OTTAWA -- As a major winter storm approached the Capital Wednesday afternoon, transit riders on the LRT were once again forced off of their trains and onto replacement buses after a problem with a piece of the overhead power system.

"One of the components on the overhead catenary system has become loose east of St. Laurent Station. As a result, trains are unable to proceed," Transportation General Manager John Manconi said in a memo, sent at around 4:35 p.m. Wednesday. "Crews have been dispatched to investigate and assess the work required to make repairs."

The overhead catenary system is what powers the train. Wires are supported above the tracks. Power runs from the cables to the train through a roof-mounted device called a pantograph. It's unclear which part of the overhead system came loose.

Manconi sent a followup just before 7:00 p.m. Wednesday to say repairs were getting underway.

"Repairs are about to begin on the overhead catenary system," Manconi said. "Train service continues to run from Tunney’s to Hurdman Station. Bus service continues to run between Hurdman and Blair Station.

"As soon as repairs and testing is complete, train service will resume along the full length of the line."

A tweet sent out at 12:35 a.m. Thursday said full service had been restored.

Trains were first stopped from St. Laurent to Blair, but OC Transpo later extended the line closure to Hurdman.

Manconi said passengers had to be evacuated "from the train [east of St. Laurent] to the buses that are there to accommodate them."

Later, Manconi said another stopped train east of Tremblay Station was being evacuated.

"Customers will exit the stopped vehicle, and be transported on another train to the next station," Manconi said.

Manconi also said a passenger on the train asked for medical assistance and Ottawa Paramedics were called, but he said it was "not related to the incident."

R1 buses implemented as line closure extends to Hurdman

R1 bus service has been implemented between Hurdman and Blair Stations.

S1 service, which runs during the afternoon peak period, was cancelled to provide buses for R1 service.

Trains continue to run between Tunney's Pasture and Hurdman.

Riders react

Speaking on Newstalk 580 CFRA's Ottawa Now with Kristy Cameron, Citizen Transit Commissioner Sarah Wright-Gilbert said she's concerned about what will happen Thursday.

"The storm hasn't even really started. I mean it is snowing but it's Ottawa and it's not the heavy snow we were expecting,” she said. “I'm concerned now about what tomorrow will bring us."

A winter storm warning had initially called for up to 40 cm of snow by Thursday night, but late Wednesday, the forecast changed to 15 to 25 cm of snow with several hours of freezing rain and some rain possible.

Wright-Gilbert later Tweeted to say she does not believe Rideau Transit Maintenance can keep the system running.

In a memo just moments before the delay on the LRT Wednesday afternoon, Manconi said OC Transpo's "severe weather plan" had been launched, which includes what he called a "detailed" plan from Rideau Transit Maintenance for the LRT.

Passengers whose train rides were interrupted reacted to the delays on social media.

Similar issue in January

The LRT experienced a similar issue six weeks ago, not far from where Wednesday's problem occurred.

An overhead wire came loose and fell onto a train as it entered St. Laurent Station on Jan. 16, leading to the longest delay on Line 1 to date. RTM crews worked overnight to repair the system. It was approximately 18 hours before full service was restored.

Officials apologized at a press conference the next day.