Grauer Road Dike
The Vancouver Airport Authority retained Kerr Wood Leidal (KWL) to relocate a dike on Sea Island to accommodate the development of the McArthurGlen Designer Outlet Centre Vancouver Airport mall, a major retail development. Location options for the new dike alignment were limited because of private land, development plans, and existing infrastructure constraints. The Airport Authority’s preferred relocation alignment was at the south approach of the Arthur Laing Bridge, which connects Sea Island to Vancouver. KWL led a multidisciplinary team of engineers that developed an alignment that raised Grauer Road so that it would become the dike and would curve under the bridge through a set of bridge piers.
The team developed a unique, lightweight dike design, inspired from road designs on poor soils. The team, however, had to find a way to make the materials not only lightweight but also impermeable so as to meet flood protection requirements. The unique design involves a steel sheet-pile wall buried inside a lightweight road fill of pumice, topped with road materials and asphalt paving. Because of concerns regarding the structural response of the bridge under seismic conditions should the road be built against the piers, dike fill was kept back from the piers using lock block walls.
The project was tendered in April 2014 and completed in fall 2014, ahead of the July 2015 mall opening. KWL completed the conceptual design, detailed design, and provided construction services.