Report on railway asset failures due to flooding and scour

Zora van Leeuwen has completed a summer placement with JBA Trust to investigate and document railway asset failures due to flooding and scour between 2003 and 2013.

In the report, asset failure is defined as “complete or partial collapse of the structure sufficient to cause derailment or closure of the line”.  The most common failure mechanism was found to be the undermining of abutments or piers by scour, resulting in their collapse.

For the four incidents with sufficient data for a flood and/or rainfall frequency estimate to be carried out, three of the failures happened during relatively minor flood events. Only one of the bridge failure events was caused by a rare or exceptionally rare flood event. Extenuating circumstances, such as the build up of debris, exacerbated the effects of scour leading to the failure of structures in relatively minor flood events.  These factors, rather than the flood events alone, have caused three of the four failures.  The report recommends that further work should be carried out investigating these factors.

The full report will be made available as an educational and research resource.  Please get in touch if you are interested in using this resource.