Travelling eastbound on Highway 20? Your commute is about to get even more gruelling

Transports Qubecwants you to know the traffic nightmare is nigh.

Starting Sunday, one eastboundlane ofHighway 20 fromthe Turcot Interchange heading towards the Ville-Marie Expressway will be closed.

That means if you're heading downtown from the western part of the island, your commute is boundto take longer.

Officials can't say just how long, but they expect traffic to be backed upwest ofthe Saint-Pierre Interchange in Lachine. An estimated 3,600 cars travel through the interchange during the morning rush hour.

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Their warning: plana new route, change your schedule,take public transit, or be prepared tosit in traffic.

Transport ministry officialsdo suggest two detour routes, which both employ city streets in the Sud-Ouest borough:

• East alongNotre-Dame Street to St-RmiStreet, then north to St-Jacques Street.
• St-Patrick Street eastbound along the Lachine Canal into the city.

Sylvie Gervais ofKPH Turcot, the consortium in charge of building the new Turcot Interchange, saidtraffic lights will be adjusted, and theconfiguration of intersections and lanes in the areas will be changed in order to keep trafficflowing through those neighbourhoods.

Tearing down the Ville-Marie

The lane closure is necessary in order to prepare two new lanes to access downtown, which will be part of the eventual replacement for theVille-MarieExpressway.Those lanes, which will becalled Route 136,will open in mid-November.

The Ville-Marie is a four-lane highway.Route 136 will eventually also have four lanes, butonly two will be in place when itopens.

That's because there's no room for the other two right now withthe Ville-Marieexpresswayin the way. The distance between it and Route 136 is between 0.8 and 2.8 metres in some places, which isnarrower than a typical three-metre-wide lane of traffic.

The three-kilometre stretchof theVille-Mariefrom theTurcotto a point nearthe Guy Street exitwill be dismantledstarting in November.

On weekdays, the work will take place from 6 a.m. to 7 p.m. On weekends, it will wrap up at 11 p.m.

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For 15 weekends, Route 136 will be closed in order to tear down specific parts of theVille-Marie, meaning there will be no access to downtown from the west along that stretch of highway.

But once itis torn down,crews will build the two other lanes for Route 136. They should open in 2018.

Public transit options

Late this summer,STM announced the measures it will be undertaking to mitigate the traffic challenges, including additional trips duringrush hour onbus routesthat serve the Angrignon and Lionel-GroulxMetrostations and express bus routesfrom the West Island.

And even though the bus lanes on the highway end well before the Turcot Yard, the STM believes taking the bus will still be fasterthan driving.

"We will save enough time to be competitive with anyone taking their car," said STM spokesmanAlain Labelle.

As well, during rush hour anothertrain will be added to the Metro's Green line, which represents 4,000 spaces for commuters.

As for commuter trains,Sandra Sultana, a memberof theTurcotproject build phase team at the Transport Ministry,said while the MTQ lookedinto it, it wasn't possible to increase the number of trains serving the west end of the island.

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