Coldwater concept facing scrutiny

PRIEST RIVER — The concept of installing a large exposed pipe at the south end of Priest Lake to cool water in the Priest River is going up in smoke.

“We have heard loud and clear concerns about the aesthetics,” Chip Corsi, Fish & Game Panhandle region director, said during the Idaho Lakes Commission’s meeting on Thursday.

A draft engineering report for the cold-water concept showed a pipe 4 1/2 feet in diameter running down the Outlet Bay corridor, raising the hackles of residents.

Corsi, however, emphasized that engineers at McMillen Jacobs Associates are being sent back to the drawing board.

“We have instructed the engineering firm that that’s not going to be an acceptable approach,” Corsi said.

Fish & Game has been scrutinizing the concept of drawing from the lake’s cool hypolimnetic layer and shunting it to the river in order to improve habitat for native bull trout, westslope cutthroat trout and mountain whitefish. Studies dating back to the 1970s, 1990s and 2000s show an abundance of only mountain whitefish.

“In essence, Priest River is an under-performing coldwater fishery,” said Corsi.

McMillen Jacobs is studying four concepts, three of which involve hypolimnetic withdrawal. A fourth concept examines utilizing groundwater to bring temperatures down in the river.

Corsi said the project would fulfill the department’s 81-year-old charter to protect and enhance fish and wildlife habitat while improving fishing opportunities for anglers.

The state estimates an improved fishery on Priest River could generate up to $1.5 million annually in tourism revenue.

The concept has been embraced by some, but is being met with skepticism.

Some remain unconvinced that water can be pulled from the lake without affecting its level or that temperatures can be meaningfully reduced. In addition to the aesthetic concerns, some are also worried that water in the lake will become stagnant.

“There’s a lot of negative results from coldwater bypasses,” said Peter Bock, referring to failed efforts on California’s Shasta Lake and Oregon’s Detroit Lake.

Corsi said those projects were too dissimilar to the one being contemplated at Priest Lake. However, the project’s potential impact on the limnology of the lake is something that’s going to be closely studied if the concept continues to advance.

“That’s a concern that’s come up. It’s a legitimate concern,” Corsi said.

Corsi also emphasized that the project remains in its infancy.

“We are very early in the process. There has been some misunderstanding about that,” he said.

Keith Kinnaird can be reached by email at kkinnaird@bonnercountydailybee.com and follow him on Twitter @KeithDailyBee.