The Champlain Bridge (French: Pont Champlain) is a steel truss cantilever bridge with approach viaducts constructed of prestressed concrete beams supporting a prestressed concrete deck paved with asphalt. The bridge crosses the Saint Lawrence River and Saint Lawrence Seaway, connecting the Montreal boroughs of Verdun and Le Sud-Ouest to Brossard on the South Shore,
The bridge, with approaches, is approximately 6 km (3.7 mi) in length. When the project began, it was designated as the "Nuns' Island Bridge" because it crosses over Nuns' Island. In 1958, it was officially named the Champlain Bridge in honour of the explorer Samuel de Champlain who founded Quebec City in 1608.
Together with the Jacques Cartier Bridge, it is administered by the Jacques Cartier and Champlain Bridges Incorporated (JCCBI), a federal agency which is a fully owned subsidiary of the Federal Bridge Corporation Limited.
With nearly 160,000 daily crossings, the Champlain Bridge is the busiest bridge in Canada (the Hogg's Hollow bridge system in Toronto is the busiest multi-structure bridge in North America, with four separate bridges averaging a combined 400,000 + vehicles a day through Highway 401).
The Champlain Bridge project was undertaken in 1955 and construction proceeded between 1957 and 1962. The bridge carries six lanes of vehicle traffic; three in each direction. During rush hour one lane of those heading off the island in the morning, and onto the island in the evening, is used as a reserved bus lane for buses to be able to head in the opposite direction. The bridge was opened to traffic in stages as the approaches were completed between June, 1962 and September, 1964. It was subsequently connected to the Bonaventure Expressway, which is part of the north approach to the bridge. The expressway was opened to traffic on April 21, 1967 Approximately 49 million vehicles cross the Champlain Bridge every year, and 196 million people making it one of the busiest bridges in the world. Total length of crossing complex: 14.5 km (9 mi)
- Total bridge length including approaches: 7,412 m (24,318 ft)
- Length: abutment to abutment: 3,440 m (11,290 ft)
- Link of viaduct to Section 1: 2,195 m (7,201 ft)
- Center main cantilevered span: 215 m (705 ft)
- Wellington Street approach: 365 m (1,198 ft)
- Bonaventure Expressway: 4,573 m (15,003 ft)
Just upstream from the bridge is an ice boom, the Champlain Bridge Ice Control Structure.