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 preliminarywork" has been completed to secure the damaged towersbut the bulk ofrepairs hadn't begun because dozens of kilometres of isolated access roads needs 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 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.

First repairs will begin Thursday

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

But Hydro said Thursday the work is expected to take "two weeks, subject to having weather conditions."

Enough plowing has been done to begin the first repairs Thursday, according to the Crown corporation.

"Some of the repairs require working from cranes at a height of 52 metres (170 feet), so inclement weather, high winds and extreme cold especially, would create unsafe conditions," Pitcher said Thursday.

No one at Hydro was available for an interview. Pitcher did not provide a cost for completing the workbut said both lines on the LIL are functioning and there were no power interruptions for customers on the 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 that day, leading to a complete outage on both poles of the transmission system, which carrieselectricity over two wires.

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

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

LIL performing 'above national average,' says Hydro

Pitcher said the damage was reported on just eightof the 3,223 towers on the 1,100-kilometre LIL system, which links the 824-megawatt Muskrat Falls generating station in Labrador to the St. John's area.

"Despite the season's winter weather (cold snaps, icing, snowfall and high winds), our newest transmission line continues to reliably deliver electricity to the island from the Muskrat Falls generating station, which is performing above the national average," Pitcher said.

Last fall, Hydro announced $28 million over four years to reinforce the LIL system, which has seen repeated equipment failures since operations began. Repairs in isolated locations have often proven difficult, with weeks of snow clearing needed before repairs can even begin.

The Muskrat Falls project's final price tag was pegged at $13.5 billion last June, about double what was promised when the provincial government sanctioned the project in 2012.

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