PASSENGERS travelling between South Wales and Bristol are advised to check before they travel as Network Rail carries out a significant upgrade to the Severn Tunnel.

Plan ahead this May half-term as the Severn Tunnel closes for major upgrade and Bristol Parkway or Filton Abbey Wood will be closed from Saturday, May 23, until the morning of Tuesday, June 9.

Replacement bus services will run between Newport and Bristol Parkway throughout the closure. Some trains will operate between London and South Wales via Gloucester, except on Sunday, May 24.

A limited service will run between London Paddington and Bristol Parkway, otherwise customers should travel via Bristol Temple Meads.

On Sunday May 24, services will operate only between London Paddington and Bristol Parkway, and between Newport and Swansea or Carmarthen. Train services between South Wales and Bristol will also be affected until midday on Sunday June 14.

Passengers are advised to check their journey at GWR.com before travelling and allow extra time.

The Severn Tunnel runs beneath the Severn Estuary and is one of the toughest environments on the rail network.

Moisture and saltwater have accelerated wear on the overhead power system since electrification, leading to more frequent maintenance and a greater risk of disruption.

Network Rail's engineers have developed an innovative new system, being installed at this scale for the first time in the world, that will significantly reduce corrosion, cut the need for routine maintenance and deliver a more resilient, reliable service for passengers and freight and make the route more reliable for years to come.

The work also includes track and infrastructure upgrades in the Bristol and Patchway areas, paving the way for train services to the new Bristol Brabazon station, due to open later this year, bringing passengers to the Henbury line for the first time since 1964.

GWR's station manager at Bristol Parkway, Marcus Deegan, said: “We know that bus replacement services are a significant ask of passengers, and we're genuinely grateful for their patience while this vital work is completed.

“The most important thing anyone can do right now is check their journey in advance at GWR.com and allow a little extra time. Our team at Bristol Parkway will be on hand to help.

“This investment will make a real difference to the reliability of this route for many years ahead, and the wider work will also allow us to introduce services to Bristol Brabazon later this year, reconnecting communities to rail and providing a real economic boost to the area.”

Network Rail Wales and Borders route regional asset manager, Nia Watkins, added: “We recognise this work requires the temporary closure of the railway between Newport and Bristol Parkway, and we’re grateful to passengers and local communities for their patience while we carry out these important upgrades.”

As part of GWR's Growing Places research, stations across the South West are projected to contribute £14 billion pounds in economic value and 238,000 of new jobs by 2036.

Visit GWR.com for the latest travel information and journey planning tools.