Berms Planned For River Controversial Project Expected To Slow Erosion Of Contaminated Cda Riverbanks

Promising to protect water, vegetation and public access, engineers on Wednesday explained a proposal to slow erosion of metals-contaminated riverbanks along the lower Coeur d’Alene River.

Some regulatory hurdles remain before workers begin building rock berms in the river. The work is experimental, controversial and affects only a small part of the river.

But if all goes as planned, the three-year project will begin this winter.

“This will stabilize the bank in a very natural way,” said engineer Frank Shuri.

Shuri spoke at a public hearing held by the Idaho Department of Lands. His firm, Golder Associates, is working for the Silver Valley Natural Resource Trustees. That organization is planning the project on behalf of the Coeur d’Alene River Commission appointed by Idaho’s governor.

Boat wakes and spring runoff both cause the shoreline to crumble. Lead, zinc, cadmium and other toxic metals from historic mining practices go into the water along with the dirt, washing toward Lake Coeur d’Alene and the Spokane River.

The lower river is 30 miles long. The project would take place in the five miles between the boat ramp near the Cataldo Mission and the bridge at Rose Lake.

A survey in that stretch identified 15,600 feet of shoreline with severe erosion. Another 23,700 feet have moderate erosion.

“There’s not enough money to do all the riverbank, so we’ve proposed to start with the most severe areas first,” said project coordinator Marti Calabretta.

The trustees are eager for people to know that the project does not involve putting big rocks on the riverbank.

Instead, small berms made of 8-inch rocks would be built some 10 to 15 feet from shore. The piles of rock would stick up 2 feet above the summertime level of the river.

The areas between the berms and shore would have ankle-deep water, Shuri said. Eventually, they would become wetlands as dirt falls into them and plants start to grow.

The rocks would be barged in, to avoid disturbing the shoreline with heavy equipment. No new quarries would be dug to acquire the rock, Calabretta said.

Work would be done when the water is low, between November and January.

The berms would be individually designed as the work takes place, Shuri said. The engineering team would include state wildlife and environmental scientists.

Popular parts of the shoreline would remain accessible to boaters “as much as possible,” according to the plan.

Shuri predicted that 6,000 feet of berms, or more than a mile, could be completed this winter. “We’ll go until we run out of rock, which means we’ve run out of money.”

After engineering fees are paid, about $243,000 will be available to spend on the project this year, according to trustee chairman Chuck Moss. Half the money would come from the Idaho Division of Environmental Quality. The other half, from the mining industry.

It would cost $3 million to $4 million to build enough berms to protect all of the shoreline in that five miles, Shuri estimated.

This would be the first major project to deal with metals contamination on the Lower Coeur d’Alene. That’s a subject of great controversy because of its cost and the potential for disturbing wildlife and vegetation.

The Coeur d’Alene Tribe, which is in court fighting for control of the riverbanks, is wary of the state project. Staff biologist Phil Cernera called it premature, in part because ongoing studies may conclude that the contaminated soil needs to be removed from the riverbanks. He also fears the rocks will just wash into the channel.

“It’s good that people are trying to demonstrate what works and doesn’t work” to limit contamination, Cernera said. “But I think the state wants to just dive into this thing to perpetuate the impression that ‘We’re the only ones doing anything, everyone else is litigating.”’

The tribe will send its criticisms to the U.S. Army Corps of Engineers. The corps must issue a permit for the project and could potentially require a full-blown environmental review.

The Environmental Protection Agency and U.S. Fish and Wildlife Service, which have been doing their own studies of the river, are expected to comment, too.

“We have concerns and questions regarding some of the project features,” said Rick Donaldson of Fish and Wildlife.

Idaho Fish and Game supports the project, although its biologists cautioned against doing work that would disturb wildlife, such as nesting eagles.

Friday is the official deadline for public input to the Corps of Engineers. But staffer Mike Doherty said he will accept comment up until the time he decides whether to issue a permit, which should be within the next few weeks. Comments can be sent to the corps at 3815 Schreiber Way, Coeur d’Alene, ID 83815-8363.

The state Department of Lands must also issue a permit for the project. Its comment deadline ended Wednesday.

This sidebar appeared with the story: Comments Comments can be sent to the Corps of Engineers at 3815 Schreiber Way, Coeur d’Alene, ID 83815-8363.