Commuters woke up to a nightmare scenario on Thursday after service on the entire GO Transit Milton line and at Hamilton GO station were shuttered due to a rail strike.

Metrolinx announced the closure late Wednesday evening, preemptively cancelling service in advance of a Canadian National Railway and Canadian Pacific Kansas City worker lockout. 

The work stoppage became official at 12:01 a.m. Thursday morning after negotiations with the union representing roughly 9,300 rail employees failed to reach an agreement, and the employer locked out its workers.

Metrolinx has released a statement notifying passengers that "as a result of the ongoing labour disruption, GO train services on the Milton line and at Hamilton GO station are temporarily suspended due to the interruption of rail traffic services provided by Canadian Pacific Kansas City."

The transit agency assured passengers that "all other GO lines, the UP Express and Lakeshore West line stations are not impacted," though it's little consolation to the thousands of daily riders who rely on the Milton line and Hamilton GO station.

Only the Milton line and Hamilton GO station will be affected. Those trains are dispatched by CPKC rail traffic controllers (RTCs), who were also locked out by CPKC. All other trains will run as scheduled.

— Gail Pawis (@pawsitivityplus) August 22, 2024

Over 8,000 daily riders are expected to be affected by the outage, and are advised to take alternate routes where available. Milton passengers can use the Lakeshore West or Kitchener lines, while passengers relying on Hamilton GO can get to trains by travelling to West Harbour or Aldershot GO stations.

Milton GO riders, please use the Kitchener or Lakeshore West lines as alternates.

Hamilton GO Centre has no service. Use West Harbour GO ad an alternate https://t.co/zOPPtk2zvE

— Transit News Network (@TransitNews1) August 22, 2024

The unprecedented work stoppage is causing commuter headaches far beyond the Greater Toronto Area, affecting transit services across the continent.

But it is also expected to cause major supply chain issues. Many businesses say they will be completely unable to operate, supply chains will grind to a halt, and the trucking industry will face additional demand.