MACHINES which tackle potholes by using infra-red technology to weld together road surfaces will be tried in Derby for three months.

The aim is to prevent Derby City Council from having to deal with another road maintenance crisis in severe winter weather and face quick-fix repairs.

The authority has spent more than £1m trying to get on top of a backlog of repairs and chipped in an additional £500,000 due to the damage caused by the harsh winter.

The company behind the machines, Nu-phalt, demonstrated their capability to councillors and staff.

Councillor Chris Poulter, cabinet member for neighbourhoods, and Matthew Holmes, deputy council leader and cabinet member for planning and environment, said they were impressed by what they saw.

Mr Poulter said: "What is great about this system is that we only have to visit the site once.

"At the minute we go out and mark up the site and we might do a temporary repair if it is an emergency and then go back for a more lasting repair but this machine could go out and do it all in one go."

The method uses an infra-red system which heats the pothole and the edge of the road surface around it.

It re-uses material cleared from the edges of the pothole in the filling. Some new material is also added before being compacted with a roller.

The heating system means that the infill and the existing road surface form a weld which removes the need for a seal and stops water getting back into the hole and breaking up the filling.

The use of existing material in the repair also means the council will not have to take broken road waste to landfill, which can be costly. It also reduces carbon emissions.

Simon Robson, business development manager of Nu-phalt said that in traditional repairs, carbon dioxide emissions would equate to 11 trees being felled but with their system the equivalent of just one tree.

The council will be taking the system on a three-month trial which will see its teams trained up before using it.

A metre-square section of permanent repair, done by cutting about the road surface, refilling it and then creating a join, currently costs the authority £50.

Nu-phalt's system would cost £35. The council said it would have to work out if the system could carry out as many repairs in the same time as the current system before determining if it would be good value.

But Mr Holmes said he hoped it would mean that the council would be able to provide lasting repairs.

Another system was also demonstrated. Called Velocity, it uses a high-powered hose-like system to blast out debris, add a binding liquid and spray in the asphalt to provide a very rapid repair in a matter of seconds.

Mr Holmes said: "I'm very impressed with both systems and my first impression is that both may play a part in the future needs of Derby."