One in six roads across England and Wales are in such a bad state they must be repaired within the next five years, according to local authorities.
The Annual Local Authority Road Maintenance survey (ALARM) found that 17% of roads were in “poor” condition.
The government is planning to invest 1.2bn in roads this year, which includes repair and maintenance.
But authorities say it will take an average of 12 years and 12bn to bring the local network “up to scratch”.
The survey by the Asphalt Industry Alliance (AIA) found the funding gap narrowed last year between what local highway teams received and what they actually needed to repair and maintain roads.
Despite that, councils were still nearly 730m short last year of what was required to keep the network in “reasonable order”, it said.
The AIA recommends that roads should be resurfaced between every 10 and 20 years.
Only London comes close to this, with the capital’s roads repaired every 23 years on average. The frequency of road surfacing in England is 55 years, while in Wales it is 63 years.
Alan Mackenzie, chairman of the AIA, said the message from the survey was that “highway teams simply do not have enough money to arrest the terminal decline in the condition of our local roads and the network is not resilient enough to meet the challenges ahead”.
He added that although the percentage of local roads in England and Wales classed as “good”, which means they have 15 years or more remaining, rose from 48% to 53% last year, so did those in a poor condition, rising from 13% to 17%.
Mr Mackenzie said: “This is clearly not sustainable in the long-term and many highway engineers have warned of a tipping point ahead.”
Last year, the government announced a 1.1bn investment in roads for 2017-18. This was increased to 1.2bn in January to include money from the National Productivity Investment Fund and the Pothole Action Fund.
The Department for Transport said: “It is vital councils keep our roads in a good condition to deliver better journeys for drivers.
“We are providing councils more than 6bn over six years to maintain roads and repair potholes. On top of this, we announced last autumn an additional 1.1bn to upgrade and repair roads for communities across England.”
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