Network Rail is preparing its 61-strong fleet of Railhead Treatment Trains (RHTT) and Multi-Purpose Vehicles (MPV) to minimise the impact of leaves on the line this autumn, ahead of the beginning of leaf fall season on Monday 1 October.
Leaves on the line – an annual cause of delays for rail passengers – pose problems for the railway when the leaves stick to damp rails and passing trains compress them into a thin, black layer on the rail which – much like black ice on the roads – can affect train braking and acceleration. This means that train drivers have to slow down earlier for stations and signals to avoid overshooting them. They must also accelerate more gently to avoid wheel spin. All this can increase journey time and leads to delays for passengers.
Build-up of leaf mulch can also make it harder for our signallers to detect a train’s location, causing delays when subsequent trains are not able to proceed until the train in front is further up the line.
Equipped with a high-pressure pump, our leaf-busting trains clean the railheads with adhesion modifier – a mixture of suspension gel, sand and steel or iron shot – that is pushed through the compressed leaves and debris, clearing the tracks and helping the signalling system to work correctly.
Network Rail's autumn preparation programme includes a number of measures:
• A total of 61 leaf-busting trains (32 MPVs and 29 RHTTs) which move around the network cleaning the top of the rail by spraying it with a water jet at very high pressure (1500 bar) to blast away leaf mulch
• These trains also lay adhesion modifier, a composite material of sand and steel shot suspended in a gel-like substance, which is applied to the rail to aid traction
• We have ‘leaf-busting’ teams available 24/7 at key locations to scrub the top of the rails by hand with a sand-based treatment
• Management and replacement of lineside vegetation with species less likely to shed leaves on to the tracks
• Between 1 October and 13 December, Network Rail receives adhesion forecasts twice a day from a specialist weather forecaster which highlight locations requiring action. This allows resources to be planned more effectively
• As an industry, we work together to run a safe and reliable service. In areas with heavy leaf-fall some train operators publish special autumn timetables with revised journey timings to allow train drivers to drive more cautiously than at other times of year.
Andy Thomas, Network Rail’s managing director, strategic operations, said: “Every autumn, even with the best preparation, leaves fall onto the line, which can cause the same conditions as black ice on the roads. With millions of trees growing alongside the railway, it’s something the rail industry takes seriously. That’s why our ‘leaf-busting’ trains and front-line teams are out there 24 hours a day, seven days a week, to make sure we can get passengers from A to B safely and reliably.