Build-up of floodwater caused Corby landslip that left trains stranded
Floodwater caused a cutting slope to fail on June 13 2019, stranding an East Midlands Trains High Speed Train and forcing the evacuation of its 191 passengers to another train ( RAIL 882).
An investigation by the Rail Accident Investigation Branch (RAIB) found that the cutting slope, about a mile north of Corby station, was not designed to cope with a large volume of water that had accumulated at its crest.
Two nearby flood storage ponds had overfilled with water from a brook. A blockage beneath the bridge over the brook compounded the problem by causing the brook’s level to rise, so that water flowed over a spillway and into the ponds (which had not been routinely pumped out for nearly four weeks).
At about 1553 on June 13, the 1434 St Pancras-Nottingham High Speed Train collided with debris in the cutting. It did not derail but was unable to move because the rear two vehicles had been trapped by sandy gravel washed out from the cutting slope.
Passengers were later transferred to the southbound 1359 Sheffield-St Pancras, but this was then trapped by flood water to its north and south. Once lighting and road transport were in place, the passengers were taken off the train by 2314. No passengers were injured but overcrowding made conditions on the southbound train uncomfortable.
Although flooding was the primary cause of the failure, RAIB noted that despite monitors having been fitted at the ponds to check water levels, vandalism meant that controls for pumps had been relocated to a nearby sewage pumping station. They were manually operated by a field technician employed by Anglian Water who uses his experience to decide when to run them.
Although co-operation between the railway and other bodies has historically been poor, RAIB said the situation has improved in recent years - although meetings did not result in any actions to address the flooding problem.
Five recommendations were made. The first was that the Environment Agency, Northamptonshire County Council, Anglian Water, Homes England, Corby Borough Council and Network Rail should lead the production of a timebound plan to implement and maintain an effective flood management system at Pen Green Lane.
The second is that NR should compile a list of locations on or around its infrastructure where it is known that surface water flooding with the potential to affect railway safety occurs during normal rainfall.
It should also review the adequacy of the flood management arrangements in such locations and identify the organisations responsible for each of the assets that form part of a flood management system or which could affect flood-related risk to the railway.
Network Rail should review and amend its processes for management of earthworks, and NR and the Rail Delivery Group should carry out a joint review of procedures and codes of practice for managing stranded trains and carrying out train evacuations, to identify what equipment is needed to deliver the requirements in these procedures for each method of train evacuation.
The final recommendation is that NR and train operators should: take steps to ensure the equipment identified as required for managing stranded trains is available when needed; brief and/ or train staff involved in managing or responding to train detrainments on how to get the equipment to the site of a stranded train and use it correctly; and prepare rolling stock-specific guidance.