OTTAWA -- The City of Ottawa says it agrees with the Transportation Safety Board of Canada that the risk mitigation regime on Ottawa's LRT is insufficient and they're telling the Rideau Transit Group to explore the idea of adding heat detectors on the trains.

In a memo sent Tuesday afternoon, City Manager Steve Kanellakos responded to a rail safety advisory letter sent by the TSB on Monday. The TSB said that the LRT train that derailed outside Tunney's Pasture Station on Aug. 8 had experienced problems several hours before and that a wheel on one of the cars had severed from its axle because of what it called a "previously undetected catastrophic roller bearing failure and subsequent axle journal burn-off."

The TSB noted that Ottawa's LRT trains do not have heat detection systems which might have caught the overheated axle before a problem occurred and that the strategy of mitigating these problems through routine inspection wasn't good enough.

Kanellakos agreed.

"While a limited number of urban light rail systems include this feature, it is not consistently applied on Canadian urban light rail systems. Alstom’s maintenance regime should manage and mitigate this risk, according to their established practices,” Kanellakos wrote. “The City and the TSB have now determined that these practices are insufficient. In reviewing RTG’s safety documentation and the recent derailment, the TSB specifically notes in the RSA letter that the current mitigations for a roller bearing failure have proven to be insufficient and this is the area that RTG needs to address with Alstom.”

He said that the city is now asking RTG to find a solution to detect these issues before they occur.

"[T]he City will be using our rights under the Project Agreement, to require RTG to explore solutions that would provide an early detection of bearing failures," Kanellakos wrote. "As noted in the TSB letter, the arrangement of bearings precludes effective visual inspection and temperatures cannot be monitored by traditional wayside hot bearing detectors (heat detection units mounted at track level)."

Kanellakos said a final determination of the root cause for this failure is required from RTG and their subcontractor to determine the repairs and mitigation strategies that are required.

The Confederation Line was shut down for five days following the Aug. 8 derailment and nine additional train cars had to undergo additional maintenance to repair loose axle bearings