Depth of winter drawdown still unclear
SANDPOINT - The depth of the annual winter drawdown of Lake Pend Oreille remains up in the air.
The U.S. Army Corps of Engineers announced last month a plan for the early stages of the drawdown, but the ultimate depth won't be known until after the annual inter-agency meeting on Sept. 27.
That's when tribal, state and federal fisheries managers and other resource officials gather to consider the factors that influence a recommendation to lower the lake to 2,055 feet above sea level or 2,051 feet.
The panel considers the winter pool elevation in previous winters, the needs of chum salmon below the Bonneville Dam, the needs of Pend Oreille bull trout and kokanee, and the long-range weather forecast. The considerations shape a recommendation to the Columbia River Basin technical management team.
The limited number of spawning kokanee in the last two years has helped influence a deeper winter drawdown, but Idaho Department of Fish and Game's Panhandle region supervisor, Chip Corsi, said the number of kokanee spawners this year looks more promising.
"It's too early to really tell what we've got. I think the (fisheries) guys have been encouraged by some of what they've seen, but we have to do our trawling yet," Corsi said.
Trawling to gauge the spawning population is planned for next week. If the population reaches a threshold of 70,000, it could help trigger a recommendation for a higher winter pool to maximize the amount of spawning habitat.
"If we see a continued increase in kokanee numbers, then the likelihood is that we're going to push pretty hard to have the lake held up," said Corsi.
The corps' initial lake-drafting plan, meanwhile, is drawing opposition from the Pend Oreille Basin Commission.
The plan involves raising the lake to 2,062.4 feet, then dropping it to 2,061.6 feet and then refilling it to 2,062 feet so that the typical drawdown of 1 foot could commence on Sept. 15.
"This seems to be a technique to fluctuate the lake below the standard summer pool before the characteristic drawdown is to begin. The Commission has concerns that this is setting an unacceptable precedent of drafting water from Lake Pend Oreille for any downstream procedure that arises, without any consultation," commission Chairman Ford Elsaesser said in a letter to the corps.
The commission points out that the lake existed prior to the Albeni Falls Dam and contends that fluctuations must be kept at a minimum in order to keep the lake system healthy. Moreover, waterfront landowners and boaters have come to depend on standard lake levels for recreation.
"The lack of advanced notice for this atypical lake fluctuation is of the utmost concern," Elsaesser said in the letter.
The commission is also concerned the changing lake level will hasten erosion in the Pack River and Clark Fork deltas, in addition to skewing baseline data that is being collected in connection with a Bonneville Power Administration proposal to fluctuate the winter pool elevation to maximize power generation in the Columbia Basin.
The commission is asking the corps to reconsider the initial drawdown plans and return to the standard release schedule.