Weekend highway closures hit Montreal area: Honoré-Mercier, A-40, A-25, Route 158
Mobilité Montréal warns of major road work and closures from Friday through Monday affecting commuters across the region, including complete closure of Route 158 in Mirabel.
Sources · Quebec Nouvelles
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Mobilité Montréal announced major road work and closures for the weekend of September 11-14, 2026, urging commuters to plan trips in advance.
Honoré-Mercier Bridge / Route 138: From Saturday 3 a.m. to Monday 5 a.m., one lane on each direction is closed at the end of the Honoré-Mercier between Montreal and Kahnawake. Congestion is expected Saturday and Sunday during daylight hours.
Autoroute 40 / Métropolitaine (Saint-Michel and Pie-IX sectors): From Friday 22 p.m. to Monday 5 a.m., exit 75 (A-19 north, boulevard Saint-Michel / avenue Papineau) is closed on A-40 westbound. Detour: make a U-turn at exit 73 via rue Saint-Hubert. Additional partial closures affect the A-40 west service road (boulevard Crémazie Ouest) with one lane closed on certain sections between boulevard Pie-IX and boulevard Saint-Michel from Friday 23 p.m. through Monday 5 a.m.
Autoroute 25 / Pont Olivier-Charbonneau: Saturday 7 a.m. to 5 p.m., one lane is partially closed northbound on the bridge between Montreal (Rivière-des-Prairies, Pointe-aux-Trembles) and Laval.
Route 158 / Route Sir-Wilfrid-Laurier (Mirabel): From Friday 21 p.m. to Monday 5 a.m., the road is completely closed in both directions between A-15 (des Laurentides) and chemin Saint-Simon. Westbound detour: take the A-15 south exit 35 to A-50 west, then exit 279 to chemin Saint-Simon. Eastbound detour: take A-50 east, exit 292-N to A-15 north, then exit 39 to Route 158 east.
Film production in downtown Montreal Saturday and Sunday will also close rue Union completely (between boulevard René-Lévesque and rue Belmont) and restrict traffic on boulevard Robert-Bourassa northbound and boulevard René-Lévesque in both directions from 4 a.m. to 8 p.m. both days.
The facts
Which roads are closing this weekend in the Montreal area?
Honoré-Mercier Bridge, Autoroute 40, Autoroute 25, and Route 158 in Mirabel all have closures. Additionally, rue Union in downtown Montreal will be completely closed for film production on Saturday, September 5, 2026 and Sunday, September 6, 2026.
When is Route 158 in Mirabel completely closed?
Route 158 is completely closed in both directions between A-15 and chemin Saint-Simon from Friday, September 11, 2026 at 9 p.m. through Monday, September 14, 2026 at 5 a.m.
What is the westbound detour for Route 158?
From Route 158, take the A-15 south exit 35 to A-50 west, then exit 279 to chemin Saint-Simon.
Which exit is closed on Autoroute 40 westbound?
Exit 75 (A-19 north, boulevard Saint-Michel / avenue Papineau) is closed on A-40 westbound from Friday, September 11, 2026 at 10 p.m. through Monday, September 14, 2026 at 5 a.m. Use a U-turn at exit 73 via rue Saint-Hubert to detour.
