Nova Scotia Power starts install of new power lines across Strait of Canso

Nova Scotia Power has started to install high-voltage power lines across the Strait of Canso.

The lines are a requirement of the Maritime Link project and will also serve as a backup power connection to Cape Breton Island.

"This is a very critical crossing," said Tom Flewwelling, a senior project engineer with NSP.

"If there was ever a tower fault, such as a lightning strike, along with the additional power flows from the Maritime Link, and we were to lose these lines, then we would lose the backbone to our system."

The new 345 kV overhead crossing is about 45 metres south of the existing crossing and consists of six towers and six high-voltage transmission lines.

Flewwelling said the installation requires different types of equipment to pull and keep tension on the lines to the appropriate height across water and land.

"This is a very large specialized conductor which has a diameter of roughly two inches," he said. "It's six tonnes per kilometre and the span across the Strait of Canso is three kilometers."

To allow for the install, marine traffic will be restricted between now and Dec. 22.

"Because of safety concerns, marine traffic will not be able to go underneath the conductor while we are pulling it," Flewwelling said.

Ships will have to wait until the line is secure and then a tug boat will direct it under the line. On Thursday, a barge was delayed for a short time.

The operator of the Martin Marietta quarry at the Canso Causeway said it is not expecting problems or serious delays.

Work will wrap up for the year on Dec. 22, and crews will resume work at the site sometime in January.

Flewwelling said he expects the new line to be transmitting power by the end of January.