WHO, WHAT, WHY?
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Roads in the North and in Scotland have far more potholes than in the South, suggests new research. Why?
HOW POTHOLES ARE FORMED
Water penetrates crack in the road caused by traffic
Water freezes and expands, causing rupture of asphalt surface
Ground thaws and water melts, leaving a space
Stress from traffic causes shell to cave in and hole to form
The further north you drive, the more likely you are to damage your car with a pothole, according to a study.
Nine of the worst 10 regions for axle and suspension failure, related to potholes, are in the north of England and Scotland.
Ayrshire in Scotland has the highest rate - 14% of cars each year require repairs relating to poor road quality - and Oxfordshire has the lowest rate, where 4% of cars suffer similar failures each year. Total costs incurred by motorists top £1m a year.
"It's incredible how clear a North-South divide these figures appear to show," says Duncan McClure Fisher, managing director of car insurer Warranty Direct, which carried out the research by evaluating claims over an eight-year period.
He adds: "Whether this is due to colder weather causing more northern roads to crack or just poor maintenance, it seems to underline a clear difference in the condition of highways across the country."
Potholes are formed by water penetrating the asphalt surface through cracks caused by traffic. When temperatures plunge, the water freezes, expands and causes the surface to rupture.
Research into insurance claims over eight years suggests there are more potholes in the North and Scotland
This could be due to the colder temperatures
But this year's cold winter in the South has increased the problem
When the ice melts, it leaves a void below the surface, which caves in under the stress of vehicles and eventually forms a pothole.
This freeze-thaw cycle is the main reason why potholes form, so it should be little surprise that there are more the further north you travel, says a spokeswoman for the National Joint Utility Group, which represents utility companies on issues of road repairs.
"The main reason for potholes is the variance in temperature," she says. "The North and Scotland have more extreme temperatures than the South and that's probably the main factor."
But Nick Boyle of ASI, which carries out repairs to potholes for councils across the UK, says he is surprised the survey suggests any regional variations.
"I would have thought the whole country was on a par. The roads are in a shocking state at the moment and every local authority seems to have had its funding cut."
Ayrshire - 14.05% of all cars
Northumberland - 13.84%
Renfrewshire - 13.58%
Angus - 13.36%
County Durham - 13.07%
Aberdeenshire - 11.6%
North Yorkshire - 11.21%
Warwickshire - 10.56%
Lanarkshire - 10.48%
Tyne and Wear - 10.23%
Source: Warranty Direct
Although there was some logic to a pattern because of the warmer temperatures further south, Mr Boyle says the harsh winter this year experienced in the South has left many roads in a very bad way. One area near Milton Keynes he described as a "disaster".
As well as the snow compounding the freeze-thaw effect, the road repair budgets were spent on importing salt, he says, and salt degrades the road surface even further.
Although the weather plays a part in forming potholes, it's up to councils to fix them, unless they are on a trunk road or motorway and then it's the responsibility of the Highways Agency. And the performance of councils varies according to their resources and priorities.
When questioned, a spokesman for the Local Government Association wasn't aware of a difference between the North and the South, although it would make sense that the weather was a factor.
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"It could also be related to the amount of money a council has to spend on the potholes."
Councils spent £53m on pothole compensation claims last year - more than the £52.3m that was actually spent fixing the problem, he says.
"A culture created by no-win-no-fee lawyers is preventing us from getting on with fixing the problem."
Add your comments on this story, using the form below.
I'm fairly sure this is wrong as Southampton has more potholes per square meter than anywhere on Earth. Official.....
Matthew Corkhill, Southampton
There is an enormous pothole on my street - which is on just about every major bus route in Glasgow - which was "fixed" a couple of months ago, only to reappear about a month later. All those buses can't help, but they clearly aren't fixing potholes very well in the first place. If the "compo culture" disappeared, would councils spend this extra £53m on fixing potholes? Why on earth do we allow people to sue councils and public services anyway?
Douglas Daniel, Glasgow, Scotland
I live in York, where several major routes are littered with potholes larger than speed bumps, but the council rarely does resurfacing. In Southampton, where I used to live, they would resurface roads only half as bad. The standards are obviously different.
My god if the roads up north are worse than here then the country is in a very, very poor state of affairs. It's bad round here as it is.
The money we pay towards the roads needs to be spent on the roads and nothing else. Road tax is not for wars, bailing out failing banks, MP's expenses or anything else other than repairing the roads so why are we letting them get away with squandering our money so unaccountably?
Jenny, Stevenage, Herts
Highway maintenance has been chronically underfunded for more than 25 years, and there is a massive backlog of structural maintenance required nationally. Apart from weather effects, structural damage to carriageways is caused by heavy vehicles, and investment has never been adequate to compensate for heavier vehicles permitted by the EU. Private cars have negligible effect on surfacing, and slow moving heavy vehicles including buses affect the structure most. The adverse weather conditions this winter have just accelerated matters.
Councils also have to spend a disproportionate amount of money dealing with reactive footway repairs in order to avoid potential accidents to pedestrians. Ideally, the local authorities would be able to implement value for money Asset Management, but too much of the budget goes on "fire-fighting".
Jan, West Midlands
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