More than 32,000 rail commuters across the country will have to find new routes to the office if a work stoppage kicks off at Canadian Pacific Kansas City Ltd. this week.

Transit authorities say select commuter lines that run on CPKC tracks in Toronto, Montreal and Vancouver will be suspended should dispatchers walk off the job at 12:01 a.m. EDT on Thursday alongside 3,200 other workers.

The railway has said it will lock out employees unless a new contract is reached or the Teamsters Canada Rail Conference agrees to binding arbitration 鈥� a path the union has rejected. The Teamsters have also issued a 72-hour strike notice, which would kick in at the same time.

A phased shutdown of the networks at both CPKC and Canadian National Railway Co. is already underway as the clock ticks down on negotiations between both companies and the union. Canadian Pacific barred virtually all new shipments on Tuesday morning, with CN planning to do the same Wednesday to avoid leaving any goods stranded on the tracks.

The commuter lines affected by the potential work stoppage are TransLink鈥檚 West Coast Express in the Vancouver area, Metrolinx鈥檚 Milton line and the Lakeshore line鈥檚 Hamilton GO station in the Greater Toronto Area, and Exo鈥檚 Candiac, Saint-J茅r么me and Vaudreuil/Hudson lines in the Montreal area.

鈥淲ithout the work of the CPKC rail traffic controllers, our trains on these three lines would be unable to run,鈥� said Exo spokesman Eric Edstr枚m in an email in French.

鈥淭he bus shuttles that will be offered will not be able to compensate for the entire service of the three affected train lines.鈥�

The three Montreal lines account for 21,000 of the impacted daily riders, while Greater Toronto would see about 8,100 customers sidelined, according to the transit agencies. In Metro Vancouver, more than 3,000 passengers take the West Coast Express each day.

TransLink said it will provide customer updates as the situation unfolds. Metrolinx is pointing Toronto-area riders to alternate routes and stations, while Exo said it is working on alternative bus services into Montreal.

The impact on commuter lines is limited to routes running on CPKC-owned tracks because dispatchers at CN, which hosts a greater number of passenger trains, are not part of the bargaining process and would not take part in a work stoppage.

The Teamsters represent some 80 CPKC rail traffic controllers negotiating for a contract 鈥� distinct from the company鈥檚 main group of engineers, conductors and yard workers.

A shutdown by 9,300 employees at CN and CPKC would be unprecedented, marking the first-ever simultaneous work stoppage at the country鈥檚 biggest rail companies, experts say. Their trains haul a combined $1 billion worth of goods per day, from canola to consumer electronics, according to the Railway Association of Canada.

Already, the U.S.-based CSX and Norfolk Southern railways have closed their gates to most cross-border shipments, while shipping giants such as Hapag-Lloyd have made 鈥渃ontingency plans鈥� as others reroute cargo.

More than 100 industry groups and local chambers of commerce have called on the prime minister for government intervention, warning that key links in the country鈥檚 supply chain are set to snap.

Labour Minister Steven MacKinnon planned to meet with CN and union representatives in Montreal on Tuesday, and with CPKC and the Teamsters in Calgary on Wednesday.

MacKinnon, who stepped into the minister鈥檚 role barely four weeks ago, has repeatedly stressed that the parties must hammer out a deal themselves rather than rely on federal intervention, such as back-to-work legislation.

All sides said this week they remain far apart, with wages and scheduling as key stumbling blocks.

If they can鈥檛 reach a tentative deal, some Via Rail passengers will also be affected.

Canadian Pacific owns two sections of track in Ontario where Via trains run, including a nearly 480-kilometre stretch between Sudbury and White River. The train, which runs three times a week, would be cancelled 鈥渨ithout alternative transportation鈥� until the labour dispute ends, said Via spokeswoman Jamie Orchard.

鈥淚mpacted customers on this route will be contacted directly if the work stoppage is confirmed. They will also be able to autonomously modify their reservation or opt for a full refund at no cost on viarail.ca,鈥� she said in an email.

The Crown corporation is also working with CPKC to maintain access to a one-kilometre section in Smiths Falls, Ont., that its cars traverse on multiple daily trips between Toronto and Ottawa, Orchard said.

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