The Highways Agency has begun a consultation on highly controversial plans to use the hard shoulder as a running lane for cars and lorries on the M25 in Kent and Surrey.
Critics including the police and the AA insist it could be lethal with motorists left stranded in the dark on the main carriageway if they break down. They say it is a "scheme on the cheap" because the section of the road will no longer have a hard shoulder for people to pull off and it will have fewer safety areas than other motorways where a similar changes are in operation.
The section is between junctions 5 (Sevenoaks) and 7 (for the M23).
Introducing these new measures on a section of motorway requires legislative changes through the drafting of new Regulations. The Highways Agency has published these draft Regulations as part of a six-week consultation, which will finish on 5 November 2012.
John Martin, Highways Agency project manager, said: “This major upgrade will ease congestion and make journeys more reliable for the thousands of drivers, including hauliers and commuters, who use this section of the motorway every day.
"Our experience elsewhere shows that such an upgrade will deliver significant safety and journey time benefits."
The scheme will enable the Highways Agency to manage traffic flows during periods of peak congestion or following an incident by slowing down vehicles or closing lanes to smooth out traffic and reduce the risk of further collisions. The hard shoulder will also be opened up to traffic.
The system uses sensors in the road surface to detect the speed, volume and flow of traffic. It then calculates the optimum speed to keep traffic moving and reduce the level of ‘stop-start’ traffic which leads to congestion. Drivers see the current speed limit displayed on electronic signals on the overhead gantries.
Preparatory work for the scheme began this month, with main construction work due to start next Spring.