Stabilization of Highway Cut Slope Trials using Compost and Straw Wattle Applications

MOYIE BLUFF PROJECT 2

Location: Cranbrook / Moyie, British Columbia

Client: Dawson Construction Limited

Objective: To help stabilize highway cut slope by holding the weathered, compacted glacial till on the slope. To experiment with a combination of straw wattle and compost application on two sites and establish vegetation on extremely steep slopes in order to reduce surface erosion

The Moyie Bluff trial sites are located on highway 95 near the town of Cranbrook in southeast British Columbia. These sites were part of a major highway widening construction project. This various treatment on both sites included: straw wattles, brush layers, live staking, planting of native seedlings, compost application and hydro seeding.

These techniques will help stabilize the slope by holding the weathered, compacted glacial till on the slope. This will address surface erosion, therefore reducing rilling and gullying by establishing a woody shrub component, and grasses and legumes growing on the retained weathered materials. The installed structures are designed to reduce the formation of rill erosion to accelerate re-vegetation of the site and provide slope surface stability. The species component used was 80% black cottonwood (Populus balsamifera ssp.trichocarpa) and 20% willow (Salix scouleriana), harvested locally.