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Deconstruction starts above the St. Lawrence River

8 June 2021

In the coming weeks, a number of pieces of marine equipment will begin their voyage on the St. Lawrence River to perform various tasks to deconstruct the original Champlain Bridge.

Photo: lowering of a modular steel truss

The Nouvel Horizon Saint-Laurent (NHSL) Corporation must remove over 50 modular steel trusses weighing 56,000 kg each using cranes on the bridge deck and from barges. NHSL must also take down 30 spans with a system of platforms attached to lifting towers on a catamaran barge. The piers (the legs of the bridge) and the footings (the underwater feet of the bridge) will also be deconstructed while the spans are removed.
 
A colossal operation that takes a “River Giant” and 12 barges
The different stages of this process will require our “River Giant” along with 12 barges. Different caissons are nested into each other to create the required shape for each barge depending on the type of work it has to do. 

Photo: The “River Giant” barge

  • Pier deconstruction: Two side-by-side barges measuring 210 feet by 144 feet to hold the machinery.
  • Footing deconstruction: Two barges assembled into a “C” shape will surround the footings, which will be retained with sheet piles.
  • Concrete removal: Three rectangular-shaped barges will be dedicated to removing the concrete in addition to helping position the River Giant under each span to be deconstructed. Two winches will be attached to each of these barges to help pull the catamaran barge into position—within an accuracy of ±15 cm—in the strong current of four to six knots. 

Photo: Barge used for the footing deconstruction

Marine work zone under the original Champlain Bridge
Marine work is being done between Île des Sœurs and the St. Lawrence Seaway dike. Due to the presence of large marine equipment and barges that will be travelling quite often in the area, a boating advisory has been issued.

This means that the boating area under the original Champlain Bridge is considered a marine work zone. It is therefore important for boaters to proceed with caution when travelling near and under the bridge.