muddy water from escaping the work area and to keep boaters safely separated from construction activities.

The pipe-laying operation is occurring in steps. First, the large segments are being brought up the lake from Portland Point to the areas directly over their final path, and then lowered in a "controlled sinking" operation to their resting spot on the lake bottom.

Starting from the shore end, each pipe segment is flooded with water in a controlled manner and connected to the next segment, eventually forming a continuous 10,400-foot intake that ends in 250 feet of water. The outfall pipe is much shorter, extending about 500 feet into the lake to a depth of about 14 feet.

Nearly half of the intake pipe, a length of over 5,000 feet, requires the use of a large pull barge. In addition to this barge, a number of other barges and boats are on the lake to support the deployment process.

At all times during operations on the lake, safety of the public is the highest priority. Stolt Comex Seaway has informed the Tompkins County Sheriff's department, the Coast Guard Auxilliary, the Ithaca Yacht Club and local tour boats of all planned activities. Signs are up in all of the local marinas. In addition, Stolt Comex Seaway is monitoring all work areas with patrol boats to keep the public at a safe distance. All structures on the lake have lights for night visibility.

All of the preparation work and pipeline-laying activities are being done in careful compliance with regulations and authorizations of the New York State Department of Environmental Conservation (NYSDEC), the New York State Office of General Services and the United States Army Corps of Engineers.

The Lake Source Cooling project underwent a four-year review and approval process that resulted in a Final Environmental Impact Statement. Approved in January 1998, it presented an analysis of lake source cooling and any potential impact it would have on Cayuga Lake. The findings of the NYSDEC, as lead agency for the environmental review, stated that the project "minimizes or avoids adverse environmental effects to the greatest extent practicable" and that it would benefit the environment by reducing the combustion of fossil fuels in regional power plants.

There is a Lake Source Cooling project web site at http://www.utilities.cornell.edu/lsc.