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The Project Control Framework
This framework sets out how we, together with the Department for Transport, manage and deliver major road improvement projects.
A404(M) Western Region Railway Bridge Replacement
A404(M) Western Region Railway Bridge Replacement
Where was the project located?
The scheme replaced the Western Region Railway Bridge, which carried the A404(M) over the mainline railway line between London and the West of England, between junctions 9a and 9b near Maidenhead, Berkshire.
The A404(M) carries over 50,000 vehicles every day, and the four line railway below it is a key passenger and freight route with up to 30 movements every hour.
Why was the scheme needed?
The Western Region Railway Bridge was in a deteriorating condition and required complete replacement.
The steel used in the previous bridge's construction, which dated from the 1930s, was of poor quality, and the water draining from the road, including the salt that is used to treat the road during cold periods, built up around the bridge supports. Over time, this had a corrosive effect.
What work was carried out?
The project has involved the complete demolition and replacement of the entire structure, while balancing the needs of road users, rail users and people living nearby.
The old bridge was taken down and the new bridge constructed in phases. First we demolished then rebuilt the southern side of the bridge. We then rebuilt the centre section, and lastly we demolished and rebuilt the northern side of the bridge. The sections of the new bridge were slid together, into their final positions.
We have also upgraded the noise barriers along the road and the bridge itself, as well as resurfacing the main A404(M) carriageway, on both directions across, the railway bridge.
The new bridge will have a life expectancy of 120 years.
How did this benefit road users?
We have been able to keep two lanes on the A404(M) in each direction open to traffic at virtually all times throughout the work. Each phase involved some major civil engineering work, and, for this, temporary closures of the A404(M) were required. The work could not be safely completed with traffic running nearby. We planned most closures to occur at weekends, when the traffic flow is lowest.
How do I find out more information?
If you have any queries about this project you should contact the Highways Agency Information Line by emailing ha_info@highways.gsi.gov.uk or calling 0300 123 5000.
Road User Satisfaction Survey
The Highways Agency would like to thank you for your cooperation and patience during the major road works on the A404(M). In order to improve our service to customers, we would appreciate it if you could take five minutes to follow the link below and complete the survey:
