A new weight restriction is set to come into force on the M48 Severn Bridge from 27 May, following inspections that revealed deterioration in the structure’s suspension cables. National Highways has announced that vehicles over 7.5 tonnes will be banned from using the bridge for safety reasons, with the measures expected to remain in place for up to 18 months.

While emergency services, buses, coaches, gritters, and recovery vehicles will be exempt, most HGVs will be diverted to the M4 Prince of Wales Bridge. This move affects around 10% of the bridge’s daily traffic – around 3,270 heavy vehicles. National Highways said the bridge remains safe but wasn’t built to handle the weight and volume of modern traffic.

Local councillors have voiced concern about the impact on businesses and communities. Councillor Lisa Dymock said firms in her ward that rely on the M48 face rising costs and logistical challenges. Delays caused by ongoing M4 roadworks and potential diversion routes of up to 95 miles are also fuelling worries.

National Highways is now working with hauliers and stakeholders to manage the changes. The recent cable assessments, finalised in late 2024, confirmed significant deterioration in cable strength, prompting the precautionary restrictions.