Canada’s transportation watchdog mechanical issues and track conditions contributed to the train derailment that sent 14 cars from the tracks in the heart of Strathroy last summer.
Mechanical issues, track conditions, caused Strathroy train derailment
The Transportation Safety Board was called in to investigate after a CN freight train derailed near the Metcalfe Street West crossing just after 4 a.m. July 19, 2017. One of the 14 cars that went off the tracks was an empty, dangerous-goods tank that recently had transported liquefied petroleum gas.
Though the tank car came to rest on its side, no dangerous goods were released and no one was injured.
In its report, released Tuesday, Transportation Safety Board investigators found a wheel on the 109th car in the train – one loaded with cement – slipped off the rail during a slight left curve west of the Carroll Street crossing.
The wheels on the residue tank car behind it also derailed, investigators found. Both cars’ wheels stayed off the tracks for nearly two kilometres until the locomotive crossed at Caradoc Street, the Transportation Safety Board report said.
When the cement car reached the crossing, its wheel went back onto the tracks. The residue tank car’s wheels did not.
Once the train reached the VIA Rail station, the residue tank car separated from the cement car ahead of it, causing 13 more cars to derail in the town’s core. The dangerous goods car was several cars behind the ones that derailed first.
The Transportation Safety Board report found there were several “non-condemnable” factors that caused the derailment.
The clearance on the cement car’s mechanism, that limits so-called rock and roll motion, was excessive. It made it easier for the car’s wheel to leave the track.
Other parts on the cement car that deal with friction and lateral swing contributed to the derailment, the report said.
There also were issues with the tracks themselves.
Unusually high rainfall in the three months before the incident likely deteriorated track surface and crossing conditions where the cement car’s wheel first left the rail, the report said.
The train – which was nearly three kilometres long – had been heading from the CN yard in Vaughan to Sarnia when it derailed west of London.
The Transportation Safety Board said CN bought special tools and equipment for its Vaughan yard to fix trucks like the one that caused the derailment. Maintenance crews at the yard also now were paying closer attention to specific parts of cars – the ones that should have prevented the freight train from derailing – in their daily inspections, the report said.
The Transportation Safety Board is an independent agency that investigates marine, pipeline, railway and aviation incidents. The agency offers safety recommendations and does not assign blame or determine civil or criminal liability.