30 December 2004
2003 CPR Derailment
Cause Finally Released
Parry Sound - On
13 Feb 2003 at 8:30 a.m., 21 Canadian Pacific Rail cars left the tracks, near the
Shebeshekong Road Crossing here.
The derailment forced the evacuation of nearby residents.
At the time of the accident, it was minus 27 Celsius, but there was no cold order for trains to slow
down. The train was traveling south at 68 kilometres per hour. The allowed speed is on the tract is
100 kilometres per hour. Since the accident trains are travelling to 50 kilometres per hour through
that region.
"[Railway accident investigations] are never considered final until all parties have weighed in
and most important of those is Transportation Safety Board of Canada. It has not released its report
yet, but we have given it our findings," said CPR spokesperson Paul Thurston. "Our finding
is the leading probable cause is a broken rail."
In fact, the Transportation Safety Board released its results of the investigation of the accident on
22 Sep 2004. It also pointed to the broken rail.
The report noted:
- The train derailed immediately south of the public crossing when the rail failed catastrophically
due to a pre-existing rail joint bolt hole crack;
- Prior to the occurrence, a corrosion pit, which had developed on the bolt hole surface, likely acted
as a stress raiser and facilitated the development of a pre-crack. The
pre-crack was not detected by ultrasonic testing one month prior to the accident;
- A cold ambient temperature induced thermal tensile stresses in the continuous welded rail and made
the rail more susceptible to brittle failure;
It also noted that the weight of impact on the wheels, "likely initiated a brittle fracture from
the root of the pre-crack through the base of the rail, facilitating the final
catastrophic rail failure."
Of the 21 derailed cars, 10 were tankers, with seven containing dangerous goods. Three of the
dangerous goods containers leaked ethylene glycol, used in anti-freeze, and styrene
monomer. Some of the chemicals leaked into a nearby marsh and into Rainy Lake.
"The post-examination of the derailed cars found there were no significant
pre-existing mechanical defects or deficiencies that may have contributed to the
accident," the report stated.
Previous inspections of the train and track did not turn up anything alarming or needing immediate
action. Prior to the derailment, the tracks were last inspected 12 Feb 2003 and wheel
impact had been checked on 2 Feb 2003.
On the one-year anniversary of the derailment in 2004, Shawanaga residents blocked each
train that passed through for 10 minutes before clearing the tracks. The action was to raise
awareness about the chemicals carried by freight trains, the speed they pass through the First
Nation and the lack of warning lights at the crossings.
Since the accident CP Rail installed another wheel impact load detector, giving a total of 10 in
Canada, formalized a cold weather slow order policy for any temperature under minus 25 Celsius where
track problems are known.
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