SIGNIFICANT DELAYS were caused to trains between Crewe and Shrewsbury in early December 2017 as a result of modular signalling equipment being confused by snow. Network Rail does not intend to modify the equipment, which it says was functioning correctly.

The Crewe to Shrewsbury line was one of Network Rail’s pilot modular signalling installations, controlled from the Wales Railway Operating Centre in Cardiff. Level crossings were converted to a new type, Manually Controlled Barriers with Obstacle Detectors (MCB-OD), enabling the barriers to descend and rise automatically except if an obstacle is detected on the road. Teething troubles with the technology delayed commissioning, which had been planned for January 2012.

During and after snowfall on 8 December 2017 and the following days, crossing barriers frequently did not descend as required because the equipment detected snow as an obstacle. Many passenger services lost time, typically 10 to 30 minutes.

Explaining the situation in mid-December, a spokeswoman for Network Rail’s Wales Route said: ‘Obstacle detection technology plays an important part in improving the safety of level crossings across Wales and Borders. We have recently fitted hoods on to these detectors to protect them from dirt and debris. However, heavy snowfall last week built up on the obstacle detectors between Crewe and Shrewsbury and we were unable to deal with this issue as quickly as usual, due to many of the roads in the area being closed or impassable because of the extreme weather.

‘There is a written procedure for train drivers and signallers to follow when there is an obstacle on the level crossing, and an on-site operator with direct view of the crossing can allow signalled moves to take place if the crossing is safe for trains to pass.’ The crossings are fitted with closed circuit television cameras. Rhodri Clark

Winter wonderland: unit No 175011 at Wistanstow on the North & West route on a snowy 12 December 2017.;
Landfox Photography