Services on the West of England line between Salisbury and Exeter are being restored from November 15, following months of disruption.
Clay embankments had shrunk during the driest summer since 1936, causing tracks to become uneven (RAIL 965).
Network Rail imposed a speed restriction of 40mph between Tisbury and Gillingham in August. A further speed restriction was in place near Axminster.
NR said that repairs were futile until the shrinking stopped in late October, until rainfall returned to normal levels and the embankment stabilised sufficiently for the track to be realigned.
It meant that South Western Railway’s Class 159 diesels could only run at half the normal speed along much of the route.
And because this is a busy single-track line with limited passing places, each slow train also forced every service in the opposite direction to run late as well.
SWR’s solution was to reduce Exeter to just a two-hourly service, with one train an hour to Yeovil.
The Salisbury to Exeter Rail Users Group (SERUG) said it reduced the average speed on the long-distance route to only 32mph.
There are 6,000 clay embankments in the Southern region of Network Rail, extending to around 600 miles. The four-mile section near Tisbury is among the longest.
In August, Network Rail told RAIL that a permanent fix to make the region resilient to climate change would cost between £15 billion and £20bn and take decades. It said the number was so large, it could never happen.
The return to full service from November 15 will be brief. A further week-long engineering blockade of the line is due on December 10-18, when services between Salisbury and Exeter will be diverted via Westbury.
To read the full story, see RAIL 970.
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