Bridge Approach Stabilization
using Vegetated Crib Wall Techniques
INONOAKLIN RIVER PROJECT
Location: Edgewood, British Columbia
Client: Ministry of Transportation and Highways
Objective: The objectives were to prevent further
undermining of the road prism caused by increased river
erosion, and to protect the bridge infrastructure while
enhancing and creating fish habitat.
The Inonoaklin River project is located upstream
from the town of Edgewood in southern British Columbia.
This project was implemented for the Ministry of Transportation
and Highways. It involved the implementation of a vegetated
crib wall at a bridge approach on the Inonoaklin River.
The structure is composed of a combination of rootwad
revetment and a live crib wall. In addition, the structures
are intended to provide slope stability and increase
fish habitat. The structure design and criteria were
implemented to withstand a 1 in 100-year flood event.
Gerry Oliver of G.G. and Associates Environmental Science
produced the design and implemented the structure. Terra
Erosion Control Ltd. assisted with the construction,
and provided and installed the live cuttings and vegetative
treatment. The live material utilized on this project
was "non dormant", harvested in the late summer,
soaked for a period of ten days, and planted within
the vadose zone. The species used were willow (Salix
scouleriana), and red osier dogwood, (Cornus sericea).
The site was monitored the following fall and during
the summer of 2002 and 2003. Survival results were found
to be excellent.