Ongoing, full LRT shutdown blamed on another bearing problem

Ottawa's light rail line is closed until further notice due to its latest problemwith the connections between the trains and their wheels.

In a tweet at about5 p.m. Monday, OC Transposaid LRT servicebetween Tunney's Pasture andBlair stations had stopped and all stations were closed due to a "technical issue."

R1 replacement bus service is running the length ofLRT Line 1 until further notice, OC Transpo said Monday.

OC Transpo general manager of transit services Rene Amilcarsaid Tuesday morning replacement bus service would run every 10 minutes to start the day and every five minutes during peak periods.

What's happening?

In a pair of Monday memos to the mayor and councillors, Amilcarfirst saida routine inspection revealed an issue with a bearing.

She later said that inspector found more grease than there should be on one of the axles under the train that connect to its wheels.

A further look at the axle found "the bearing play was over the threshold at which it could stay in operation," she wrote.

Basically, bearings are inside these LRT wheelsandare both part of what makes them roll and part of the connection between the wheels and train via its axles underneath.

Amilcar said the decision to end servicewas made "in an abundance of caution" and that every single axle on its light rail trains would be inspected. Train-maker Alstom is also inspecting the track.

Past problems

Amilcar said the problem identified Monday is similar to past problems.

Thederailment of atraininAugust 2021 involveda wheel that was severed from the axle due to a "catastrophic bearing failure," according to the Transportation Safety Board (TSB).

In a February 2023 letter to city officials, the TSB saidthe problems that causedthe derailmentin August 2021 and a component failure in July 2022 "continue to pose a risk to safety until the issues are resolved."

Testimony at the LRT public inquirysuggested a larger problem:that the way the wheel meets the rail on sharp curves putstoo much stresson traincomponentsincluding the bearings.

In response to the TSB, Amilcarwrote in a February memo to council that OC Transpohad already undertaken several measures to fix the issues.

These measures included daily inspections of all light rail vehicles and a directive to inspect bearing assemblies every 7,500 kilometres.