PROJECT SUMMARY
Client: BC Ministry of Transportation and Infrastructure
Location: Westwold, British Columbia
Summary: Ecora’s Geo-Hydro Engineering Group was contracted by the BC Ministry of Transportation and Infrastructure (MoTI) to carry out a geotechnical assessment and detailed geotechnical and hydrotechnical design for the rehabilitation of Campbell Bridge, located on the Salmon River approximately 21.5 km south of Westwold, BC along the Douglas Lake Forest Service Road.
THE CHALLENGE
The foundations of the right abutment of Campbell bridge was undermined during the spring floods in 2017, and were temporarily stabilized using rip rap during the flood event. Ecora was retained to develop a solution to stabilize the existing bridge foundations without closing the road to traffic, within the short timeframe for which in stream works were permitted. Access to the underside of the bridge was limited due to height of the bridge deck, and the river had to be diverted around the work site using several large pumps.
THE SOLUTION
Ecora’s Geotechnical & Hydrotechnical engineers provided a solution to stabilize the existing bridge using soil nail underpinning and armouring of the riverbanks with rip rap. This solution increased the hydraulic capacity of the stream channel under the bridge, improved the channel alignment and provided protection from scour damage that could result from future flood events. Our engineers were on site during the installation of soil nails, and were able to provide field modifications to the design where limited machine access under the bridge made installation difficult.
THE RESULTS
Ecora’s flexible design, and our ability to make changes on site allowed the contractors to complete the rehabilitation works within the tight schedule, and to the satisfaction of the MoTI.
