More repairs needed for Muskrat Falls lines, but clearing access roads will take weeks

More repairs are needed on the Muskrat Falls hydroelectric project's transmission lines, with equipment failures due to "extreme weather" reported on eight towers in a remote area of Newfoundland.

Newfoundland and Labrador Hydro said Wednesday that "minor damage," affecting communications but not power transmission, was discovered Feb. 10 following a "recent icing event."

It said "some preliminary work" has been completed to secure the damaged towers, but that the bulk of repairs hadn't begun because dozens of kilometres of isolated access roads need to be cleared first.

"This particular issue was identified on Feb. 10 following a period of heavy ice conditions in an area approximately 25 kilometres west of the town of Terra Nova. The area is known to our teams for extreme weather," Hydro spokesperson Jill Pitcher said in a written statement.

"The steel frame at the very top of the tower (towers vary in height, but on essentially the top 10-15 per cent of the affected tower) where our communications cables attach were bent under the weight of the ice. An investigation is ongoing and will give us more information."

Snow clearing began on Feb. 16. About a dozen workers have been using heavy equipment to clear access roads connecting the towns of Terra Nova and Gambo to the damaged section of the Labrador-Island Link (LIL) transmission line.

Fully clearing several dozen kilometres of remote roads — the only way to get equipment to the site and repair the damaged equipment — could take about a month, according to Farrell's Excavating, the contractor in charge of the operation.

But enough plowing has been done to begin the first repairs Thursday, according to Hydro.

No one at N.L. Hydro was available for an interview Wednesday. Pitcher did not provide a timeline or cost for completing the work, but said "we will know more about how long repairs will take once work gets underway."

She said both lines on the LIL are functioning and that there were no power interruptions for customers on island or in Nova Scotia due to the damaged tower peaks.

According to Hydro, the damage is unrelated to an outage on the LIL that took the system out of service on Feb. 9.

A daily supply report submitted by Hydro to the province's Public Utilities Board shows a trip occurred on the Labrador Island-Link around noon on that day, leading to a complete outage on both poles of the transmission system, which carries electricity over two wires.

Transmission was eventually restored, about 10 hours later, and the system was able to operate at a maximum of 345 MW. It returned to its current capacity limit of 450 MW about two days later on Feb. 12.

The LIL has been limited to carrying a maximum of just 450 MW – half of the 900-MW maximum capacity it was designed to carry – since a trip occurred on the sub-sea cables in the Strait of Belle Isle in December. It has never operated above 700 MW, although Hydro has said it hopes to perform high-power testing at the end of the winter.