The botched inspection of an original Expo Line train switch, which should have been replaced more than a year earlier, led to a rare SkyTrain derailment, according to a draft investigation report obtained under freedom of information law.
The May 30, 2022 incident near Surrey’s Scott Road station disrupted service for 24 hours.
The heavily censored September 2022 B.C. Rapid Transit Co. report, titled “Derailment Investigation at Switch DC 47,” said the root cause was worn lateral surfaces and elongated bolt holes at a bolt connection, combined with poor bolt installation techniques.
The internal investigation identified five factors that led to the derailment, including inspections on May 28 and 29, 2022 that “did not record findings” and “did not capture the condition of the bolt.”
The switch is one of 124 on the mainline that enables a train to move from one set of tracks to another. It was due for annual inspection on May 18, 2022, but other urgent work took priority.
Additionally, the 1989-installed switch had been scheduled for replacement in the first quarter of 2021, but COVID-19 restrictions impacted plans and emergency work order changes put other repairs ahead in the queue.
At the time of the report, there were 3,092 open work orders in the SkyTrain guideway department.
Deficient quality control, training and resources also contributed to the incident.
“There was no document provided to verify critical components are installed correctly to the manufacturer specifications and aligned with requirements from the Railway Act,” the report said.
The switch’s last annual inspection was July 9, 2021. Had the May 18, 2022 inspection occurred, technicians would have reassembled the components with new bolts. “This had the potential to have addressed the failed K-plate bolts,” the report said.
In 2021, there were eight work orders for broken K-plate bolts across the entire SkyTrain system. Three of them were on DC 47, including two that broke at the same time.
“There were previous incidents at DC 47, but no technical investigation was completed on previous broken bolt incidents.” The next sentence was censored.
The report said the incident began at 7:40 p.m. on May 30, 2022, when the train operations centre received a fault code from the automated train. Two minutes later, a passenger reported a burning smell via the intercom at Scott Road station. Train operations tried to route the train to Columbia station, but it did not move as commanded. An attendant was directed to walk out to the track and check the switch.
The attendant reported back that the switch was “disturbed and a ‘big chunk of the train has fallen off’.” The incident was declared a derailment at 8:01 p.m. “Work zone and power isolation were in place to off-load passengers safely to Scott Road station.”
No injuries were reported.
The four-car, Mark II train had been travelling at approximately 69 kilometres per hour at the time of the incident. Cars 313 and 314 passed through the switch, but the frog turnout failed to remain locked. As a result, both truck sets on car 317 and truck set 1 on car 318 were derailed and made contact with the median parapet structure, travelling approximately 75 metres to the north until coming to rest.
TransLink’s communications department originally downplayed the severity of the derailment and how close it was to calamity, by calling the incident a “track issue” and “stalled train” before settling on the euphemism “partially dislodged.”
The draft report was dated Sept. 23, 2022, five days before the Sept. 28, 2022 TransLink board meeting where operations vice-president Mike Richard used “train dislodgement” during his presentation.
There are previous reports of SkyTrain derailments in 2010 and 2017.
SkyTrain is running service on a single track until July 31 between Scott Road and King George stations in order to replace two switches near Gateway station.
Editor's note: This article previously described the SkyTrain as having Mark III cars. They are Mark II cars.
