Stabilizing Work Underway on Chilliwack River

By Chris Gadsden, Fraser Valley Salmon Society | Published in September 2003

This week saw the start of work on the Tolmie Slide, one of the major clay slides on the Chilliwack River. The work is being co-ordinated under the direction of a volunteer stewardship group, The Chilliwack River Action Committee (CRAC). The Tolmie Slide, just above Slesse Park, started with a major slump into the river in November of 1995.

The Chilliwack River Action Committee was formed in 1997 after another major slide on January 27,1997 blocked the Chilliwack River just above the Tolmie Slide. CRAC first repaired the Slesse slide by raising the berm and using bioengineering methods 3 years ago. This work was very successful as very little clay now enters the river from this slide.

"We were very pleased with the success we had on the Slesse slide, so we started fund raising to tackle the Tolmie slide," David Lamson, chairman of CRAC, said. "We were first able to raise enough money to have the Engineering drawings and work completed before moving into the construction stage of the project this week," Lamson added. Golder Associates Limited of Abbotsford were the Engineers responsible for the design and construction of the project.

CRAC has three reasons for tackling these slides. One is to prevent the loss of land. Another is to lessen the chance of a major slide that could block the river causing damage to residents below the slide. The third reason is to prevent and lessen siltation of the river. "Siltation from these slides smothers downstream river habitat with a coating of clay, sealing spawning gravel, and killing aquatic life" Lamson said. "Many studies have indicated that the single most important factor in maintaining the sustainability of a fishing resource is preserving the quality of its habitat," Lamson related.

The work completed this week saw the construction of 4 groynes placed at the base of the slide. These groynes consist of rip rap, boulders, and large stumps lashed together with cable to prevent them from being dislodged during high river flows. The idea of these groynes, according to Lamson, is to move the water up and away like a wave action that helps keep the water away from the toe of the slide so the erosion pressure is away from the base of the slide preventing further slumps.

Lamson credited many cash donations and in kind donations from The Pacific Salmon Foundations, Fisheries Ocean Canada, Chilliwack River Valley Ratepayers, Fraser Valley Regional District, Ministry of Transportation of Highways, Chilliwack Fish and Game Protective Association, Tolson Logging Company, and Richard Tolmie for the ability to start this work.

During year two of the project in 2004, CRAC hopes to see the project completed with the construction of six more groynes if the needed funds are raised. The first fundraiser is the second annual Spring Salmon Derby to be held over the Thanksgiving weekend. Top prize is $1,000 for the heaviest spring salmon.