Network Rail reveal how they tackled the Severn Tunnel as they replace nearly two miles of track

Network Rail reveal how they tackled the Severn Tunnel as they replace nearly two miles of track

Network Rail engineers have shown how they’ve tackled one of the most challenging environments in rail.

The stretch of railway, from Monmouthshire in Wales and South Gloucestershire which includes the Severn Tunnel has reopened after a ten-day period of upgrades and work on the line.

Engineers installed 3.2km of new track alongside replacing over 5,000 sleepers and laying 13,000 tonnes of ballast. Over that period of work, the teams worked a collective 17,000 hours in order to complete the work within the 10-day period.

Network Rail has now revealed a video of the work showing how they carried out the work and why it was needed. The Severn Tunnel is one of the hardest environments for rail, with salt corrosion causing a real challenge and cutting the life expectancy of the rail infrastructure within the tunnel significantly.

Mark Dix, project manager at Network Rail Wales & Borders, said: “The Severn Tunnel is a vital rail link for passengers and freight between Wales and England - around 32,000 trains travel through the tunnel each year. 

“Although working in the 150-year-old-tunnel presents some unique challenges, such as water and corrosion, we are determined to continuously maintain the railway to keep trains running. 

“As always, I would like to thank passengers and operators for their patience while we safely carried out this essential work.” 

As well as the challenging environment that the engineers worked in, trains kept running with diversionary measures put in place in Gloucestershire to ensure that the works could be completed over the ten-day period rather than working across several weekends.

The main bulk of the work has been completed now with only one period of closure now scheduled on Sunday 25 June.

Image and Video credit: Network Rail

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