Fact or friction? Issues with leaves on the railway lines

Leaves on the railway lines supposedly costs the UK millions of pounds each year in delays, but how does something so small impact something so large?

The worst weather for causing train delays in autumn is in fact damp weather. As leaves begin to drop off the trees, turbulence of passing trains causes them to get sucked onto the lines.

Strong or brisk winds also play a crucial role in encouraging large leaf fall in short periods of time. When inclement weather then follows a period of windy weather, this causes the leaves to stick to the railway lines.

The leaves then deposit a sap residue on the lines as the heavy train wheels pass over them, causing the tracks to become very slippery. Consequently, breaking becomes more difficult, along with insufficient traction. A build up of leaves can also cause a loss of track circuit detection.

Many trains end up missing the exact spot at a location they should stop at, termed technically as "station overruns". Network Rail say that "leaves on the line are the rail equivalent of black ice on the roads".

To combat the issue, rail companies use special "Railhead Treatment Trains" that release high-pressured water jets to blast away the leaves, in addition to a gel solution, containing a mix of sand and steel grains, to help them run as usual.

Railway companies often implement different schedules for autumn, enabling extra time for drivers to get their passengers to their destination safely. Keep track of whether the weather will delay your day, via the WeatherRadar.