The humble pothole is usually held up as the prime, and most obvious, example of where a lack of funding for road maintenance leads to.
However, the RAC Foundation’s now-annual survey of the state of bridges across Britain shows that at both local and national levels keeping our highways up to scratch extends beyond filling in and smoothing out surface blemishes, common and troublesome as they might be.
Our latest analysis reports that of the 72,000 structures local authorities are responsible for just over 3,000 – around 4% of the total – are so-called substandard, meaning they are unable to carry the heaviest vehicles that now routinely travel the length and breadth of the country.
In the absence of funding to upgrade or repair, many of these bridges will operate with weight restrictions meaning potentially long detours for the drivers of prohibited vehicles. Of course, there will be those bridges, perhaps centuries old, which were never designed for today’s volume and type of traffic, and which are still well off the beaten track and rarely used. But there will be others that are on key arteries.
Interestingly, in some cases weight restrictions are put on bridges not to protect the structures themselves but to preserve the roads that run across them. In Blackpool for example several bridges on the same route have restrictions because the road surface itself is vulnerable to damage caused by the largest lorries.
The cost of clearing the backlog of work on all – not just the substandard – council-managed bridges now stands at £6.7 billion, a rise of a third in just a year. The danger is that a significant number of the currently deemed adequate will slip into the substandard category if they aren’t adequately cared for.
The awful consequences of a catastrophic bridge failure were highlighted all too graphically in Italy last year when 43 people died after the collapse of the Morandi Bridge in Genoa.
Whilst ministers and road managers here have been at pains to say that there are no structures in Britain of the same design, this year’s RAC Foundation study did reveal that there are at least 600 so-called post-tensioned council bridges with hidden strengthening cables that require intrusive examinations. These need specialist equipment and knowledge to carry out and hence can be very expensive to do. According to what councils told us some of these bridges will never have had an in-depth survey.
The positive news is that the Department for Transport is aware of the problem and has allocated a number of pots of money which councils can apply for to try and limit, if not reverse or clear, the outstanding list of maintenance work.