It’s nearly officially Autumn which for many people means a return to darker evenings, cosy knitwear, candles and hot chocolate. But for those who manage railway networks, each Autumn brings with it a challenge: Leaves on the line.

Though mocked by passengers and seen as an excuse, rather than a justification, for train delays, leaves falling onto the track really are problematic. The main reason being is that they change the interaction between the train’s steel wheels and the steel rail it runs on. Indeed, there are over 13 million trees on and next to the UK’s railway and every Autumn, thousands of tonnes of leaves fall onto the tracks each season.

Heavy leaf fall can also happen within hours when windy & wet conditions prevail.  The rain mixing with the leaves means they are more likely to stick to the train rails.  The rolling action and weight of passing train wheels compresses the leaves even further and leaves a greasy mulch covering the top of the rail.  This mulch is like the black ice you find on the roads.  Consequently, a compaction of leaves lowers rail adhesion between the train wheels and the rails.  So, train drivers have to pull out of stations more slowly and brake much earlier for stations and signals.  This can lead to longer journey times and train delays for some passengers.

When there is a build up of leaves on the track they can also cause a barrier to form between the train wheels and the electrical parts of the track (parts of the track which helps Network Rail to pin point the location of trains.) When a train can not be pin-pointed the trains behind will be delayed at red signals until the first train’s location is known.  This way the teams that operate the rail control rooms can be confident that there is always as safe distance between trains.

Leaf Busting Trains

Did you know that Network Rail have 67 leaf-busting trains which move around the UK’s railways which clean away the leaves and debris by using a high-pressured water jet. These leaf busting trains also apply a gel which contains a mix of sand and steel grains, to help the train wheels to run along the tracks as they normally would do. They also have numerous leaf busting teams on hand 24/7 at key locations across the UK who scrub the top of the rails by hand with a sand-based treatment, so that trains can safely run on the tracks.

Network Rail to Invest in Latest Laser Technology

Not happy with leaf busting trains Network Rail is set to test the LPS Lasertrain technology which is designed to clear the residue of fallen leaves from train lines at speeds up to 60mph. It will be trialled on stretches of the East Lancashire railway in the northwest of England this October, as part of a UK-wide initiative to bring new technology onto the railways to make them cleaner, greener and safer.

LPS CEO, Harm Medendorp said: ‘’ We are very excited Network Rail has chosen our technology for future consideration, and to have the opportunity to showcase how our smart and sustainable rail cleaning solution can create a more reliable and efficient service for UK passengers during the tough Autumn months. Leveraging the power of laser light, we have increased our cleaning speed from 25mph to 60mph ‘’