Transportation Award of Excellence
Highway 1 Keith Road / Mt. Seymour Parkway Interchange McElhanney
An alternative solution MoTI’s greatest need was to complete the project within a constrained timeline to meet the funding requirements of three levels of government. During conceptual design of the Lower Lynn Improvement Program, the project came up against strong public and political pressure, as some partners felt $150 million in funding did not go far enough to resolve congestion. Instead, they believed an eight-lane collector-distributor arrangement was needed, estimated to cost more than $265 million. 38
CANADIAN CONSULTING ENGINEER
McElhanney assessed an alternative solution to meet stakeholder needs while maintaining the schedule and reducing the cost. Within three months, the firm developed a $198-million plan that was unanimously approved by all stakeholders, funding partners and local First Nations, saving the provincial government $67 million while maintaining the program schedule. Key strategies McElhanney’s key strategy was shortening the design schedule from 15 to six months. The time saved provided an additional construction season to ensure the project was completed by its deadline. To accomplish this, McElhanney had three bridge and three highway design teams work simultaneously, in parallel and integrated with geotechnical, drainage, hydrotechnical, utilities, active transporta-
tion and multi-use path teams. Environmental specialists secured regulatory permits within four months, enabling MoTI to release an advance works package to install bridge piles and riprap in Lynn Creek during the in-stream fisheries work window, one year ahead of its own expectations. All four bridge sites along Highway 1 had liquefiable soils in areas of high seismicity. Pile foundations with consideration of liquefaction and lateral deformation were required for the Lynn Creek bridges. Geotechnical and structural engineers collaborated to incorporate springs in the overall structural model to simulate and estimate the lateral behaviour of the bridge and piles under seismic hazards. In addition, cast-in-place parapets on the Lynn Creek structure retrofit added 30 years to its service life and allowed for simplified traffic detouring during construction. September/October 2022
PHOTO COU RT E SY MC E L H A N N EY
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he Highway 1 Keith Road/ Mt. Seymour Parkway Interchange Project and Lynn Connectivity Creek Improvement Program has addressed congestion, road safety and connectivity for Vancouver’s North Shore communities. At $98 million, it is one of the largest and most complex design-bidbuild projects British Columbia’s Ministry of Transportation and Infrastructure (MoTI) has ever undertaken. Part of the larger $198 million Lower Lynn Improvement Program, the project was developed to reduce public frustration over one of the province’s busiest sections of highway. McElhanney had to overcome the challenge of working within a suburban, constrained corridor, including fish-bearing habitat, parks, residences and commercial properties. The firm delivered the project for MoTI through innovative design and scheduling strategies and added environmental and active transportation benefits.
