Linemen on track to repair Juneau powerlines
Published Friday, May 9, 2008
JUNEAU -- The avalanches that thundered out of the coastal range near Juneau last month uprooted old growth forest, mangled transmission towers and ripped out a portion of the high voltage lines that link the Snettisham hydroelectric plant to Alaska's capital city.
Now, with rate payers on the hook for an estimated $18 million in fuel to power back-up diesel generators for three months, the power company is pressed to repair the damage as soon as possible.
"People feel like we're just sitting around out here waiting for the snow to melt, and that's not the case at all," said Alaska Electric Light and Power engineer Scott Willis, who is still hopeful that hydropower will be restored by mid-July.
"There's been a tremendous amount of activity getting things mobilized and prepped and now we are accessing sites, foundations are being uncovered and work is happening on the mountain."
It's a tricky business, however.
The massive slides on April 16 left in their wake a jumble of snow — at least 10 feet deep in places — mud, rock and splintered trees while even more snow hangs menacingly along the steep slopes above.
More than two weeks after the event, as officials including Lt. Gov. Sean Parnell and Mayor Bruce Botelho looked down from a helicopter, the swath of destruction intermittently stretching 1.5 miles along Speel Arm appeared untouched except for some equipment at either end.
Instead much of the work was happening at the plant three miles beyond the avalanche site and nearly 30 miles as the crow flies from Juneau.
Workers have been busy seven days a week assembling replacement towers, getting avalanche safety training, making forays to the site and plotting their course of action.
"We are chomping at the bit to get up there, but the bottom line is it has to be safe for our guys," said construction manager Marvin Pickins, his burly arms tucked into bib rain pants.
Forty years ago, the U.S. Army Corps of Engineers built the Snettisham plant in a spot where the annual 180 inches of precipitation is three times the average at the Juneau airport.
It's good for keeping the lakes filled; not so good for safety from avalanches.
Burrowing into the base of a mountain, the engineers hollowed out a rocky bunker that would be fitting digs for a James Bond villain.
This is where water from two high mountain lakes, cascading down more than mile-long tunnels, powers three generators capable of producing a total 78 megawatts of power — almost enough juice for a city of 30,000 people.
While the thrum of machinery usually reverberates off its craggy rock walls, it's much quieter these days.
Snettisham is still producing electricity but just enough to keep its own lights on while it serves as a staging area for some 20 people either working on repairs or as support.
Earlier this week in a cavernous room at the plant, a couple of men were bolting together tinker-toy like transmission tower arms to replace those chewed apart in the slides.
On the grounds outside lie pre-assembled sections for two complete towers and most of a third — all from spare parts already on hand.
"Each structure has about 800 to 1,000 pieces, so we are taking those pieces and assembling them into the full towers that we need," said AEL&P transmission and distribution engineer Eric Eriksen.
At the crew quarters nearby, avalanche expert Bill Glude was leading a safety briefing with a group of linemen who'd just arrived, contracted by AEL&P from City Electric, Inc. in Anchorage.
All of the linemen get three hours of classroom and two hours of on-site avalanche training, Glude said.
Glude and his crew of two also are dropping thousands of pounds of explosives onto the mountainsides in an effort to bring down the remaining snows without causing more damage. And they're experimenting with sand and carpenter's chalk as melting agents for snow slabs that don't respond to explosives but continue to inch ominously down the sheer rock faces above.
"We're trying to get workers into very limited footprint areas. We'll stabilize above those areas and get them in and out," Glude said.
Their efforts allowed workers on the mountain this week to sever the three conductor lines and tie them off at either end of the damage, thus releasing the tremendous tension in the lines still clinging to towers buried in snow. They've also been able to shovel out some of the tower foundations and so far have found them intact.
Though some residents in Juneau grumble at what they consider to be foolhardiness, the company is restoring the towers and line just where they were. Company officials meeting with avalanche crews and transmission line experts out of Seattle determined early on that it would be the quickest way to restore power and, with diesel priced at $4 a gallon, the most economic.
Beginning this month, rate payers are facing a 450 percent increase in their bills to pay for the fuel.
"This is a $7 million fix," said AEL&P general manager Tim McLeod. "The real cost though is the cost of oil in the meantime. So the time it's down is worth a lot more than it used to be."
Only later will they review other options such as submarine cables, reinforced towers and avalanche diversion structures, balancing the risks with each options' total life cycle costs.
None would be a quick fix, McLeod warned. Each would likely require years of surveys, engineering and review and cost millions of dollars to finance.
Even using explosives for preventative avalanche control carries the risk of causing damage where none might have occurred if left alone, said Glude.
Glude said the Army Corps used the best knowledge and technology available when it built the lines in the 1960s, but even so it left the power company and Juneau residents with a dicey inheritance.
"It was built at the same time that people in Juneau were building houses in the middle of avalanche zones. That was the norm," said Glude. "It would be fully engineered for avalanches today, but you need to judge what's there by the standards of the time it was built."
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