Southbound Champlain Bridge closed this weekend

The southbound Champlain Bridge will be closed this weekend as part of work to finish the Nuns’ Island Bridge. The closure will cause most of the traffic headaches on the July 31 to Aug. 2 weekend. Here is what you need to know: Southbound traffic on Highway

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15 will be closed from the Turcot Interchange over the bridge to Brossard from Friday at 10 p.m. to Monday at 5 a.m. The suggested detour is via the Jacques-cartier Bridge, since the Mercier Bridge will be limited to one lane in each direction.

For those living on Nuns’ Island,

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the suggested detour is via the Bonaventure Expressway. As part of the closure, the entrances to Highway 20 West and Highway 15 South from the Décarie Expressway will also be closed. The Ville-marie Expressway will still be accessible from Décarie.

The Champlain Bridge-bound

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Bonaventure Expressway will also be closed at Exit 2 (Pierre-dupuy Ave., Montreal Casino).

Work on the Turcot will require

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the complete closure of Highway 15 North from the Turcot Interchange (where it meets Highway 20) to the entrance for Sherbrooke St. W. from Friday at 10 p.m. to Monday at 5 a.m. Cars will be detoured to Highway 20 West, and the suggested detour is via Angrignon Blvd. The Décarie Expressway entrance from Highway 20 East will be closed, as will the ramp from the Ville-marie Expressway to Highway 15 North.

The service road for Highway

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40 West will be closed from the entrance for St-jean Blvd. to the exit for the same street from Friday at 10 p.m. to Monday at 5 a.m. as part of work on the Réseau express métropolitain.

Route 335 North will be closed

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from Saulnier St. to the service road for Highway 440 West from Friday at 11 p.m. to Monday at 5 a.m.