Officials still looking into cause of last week's Ottawa LRT shutdown

More than a week after freezing rain halted service on Ottawa's LRT system, officials still don't know the root cause of the outage.

Five trains were stranded on the Confederation Line during the storm last week, stranding passengers and forcing OC Transpo to deploy replacement buses.

"Rideau Transit Group is still working on their investigation into the cause of this disruption," the city's transit general manager Renee Amilcar told transit commission on Thursday.

"Council will be provided with this information once the investigation is complete."

Partial service on the line resumed the day after the outage, and full service resumed the following evening, more than 30 hours after the initial shutdown.

Some passengers who were on the stranded trains for more than two hours complained of a lack of communication.

Amilcar said OC Transpo has reviewed its response on that front.

"I know that we still have room to improve. Our team has reviewed our response. Additional guidance has been provided to rail operators to ensure that customers on trains are frequently informed and updated," she said.

Amilcar said OC Transpo's social media team is reviewing its response to ensure timely responses are provided.

"We apologize for the inconvenience this incident caused our customers," she said.

Rideau Transit Maintenance's CEO said last week the five vehicles stopped when the onboard systems detected power fluctuations from the overhead catenary system.

"When the overhead wire that supplies the power has ice on it, the pantograph on the vehicle is not making good contact, and we see big fluctuations in voltage. When the vehicle sees that, it shuts down to protect itself," Mario Guerra said.

That was a different situation than the freezing rain that led to a six-day shutdown in January. In that case, ice built up on the overhead catenary system. Two trains stopped east of Lees Station due to the frozen wires, and a section of the overhead power system was damaged.

Officials blamed a "unique combination of factors" in that case. Officials released that information more than a month after the shutdown. In February, Rideau Transit Maintenance crews repaired a broken arm that supports the wire in the overhead catenary system near Lees Station.