Annual RAC bridges report reveals 3,105 substandard structures in UK

men at work to maintenance a bridge over highway

Devon County Council is responsible for more bridges than any other authority in the UK - Credit: Getty Images/iStockphoto

It’s that time of the year again when the RAC Foundation release their annual bridge report and this leads to my emails working overtime as Devon, who freely contribute to the findings, always feature in this report which states:
Local authorities in England, Scotland and Wales have identified 3,105 bridges – defined as structures over 1.5m in span – as being substandard. This was 1.6% up on the 3,055 figure twelve months before.
The analysis is based on data provided by 199 councils out of the 206 asked.

Between them, the councils are responsible for maintaining 71,656 bridges meaning 4.3% of the inventory is substandard.
Councils also reported that, at the time they responded in Autumn 2020, ten bridges across Great Britain had fully collapsed in the previous 12 months. A further 30 had partially collapsed.
Of the 10 full collapses, 7 were in Aberdeenshire. Caerphilly, Derbyshire and Dumfries & Galloway had 1 each.
The 30 partial collapses were in: Powys (6); Conwy (5); Denbighshire (3); Dumfries & Galloway (2); North Yorkshire (2); Perth and Kinross (2); and Barnet, Buckinghamshire, Fife, Gwynedd, Lincolnshire, Merton, Neath Port Talbot, Peterborough, Somerset and Stirling (one each).

However, don’t be alarmed because Devon County Council is responsible for more bridges than any other authority in the UK and we’re recognised as one of the UK’s leading authorities in structures asset management.
The term ‘substandard’ does not mean there is a problem with the bridge, it means we are managing 233 bridges that cannot carry the full 40 tonnes ‘standard’ highway load and only three of these need upgrading. In 2019 this figure was 244. Ninety of these are ‘clapper’ bridges on Dartmoor National Park, which are performing well, and the remainder are either scheduled for strengthening work or have a weight limit. 

Those with weight limits are suitable for the road they are on, such as small lanes where large vehicles are unlikely to require access. We manage our bridge stock effectively in accordance with national guidelines to maintain the safety of the public.
Readers of my column may also be interested in the comments Devon’s chief Engineer made to the RAC Foundation following this years survey:
“While the number of substandard bridges may appear worrying there is often a good reason why a bridge falls into this category; it does not mean the bridge is unsafe as it will be managed by the Local Authority usually by a weight limit. A restriction such as this may be wholly appropriate for the class of road and/or location. However, the survey shows Local Authorities would want to remove 2,256 bridges out of this substandard category which can only be achieved by more investment through Government funding”.

Devon has been ahead of the game for scour inspections and assessments for the last decade and spends a not insignificant portion of the annual capital budget on this important area. We also have one of the UK’s leading experts on scour research in Dr Diego Panici as a member of the bridges group and we have had several research papers published on the subject, with Devon County Council getting credit.
The RAC Foundation is a useful body to lobby Government for extra investment in our highways, so while we shouldn’t be concerned about the statistics for Devon as we do have a good management system in place, the data could be useful when the Department for Transport looks at where to allocate funds.