Major bridge work starts this weekend as M4 upgrade hits halfway point
The M4 smart motorway upgrade hits its halfway point this weekend with one of its most complex pieces of engineering to date.
The Thames Bray Bridge, which carries the motorway over the River Thames west of London is being widened to fit an extra lane in each direction. It is part of a project to improve journeys by adding vital extra capacity on the M4 between London and Reading, and is the most challenging aspects of the ground-breaking project to date.
Using weekend closures of the M4, huge steel beams, which will form the deck of the widened bridge, will be lifted into place. The beams have been prefabricated into three sections, weighing nearly 300 tonnes, so they can be installed while keeping the time that the road need to be closed for to an absolute minimum.
Creating extra lanes on the M4 requires replacing 11 bridges over the M4 to they are wide enough to fit the improved motorway. Work on this task is well underway. The Thames Bray bridge differs in that it carries the motorway itself over the River Thames, and work has been carefully designed to keep the M4 open to traffic wherever possible. It is one of the most complex pieces of work involved in the upgrade of the M4 to a smart motorway, which is being carried out by a Balfour Beatty VINCI joint venture on behalf of Highways England.
To complete the work, the M4 will be closed in both directions between junction 6 (at Slough) and junction 8/9 (for High Wycombe) over the next two weekends:
- From 8pm Friday 29 May to 6am on Monday 1 June 2020
- From 8pm Friday 5 June to 6am on Monday 8 June 2020
During the closures, motorway traffic will be diverted via the A308M, A308 and the A355 and there will be fully signed diversions in place. However, as delays are expected drivers are advised to plan ahead, leave extra time for their journeys and consider alternative routes if possible.
The size of the beams and the cranes required to lift and position them will also involve stopping navigation on the River Thames between Boveney and Bray locks during these weekends. The Environment Agency will issue a Harbour Master’s Notice for this stoppage.
The towpath which is part of the Thames Path National Trail will also be closed during these weekends with a signed diversion along local footpaths, minor roads and via the Jubilee River to enable walkers to re-join the route past the works.
The Thames Bridge at Bray opened in 1961 and carries the M4 over the River Thames between junctions 7 and 8/9. To accommodate the new 4-lane smart motorway, the bridge requires an 8-metre extension on the north side of the bridge. This will be in the same style as the existing structure and will be complete and open for use in 2021. The smart motorway upgrade is expected to be open for traffic in 2022.
Traffic volumes on the M4 have significantly reduced as people follow Government advice to stay at home to stop the spread of Coronavirus. Anyone making an essential journey who will be affected by the closure should leave extra time for their journeys and consider alternative routes if possible.
Roadworks affect all journeys which is why it is important they are completed as quickly as possible.
Their roads remain open and they will continue to maintain the network, ensuring that life-saving medicine, equipment, supplies and healthcare staff can travel to where they are needed most
All their sites have strict safeguarding measures to ensure the health of their workforce and prevent the spread of Covid-19 and none of their sites are open to the public.
The work is part of a project to upgrade the M4 between junctions 3 and 12 to a smart motorway. For more information and to sign up for project newsletters please visit: https://highwaysengland.co.uk/projects/m4-junctions-3-12-smart-motorway/
Highways England provides live traffic information via its website (www.highwaysengland.co.uk/traffic), local and national radio travel bulletins, electronic road signs and mobile apps. Local Twitter services are also available at @HighwaysSEAST.