Severn Tunnel upgrade to bring disruption to south Wales rail services

Nation.Cymru staff

Passengers travelling between south Wales and England are being warned to expect disruption later this month as major engineering work is carried out in the Severn Tunnel.

Network Rail will close the railway between Newport and Bristol Parkway from 23 May until the morning of 9 June while engineers carry out a major overhaul of the tunnel’s overhead power system.

The work is aimed at improving the reliability of one of the busiest rail links connecting south Wales with London and south-west England.

Running beneath the Severn Estuary, the 4.35-mile tunnel is considered one of the harshest operating environments on the UK rail network because of the impact of moisture and saltwater on equipment.

Since electrification, corrosion and electrical wear have led to increased maintenance requirements and periodic disruption to services.

Network Rail said its Wales and Borders team had developed a new overhead power system specifically designed to withstand the tunnel’s conditions.

The upgrade will involve replacing 838 bridge arms supporting the overhead wires and renewing 9,000 metres of wiring throughout the tunnel.

The organisation said the system had already been successfully trialled and would now be installed across the full length of the tunnel using what it described as a “world-first” approach on this scale.

Nia Watkins, regional asset manager for Network Rail Wales and Borders, said the work was essential to the long-term future of the route.

“Running beneath the Severn Estuary, the 4.35-mile Severn Tunnel is one of the most challenging environments on the UK rail network, making this work essential to maintain safe, reliable services and support its long-term future,” she said.

“Using an innovative solution developed by our teams at Network Rail, this complex and highly coordinated upgrade is being delivered at a world-first scale across the tunnel’s full length, making the railway more resilient and reducing the risk of future disruption for passengers and freight.”

Alongside the tunnel upgrade, additional work will also be carried out around Bristol, including infrastructure improvements linked to the new Bristol Brabazon station.

Replacement buses

During the closure, replacement buses will operate between Newport and Bristol Parkway, while some long-distance services between London and south Wales will be diverted via Gloucester.

Passengers are being advised to check journeys in advance and allow extra travel time.

Great Western Railway station manager Marcus Deegan said passengers’ patience during the disruption would be appreciated.

“This investment to improve and maintain the Severn Tunnel will make a real difference to the reliability and resilience of the route for many years ahead,” he said.

The railway is scheduled to reopen fully on the morning of 9 June.