Cross harbour traffic between Halifax and Dartmouth is handled by two suspension bridges, which are owned and operated by the Halifax-Dartmouth Bridge Commission (the "Commission"). Significant traffic congestion existed at both bridges during the peak hour traffic periods, prior to completion of the Third Lane Project, resulting in increased fuel consumption, carbon monoxide emissions and noise levels, as well as longer trip times by about 20 minutes. The cross harbour traffic capacity had been reached on the bridges. The two bridges form primary links between Halifax and Dartmouth and indeed are key components of the regional roadway network. The Commission retained O'Halloran Campbell Consultants Limited in the early 1990's to evaluate cross harbour traffic patterns, capacity and ways of increasing traffic capacity. The conclusion was that the two bridges, the Angus L. Macdonald Bridge and the A. Murray MacKay Bridge, had reached their peak hour capacity and that further traffic growth could either be achieved by off-peak traffic growth, construction of a third bridge, or reconstruction of the two-lane Macdonald Bridge to create a third lane which would be reversible. It was concluded that the best option for increasing capacity was to widen the bridge to implement a third reversible lane and cantilever the sidewalk outside the stiffening trusses. O'Halloran Campbell had also inspected and investigated the condition of the concrete deck on the Approach Spans of the Macdonald Bridge and concluded that the concrete had deteriorated significantly to the point that it would reach the end of its useful life before the year 2000. The Commission began making plans to replace the concrete deck on the Approach Spans of the Macdonald Bridge, and design was started. Later, the Commission decided that it would widen the bridge to three lanes and add a new bikeway in one expanded project, rather than two projects carried out five years apart, to minimise disruption to the travelling public. (Author/publisher)
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