Draft:Champlain Bridge Ice Structure

This page is about the Ice Control Structure spanning the St. Lawrence River. For the bridge it protects, see Samuel-De Champlain Bridge.

Ice Control Structure is seen in the foreground, upstream of the Samuel-De Champlain Bridge. Both span the St. Lawrence River. Montréal is visible in the background. Photograph taken from Brossard, QC (looking west).

The Ice Control Structure and Samuel-De Champlain Bridge can be seen to the top of the image. North is up, with Montréal on the left and Brossard on the right. The partially-deconstructed former Champlain Bridge is also visible in between the two structures.

The Champlain Bridge Ice Control Structure (French: Estacade du pont Champlain) runs parallel to the Samuel-De Champlain Bridge, traversing the St. Lawrence River 300 m upstream. The Ice Control Structure was constructed in 1964-1965 to control the formation and movement of ice in the Prairie Basin. This helps facilitate navigation to the Port of Montreal and reduces erosion of the islands surrounding Montreal, especially Notre Dame Island and Saint Helen's Island, which were the products of significant land reclamation in preparation for Expo 67.

In the 1990s, a bike path was added to the Ice Control Structure, connecting Nun's Island to the Route verte, which itself runs over the dike of the South Shore Canal

History

Aerial view of the structure, showing the bike path and maintenance road.

The construction of Nun's Island and the expansion of Saint Helen's island for the Expo 67 reduced the width of the the St. Lawrence River, raising fears of negative consequences. The Ice Control Structure was constructed in 1964-1965 to control movement of ice in the river, limiting the risk of ice jams and subsequent flooding. The structure was built and managed by Transport Canada under the direction of the Canadian Coast Guard. In 1998, the Canadian Coast Guard transferred responsibility of the structure to the The Jacques Cartier and Champlain Bridges Incorporated, a Canadian Crown Corporation (French: Les Ponts Jacques Cartier et Champlain Incorporée).

Design

The 2,043 m long and 18 m wide boom spans between Nun's Island and the dike of the St. Lawrence Seaway. It consists of 72 reinforced concrete pillars 10.5 m high, and two abutments. The majority of the structure consists of repeating 27 m spans, with three 53 m spans traversing a deep water channel. Originally, the structure was designed with floating gates in between each span which would ride vertically along heated grooves in the pillars, holding back surface ice. After construction, it became apparent that the large number of closely-spaced pillars themselves were sufficient to retain ice, without the need for moving gates.

In the spring, accumulated ice is released automatically as it melts and breaks up into pieces small enough to fit between the pillars.

The top of the structure features a bike path, which is open to the public, and a maintenance road.

There are also

• Length: 2,040 m
• Bridge deck width: 8.5 m
• Total width: 18.0 m
• Number of pillars: 72
• Water depth: 2-10 m
• Approach length: west side: 400 m, east side: 80 m

The cost of construction in 1956 was around $ 18 million CAD (equivalent to $210 million CAD in 2025).

Future Plans

View from the bike path.

A project to develop a light rail corridor over the structure was explored by the Exo, but was ultimately superseded by the REM, which now runs over the Samuel-De Champlain Bridge.

The 1988-1998 Action Plan of Transports Quebec proposed to redevelop the structure and its approaches to make them suitable for bus transit by the Réseau de transport de Longueuil, which currently uses a dedicated lane on the Samuel-De Champlain Bridge. Despite positive opinions in favor of the project, it was not pursued.