The severe winter weather has left a huge hole in local council road maintenance budgets, according to a new survey.
Four in five local authorities had their roads badly damaged by the extreme cold, leaving a £400 million hole in maintenance budgets, the survey commissioned by the Asphalt Industry Alliance (AIA) found.
These additional costs fall on England and Wales departments already underfunded by a total of £800 million, the AIA said.
Yet 70% of local authorities do not anticipate receiving emergency funding to help meet the burden, the survey added.
The cost of bringing roads in England and Wales up to scratch in 2009/10 rose to £9.5 billion, an increase of 12% on the 2008/09 figure.
Local authorities in England reckon it would take a minimum of 11.5 years to catch up on the backlog of repairs at present rates of funding, while the Welsh backlog could take 15 years to clear.
The survey showed that the number of potholes on England and Wales local authority roads rose 40% in 2009/10. During this period, a total of 1.4 million potholes were filled in at a cost of £103 million.
AIA chairman Mike Linley said: "Although there has been a small increase in central government funding over recent years, it is a drop in the ocean compared with the amounts needed to stop the rot. Extreme winter weather would not cause so much damage if our roads were fit for purpose in the first place."
Paul Watters, the Automobile Association's head of roads and transport policy, said: "UK roads remain in such a poor state that the ravages of two severe winters in succession showed that additional central government funding has been too small to stop the rot and stave off the pothole plague this spring.
"The AA has suggested a one-off solution: diverting windfall VAT receipts from soaring fuel prices for 100 days, which would generate the emergency funds to restore UK roads to a safe condition."