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Power crisis: Southcentral Alaska electric utility rethinks line over avalanche concerns

Suzanna Caldwell

Almost like clockwork for the last three years, Chris Botulinski of the Copper Valley Electric Association has had to send a team of workers into danger to repair electrical transmission lines that keep getting torn down by avalanches.

He doesn’t like it, but it’s the only way to repair the 106-mile, 138-kilovolt transmission line that runs between the Copper River basin and Valdez that was built in the middle of an avalanche zone.

Consequently, the utility is moving forward with plans to move the Thompson Pass transmission line out of danger. Moving the line will mean more efficient electric transmission, lower energy costs for customers and greater safety for workers maintaining the line.

Opposition has come from recreationalists and those wanting to protect the view of Worthington Glacier.

Time is running out, though. Botulinski, the Copper Valley manager of transmission and distribution, has worked with the transmission line since 2002. The avalanches that wipe out transmission line structures happen in three-year increments, he said. Based on historical data, Botulinski expects another incident before the end of the year.

“I'm not a statistician, but the numbers are not in our favor,” he said.

A history of avalanches

The transmission line was built in the early 1980s as part of the Solomon Gulch Hydroelectric Project in Valdez. Solomon Gulch produces about 50 percent of Copper Valley’s total system requirements, although that changes year to year based on need. Currently, the CVEA cooperative has about 3,600 members and provides electricity to an estimated 8,000 people.

When the line was built, there was worry over avalanche danger to the transmission structures. A full report wasn't released until 1981, but by then the owners at the time, the Four Dam Power Pool Agency, decided to go ahead continue and incur damage costs as they came.

Nothing serious happened until 1988, when an avalanche wiped out one of the X-shaped structures, which had a domino effect of pulling down six others. The line was redesigned to withstand a domino effect, but that hasn't stopped avalanches from taking out single structures in three-year increments since 2000.

Copper Valley took over the line in 2009. Part of the settlement includes the agency (now known as the Southeast Alaska Power Agency), paying for the cost of relocating the line.

Since the line was built, more than $2 million has gone toward replacing the structures. That doesn't take into account the cost Copper Valley customers incurred whenever the line was down. When power from the hydro plant in Valdez isn't used, the Glennallen Diesel Plant generates all the energy for the Copper River basin. The extra fuel costs customers several cents more a kilowatt hour, Botulinski said.

A snowballing debate

Two relocation routes have been purposed by Copper Valley to the Department of Natural Resources. Both move the line west of the highway and both pass by the Worthington Glacier -- how closely is still yet to be determined. What’s called Option 2A would offer a “far perspective,” but creates obstacles for winter recreation in the area. Option 7B uses less obtrusive, single-pole structures, but its placement would be more obvious.

The cost varies between $2.1 and $2.8 million.

During the public comment period in May, about 70 people submitted opinions to the state Department of Natural Resources.

The project found support from groups like the Alaska Power Association, Ahtna, Inc. and the Valdez Snowmachine Club. But most comments opposed an above-ground line. Many would like to see the line buried.

“I'd rather do the smartest possible thing we can do to keep the beauty of Thompson Pass alive,” said Howard Stoddard, owner of Alaska Backcountry Adventures, which offers heliski trips in Thompson Pass.

Going underground?

However, burying the line comes with its own myriad of problems.

While technology has improved, there is still the chance of an underground line failing. Fixing it means excavation, tricky business given the unpredictable weather of Thompson Pass, which is one of the snowiest places in Alaska, receiving, on average, about 540 inches of snow a year.

The junction points of an underground cable are enclosed in cement vaults,  which are prone to water leaks and freezing. The vaults could be built above ground to prevent water damage, but they're still intrusive to the area. A small above ground vault is 8 feet tall and 20 feet long. Botulinski said nine to 14 of them would have be built.

It also takes a lot of power to re-energize an underground line. Currently, the small Copper Valley system wouldn't have enough energy, should the line fail. Another substation would have to be built or facilities would have to be upgraded.

The cost of an underground line is much more -- between $8-10 million in total -- than the above-ground line.

While many distribution lines are buried, most transmission lines are not.

Karsten Rodvik, spokesman for the Alaska Energy Authority, said buried transmission lines are expensive and impractical to operate.

Chugach Electric, which operates in Anchorage and the northern Kenai Peninsula has 539 miles of transmission line. Of that, less than a mile is buried, according to Phil Steyer, director of government relations and corporate communications for Chugach. The small portion of line buried is only because it bypassed the end of a runway at Ted Stevens International Airport.

Even that small portion has caused problems. Several years ago, construction workers accidentally dug into it. Chugach spent six weeks trying to fix it. The utility had to bring in a specialized crew from Italy. In total, it spent about a quarter of a million dollars repairing the line.

“You put your system at risk with (buried transmission lines) and that's why Chugach is resistant,” Steyer said.

Safety concerns

The earliest Copper Valley could begin work on the project is September. Natural Resources still has to approve the land permits, and the Federal Aviation Administration will offer input, since the line runs beside a rural airstrip near Worthington Glacier.

But Botulinski's greatest concern is for his crew when the current line goes down. Each time a structure is hit, he has to send four to seven men out into an avalanche zone to reconstruct it. While Copper Valley takes serious precautions, including having an avalanche expert on site, it still puts workers in a fresh avalanche zone. With weather conditions constantly in flux in Thompson Pass, that's a scary situation.

“I'm in charge of the people who go up there and (avalanches) are always the primary concern,” he said. “What if something bad happens? It spooks me every time.”

Contact Suzanna Caldwell at suzanna(at)alaskadispatch.com

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