The Walter SNC Joint Venture retained Ausenco Sandwell to design the new Middle Arm Bridge to the Vancouver Airport. The new three-lane bridge carries the westbound traffic and a sidewalk and parallels the existing bridge, known as the Moray Channel Bridge, which carries two eastbound lanes. The old bridge is a low-level structure with swing spans over the navigation channels to accommodate vessel traffic. The new bridge is a high level fixed structure with 10 m clearance over the navigation channel to accommodate vessel traffic.

Ausenco Sandwell designed an eleven span continuous structure with prestressed concrete girders built into caps on extended steel pipe piles. The deck slab consists of first stage precast panels, cast-inplace second stage composite slab, membrane and asphalt surface. The soils at the site are of a dense sandy layer with soft soils above and below. An innovative pile tip was developed to minimise the required pile diameter while maximising the bearing and shear capacity of the pile in the sandy layer. The piles were battered to minimise predicted settlements due to consolidation of the weak silty soils. The piers are protected from vessel collision by innovative yielding fender piles and floating fender frames that absorb the vessel collision energy without imparting excessive loads of the piers.

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