More weekend closures for Mercier
Traffic control in action as road work continues on the bridge. Expect lane adjustments, delays, and detours directed toward the Champlain Bridge. Shore-bound traffic will still have two open lanes. Courtesy David Lahache
Commuters planning to travel between Montreal and the South Shore this weekend should prepare for significant disruptions.
The Mercier Bridge will be completely closed to Montreal-bound traffic beginning Friday, September 26, at 11 p.m. until Monday, September 29, at 5 a.m. The closure is part of ongoing maintenance and repair work overseen by the provincial Ministry of Transport.
The most critical change for drivers is that no access will be permitted towards Montreal via the Mercier Bridge during this period. Authorities are urging commuters to plan ahead and use the Champlain Bridge or other alternate routes.
Traffic heading in the opposite direction toward Kahnawake and the South Shore will still have access. Two lanes will remain open, but congestion is expected.
In addition, the Airlie Street entrance from LaSalle to Highway 138 West/Mercier Bridge will be closed, preventing direct local access to the bridge. Route 207 will also be under limited access restrictions, reserved only for local traffic.
The Mercier Bridge, built in 1934, is one of the busiest commuter links in the Montreal area. With aging infrastructure and constant heavy use, the structure requires ongoing maintenance to remain safe and functional.
David Lahache, transport coordinator for the Mohawk Council of Kahnawake (MCK) overseeing logistics and communications for the project, explained the reasons behind the work.
“This is part of a scheduled series of maintenance operations. Right now, the work is focused on upkeep, not on major structural safety issues. The goal is to extend the lifespan of the bridge and ensure smoother traffic flow once the project is completed.”
Lahache clarified that while many commuters may feel frustrated by repeated closures, the work is unavoidable.
“The Mercier Bridge is essential for both Montrealers and South Shore communities. Unfortunately, the only way to carry out this kind of maintenance is through partial or full closures. We know it’s inconvenient, but the long-term priority is keeping the bridge safe and reliable.”
For drivers heading into Montreal from the South Shore, the closure will likely mean heavier traffic on the Champlain Bridge and surrounding detour routes. Commuters are urged to avoid Highway 138, Highway 132, and Route 207 entirely if their goal is to access Montreal; those routes will lead directly to closures.
Public transit services are expected to maintain regular schedules, though delays caused by detours are possible.
Lahache noted that his team is working to minimize disruption:
“We’ve coordinated to keep two lanes open for South Shore traffic. That helps balance the flow, but there’s no denying that commuters will feel the impact. We encourage everyone to plan ahead and give themselves extra time.”
The closure is scheduled until Monday, September 29, at 5 a.m., but there is always the possibility the work could finish ahead of schedule. However, officials are quick to warn drivers not to rely on that.
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The bridge has seen multiple closures in recent years as part of a larger rehabilitation program. Lahache explained that this weekend’s closure is essentially “part two” of the work that began last week. Additional maintenance and rehabilitation phases are expected in October and November.
He emphasized the importance of continued investment in this, “Our number one priority is the integrity of the bridge and the safety of the people who use it every day. The work being done now prevents larger problems later.”
