Rail disruption fears after track soil shrinkage

A main rail line is expected to introduce timetable changes and reduced speeds due to the dry weather.

An announcement will be made soon affecting the South Western Railway (SWR) line between London and Exeter, BBC News understands.

The issue is soil shrinkage on rail embankments, which causes the tracks on top to buckle.

The same problem reduced services on the line from hourly to one train every two hours from August to November 2025.

The shrinkage - known as Soil Moisture Deficit (SMD) - is already running at a higher level than in 2025, according to SWR data.

SWR train driver Peter Cook said it was noticeable from his cab.

He said: "You can see it coming, you can feel it coming. You can see the rails for a good distance.

"You can tell when rails are moving and you can see that from a long line away. And at greater speeds it's more exaggerated."

Anne Browne, from SWR and Network Rail, said SMD problems were becoming more regular.

She added: "We're now seeing it happening almost every year.

"If anything, we're slightly worse than where we were last year. I think it is just a sign of climate change."

Browne said SWR was working with the University of Southampton on potential long-term solutions, which could involve changes to track materials or embankment vegetation.

The West of England line, which connects London with parts of Devon, Dorset, Hampshire, Somerset and Wiltshire, was "particularly vulnerable" to SMD, according to the rail operator.

The line includes single-track sections with passing loops, meaning that delayed trains can have a knock-on effect on other services.

It can take weeks or even months for soil moisture levels to return to normal, SWR said.

Timetable changes due to SMD have already been announced on routes through part of East Anglia from Monday.