Construction crews this week began repairs on a leak in Newport Avenue Dam. While the leak is similar to those that have developed in the dam’s wooden paneling in years past, Tom Gauntt, spokesman for Pacific Power, the utility that operates the dam, said this should be the last repair project of this kind needed to stop leaks in the 108-year-old dam.

Newport Avenue Dam, built in 1910 to stem the flow of the Deschutes River, generate electricity and create Mirror Pond near Downtown Bend, sprung leaks in wooden paneling over a defunct outlet on the dam in 2008, 2009 and 2014.

The dam’s most recent leak occurred in mid-October, when a small leak caused water levels in Mirror Pond to drop by more than 2 feet, exposing berms and other areas of the pond that are usually submerged.

As with other leaks in the paneling, the crews plan to use sheet pile — long, interlocking pieces of steel that form a shield-like structure — to keep water from reaching the leak, according to Gauntt.

Pacific Power has covered other portions of the dam with the metal structure, though Gauntt said this is the last time the utility will need to use the technique.

“This is the last section of the dam that hasn’t had that installed,” Gauntt said.

Construction crews assembled a 300-ton crane near the edge of the dam, which will be used to install the sheet pile on the mouth of the dam.

Pacific Power declined to disclose the cost of the project.

Gauntt said the utility will need to lower water levels by 3 feet during construction, although he said he didn’t expect there to be any impact on fish living in the pond. He added that he expects construction to continue into next week.

“It should be done by Thanksgiving,” Gauntt said.

— Reporter: 541-617-7818, shamway@bendbulletin.com

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