It would take ten years to clear the backlog of repairs to roads across the West Midlands, according to a new study.

The Annual Local Authority Road Maintenance (ALARM) survey carried out by the Asphalt Industry Alliance claimed that the region was facing a pothole crisis.

But Birmingham City Council, which has signed a £2.7 billion private finance initiative partnership with private company Amey, claims the deal had meant a huge surge of investment in the road network.

And Amey told the Birmingham Post that it will have cleared the entire repair backlog within the city by June next year.

The study said that on average across the region a road can only expect to be resurfaced once every 75 years.

There are 20,146 miles of local authority controlled highways in the West Midlands, and more than 2.8 million vehicles registered here.

On average local authorities in the region filled in 9,875 potholes in the last 12 months, and incurred additional unforeseen costs of repairs of more than £400,000 each. According to the ALARM survey the average cost of tackling each pothole is around £56.

Some councils in the region have been hit by huge additional repair bills because of natural disasters and extreme weather, with highways departments anticipating worse roads condition to come.

In Worcestershire which was badly hit by flooding, an extra 6,400 potholes were repaired in the first two months of the year, costing an extra £700,000.

From June 2012 to May 2013 – a total of 11,335 potholes were filled in across Birmingham. On average each local authority in the Midlands is thought to face a one off cost of £50 million to clear up the backlog.

On Birmingham, Amey said: “The five-year programme of improvements to the city’s roads, footways, bridges, tunnels, street lighting and traffic control systems is tackling the issue of outstanding maintenance and is expected to be completed by June 2015.

“One of the benefits of Birmingham City Council’s partnership with Amey is that the repair of potholes and other highways defects, which also includes footways, structures, street lighting and traffic control systems, is built in to the 25-year deal, meaning that the cost to the authority doesn’t change despite any fluctuation in the number of call-outs.”

A Birmingham City Council spokesman added: “The partnership between Birmingham City Council and Amey continues to deliver a higher level of investment in the city’s highways than could have been achieved previously, and the improvements are evident across all areas of the city. Birmingham is in a unique and enviable position because we have been able to plan works more efficiently and, through the partnership, we are able to ensure that the improved standards will be maintained until 2035.”

Urging central Government to introduce an “invest to save” policy, the Asphalt Industry Alliance’s Chairman, Alan Mackenzie said: “These figures are disappointing for everyone who has worked hard together on the Highway Maintenance Efficiency Programme (HMEP) initiated by the Department for Transport.

“It’s thanks to HMEP that so many highways departments have successfully made the case to their councils to invest in more repair to avoid further deterioration and costs.

“To see that work washed away is discouraging to say the least.”