Submission #21 CLOSE
Sturgess Architecture (Calgary) with Halcrow Yolles, IBI Group, Stebnicki + Partners, Derek Besant
The design of St. PatrickÃs Bridge is a response to the site, the condition of the Bow River and the two paths taken by the pedestrian and the bicyclist.†The Bow River is one of North AmericaÃs premier trout fly-fishing rivers. As a fly-fishing line is cast, the path it travels inspired the design of the bridgeÃs supporting arches. Further geometric exploration refined the idea so that it became a whip stitch and then a series of parabolas.†The bridge has two separate and linked deck systems. One is for the pedestrian, following a graceful curve; and one for the cyclist, reflecting the speed and trajectory of the path it travels, climbing to a higher grade above the pedestrian path and creating shelter beneath it. Both decks follow a gentle ëSà curve, responding to the location and size of the two river channels. The paths are counterbalanced by the opposing ribbon arches that support them. The arches and paths converge on St. PatrickÃs Island.†On St. PatrickÃs Island there is a viewpoint ñ the Bowsprit ñ that establishes a place to step off the pathway and view the city to the west. A ramp leads down on the east side to the island and the pathway system. At the centre of the south curve, there is a resting place, above the river and under the bicycle path. From the benches located here there are juxtaposed views: to the West, the evolving downtown, the 5th Avenue axis, the LRT and vehicular bridges. To the East, the view is of Fort Calgary, and has barely changed over the last 100 years.
The plan of the bridge is angled from the southwest to northeast to best connect from the south bank – the point between Fort Calgary and the Rivers District, touching down on St. PatrickÃs Island and landing on the north bank close to the LRT station and its pedestrian bridge over Memorial Drive.
A unique feature of the bridge is that its structural efficiency and delicate ribbon arches are achieved by counterbalancing the forces of the arch and pathways. A second innovation is the balance achieved between the suspended pedestrian bridge deck and the bicycle deck above.
