Dating from the 12th Century, Newbridge is arguably the oldest original bridge in Oxfordshire, and yet despite having no significant modifications since its construction around 750 years ago, is still carrying A415 traffic across the River Thames today. Newbridge's multi-span Gothic arch construction cannot be very precisely modelled, but using accepted assessment techniques has been found to be theoretically weak and so is now being closely monitored and is currently protected by a structural weight limit of 18 Tonnes GVW (gross vehicle weight).
In managing the steadily increasing risk that this slowly deteriorating ancient bridge will pose, we have now reached the conclusion that Newbridge can no longer be relied on to carry unrestricted A415 vehicular traffic safely in the medium and long term in its current form. As Newbridge is a Scheduled Ancient Monument though, it benefits from statutory protection designed to protect its historic importance and so cannot be replaced, reconstructed or even easily strengthened unless absolutely necessary.
Oxfordshire County Council is Newbridge's owner and is also the Highway Authority, and as such we have a statutory duty not only to preserve this Ancient Monument's historic value, but also must ensure the safety of the road user. The weight restriction and an increased inspection regime is only an interim measure, we really need to find a satisfactory long-term solution.
We are undertaking a range of work to help us identify the best long term solution for Newbridge. This includes:
- monitoring Newbridge's condition to confirm it remains safe to use, on the understanding that the current weight limit could be lowered still further if significant further deterioration occurs
- looking in more detail at the assessment methods and bridge data used, and into whether there are any acceptable strengthening methods available
- undertaking a study of all River Thames crossings west of Oxford to determine whether the A415 is the most appropriate route corridor to improve
- looking into the feasibility of building a completely new crossing of the Thames in the vicinity that would allow A415 traffic to be permanently removed from Newbridge.
- looking into the mitigation required along the A415 route if a new A415 Thames crossing was constructed that caused detrimental effects elsewhere on the route.
Our completed reports/documents can be found on the pages below:
A study to establish the feasibility of strengthening the existing bridge at Newbridge and to assess the implications of strengthening this historic structure.
An assessment of all six bridges west of the A34, and their impact on traffic over the Newbridge crossing
The first stage study of possible solutions for a new river crossing, preferred bridge options under consideration, artist's impressions of these and a preliminary design layout.
A report and drawings detailing a range of potential measures to mitigate any negative impacts associated with providing a new Thames river crossing.
Last updated: 10 Jul 2008
