For the week of August 14 - 20, 2002

Projects rehabilitate south county streams

Work on tributaries protects Silver Creek

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By GREG MOORE
Express Staff Writer

The Blaine County Commissioners on Monday approved stream alteration permits to rehabilitate two tributaries of Silver Creek this fall.

BEFORE: This photo taken in August 2000 shows a segment of Chaney Creek, south of Gannett, after decades of cattle grazing had made it wide and shallow. Photo courtesy Sawtooth Environmental Consulting

The projects are part of a wider effort begun two years ago to reverse the damage caused to the Silver Creek drainage by a century of unrestricted cattle grazing.

"It’s part of a change in land-use philosophy throughout the country," said Trent Stumpf, owner of Sawtooth Environmental Consulting, which has been directing the effort with another local consulting firm, Conservation Inc.

AFTER: By October 2000, structures had been built to narrow and deepen the stream and to create meanders. And by August 2001, vegetation was growing on the filled areas and the stream was returning to something similar to its pre-grazed condition. Photo courtesy Sawtooth Environmental Consulting

Attempts to halt degradation to the well-known trout fishery began in 1980 when the owner of property upstream from The Nature Conservancy’s Silver Creek Preserve agreed to erect a fence to keep his cattle out of the creek. Once the stream banks were no longer being trampled, riparian vegetation reappeared quickly.

"The change in 12 months was incredible," said Guy Bonnivier, owner of Conservation Inc.

But merely removing the cause of the destruction was not enough to bring other, more degraded stream segments back to health. Being spring-fed, the Silver Creek system lacks the annual floods that sweep away silt and bring new gravel to the beds of most other creeks. An extra boost was needed.

In 2000, Stumpf and Bonnivier undertook a project on Silver Creek Ranch, south of Gannett, to reconfigure about four-fifths of a mile of Chaney Creek. Their intent was to narrow and deepen the stream, clean its gravel bed and enhance riparian vegetation.

Using 12-inch diameter Biologs made of coconut palm pulp, they built meanders that reduced the creek’s width from about 100 feet to about 30 feet. Excavations in the creek created deep pools on the bends and shallow riffles on the straight sections. The dredged material was used to fill in behind the logs, creating places for willows and other riparian vegetation to grow. The pulp logs are designed to allow the plants’ roots to penetrate through them and reach the soil below, and disintegrate after five years.

A similar project was carried out on nearby Wilson Creek.

"So far, we’ve had a lot of success with this approach," Bonnivier told the commissioners Monday. "The fisheries response has been pretty immediate."

He said 23 rainbow trout redds were recently counted on the segment of Chaney Creek.

The newly approved projects will be on Grove Creek, which is also on Silver Creek Ranch, and on Rio Creek, between Gannett and Picabo. They will cover more than a mile of Grove Creek and about one-quarter mile of Rio Creek.

"Grove Creek is a standard degraded stream," Stumpf told the commissioners.

Stumpf said the projects will take no more than a few weeks to complete and will be done by the end of September.

The cost of such projects, Bonnivier said in an interview, is $25 to $30 per linear foot. Though that can add up to a hefty chunk of money, much of it can be borne by the federal government. Under the 2002 farm bill, the government will pay up to 75 percent of the cost of conservation projects on agricultural land. That will even be increased to 90 percent for those who can plead poverty. Applications are evaluated on the basis of cost efficiency and ability to meet national conservation priorities.

Bonnivier said that for his next project, he’s looking at rehabilitating about 10 miles of Camas Creek, west of Magic Reservoir, that’s been channelized. And he said that’s only one of many potential riparian conservation projects in Blaine County.

"There’s a lifetime of work out there," he said.

 

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