NORWALK, Conn. (AP) – A massive cable-laying ship, rising high above Long Island Sound halfway between Connecticut and New York, is at rest after wrapping up its work stringing miles of electrical cables along the seabed.

The new cables are now being buried beneath the Sound’s floor, completing most of the project that replaced aging, battered cables along an 11-mile stretch between Norwalk and Northport, N.Y.

The previous cables, which were unreeled along the bottom of the Sound in 1969, were damaged over the decades by anchors and ships, causing periodic power interruptions and leaking oil used as insulation. Connecticut Light & Power and the Long Island Power Authority, partners in the $140 million replacement project, are using new technology to bury the cables as much as 6 feet below the seabed, which in places is as deep as 200 feet.

The cables, which can transmit 300 megawatts of power, will supply power to New England and New York to relieve stress on regional power grids that typically occur during stretches of blistering summer days when electricity is at a premium.

“It’s like a mutual aid facility,” said CL&P spokesman Frank Poirot, who ferried reporters to the Skagerrak, the Norwegian ship doing the project’s heavy lifting.

The power capacity is relatively small – the record for electricity use in New England was more than 28,000 megawatts on Aug. 2, 2006. Still, it represents about half the electricity put out by a typical power plant.

“This increases our flexibility in operating the power system and provides for additional sources of power, especially in times of emergencies,” said Erin O’Brien, spokeswoman for ISO-New England, operator of the regional grid.

CL&P is spearheading other projects to keep up with rapidly rising demand for electricity. Increasingly widespread use of central air conditioning, computers, multiple-TV households and the burgeoning use of other appliances are stressing aging power systems, particularly in highly populated Fairfield County.

Other CL&P upgrades are a 21-mile transmission line between Bethel and Norwalk that was completed in 2006, a 69-mile, $1 billion transmission line being built from Middletown to Norwalk and installation of an underground transmission line in southwest Connecticut.

Michael Deering, vice president for environmental affairs at the Long Island Power Authority, touted the cable project’s environmental benefits, saying it will have a lighter impact on Long Island Sound than the power lines that were removed.

“It’s significantly more environmentally beneficial,” he said.

The defunct 39-year-old cables were filled with nontoxic insulating fluid that leaked, threatening the Sound. The new cables are solid and not susceptible to leaks, according to CL&P and the Connecticut Department of Environmental Protection.

“We hope these cables will never be hit,” said Jeffrey Martin, CL&P’s manager for the Long Island Sound cable project. “But if so, no fluid will be released into the Sound.”

And burying the cables provides additional protection not available in 1969, he said. A submersible vehicle blasts water into the sediment at the bottom of the Sound, clearing an area to drop thousands of tons of cable. Rising power demand worldwide is keeping the Skagerrak busy.

Owned by Nexans, an Oslo, Norway-based manufacturer and installer of electrical, telecommunications, industrial and other cables, the Skagerrak is one of only a few ships in the world that can carry as much as 7,000 tons of cable. After returning to Norway to pick up another load of cables, it next heads to Abu Dhabi in the Persian Gulf and then China.

“Our market could be increased demand for power on an island somewhere or cross-sound like in New York or it could be electrification of an offshore industry here in the North Sea and everywhere else in the world,” said Krister Granlie, deputy vice president at Nexans.

The Skagerrak’s crew has finished laying the cables, which now join another power line, a gas pipeline and two telecommunications cables, all crisscrossing Long Island Sound.

Most of the CL&P-LIPA transmission line is being buried now on the Connecticut side, while New York regulations require CL&P to begin and finish burial on the New York side in early May, Martin said. Work in winter and early spring will avoid disruptions to oyster beds on the Connecticut side of the Sound and flounder on the New York side.

The cable is scheduled for testing in June and is expected to be activated in July.

“It will be nice to see this happening,” Martin said.

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On the Net:

www.cl-p.com

www.lipower.org

www.nexans.com

AP-ES-03-01-08 1436EST

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