National Highways plans to invest more than £50m into maintenance of the M5 St George's Bridge in North Somerset - including works that will see the bridge lifted 72 times to replace bearings.
The funding is part of the £8.4bn for resurfacing carriageways and renewing bridges between 2026 and 2031, included in the five-year Road Investment Strategy.
With plans for ‘extensive and essential repairs', National Highways plans to lift the structure 72 times to replace bearings underneath the bridge.
It has started work on concrete repairs to strengthen the foundations of the bridge and will also install new bridge sections and parapets, as well as making resurfacing and drainage improvements.
The work is planned to take place while three lanes are kept open in each direction, with trains also continuing to run on the lower section of the bridge.
A contraflow system is set for later this year, along with a 50mph temporary limit, which is expected to remain in place ‘throughout the length of the main works' from autumn 2026 until late 2029.
Terry Robinson, engineering lead for National Highways, said: ‘Many of the motorways and major A roads we manage were built around 60 years ago and need renewing to ensure they remain fit for purpose for generations to come.
‘The St Georges bridge is very heavily used and is now in need of significant work, which is vital to keep drivers safe and the route running into the future.
‘We appreciate this complex scheme may cause some delays in the area and we're advising road users to allow extra time for journeys, especially during peak hours.'
National Highways also plans to improve the northbound entry slip road by adding a second merge lane onto the M5 to help reduce congestion.
The next phase of works is expected to kick off early next month and will see void infilling under lanes and some overnight closures, followed by overbridge joint replacements.
