FROM 27 May, new weight restrictions will come into force on the M48 Severn Bridge, limiting access for larger heavy-goods vehicles.
National Highways has announced that lorries over 7.5 tonnes will no longer be able to use the historic crossing, with larger vehicles instead being diverted to the newer M4 Prince of Wales Bridge. The measure follows inspections that revealed wear and tear on the bridge’s main support cables.
Chris Pope, Programme Delivery Manager at National Highways, said the restrictions are a precaution aimed at preserving the bridge for future use. “The bridge is still safe, but it wasn’t built to carry the volume and weight of today’s traffic,” he said.
Heavy vehicles have grown larger over the decades, and with traffic levels also significantly higher than when the bridge opened nearly 60 years ago, engineers are concerned that continued strain could eventually lead to a full closure.
National Highways estimates that the new limit will divert about 10% of current traffic, mostly HGVs, to the M4 crossing. Emergency services, buses, coaches, gritters, and recovery vehicles will still be allowed to use the M48.
In 2024, the bridge carried around 32,000 vehicles daily, including more than 3,000 HGVs. The restriction is expected to stay in place for between 12 and 18 months while long-term solutions are considered.
If the M4 Prince of Wales Bridge were to close unexpectedly, HGVs over the weight limit would be directed via the M5 and M50.
To help enforce the restriction, National Highways is also considering the use of Automatic Number Plate Recognition (ANPR) technology.
