Northumberland has nearly 100 substandard bridges which will cost £230m to fix, according to research by the RAC
The RAC Foundation said there was only so long councils could continue to "patch things up before bigger cracks literally start to appear" in road infrastructure.
Figures from the RAC Foundation show that of the 977 bridges in Northumberland, 93 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 estimates it would cost £230 million to bring the road bridges back to good condition.
Across Great Britain, councils said 3,090 bridges were substandard – accounting for 4.3% of the total 71,925 bridges. It was down slightly from 3,211 substandard bridges reported the year before (4.5%).
The estimated one-time cost to clear the maintenance backlog on bridges across the nations is £5.9 billion.
Steve Gooding, director of the RAC Foundation, said the figures revealed the challenge local authorities were 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," Gooding added.
"Whether it is potholes or bridges, there is only so long that councils can continue to patch things up before bigger cracks literally start to appear in the road network."
No collapsed bridges were reported across Great Britain last year, but there were 14 partial collapses.
David Renard, transport spokesperson for the Local Government Association, said: “Not all bridges are the responsibility of councils, but for those that are, they are doing their best to ensure they are well maintained and withstand extreme weather, the like of which communities have been experiencing for much of the last few months.”
Northumberland County Council said it would ideally restore 87 bridges to full capacity, but only foresees 20 returning to good condition in the next five years.