New Wetlands May Grow From Old Logs

Jun 10, 2015

It may sound odd to think of restoring a vital wetlands on Lake Pend Oreille by throwing old logs, tree limbs and dirt into it. But that's what government agencies and volunteers are doing in the rapidly disappearing Clark Fork River delta.

The regional supervisor of the Idaho Department of Fish and Game calls the work "restoring ecological function in the delta by using environmentally compatible stabilization methods."

But behind the formal language is a lot of hard grunt work - hauling in logs, vegetative litter, detritus and soil to replace what's been lost over the years by two big power dams - one above the Clark Fork inlet to Lake Pend Oreille, and one below it.

Restorers have also planted about 100-thousand native shrubs and trees - cottonwoods, dogwoods and willow - in part of the rich three-by-four mile delta, and they're ripping out invasive reed canary grass.

It's a multi=million dollar project, paid for by Avista, which owns one of the dams, the Bonneville Power Administration, the US Army Corps of Engineers, the Kalispel tribe, Ducks Unlimited and other groups.

Since the Cabinet Gorge Dam on the river above the lake was built, sharp fluctuations in the lake level have let  river banks in the delta sluff away, amounting to about 15 acres a year taken by erosion.

The old logs and vegetation are meant to help anchor the soil in the meandering river banks.