Ausenco Sandwell worked with Bilfinger Berger on the design of Barnston, TCH and Westcon bridges for the Golden Ears Design Build Project for the GVTA. The bridges provide access to the main Golden Ears Bridge. Barnston Drive Underpass Bridge carries the existing four lane Barnston Road over the new four lane highway. The bridge has a 29m single span with prestressed I-girders and integral abutments founded on bored 900mm diameter reinforced concrete piles. On either side of the bridge the new highway there are in cutting between retaining walls. The Trans Canada Highway Underpass Bridge consists of separate northbound and south - bound structures and retaining walls similar to the Barnston Drive Underpass structures.

The major challenge to the design of the Barnston and TCH bridges were the limited width of the Right of Way for construction of the new highway which resulted in the need for retaining walls to be constructed immediately on the R.O.W. This required the use of a propped retaining wall designs. Struts spanning between the east and west retaining walls prop the walls, which consist of bored concrete piles with shotcrete between the piles and precast concrete facing panels. The Westcon Overpass Bridge is a twin structure crossing Telegraph Trail, CN rail tracks and the Westcon Building. Each two lane structure is 340m long with built-in construction at the piers and maximum spans of 50m, with eight southbound spans and nine northbound spans. Each structure consists of prestressed I-girders on hammerhead piers founded on 2.5m diameter bored monopiles. The major challenge to the design of the structures was the high seismic load demands on the substructures, which resulted in the need for the large diameter monopiles with steel casings and reinforced concrete cores. As the Engineer of Record for the bridges and retaining walls, Ausenco Sandwell was responsible for the design, and ensuring that the structures were constructed in accordance to the designs and specifications.

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