Lancashire drivers told they will 'notice the difference' after specialist pothole-filling machines go on a summer spree

Lancashire County Council says that it has spent £1m on fixing surface defects using an innovative high-pressure device. The method - known as spray injection patching - can achieve up to 200 repairs a day per machine.

>» See the machines at work here

The authority has doubled its budget for this particular repair technique compared with last year - and four of the patching machines are currently at work throughout the county.

Spray injection patching is particularly suited to improving Lancashire's 700 miles of rural roads, County hall says, because the speed of each repair means that the machines “can cover a lot of ground”.

They are being used in a preventative way to 'find and fix' on roads where most potholes are being reported, while also sealing smaller defects as they move along, helping prevent more potholes appearing in future.

Thee machines work using a multi-functional hose which initially blasts compressed air to remove all dust, debris and water from the affected area. Once the defect has been cleaned, a cold bitumen emulsion is applied to seal it.

An aggregate mix is then fired in at high speed, along with another coating of bitumen emulsion to form a high-quality repair.

County Cllr Rupert Swarbrick, cabinet member for highways and transport, said: "We're investing around £35m in our highways this year, and have doubled the budget for spray injection patching to bring our rural roads into better condition.

"We have a very extensive rural network in Lancashire and this method is a really efficient and cost-effective way of getting on top of the repairs which are needed, which we simply couldn't do within the same time and budget using traditional techniques.

"The cold and wet Lancashire winters means that it's always a challenge to keep our roads in good condition, however all the maintenance we're carrying out at the moment will make a real difference by the end of the summer."

The specialist machines work by using a multi-functional hose which initially blasts compressed air to remove all dust, debris and water from the affected area. Once the defect has been cleaned, a cold bitumen emulsion is applied to seal it. An aggregate mix is then fired in at high speed, along with another coating of bitumen emulsion to form a high-quality repair.

It is estimated that, last year, over 18,500 spray injection repairs were made on Lancashire's roads, based on the volume of surfacing material used.