Harbourside Transportation Consultants completed the design of the vertical and horizontal alignments, from initial concept layouts through to detailed design and tender for the new approaches to the Dicks Brook Bridge Replacement.

Alignment options developed conformed to the requirement that the bridge and realigned section of highway is to conform to an RCU 80 cross section. A modified section was developed for use for Gros Morne projects. This standard assembly was used for highway realignment at Baker’s Brook. The revised typical section provides safety and comfort for the roadway.

Two main horizontal alignment/bridge location alternatives were developed. Within each of the two main alternatives, higher design speeds were investigated, including 90 km/hr and 100 km/hr. These higher design speeds resulted in excessive amounts of earthworks (both filling and cutting) to achieve the shallower vertical sag curve profiles required and are not practical. For completeness, vertical profiles for 80 km/hr, 90 km/hr and 100 km/hr were included.

A temporary detour bridge alignment and a permanent bridge alignment to the north of the existing structure were investigated in addition to the two options presented to the south of the existing, however, with the extensive rock cuts that would be required for these options, they were ruled out as being impractical.

A major requirement of the Dick’s Brook Bridge Replacement Project was the need to maintain two lanes of uninterrupted traffic throughout construction. This requirement influenced the alignment options developed, the bridge design options, the global phasing plan and, of course, the overall project budget. The constrained site with close proximity to the rock road cuts North and South of the structure and the skew of Dick’s Brook through the site and the local topography also influenced global phasing plans by mandating that the on-site detour and the new bridge structure be located adjacent to each other so as to limit the overall project footprint and prevent the need for extensive rock cutting.

Each of these requirements/obstacles was handled through careful planning by both Harbourside and PCA throughout design and through the creation of innovative, complete and accurate drawings and technical specifications.