Quebec’s Transport Ministry will repair a cracked steel beam beneath the Honoré-Mercier Bridge this weekend, reducing traffic to a single lane in each direction from Saturday morning until early Monday. Commuters face major congestion heading toward Montreal while officials implement transit workarounds and toll suspensions.
Weekend Repair Work Scheduled for Honoré-Mercier Bridge
The urgent maintenance follows the discovery of a fissure in a steel component supporting the bridge. Late Tuesday evening, Quebec’s Transport Ministry announced an indefinite closure of the left lane for drivers heading toward Montreal, creating immediate commuter headaches for South Shore residents. By Wednesday, officials estimated repairs would take until the end of the week. Crews will now execute the fix from Saturday at 3 a.m. to Monday at 5 a.m., though the ministry noted that unfavourable weather or operational constraints could alter the timeline.
During the weekend intervention, one lane in each direction will remain open on the Honoré-Mercier Bridge and Route 138. Access from Airlie Street toward Route 138 west stays open, but regional congestion is expected. The ministry advises motorists to allow extra time or choose public transit.
Transit Adjustments and Suspended Tolls for Commuters
To mitigate the disruption, the toll on Highway 30 westbound will remain suspended during weekday morning rush hours from 5:30 a.m. to 9:30 a.m. until restrictions lift entirely. The Autorité régionale de transport métropolitain (ARTM) and regional transit network Exo also introduced a temporary special bus route, Line 744, operating between Châteauguay and Delson.
The temporary service makes five stops designed to connect commuters with the Taschereau bus line and the Candiac train. Travellers can also consult Québec 511 to plan alternative routes around the closure.
Structural Safety Assurances Amid Broad Regional Closures
While the cracked beam prompted swift precautionary restrictions, transport officials emphasized that visible wear or corrosion does not dictate overall structural health. The Honoré-Mercier Bridge operates under an ongoing maintenance program featuring regular inspections.
The Mercier Bridge work coincides with a heavy weekend of transportation disruptions across the Montreal area, including partial closures on the Bonaventure Expressway and the Samuel-De Champlain Bridge, as well as nighttime tunnel closures on the Louis-Hippolyte-La Fontaine bridge-tunnel. REM network work will also cause delayed start times to services on October 17 and 18.
Additional Road Closures Across Montreal and Surrounding Areas
Motorists driving through the greater Montreal region this weekend face multiple additional traffic impediments. At the Laurentides Interchange in Montreal, the service lane of the A-15 southbound leading to Rockland Road and Marcel-Laurin Boulevard is closed from Friday at 10 p.m. to Monday at 5 a.m. On the A-10 East Bonaventure towards the Samuel-De Champlain Bridge, drivers will encounter a partial closure of one in two lanes between exits 4 for the A-15 and A-20 and exit 5 for Île-des-Soeurs starting Saturday at 5 a.m. through Monday at 5 a.m. On Sunday between 6 a.m. and 6 p.m., the northbound Samuel-De Champlain Bridge heading toward Montreal will feature a partial closure of the left-hand lane between Route 132 in Brossard and Île-des-Soeurs, with traffic permitted to use the shoulder.
Tunnel and highway connections are also affected. The Louis-Hippolyte-La Fontaine bridge-tunnel southbound is subject to a complete closure between Exit 5 for Sherbrooke Street in Montreal and Route 132 in Longueuil from Friday at 11 p.m. to Saturday at 8 a.m., alongside the closure of Avenue Souligny on Friday starting at 10:30 p.m. between Dickson and Honoré-Beaugrand streets. Elsewhere, the Victoria Bridge maintains a single-lane configuration in each direction at all times due to ongoing work on Rue Bridge.
Suburban routes face targeted disruptions as well. In Vaudreuil-Dorion, the bridge over the River Quinchien on Rue Ouimet between Boulevard de la Cité-des-Jeunes and Chemin Paul-Gérin-Lajoie closes in both directions on Saturday from 8 a.m. to 4 p.m., with traffic diverted via Rue Jeannotte and Avenue Saint-Charles. In Brossard, Route 134 or Boulevard Taschereau utilizes contraflow traffic in the evenings and at night between Avenue Panama/Auteuil and Boulevard Matte until mid-October to facilitate junction resurfacing, accompanied by local cross-street closures and detours. Long-term regional projects continue to impact drivers, including night-time closures on the A-13 Chomedey at the A-520 Côte-de-Liesse junction lasting until November 2, 2026, and the closure of the westbound A-520 access ramp from Roméo-Vachon Boulevard heading south in Dorval until November 11 at 11:59 p.m.
