M48 Severn Bridge: Upcoming resurfacing trial – Saturday 01 August until Sunday 27 September 2026
From National Highways:
The original bridge design and construction in the 1960s featured a 35mm surface that was laid by hand. This was replaced between 1989 and 1991 with the same thickness of material.
Any new surfacing needs to be laid at the same thickness of just 35mm, compared to 40mm+ on more modern bridge structures. This is to ensure the weight across the structure is not increased above that for which it was designed.
As part of the long-term maintenance of the bridge, we’re trialing resurfacing a 200-metre section of the bridge westbound to ensure that the new road surfacing can be laid thin enough using a machine.
Once the trial surface has been laid, regular inspections will take place to ensure the surface remains in sound condition. If the trial is successful, we’ll be fully resurfacing both carriageways in 2027 / 2028.
How we’ll be working
We know the bridges are a key economic link between England and Wales.
We’re doing all we can to keep disruption to a minimum. We’ll be working over the summer period as this is primarily a commuter route and the quietest time of the year for traffic on the bridge.
To enable our teams to work safely, we’ll be installing a temporary contraflow system on the Severn Bridge.
When the contraflow is operational, there will be a single narrow lane running in each direction on the eastbound carriageway. There will also be a 30mph limit and average speed cameras.
Access will be maintained throughout to Chepstow.
Upcoming closures
We’ll be working from Saturday 01 August until Sunday 27 September 2026 for the resurfacing trial.
Contraflow will be in place from 8pm Saturday 08 August until 8pm Friday 18 September 2026.
To set up the contraflow, there will be a mixture of overnight closures, lane closures and 24hour weekend closures.
During full closures, well signed diversion routes will be in place via the M4 Prince of Wales Bridge.
Closures
Saturday 01 August – (8pm – 6am)
- Full overnight closure of westbound carriageway and lane 2 closure eastbound.
- Westbound diversion via M4 Prince of Wales Bridge.
Sunday 02 August – (6am – 8pm)
- Daytime westbound lane 2 closure. 30mph limit in place.
- Full overnight closure of eastbound carriageway and lane 2 closure westbound.
- Eastbound diversion via M4 Prince of Wales Bridge.
Monday 03 August – Thursday 06 August – (6am – 8pm)
- Daytime eastbound and westbound lane 2 closure. 30mph limit in place.
- Full overnight closure of westbound carriageway and lane 2 closure eastbound.
- Westbound diversion via M4 Prince of Wales Bridge.
Friday 07 August (daytime) – (6am – 8pm)
- Daytime eastbound and westbound lane 2 closure.
- 30mph limit in place.
From 8pm Friday 07 August until 8pm Saturday 08 August – inclusive 24/7
- Closure of westbound and eastbound carriageways.
- Diversion via M4 Prince of Wales Bridge.
Contraflow
From 8pm Saturday 08 August until 8pm Friday 18 September – contraflow in operation
- There will be a single narrow 3m wide lane running in each direction on the eastbound carriageway.
- We’ll be working on the westbound carriageway.
- There will be a 30mph limit in place and average speed cameras.
- In addition, the footpath on the westbound side will be closed.
- The footpath on the eastbound side will remain open.
Closures
From 8pm Friday 18 September until 8pm Saturday 19 September – inclusive 24/7
- Closure of westbound and eastbound carriageways.
- Diversion via M4 Prince of Wales Bridge.
Saturday 19 September (8pm – 6am)
- Overnight eastbound and westbound lane 2 closure.
- 30mph limit in place.
Sunday 20 September – Thursday 24 September (6am – 8pm)
- Daytime eastbound and westbound lane 2 closure.
- 30mph limit in place.
- Full overnight closure of westbound carriageway and lane 2 closure eastbound.
- Westbound diversion via M4 Prince of Wales Bridge.
Friday 25 September (midnight – 8pm)
- Eastbound
