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Friday 15 Jul 2022

Scotland’s Railway gets ready for heatwave

Region & Route:

Scotland’s Railway: Scotland

With temperatures set to soar across the country early next week, Scotland’s Railway is putting plans in place to manage the hot weather and keep passengers moving.

Temperatures across Scotland may reach record levels next Monday and Tuesday, with weather warnings for extreme heat now in place across southern Scotland.

During heatwaves, rails in direct sunshine can be as much as 20°C hotter than air temperature and expand as they get warmer – sometimes causing them to curve or buckle. Metal overhead power lines can also expand in extremely hot conditions.

Network Rail engineers will carry out additional track inspections to check for heat-related problems while at some locations special remote monitoring equipment has been deployed to help spot rails which are becoming too hot.

Our engineers have also been preparing in advance – stressing sections of track (artificially stretching the rails) in known hot-spot areas to help them cope with sudden rises in temperature and painting rails white at key locations to help reflect the sun and keep them up to 10°C cooler.

Some speed restrictions will be in place on Scotland’s Railway early next week to help manage the impact of the extreme heat, but ScotRail services are expected to run as planned.

Some cross-border operators will be altering their timetables due to the significantly higher temperatures south of the border and passengers should check their journey with their operator in advance.

Liam Sumpter, Network Rail Scotland route director, said: “Our engineers will be out throughout the weekend and into next week monitoring rail temperatures and working hard to keep customers on the move.

“Heat can create real challenges for the railway, causing rails to expand and buckle, overhead lines to sag and surrounding land to dry out, making our tracks more susceptible to flooding once the weather breaks.

“We’re urging passengers to plan their journeys carefully, especially on cross-border routes as temperatures in England and Wales will be even more extreme than those we will face in Scotland.”

Scotland’s Railway’s specialist weather desk and meteorologists will also be monitoring heavy rain which is expected to reach Scotland on Tuesday night and Wednesday.

How we prevent tracks from getting too hot:

• We paint certain parts of the rail white so they absorb less heat – and expand less. Typically, a rail painted white is 5°C to 10°C cooler than one left unpainted.

• As most track is made up of long pieces of rail that are stretched and welded together, there is much less chance of buckling in very high temperatures because there is reduced compression.

• When a track is made up from short rails bolted together, we leave small gaps between each one so that expansion doesn’t cause a problem.

• We’re always improving how we measure and calculate rail temperatures. One way we’re doing this is by installing probes that alert us when track temperatures rise to give us the chance to take action and stop a problem before it happens.

• In some parts of the network, tracks are laid on reinforced concrete slabs rather than on sleepers and ballast (the bed of stones that supports the sleepers). This helps to prevent rails from buckling.