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Contractor: threat to water line seen in dam proposal

Pipeline under high pressure

The city of White Salmon needs to watch out for what happens to its main water pipeline if Condit Dam is removed, warns one of the men who was involved in putting the pipeline in place in 1957.

Don Gibbons, now 75, was just a young buck when he worked on installing the steel water pipeline that now delivers water to White Salmon's water customers.

"I installed the pipeline 50 years ago this year. I was 25 when I got that job," said Gibbons, who now lives in Vancouver. "I put a lot of work into that pipe, and I'd like to see it taken care of -- and not see White Salmon be out of water. That could certainly happen, and they'd be in real trouble."

The concern is, the lake would be drained if Condit Dam is removed -- and that could cause big problems for the pipeline.

"When they take the dam out, the silt will wash away and expose that pipe. The pipe is under incredible pressure -- 320 pounds per square inch," Gibbons pointed out. "At that pressure, that pipe will cut steel like a butter knife. At that pressure, that pipe would go crazy."

Gibbons grew up in White Salmon, and by the age of 25 owned his own company, Don Gibbons Construction. The company was hired to install the steel pipeline that carried water to the city from Buck Creek to the city's Spring Street Reservoir.

"It starts several miles up Buck Creek, where there is a coffer dam, and it runs downhill to the reservoir," Gibbons explained.

According to Gibbons, the water line was built with 14-inch diameter steel pipe that is 3/16 of an inch thick. The pipeline is nearly eight miles long, and a portion of it runs under Northwestern Lake.

"We buried it in silt at the bottom of the lake. We had divers and we poured concrete on it," Gibbons said.

The Washington Department of Ecology's Final Environmental Impact Statement (FEIS) on Condit Dam removal, issued on March 23, 2007, backs up Gibbons' point of view. The document addresses potential risks to the city's water pipeline under the lake.

In fact, the city's water infrastructure warrants several mentions.

The city's pipeline is identified in the FEIS as follows: "A 14-inch steel water supply line owned by the city of White Salmon crosses the reservoir midway between the dam and the Northwestern Lake Bridge (about one mile north of the dam)," reads an excerpt. "The pipe, buried in lake sediments, provides service from the White Salmon water system (wells and storage reservoir) to homes and other facilities on the west side of the reservoir in Skamania County."

In another section, under "Public Services Impacts," Chapter 4.12.2, it reads: "The city of White Salmon's 14-inch supply line across the reservoir would be affected by dam breaching and removal activities, potentially resulting in a disruption of service to water use customers."

However, in the mitigation measures listed in Chapter 4.12.3, the FEIS recommends a fix: "In coordination with the city of White Salmon, install a temporary water supply (probably 14-inch HDPE pipe) across the lake with a cable support system before the dam is breached. Install a permanent line after the dam is breached, low enough to be protected from river scour."

Mike Wellman, the city of White Salmon's water systems engineer, said he has talked with PacifiCorp's engineers about the effect of dam removal on the city water infrastructure.

"The removal of the dam will expose the pipeline. That will have to be taken care of," Wellman said. "We want to review and approve whatever plan they come up with. There has to be a temporary pipeline, then a final pipeline replacement. We've said it has to meet our approval and the approval of the Washington Department of Health."

Gibbons said it was vital that the FEIS document considers the impacts of dam removal to the water pipeline.

"The Environmental Impact Statement should cover that," Gibbons said. "It's one of the things that could happen if the dam is removed. I think it's important to the city that the pipeline is taken into account when they remove that dam."

Wellman said he has met with the PacifiCorp engineer who is reviewing impacts of dam removal, and the utility is well aware that the pipeline situation has to be resolved before the dam could come out.

"They know they have to do that and they want to do it right," Wellman said. "They don't want to impact our operation at all."

The pipeline was not the only infrastructure issue addressed by the Final Environmental Impact Statement.

In the section of the Department of Ecology's FEIS regarding "Land use/critical areas" (Chapter 4.9), protecting the city's wells is also taken into consideration. The WDOE document specifically mentions White Salmon Well No. 2.

Mitigation measures proposed to avoid harming the well field are described as follows: "Protect city of White Salmon Well No. 2 by not conducting work within the well setback area. Provide protection measures around the disposal site to prevent potential long-term leaching."

"We feel there may be some impact to our wells," Wellman added. "We're concerned about the potential to impact our groundwater table."


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