DARTMOUTH, N.S. — Investigators say deteriorating rail tracks are the prime suspect in a freight-car derailment that resulted in 800 people being evacuated from a downtown neighbourhood last February, a Canadian wire service reports.
Residents along Dartmouth’s shoreline had to leave their homes overnight on Feb. 15 when five CN freight cars, including a propane tanker, jumped the tracks. None of the flammable gas escaped and people returned to their homes the next day.
Eddie Belkaloul, regional manager of rail investigations for the Transportation Safety Board, said Tuesday the “marginal” condition of a track leading out of the bustling Dartmouth yard has become the focus of his agency’s investigation.
He said the distance between the rail tracks, known as the track gauge, had widened over time on the line near the densely populated neighbourhood.
“We found a problem with the track gauge . . . That gauge has to be within some parameters otherwise it (the train) is going to derail obviously.”
When wooden ties deteriorate, iron plates that hold the rails to the ties sink — a process called encaving — and the rails spread as trains pass over them. Belkaloul said it was too early in the investigation to conclude any Canadian railway standards had been violated.
“Sometimes what you have are combinations of factors . . . when you combine them together you create an unsafe condition,” he said.
The report into the Dartmouth derailment is not complete and no formal recommendations are expected for several months.
A spokesman for Canadian National confirmed that tracks had deteriorated at a rail crossing on the outskirts of the yard. Wooden beams surround the rails at the crossing, allowing cars and trucks to pass.
Pierre Leclerc, director of communications at CN, said inspectors hadn’t noticed the problem, despite twice weekly visual inspections.
“The measurements were done and everything was supposed to be okay . . . Eventually something happened and it happened underneath the thing (crossing),” said Leclerc.
CN has since replaced the tracks at the crossing and a third weekly inspection has been added, he said.
But Belkaloul said the board remains concerned about the maintenance of tracks in rail yards, particularly where there is heavy traffic of cars carrying hazardous materials near heavily populated areas.
The Dartmouth incident is similar to the derailment of three cars loaded with anhydrous ammonia in 1998 at a CN rail yard in Concord, Ont. One freight car leaked the gas used to make fertilizer, but there were no injuries and normal operations resumed within a day.
A board probe there recommended more frequent inspections by Transport Canada of tracks near rail yards.
Canadian regulations currently allow railways to do fewer checks in rail yards than they do on the main lines because trains are moving at speeds of less than 20 kilometres an hour.
Transport Canada is responsible for monitoring inspection reports by CN and the agency’s inspectors make spot checks on some parts of the railway.
Paul Hache, the inspector responsible for the Dartmouth line, said he didn’t inspect the track where the derailment took place.
“We concentrate on the main line and do inspection at random in the yards,” he said.