News

Severn Bridge traffic restrictions to last six weeks for resurfacing trial

23 Jul 2026 3 minute read

Looking down at and across part of the M48 Severn Bridge. Picture: National Highways

Nation.Cymru staff

Motorists using the Severn Bridge will face six weeks of traffic restrictions next month as engineers carry out a trial that could pave the way for full resurfacing of the landmark crossing.

National Highways will test a new method of laying road surfacing on a 200-metre section of the westbound M48 Severn Bridge between 1 August and 27 September.

The work is needed because the bridge’s original 1960s design only allows for a 35mm-thick road surface – thinner than those used on more modern bridges – to avoid adding extra weight to the structure.

If the trial proves successful, both carriageways of the bridge are expected to be fully resurfaced in 2027 and 2028.

To allow the work to take place safely, a temporary contraflow system will operate between 8pm on Saturday 8 August and 8pm on Friday 18 September.

During that period, a single narrow lane will run in each direction on the eastbound carriageway while work is carried out on the westbound side. A 30mph speed limit and average speed cameras will also be in force.

Access to Chepstow will be maintained throughout the works.

The project will also require several full closures of the bridge, with traffic diverted via the M4 Prince of Wales Bridge.

The first overnight closure of the westbound carriageway will take place on Saturday 1 August, followed by a series of overnight lane and carriageway closures during the following week.

A full closure in both directions will then be in place from 8pm on Friday 7 August until 8pm on Saturday 8 August while the contraflow is installed.

A second 24-hour closure in both directions is scheduled from 8pm on Friday 18 September until 8pm on Saturday 19 September to remove the contraflow before further overnight works continue until the end of September.

School holidays

National Highways said it had scheduled the work over the summer because the M48 bridge is primarily used by commuters and traffic levels are generally lower during the school holidays.

The organisation acknowledged the disruption the closures would cause but said the narrow width of the bridge meant it had to be closed more frequently than other motorways to allow maintenance to be carried out safely.

Some of the work will not be visible to drivers because it involves repairs beneath the road surface or waiting for construction materials to cure before work can continue.

Pedestrians will still be able to cross the bridge throughout most of the project using the eastbound footway, although the westbound footpath will be closed while the contraflow is in operation.

Support our Nation today

For the price of a cup of coffee a month you can help us create an independent, not-for-profit, national news service for the people of Wales, by the people of Wales.