The Trans Canada Highway Underpass Bridge consists of separate northbound and southbound structures and retaining walls similar to the Barnston Drive Underpass structure. The major challenge to the design of the Barnston and TCH bridges was the limited width of the Right of Way for construction of the new highway, and the resulting need for retaining walls to be constructed immediately on the R.O.W. This required the use of a propped retaining wall design. Struts spanning between the east and west retaining walls provided support for the walls, which themselves consisted 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. The bridge uses 50m maximum spans, with eight southbound and nine northbound spans. Each structure consists of pre-stressed 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.