On Monday, Sept 14, 2026, engineers hired by City of Montreal released a recommendation to dismantle the Rosemont‑Van Horne viaduct and replace it with an underground passage beneath the Canadian Pacific railway line.
The viaduct, an aging overpass that spans the CP rail corridor in the Rosemont district, has been under municipal review as part of a broader assessment of infrastructure condition. City officials have indicated that the structure’s age and maintenance requirements prompted the evaluation.
The engineering report proposes a tunnel that would run beneath the active rail line, allowing traffic that currently uses the viaduct to be rerouted underground. The plan calls for removal of the existing elevated structure and construction of a new subterranean corridor designed to meet modern safety and capacity standards.
The recommendation comes as the city continues to weigh options for long‑term transportation planning in the area. If adopted, the demolition and tunnel project would represent a significant alteration to the local streetscape and could affect traffic patterns during construction.
The city has not yet announced a timeline for decision‑making or funding, but the engineering study provides the technical basis for any future action. Officials are expected to review the proposal in upcoming council sessions.
The Rosemont‑Van Horne overpass spans a busy Canadian Pacific corridor that carries freight traffic across the city. Maintaining an elevated structure above active tracks poses operational constraints, and city engineers note that an underground route would separate road and rail movements, reducing interference between the two systems.
City officials indicated that the study does not yet include a cost estimate, but the recommendation is intended to inform future budgeting and planning. Public consultations and detailed design work are expected to follow if the council decides to move forward with the demolition and tunnel construction.