Drivers tempted to bypass the official diversion for this weekend’s M25 motorway closure have been warned of potential ultra-low emission zone (Ulez) charges if they stray off course.
The London orbital motorway is having its second ever planned closure, with a busy stretch in the south-west closed in both directions for works, potentially bringing long delays and congestion for thousands of drivers.
National Highways has urged motorists to avoid travel if possible or stick to the official diversions. Drivers of non-Ulez-compliant vehicles entering the clean air zone will not be charged as long as they stay on the marked route, but will otherwise be liable for the £12.50 charge if they follow their satnav for an attempted shortcut.
Only petrol vehicles more than 18 years old or diesels more than nine years old are normally liable for the charge, which was expanded to cover the whole of Greater London last year.
The M25 will be closed in both directions between junctions nine and 10 in Surrey from 9pm on Friday until 6am on Monday while concrete beams for a new bridge and a gantry are lifted into place.
The diversion for those who wish to rejoin the motorway runs for 19 miles along A-roads in Surrey and Greater London.
Jonathan Wade, a National Highways senior project manager, told the PA news agency: “Although the (Ulez) cameras will be active, no enforcement action will be taken. However, if you ignore the diversion signs and do your own thing, then if your vehicle’s not compliant, you do run the risk of getting caught.”
The traffic agency has urged drivers to follow the main route to minimise the risk of rural gridlock, with thousands of cars normally using the stretch of motorway every hour.
This weekend is the second of five planned closures of the M25 in a £317m works scheme, after the first ever planned daytime shutdown in March on the neighbouring stretch from junctions 10 to 11.
Fears that the zigzag diversion routes then used between Cobham and Woking would host epic jams were eventually unrealised, with only a third of the normal volumes of traffic using the roads after a widespread awareness campaign.
However, Wade said there was a “very real” risk that the benign outcome of early March could make motorists complacent about the fresh warnings to reassess journeys.
Other stretches of the M25 will also be disrupted this weekend, with work to retrofit more emergency refuges on its sections designated as smart motorway with no hard shoulder.
The RAC also warned of more congested roads ahead, with this week’s national rail strikes potentially forcing more travellers into cars.
The M25 will close for three more weekends this year, with the next one scheduled for August. The works will increase the number of lanes and improve junction 10, one of Britain’s busiest motorway junctions.
