Ile-aux-Tourtes Bridge Reconstruction

The 2021 full closure is what forced the decision. Corroded prestressing tendons and deteriorated deck sections on the 1965 Ile-aux-Tourtes Bridge stranded West Island commuters, and Quebec stopped patching.

The existing 2 km structure carries Autoroute 40, the Trans-Canada, across Lac des Deux Montagnes between Senneville on Montreal’s West Island and Vaudreuil-Dorion. Roughly 87,000 vehicles a day use it. A decade of emergency closures, partial lane shutdowns and stabilisation contracts preceded the replacement decision, and the bridge had become a standing example of what deferred maintenance on a post-war concrete crossing eventually costs.

Project Scope

Two separate parallel structures replace the single span, three lanes in each direction plus a two-way multi-purpose path and shoulders sized for bus operation. The pylons carry a sail-motif architectural treatment. Groupe Nouveau Pont de l’Ile-aux-Tourtes, a consortium of Dragados Canada, Roxboro Excavation and Construction Demathieu & Bard, holds the contract, awarded 17 April 2023. AGF Group supplies reinforcing steel. The westbound structure is scheduled to begin opening by the end of 2026 and the eastbound by the end of 2027. Deconstruction of the 1965 bridge runs to 2029, with landscaping and final works through 2030.

The C$2.3 billion figure is the programme total: design, construction, financing, demolition of the existing bridge and landscaping through 2030. It is not a construction contract sum, and earlier estimates were materially lower before the 2021 emergency works reset the scope. Delivery is design-build-finance rather than a P3 concession. Quebec funds the project entirely; the private finance component is a payment structure, not a toll or availability-payment arrangement.

Why It Matters

Ile-aux-Tourtes is the test case for Quebec’s alternative-delivery model on a major river crossing, and the province has been explicit that it chose DBF to transfer schedule risk without giving up ownership or revenue. Whether that holds through the demolition phase is the open question, because taking down a 1965 bridge next to a live one you just built is where these jobs usually find their surprises.

For anyone working the Montreal market, the staged opening is the thing to plan around. Westbound traffic moves onto new steel before the eastbound structure exists, which means two years of traffic management on a corridor that has already spent a decade in restriction.

Project Team & Details