Job for loggers

Engineers working on a project at Shasta Dam early this year had a problem.

A hundred feet above the dam’s powerhouse, where the turbines that generate electricity are located, stretched a 1,700-foot, 3-inch steel cable that was last used in 1952 for a trolley system to place 30-ton concrete blocks at the foot of the dam to stop erosion.

The cable weighed 52 1/2 pounds per foot and officials were afraid it might be weakening and would break and slice through the powerhouse or the five pinstocks, large pipes that channel water down the face of the dam and into the generator turbines. The Bureau of Reclamation, the federal agency that constructed the 603-foot dam in the early 1940s, wanted to take the 45-ton cable down.

Engineers working on the project were stymied by one challenge: How to get the monster cable down safely without hitting anything. Then someone suggested Sweet Home logger Jim Cota.

Cota said his connection with the project came through Ron Richey, owner of Stayton Demolition, a subcontractor on the cable removal project, which was led by Glen/Mar Construction of Clackamas.

Cota said engineers had worked on the project for two years, running up a $300,000 bill, before he got involved.

“They couldn’t come up with a system to deal with the force they were dealing with,” Cota said. “There were 86,000 pounds of pressure on the skyline, on what we had to get hold of and let down.

“Somebody had told Ron Richey, after all the engineers got done with the calculations, that loggers deal with these kinds of pressures every day. Somehow my name got mentioned.”

Cota said he first got involved in the project in February, hauling a yarder €“ a tower-based winch system used to move logs up and down slopes €“ on a Low Boy trailer to the lake.

He said before the job actually got started he had to come up with a plan to get the cable safely to the ground.

“When I become involved, they didn’t have viable plan,” he said. “I ended up writing up the plan. They’re bridge engineers.

That’s why they brought me into this. I’d been to five different meetings. Finally, one of the engineers called me and told me to write the plan.”

Cota said he came up with a strategy to get the cable down and the engineers plugged in the numbers to make it stand up to scrutiny.

Though he was involved with the project for three months, Cota said it actually took only 15 days to do the work.

The cable was anchored to two towers, the larger one 160 feet tall. The cable, which was woven together from individual steel strands like a suspension bridge cable, was surrounded by an interlocking skin that kept water out. Except, no one knew how well the skin had worked.

As it turned out, Cota said, as they lowered the cable and cut it into 40-foot chunks, they found it had worked perfectly.

“We never found a spot where it was rusted,” he said.

Other cables used in the trolley system, for guy lines and other functions, though, had rusted nearly all the way through, he said.

Cota took along two members of his Timber Harvesting crew and had help from a few Stayton Demolition team members. He said the work was complicated by the fact that the towers and other equipment were covered with old lead paint, which required safety precautions and inspections.

“We were held up for different things,” he said.

Andy Brown, director of operations for Glen/Mar, said that the job was a challenge, particularly since the contractors had to deal with protected ospreys who nest in the two towers that supported the cable.

“We had a small window of opportunity to get it down before the birds nested again,” he said. “The biggest problems were shutdowns because of government protocols.”

When the actual work began in April, his team rigged everything, installed new guy lines to the support towers because of the rotten wires, and “had to do a lot of preventative stuff,” he said.

Other safety precautions involved working on the 160-foot front tower, which required the use of scaffolding.

“That was the biggest safety issue, where you were working at, because of the height,” Cota said. “Only four of us were comfortable working at that height.

“But it was a tremendous view.”

Since the cable was directly above the powerhouse and pinstocks, Cota’s team built saddles onto which they lowered the cable. The saddles sat on the powerhouse roof, on the seawall along the dam spillway, and on one of the pinstocks, to protect them from damage by the heavy weight.

When they were ready to go, the team used the two 25-ton chain hoists to pull the cable tight, then give it some slack and cut it between the chain hoists with a power cutoff saw. Then they lowered it with the 70-foot yarder.

“We set everything up on a Thursday,” Cota said. “All the top people from the Bureau of Reclamation and several engineering outfits came out on Monday and said everything looked good. They wanted a day to go through to take pictures of everything that we’d done. Then we cut the first section, lowered it down, and 90 percent of them left.”

He said it took three days to cut the cable and let it down onto the powerhouse roof. Once on the roof, it was cut into 6-foot sections and carried off by hand, he said. Sections of cable that were lowered into the river were removed with an excavator.

Brown, of Glen/Mar, said Cota’s role in safely removing the cable was “significant.”

“He certainly understood the forces and methodology of bringing that thing down,” Brown said. “It was pretty evident the Bureau of Reclamation people were pretty nervous. They didn’t know how this would work.

“When I went to the site and watched the takedown, it went exactly according to plan. It was rather uneventful. It went smoothly, in a very controlled manner. They were able to lay that cable right where we wanted it.”

Brown said he had never worked with logging outfits before but, as project manager, it was “a treat working with Cota and his guys.”

“They did a fantastic job. We would never have made the connection between logging and what we were doing there, but without a doubt, it was the right equipment. the right guys, the right company.”

Cota said the Shasta job has led to other opportunities, including a logging job at the new Coast Community College site in Newport and a recent trip down to the Shasta area again to look over a dam the Bureau of Reclamation wants to remove, which also involves a lot of lead paint, he said.

“It was something different. It was fun,” Cota said of the Shasta experience. “The guys who worked on the job did real well, made real good money. It was a good boost for them.”

“The way things are today, if you can do something like that you can keep some guys working because the logging end of things is slow.”

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