A further 50 miles of the M25 should be widened to four lanes, using funding generated by road charges on major routes in and around London, according to the final draft of a government-commissioned report released today.
If regional consumer resistance to congestion charging proved too strong, then the only way to expand the traffic-choked motorway would be to impose a 3p a mile toll directly on motorists using the widened sections, the study suggests.
Additionally, ramp metering, where flow of vehicles on to the motorway is controlled by traffic lights on access roads, could be introduced. Cars with four passengers might be given priority over vehicles with only one person.
The report, produced by consultants Kellogg Brown & Root, and commissioned by the Government Office for the South East, is the main outcome of the Orbit-Transport study. Its primary purpose was to devise means of improving the reliability of journeys on the M25.
The study will be submitted to the London mayor, Ken Livingstone, and regional planning boards for the east and south-east of England. They will add their recommendations before it is given to government ministers.
Several sections of the M25, on the west and other busy stretches, are already due to be widened in 2004, making them in some cases six lanes wide. The new areas the KBR report suggests need to be expanded to four lanes each way are between junctions five and seven near Redhill, Surrey; between junctions 16 and 23, on the north-west segment of the M25; between junctions 27 and 31, from the M11 to the Dartford river crossing east of London; and from junctions 1b to three in Kent. The work would cost an estimated £850m.
Road charging in the south-east should spread as far as Aylesbury in Buckinghamshire, Guildford in Surrey, Maidstone in Kent, Chelmsford in Essex, and Stevenage in Hertfordshire, the study suggests. The report envisages vehicles paying around 10.5p a mile by the year 2011.
The report's author, David Hardcastle, of KBR, said: "Ideally, we would like to see widening to the M25 accompanied by road-user charging nationwide. Widening alone is likely to encourage extra traffic, that in turn would lead to further congestion."
Government forecasts suggest that, between 1997 and 2016, the number of cars in the Orbit study area will rise by 34%. Unless improvements are made, it is likely to take an extra 21 minutes to travel all the way round the M25 in 2011 compared with 1997 (a rise of 14%).
The report found that improving public transport and getting more freight to travel by rail would have little impact on the M25. One suggestion is that making insurance companies, rather than tow-away contractors, responsible for damage to broken down or crashed vehicles might bring speedier removal of carriageway obstructions.
The AA did not welcome the idea of tolls. "The M25 is the busiest motorway in Europe," a spokesman said. "To manage demand [there should be] tunnels or widening at pinchpoints. The variable speed limit should be extended to cover the entire motorway."
