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The scheme
The head of the project at the Highways Agency, David Grant, explains how the scheme works and some of the results achieved.
In September 2006, an 11 mile stretch of the M42 near Birmingham became the first motorway in the UK to dynamically use the hard shoulder as a normal running lane. The scheme, called Active Traffic Management, has since come under the international spotlight for its innovative application of the latest technology to cut congestion.
How does it work?
Variable speed limits, determined by inductive loops, are displayed on overhead gantries incorporating an extra signal over the hard shoulder. This signal displays a speed limit to indicate to motorists when the hard shoulder is available as an extra lane. Operators at the control centre keep the hard shoulder in a ‘ready to run’ state by using CCTV to check it for debris and vehicles before opening. This system works well, with 93% of drivers surveyed saying that they felt it was clear when they should and should not use the hard shoulder.
Safety
Safety was paramount to the design of the scheme and additional features have been added to make the system as safe as possible. Large lay-bys, or emergency refuge areas, have been built behind the hard shoulder approximately every 500 metres for broken down vehicles. They contain the latest emergency roadside telephones linking motorists to the nearby regional control centre.
Control centre operators also have access to over 190 CCTV cameras, allowing them to spot any incidents or breakdowns quickly. They can immediately close any affected lane(s) by displaying a red ‘X’ on the digital signs. This flexible approach also allows emergency vehicle access in the event of a major incident.
Critically, initial fears from safety 1campaigners have proved unfounded as the number of accidents on the stretch has actually decreased – from 5.1 a month to 1.5 a month.
What are the results?
As well as the decrease in the accident rate, the scheme has achieved some excellent results and has demonstrated that innovative thinking can really help beat congestion. Use of the hard shoulder in peak periods saw average journey times fall by more than a quarter on the northbound carriageway and drivers’ ability to predict their weekday journey times improved by 27%. Overall fuel consumption reduced by 4% and vehicle emissions fell by up to 10%.
The scheme is also popular with motorists, with 68% saying they felt more informed about traffic conditions and 60% saying that they would like to see it extended elsewhere on the motorway network.
What’s next?
Ruth Kelly has announced a £150m extension of the scheme in the West Midlands, with hard shoulder running being added to two stretches of the M6 and variable speeds limits being added to stretches of the M42, M40 and M6. The Transport Secretary has also ordered a major feasibility study to determine where else on the motorway network could benefit from the innovative techniques in use on the M42.
One thing is for certain – hard shoulder running looks set to play a key role in the way traffic is managed on our motorways for some years to come.
For more information on the Highways Agency or Active Traffic Management please contact the Highway Agency (08457 50 40 30; website www.highways.gov.uk).
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