After weeks of traffic snarls on the Champlain Bridge, South Shore commuters are preparing for yet another transit hiccup  and this time on the metro.

The 47-year-old yellow metro line, which passes under the St. Lawrence River, is a key artery for South Shore commuters and it's facing some major repairs.

The Montreal Transit Corporation (STM) says workers need to fix micro-cracks that have developed in the tunnel’s concrete ceiling.

Those repairs will require shutting down the metro for a total of 25 weekends in 2014, from March to May and from September to December.

'If there is anything that conflicts with the schedule, the schedule will be postponed'-  Philippe Schnobb, STM chair

Newly appointed STM chair Philippe Schnobb says commuters have nothing to worry about.

“Our priority [is] to make sure that the clients will be able to come to Montreal and to go back home,” he said.

Aside from regular commuting, thousands of tourists and Montrealers rely on the yellow line to access Parc Jean-Drapeau, which is home to music festivals such as Osheaga and Heavy MTL.

When are the repairs?

  • The yellow line will be shut down for a total of 25 weekends.
  • Those weekends will be split into two phases.
  • Part I: From March 8 - May 25, 2014.
  • Part II: From Sept. 13 - Dec. 14, 2014.

Schnobb says the repairs have been specifically scheduled around the busy summer season to avoid conflict.

But the weekend repairs could overlap with some of Parc Jean-Drapeau's summer-long events such as Piknic Electronik.

The popular music festival runs every Sunday from May to September, and draws crowds of sun-seekers, many of whom rely on the metro. 

Schnobb says that if any conflicts do come up, the repair schedule is open to change.

“If there is anything that conflicts with the schedule, the schedule will be postponed. If there is a problem on Champlain Bridge in the middle of the winter, and we need access to the yellow line for a weekend, we will just postpone the works for that weekend,” he said.

“It’s very flexible.”

Shuttle buses provide alternate route

During the weekend repairs, the STM plans to run shuttle buses as another option for commuters. They will run from the Longueuil-Université de Sherbrooke metro station, across the Jacques Cartier Bridge, with a stop at Papineau and at Berri-UQAM station. Another shuttle line will also go directly to Parc Jean-Drapeau.

Schnobb was also careful to point out that there is no concern for the safety of commuters.

“The metro is aging, the system is aging, the tunnels are aging … we have to do that kind of maintenance,” he said.