The next phase of major work on the Turcot Interchange will make it quite difficult to head west.

In six weeks, the St. Jacques St. exit from Highway 720 West will close, as will the ramp connecting to Highway 15 South.

About the same time the Fort St. and the Lucien L'Allier St. entrances to the 720 West will also shut down.

Those closures will last at least one year -- possibly until 2019 -- and will be necessary because drivers coming out of the Ville Marie tunnel will be shifted to the south as they drive on the yet-to-be-completed lanes of Route 136, the lowered replacement for the 720.

Transport Quebec will be adding an entrance to the westbound highway at Rose de Lima to accommodate drivers coming from downtown, since the only other places to access the westbound highway will be at the Papineau Ave. and Viger Ave. entrances.

While part of Rose de Lima was turned into a one-way northbound street from Notre Dame St.. in July, the ministry says that only buses will be allowed to proceed north of St. Jacques St. once the entrance is open.

Drivers who want to use the Rose de Lima entrance will have to access it via St. Antoine St. and the ministry expects the intersection of St. Antoine St. and Rose de Lima will be the site of major congestion for at least a year.

However Route 136 will not be available seven days a week.

Crews will spend half a year demolishing the elevated portion of Highway 720, and estimate it will require 20 to 25 weekend closures of Route 136 in both directions.

Decarie to 20 West

Another major change to come in the Turcot Interchange, either at the end of November or in December, is the reconstruction of the ramp connecting Highway 15 South to Highway 20 West.

That means drivers coming off the Decarie Expressway who want to go west will have to head east on a yet-to-be built ramp that will head to surface streets below the MUHC hospital, then head west on Pullman Blvd. and eventually connect to Highway 20 West in the Turcot Yards.

This surface route will also be used by drivers heading north on Highway 15 who want to head west.

Transport Quebec pulled down the ramp connecting Highway 15 North to Highway 20 West in September.

20 West moving to the north

At some point in the next year the existing Highway 20 Westbound lanes will be eliminated, replaced by a new highway located about 200 metres further north, with many new entrances and exits.

The other major detour will be the demolition of the existing ramp from Highway 20 East to Highway 15 North.

Instead, drivers will have to exit the highway and take Pullman Blvd. to an area near the MUHC hospital, then connect to a new ramp leading to the Decarie Expressway.

Many of these ramps and routes will be temporary roads built so that that drivers can continue to use the Turcot while it is rebuilt.

Public transit a 'necessity'

Sylvie Gervais with contractor KPMG Turcot was succinct in her assessment for drivers over the next year.

“I would say the biggest message that we have to tell everyone is that the upcoming work, road users and motorists will have to rethink their commute. At the moment, public transit is not just an option, I think it’s really a necessity for the next 12 months,” she said.

To that end there will be dedicated bus lanes along Notre Dame St., St. Patrick St., and Sherbrooke St., as well as on Highway 20 between Dorval and Lachine, and throughout the Angrignon interchange.

Transport Quebec has also provided funding to add buses and trains in the areas affected.

More details - including maps - here: