CLIENT: British Columbia Ministry of Transportation and Infrastructure
LOCATION: South Taylor Hill, British Columbia, Canada
BGC was retained by the British Columbia Ministry of Transportation and Infrastructure (MOTI) to provide geotechnical designs to improve a 1.4 km section of the Alaska Highway 97 at South Taylor Hill; on the southern approach slopes of the Peace River about 20 km south of Fort St. John, BC.
The project improves the highway by widening from the existing two-lane geometry to a four-lane geometry. This project has been particularly challenging since Highway 97 traverses a large landslide complex through (and beyond) the project limits, with slope movements affecting this segment of the highway since the highway was built by the US Army in the early 1940s.
BGC developed a detailed geological and hydrogeological model of the hillside that facilitated detailed stability analyses of complex geological sections from which designs were developed to stabilize slopes with slip surfaces at multiple levels.
A staged approach to construction was recommended with daily monitoring of geotechnical instruments for possible reactivation or acceleration of slope movements and changes in pore water pressures.
BGC won the BC MOTI Deputy Minister’s Awards in the Specialized Engineering Services category in 2015 for its design, construction supervision and overall contribution to this project. BGC is currently providing similar geotechnical design services to the MOTI to improve the remaining 2.5 km section of South Taylor Hill.