CONGESTION CHARGING will only cut journey times around the M25 by 17 minutes, government transport consultants said last week.
But they warned that time taken to travel round the whole motorway would rise by 21 minutes to 171 minutes if nothing was done.
These conclusions are among the many scenarios mapped out by consultant KBR in its Orbit Multi-Modal study, published last week.
The study recommends widening 80km of the M25 as exclusively revealed in NCE last month (NCE 24 October).
It calls for the M25 to be widened from three to four lanes in each direction at four sections. This would cost an estimated £850M (see map).
As expected, the study, carried out by KBR and independent consultant Denvil Coombe, advises the government not to complete the widening until it is possible to restrict use of the motorway.
It presents three 'demand management' options to ministers.
The least controversial is to widen the motorway and install traffic signals on slip roads to the widened sections. These would restrict access to the M25 at busier times.
A second option would result in the addition of an extra lane that would be electronically tolled at 3.2p a mile raising an estimated £58M a year.
Option three is to charge for use of trunk roads in the area around the M25 at 10.5p/mile plus use of the motorway itself.
This could raise an estimated £3.4bn a year.
The report says that if transport secretary Alistair Darling chooses area-wide charging, the time it would take to circumnavigate the motorway would go down from 150 to 133 minutes.
If the motorway is widened without congestion charging, the journey time would go up to 171 minutes.
The consultants said that at least some revenue from charging should be spent on improving public transport around the M25. This could include setting up an orbital bus system or better rail access to Heathrow Airport.
INFOPLUS www. orbitproject. com