Duplessis Bridge, Road bridge over the Saint-Maurice River in Trois-Rivières, Canada

Duplessis Bridge is a road bridge made of two separate steel spans crossing the Saint-Maurice River at Trois-Rivières by way of Île Saint-Christophe. The west span, 405.4 m long, runs from Trois-Rivières to the island; the east span, 195 m long, reaches Cap-de-la-Madeleine. Its deck rests on two full steel beams 9.75 m apart, with two 1.5 m sidewalks, giving a total width of 12.8 m.

Construction began on 28 June 1946 and the bridge opened to traffic in December 1947, at a cost of $2,230,000. It was inaugurated on 6 June 1948 by Premier Maurice Duplessis. Cracks appeared in February 1950, and on 31 January 1951, at about −30 °C, four spans of the west section collapsed under the bridge's own weight, killing four people. It reopened on 12 November 1953.

The bridge bears the name of Maurice Duplessis, a former Premier of Quebec who maintained substantial influence in the region's development.

The bridge is open to both pedestrians and vehicles with clear pathways for safe passage. Access is straightforward and does not require special arrangements to cross.

The 1951 collapse happened around 2:55 a.m. in extreme cold of −30 to −32 °C, when steel toughness drops; four spans of the west section fell into the river and four people died. The rebuilt bridge, opened on 12 November 1953, used four steel beams instead of two plus 82 reinforcement beams.