Five Years, No Root Cause: The Confederation Line's Bearing Problem
A rail system, a wheel bearing, and two French companies who still can't agree on why it keeps failing.
Every time Ottawa's Confederation Line goes down, the explanation eventually lands on the same part: the bearing that connects a wheel to its axle. It happened in 2021. It happened again in 2023, shutting the entire line for nearly a month. It happened again this past January. Five years in, the people responsible for the trains — the manufacturer, the maintainer, and the City — still haven't agreed on why.
Here's what's actually on the record.
The part, and who built it
Ottawa's LRVs are Alstom's Citadis Spirit, a model designed specifically for the Confederation Line and mounted on what Alstom calls an Iponam bogie. Each axle carries two wheel hubs and two cartridge roller bearing assemblies, held together by a large locking nut. According to the Transportation Safety Board of Canada, that cartridge assembly was designed and manufactured by Texelis, a French company based in Limoges, built to Alstom's specification and shipped to Canada for installation.
Both companies are French. Both signed off on the design. Neither has fully owned the failure.
A recurring problem, not a one-off
Failures by year
Laid out by year, the pattern is hard to read as anything but recurring — not a single bad batch of parts, but a fault line that keeps reopening.
What the experts have said
A former director of rail investigations at the TSB put a number on how unusual this is: bearings like these are typically designed for a minimum ten-year service life before failure. Ottawa's started failing inside two.
The TSB's own comparison is worth sitting with. Other cities run Alstom vehicles on similar cartridge assemblies with far fewer defects — Paris and Istanbul among them. What's different in Ottawa, per the TSB, is that our trains are longer, heavier, and carry more passengers at higher speed than those systems, on a bearing cartridge that stayed the same size. A University of Ottawa mechanical engineering professor who reviewed the City's 2023 "root cause review" made a similar point more bluntly: the trains got bigger and heavier, but nobody scaled up the part that has to carry that load — and even a report titled "Root Cause Review" never actually named one.
Not a manufacturing-defect story. A design and accountability story.
That distinction matters for what residents should actually be asking their council for. It's not "find a better supplier." It's: who is responsible for reconciling vehicle design against track design when the two don't agree, and why did it take a public inquiry and five years to get a straight answer on where the fault lines are?
Where things stand
| Question | Status |
|---|---|
| Root cause identified? | No — disputed between Alstom/Texelis (track/wheel-rail interface) and the City (wants axle redesign resumed) |
| Axle redesign ("final fix") | Abandoned by Alstom in May 2024; City has asked for it to resume |
| Restraining rail adjustments | Completed at several curve locations, millimetre-scale shifts |
| Most recent bearing incident | January 21, 2026 — spalling found, high-mileage axles pulled fleet-wide |
| Independent monitoring for bearing temperature | Flagged as absent by the TSB in 2021; status of any fix not confirmed in public reporting reviewed here |
What I'd want confirmed
- Has a bearing-temperature monitoring system — the gap the TSB flagged in 2021 — actually been installed fleet-wide, and when?
- Has the axle redesign the City asked Alstom to resume in 2024 actually restarted, and on what timeline?
- What was the specific cause of the January 2026 spalling, and is it the same failure mode as 2021 and 2023, or a new one?
- Has anyone — the City, Alstom, or an independent body — published a single document that reconciles the competing "track design" and "vehicle design" theories, rather than each party pointing at the other?
Ottawa spent nearly two decades and well over a billion dollars building this system. Five years after opening day, the two companies responsible for its most safety-critical moving part still can't agree on why it keeps breaking. That's not acceptable.







