OC Transpo Faces Uncertain Timeline for Full O-Train Service Restoration
OC Transpo officials have acknowledged progress in addressing a critical axle bearing issue that has sidelined the majority of the O-Train fleet, but they remain unable to provide a definitive timeline for the return to full service. The transit authority currently operates with only 18 of its 60 train cars available, significantly impacting daily commuter capacity.
Technical Details of the Spalling Problem
During a technical briefing at Ottawa City Hall, interim general manager Troy Charter explained the mechanical failure known as "spalling." This occurs when metal flakes break away from the interior surface of the bearing, contaminating the lubricating grease and preventing smooth rotation. "This degradation can ultimately lead to a failure," Charter warned, emphasizing the seriousness of the issue.
Each O-Train vehicle contains 10 axles, with each axle featuring a pair of cartridge bearing assemblies (CBAs), totaling 20 per train car. The transit authority has removed every train car that has exceeded 100,000 kilometers from service for inspection and replacement of these critical components.
Repair Progress and Operational Impacts
According to OC Transpo chief engineer Marko Kroenke, maintenance teams have replaced 24 CBAs since the problem was identified during routine inspections. Of these replacements, spalling was detected on eight assemblies. The initial inspection examined eight CBAs and found spalling on half of them, indicating a widespread concern.
The current repair pace allows for replacement of CBAs on two axles per day, though Charter declined to specify how long the complete fleet restoration might require. The transit authority normally operates with 26 train cars (13 double-car trains) to handle typical daily ridership volumes, meaning current service operates at approximately 70% reduced capacity.
Separate from Previous Derailment Issues
Charter clarified that this spalling problem represents a new and distinct issue from the cartridge bearing assembly problems that caused two derailments in 2021. "We've had two derailments here, we've had issues with the cartridge bearing assembly previously, so we're going to be very cautious in our approach," he stated, highlighting the transit authority's conservative response to mechanical concerns.
The number of available train cars continues to fluctuate due to routine maintenance requirements and unexpected mechanical issues that temporarily remove vehicles from service. While OC Transpo had anticipated having 20 train cars available this week, only 18 were operational as of Tuesday's briefing.
Potential Impact on LRT Expansion Timeline
Perhaps most significantly, transit officials indicated it remains "too early to tell" what impacts this service disruption might have on the anticipated opening of the LRT east extension to Orléans. This long-anticipated rail extension was projected to open in the first quarter of 2026, but the current mechanical challenges could potentially affect those plans.
The ongoing repairs represent another chapter in the O-Train's mechanical challenges, coming just years after the 2021 derailments that also involved cartridge bearing assemblies. Transit authorities continue to balance mechanical safety concerns with the operational demands of Ottawa's growing public transit system.
