ATSB released its report into the derailment of freight train 7AD1 at the Edith River rail bridge near Katherine in the Northern Territory on 27 December 2011. The derailment caused significant damage to the bridge and the rolling stock. A number of wagons derailed into the Edith River. The driver was uninjured but the co-driver suffered back injuries. The ATSB found that the derailment was caused by the wash-away of the south eastern embankment, associated sub-grade and ballast on the approach side of the rail bridge. The extent of the wash-away meant that the track could not support the weight of the train and it collapsed. The wash-away resulted from a severe flood event caused by torrential rain in the aftermath of cyclone 'Grant'. The safety message from this event is that it is essential for rail network operators to have robust systems in place to monitor and mitigate the risk of severe weather events and ensure that the safety of railway operations is not compromised.