Analysis of two sections of all-lane running (ALR) on the M25 suggests that up to 20% of drivers are ignoring ‘red X’ signs on smart motorways.
First introduced in 2014, smart motorways use variable speed limits to manage traffic and tackle stop-start congestion.
The hard shoulder is turned into an ‘active lane’, with gantry signs displaying a red X indicating if a lane is closed – usually as a result of a vehicle breakdown or in the event of a collision.
The data comes from two annual reports – carried out by the engineering and design company Atkins on behalf of Highways England – which focus on the ALR sections between junctions five and seven, and 23 and 27 on the M25.
The third year reports, which cover the period May 2016 to April 2017, show that up to 20% of traffic flow ignored ‘red X’ signs on both sections of the motorway.
The report states: “Non-compliance in this sample ranges from one to 15 vehicles per minute, 0% to 20% of total flow.”
With regard to ‘total compliance’, the year-on-year rate fell by 2% on the J23-27 section – from 96% in the second year to 94% in year three. Between J5-7, compliance rates remained at 94%.
In terms of safety, the ALR between J5-7 exceeded Highways England’s objective of ‘maintaining safety’, by ‘significantly improving it’ – while the ALR at J23-27 ‘met its safety objective’.
Traffic flow on the section between J23-27 has improved by 16% – with ‘capacity for more growth’.