The Australian Transport Safety Bureau has found that the Australian Rail Track Corporation’s risk control processes were ineffective in the lead-up to a derailment in South Australia midway through last year.
Early in the morning of April 10, 2014, SCT Logistics train 3MP9 derailed after travelling over track that had been undercut by floodwaters near a culvert between Tarcoola and Malbooma, SA.
Around 300 metres behind the lead loco, 18 wagons derailed, with eight rolling onto their sides.
There were no injuries to the crew or bystanders, but there was significant damage to the track, rolling stock and freight goods, according to the bureau.
What the ATSB found during its investigation launched shortly after the incident, was that floodwaters caused scouring of the track formation, compromising its capacity to support the train.
The ATSB determined that runoff from the heavy rain that had fallen in the catchment area adjacent to Malbooma on April 9, 2014, caused a flash flood event.
“The volume of floodwater exceeded the capacity of a double drainage culvert designed for a 1:50 year average flood recurrence interval,” the ATSB said in its report, released yesterday.
“This resulted in water overtopping the track formation with ballast and sub-grade scouring on the south side of the track.”
As a result of the scouring, the track couldn’t support the train in certain areas. The resulting deformation caused the derailment, according to the bureau.
Role of the ARTC
According to the report, Australian Rail Track Corporation (ARTC) risk control processes were ineffective in developing and implementing changes to operational procedures from the findings of previous incident investigations.
“The ARTC did not have a comprehensive system in place to identify and actively manage the risks to their network from severe weather events, and had not established a register for recording ‘special locations’ for the management of track infrastructure prone to flooding,” the bureau found.
There were no anomalies found with the operation of the train or the condition of rolling stock before the derailment.
As a result of the investigation, the ARTC has implemented Operational Procedure OPP-01-05 ‘Monitoring and Responding to Extreme Weather Events in the East-West Corridor’ and has purchased and installed remote weather monitoring and recording stations at Barton, Cook, Rawlinna and Zanthus, according to the ATSB.
Automated alerts will be provided by the weather stations, which will be linked to the Early Warning Network.
The ARTC has also installed four water flow monitors at culverts identified through a hydrology study of the Trans Australia Railway. Field evaluation of this equipment is currently being undertaken.
The ARTC is also optimising its inspection and maintenance activities with upgrades to its electronic asset management system underway. This process will include the recording of ‘special locations’ affected by severe weather events.
“To ensure that the safety of rail operations is not compromised during severe weather events, it is essential that rail transport operators have robust and responsive systems in place to actively monitor and manage the foreseeable risks,” the safety bureau concluded.