Millions of pounds are needed to restore substandard bridges in Cornwall to good condition, new figures show.

The RAC Foundation said there is only so long councils can continue to “patch things up before bigger cracks literally start to appear” in road infrastructure.

Figures from the RAC Foundation show that of the 1,009 bridges in Cornwall, 98 were substandard last year.

Substandard means bridges are either too weak to carry 40-tonne vehicles or there is a weight restriction for environmental reasons, such as a narrow bridge or narrow approach roads.

The council estimated it would cost £5.9m to bring the road bridges back to good condition.

Across Great Britain, councils said 3,090 bridges were substandard – accounting for 4.3 per cent of the total 71,925 bridges. It was down slightly from 3,211 substandard bridges reported the year before (4.5 per cent).

The estimated one-time cost to clear the maintenance backlog on bridges across the nations was £5.9bn.

Steve Gooding, director of the RAC Foundation, said the figures reveal the challenge local authorities are wrestling with to protect critical road infrastructure.

“The numbers illustrate how important it is for significant sums of money to be spent tackling at least the higher priority work,” said Mr Gooding.

Cornwall Council said it would ideally restore 75 bridges to full capacity, but only foresees one returning to good condition in the next five years.

A spokesperson for the Department for Transport said: “The Government is providing more than £5bn of investment over this Parliament to local authorities across England to support the maintenance of their local highway infrastructure, including the repair of bridges and the resurfacing of roads up and down the country.”