An “insufficient” risk assessment relating to snowmelt has been blamed for a train derailment in the Highlands.
A report by the Rail Accident Investigation Branch (RAIB) concluded that Network Rail’s monitoring strategy failed to notice a landslip at Loch Eilt which led to a train derailment in January.
While no passengers or staff were injured, significant amounts of diesel leaked into a drainage channel following the incident.
The report recommended that Network Rail improves its monitoring and weather forecasting systems as a result of the accident.
It concluded that Network Rail did not “not recognise” the risk of a landslip “because the process for interpreting the forecast was insufficient”.
“Snowmelt and ground thaw risk was not appreciated because the process for interpreting the forecast was insufficient,” the RAIB report said. “Network Rail should complete its evaluation of the means by which snowmelt can be incorporated in adverse weather processes applicable to earthworks.
“It should also carry out a similar evaluation for risk due to ground thaw. If justified by these evaluations, Network Rail should include improvements in monitoring these effects for the next generation of its weather information tools, such that the true level of risk associated with such a combination of weather conditions is accounted for in its management of landslip risk.”
Network Rail said that it will now review the RAIB findings and is also conducting its own investigation.
“We spend around £20m a year on earthworks and drainage projects in Scotland to try to prevent landslips and flooding and carry out regular inspections in locations where landslips are a known risk,” a Network Rail spokesperson said.
“We’re also exploring how new technologies and monitoring systems and improved weather forecasting techniques can be used to improve how we manage weather events.”
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