Smart motorways use technology to manage the flow of traffic to improve journey reliability and reduce congestion while maintaining safety. This upgrade is the second phase of a scheme which will see road users benefit from an increase in road capacity by a third on the 16.8 miles of the M25 between junctions 23, Potters Bar and 27, with the conversion of the hard shoulder into a running lane for traffic. Roadside and overhead gantries will provide information that will smooth traffic flows and improve journey reliability.
John Martin, Senior Project Manager at the Highways Agency said:
We will be installing overhead gantries, some of which span the entire motorway, which will provide drivers with traffic information which will improve journey reliability and reduce the likelihood of ‘stop-start’ traffic flow.
We have planned the work to take place overnight, when traffic flows are lowest, with a closure in one direction only in order to minimise disruption. Where the M25 is closed in one direction, drivers will be able to continue their journeys by following a clearly signed diversion route.
The installation work will take place overnight from 10pm to 5.30am between Mondays and Thursdays, from 11pm to 6am on Fridays and from 10pm to 6am on Saturdays. No work is planned to take place on Sunday nights. When the M25 is closed clockwise between junctions 25 and 27, road users will be diverted via the A10, A406 and M11. When the M25 is closed anti-clockwise between junctions 27 and 25, road users will be diverted via the M11, A406 and A10.
The next overnight closures are scheduled for Monday 17 March to Thursday 20 March on the M25 clockwise between junctions 25 and 27 for the installation of a superspan gantry across the entire motorway. During the closures, traffic on the anti-clockwise carriageway will be temporarily stopped using a rolling roadblock when the gantry is lifted into position.
Further closures will be publicised in advance.
Last summer, gantries were installed on the M25 between junctions 23 and 25. You can view an earlier installation of a superspan gantry at junction 24 on YouTube.
Members of the public should contact the Highways Agency Information Line on 0300 123 5000
Journalists should contact the Highways Agency press office on 0844 693 1448 and use the menu to speak to the most appropriate press officer