by Luke Hollands

The M20 is to become one of only three motorways in the UK where the police can enforce variable speed limits.

Changeable limits have been displayed on gantries between junctions 4 (West Malling) and 7 (Detling) since 2007 but only for advice.

From the end of August police will be able to enforce limits using cameras to catch motorists driving too fast.

Variable speed signs are displayed on motorway gantries across the country but the M20 will be only the third place in the country where limits can be enforced by law.

The other two stretches of road are on the M25 and the M42.

The scheme comes after a public consultation by the Highway Agency last year.

More than 40 per cent of people who took part in the consultation objected to the plans, with some criticising it as a money-making scheme and others calling it flawed.

Highways Agency regional performance manager Barry Westwood believes the scheme will help the flow of traffic and improve safety.

He said: “It will bring great benefits to drivers on this busy section of the M20, helping to reduce congestion and make drivers’ journeys safer and more reliable by smoothing traffic flows.

“The system is already being used successfully on the M25.

"It has helped to make the motorway safer by reducing the frequency of collisions by 10 per cent and by encouraging drivers to keep within the speed limits to provide smoother, more reliable journeys during peak times.”

The system will work by using sensors in the road to detect the speed, volume and flow of traffic.

It will then calculate a speed designed to keep traffic moving and in theory reduce the level of stop-start traffic that leads to congestion.