Travel warning as Severn bridge and tunnel to shut

An overhead shot of the two crossings over the River Severn
Commuters and tourists are warned as the busiest routes between Wales and England close for upgrade work [MJRichardson | Geograph]

Travellers on the busiest routes between Wales and England will face disruption from Wednesday as both the M4 Severn Bridge and Severn rail tunnel will close for repairs.

Trains between south Wales and Bristol, London and England's south coast will be affected by the Severn Tunnel's 16-day closure from Wednesday until 19 July.

Drivers are warned the M4's Prince of Wales Bridge will be shut in one direction for five nights in July, starting from 15 July.

People are told to use the original M48 Severn Bridge as the diversion route when the M4 crossing is closed.

When is the Severn Bridge shut in July?

A picture of the second Severn Bridge at night
Latest traffic data suggests about 75,000 vehicles use the M4 Prince of Wales bridge over the River Severn every day [Getty Images]

Highways England, which maintains the two Severn bridges, warned commuters and tourists they will face delays until autumn as there will be a two-lane contraflow on the bridge so workers can do resurfacing work.

It means on occasions in July, the only main route between south Wales and the south west of England will be over the M48 bridge linking Chepstow and Aust.

  • On Monday 15 and Tuesday 16 July, the M4's westbound carriageway will be shut and eastbound reduced to one lane between 22:00 BST and 06:00 the following mornings.

  • On Wednesday 17 and Thursday 18 July, the M4's eastbound carriageway will be shut between 21:00 and 06:00 the following morning.

  • On Saturday 20 July, the M4's westbound carriageway will be shut between 22:00 and 06:00 the following morning.

  • On Saturday 27 July, the M4's westbound carriageway will be shut between 22:00 and 06:00.

  • From 06:00 on Sunday 28 July, a reduced speed limit and a two-lane contraflow will be enforced on the M4 bridge and continue throughout the summer.

Why is the Severn Bridge shutting?

Highways England said it would also need more overnight closures of the M4 bridge later in summer and autumn as road resurfacing progresses.

"If using the bridge this summer, please expect delays and be prepared to use the M48 to help ease congestion," said the road agency.

"Doing this work in the summer reduces the risk of the M48 bridge being closed due to weather, providing an alternative route for anyone crossing the river."

The English entrance to the Severn Tunnel
About 200 trains a day use the four-mile (7km) Severn Tunnel between south Gloucestershire and Monmouthshire [BBC]

It comes as train passengers between south wales and England face more than two weeks of disruption with the Severn Tunnel closure between Wednesday 3 July and Tuesday 19 July.

It means travellers on mainline trains between south Wales and London face at least an hour extra on their journey as the service will go via Gloucester and not stop in Bristol.

Network Rail has also warned there will be a limited rail replacement service running between Newport, Severn Tunnel Junction and Bristol Parkway - with none running direct to Bristol Temple Meads.

Map of diversions while the Severn Tunnel is shut
The rail replacement services between south Wales and England while the tunnel is shut [Network Rail]

Why is the Severn Tunnel shut?

Engineers positioning new track laid in the Severn Tunnel
Salt water makes the environment inside the Severn Tunnel more corrosive so track has be replaced more often [Network Rail]

Engineers will replace four miles (7km) of track – the entire length of the south Wales-bound side – by installing 66 new rails.

The team will also install 10,800 sleepers and more than 22,000 tonnes of new ballast and remove 21,000 tonnes of spoil.

Workers will also replace some 900m (2,950ft) of track at Cattybrook near Almondsbury and more than 230m (750ft) of track drainage will be replaced at Patchway Gap – between the two Patchway tunnels near Bristol.

The Severn Tunnel will also be closed for follow-up work on the weekends of 27 and 28 July and 24 and 25 August.

What major events will be affected

Shania Twain performing on stage on her current tour
Grammy-award winning singer Shania Twain will play Chepstow after her legends slot at Glastonbury [Getty Images]

Music fans attending big outdoor concerts in south Wales this July could be affected getting to and from those shows and have been warned to plan ahead and leave additional time for their journeys.

Shania Twain, Sir Tom Jones and Hozier are booked at Chepstow Racecourse on 5 July, 6 July and 9 July respectively while the Severn Tunnel is shut.

The National, Manic Street Preachers, Suede, JLS, Idles, Noel Gallagher, Madness and Rick Astley are also set to play Cardiff Castle when the tunnel is closed.