MONTREAL - It's been postponed twice, but construction work requiring the weekend closure of the Champlain Bridge will finally happen this weekend.

Starting at 10 p.m. Friday August 19 multiple lanes on the Champlain Bridge will be closed.

For most of the weekend until 5 a.m. Monday August 22 two lanes will be open coming into Montreal with one lane heading to the South Shore.

The lanes will also be narrower than normal, at just 3.3 metres wide, so trucks should another route to and from the South Shore.

Drivers looking for an alternative in the seemingly neverending Detour De L'ile should head east to the Jacques Cartier or Victoria Bridge.

However, because of this weekend's NASCAR races, the hours of travel on the Victoria Bridge are changing slightly on Friday.

Motorists using the bridge to get to the South Shore on Friday will only have three hours, from 3 p.m. to 6 p.m., where both lanes are going their way.

After that the Victoria Bridge will be one lane in each direction.

Turcot Interchange

A key westbound stretch of the Turcot interchange will be off-limits starting midnight Friday.

When the clock ticks past 11:59 p.m. Friday August 19, the single lane connecting the Ville Marie Expressway West (A720) to the Turcot yards will be shut down.

Instead drivers will have to detour north on Decarie Expressway, then loop around at Cote-St-Luc St., head south on Decarie and enter the 20 West.

Construction crews are expected to be at work until noon on Sunday, and if they don't finish, the same closure will be in effect next weekend.

Transport Quebec is advising all weekend drivers to check its 511 website.