Anglers aim to keep lake ice open - Lake impacted by elimination of groundwater seepage due to irrigation pipe enclosure

By John Hanron, Methow Valley News

12/25/02

The Methow Fly Fishers are trying an inventive technique to minimize possible winter fish kills at a couple of area lakes.

The group has constructed and placed three heat-absorbing tubes in both Campbell Lake and Big Twin Lake. The tubes are made from 12-inch diameter pipes placed vertically and attached to black rubber inner tubes and a small wooden frame.

"The idea is that the black tubes will absorb the heat and melt the surrounding ice," said Ben Dennis, president of the fly fishers group.

Water levels have been lower than average in most area lakes after two years of drought. The level in Twin Lakes has been further impacted by the elimination of groundwater seepage from the Wolf Creek ditch, which was enclosed in a pipe this year.

Dennis said the lower lake levels means there is less oxygen storage for the trout that overwinter there. When ice and snow seal off the surface and block the sunlight, underwater plants stop producing oxygen and start using it up during decomposition.

"The less water you’ve got the more problem you’ve got," Dennis said.

Although fish are typically dormant in the winter and do not need much oxygen, Dennis points out that shallow water increases the danger of a large winter fish kill.

Holes in the ice, maintained by the floating ducts, will allow toxic gases like methane to escape and will allow oxygen to enter the water.

"If it works," said Dennis, "we can expect bigger, better trout fishing in these waters."

He added that holes drilled by ice fishermen help add oxygen to the waters as well.

Joe Foster, regional fish program manager for the state Department of Fish and Wildlife, said he was unfamiliar with the units the fly fishers club has placed in the lakes, but thinks they are a good idea if they work.

"If those things work to open up fairly large expansive area, it could be good." he said.

The agency usually brings in compressors and hoses to aerate lakes that it is concerned about.

According to Foster, the lakes don’t have a naturally sustaining population of trout, but depend on stocking annually to augment the perennial population.

"Those Twin Lakes are pretty important to the Methow area," Foster said. "They bring in a lot of people."

He said he was thankful for the proactive local fishermen who are trying to safeguard the fisheries in the local lakes and rivers.

"I’m glad we’ve got them."