Map shows where huge chunk of M25 will be closed from tonight
Here's the areas you need to avoid.
A seven mile stretch of the M25 is set to shut down in both directions this weekend.
Motorists have been advised to avoid the area between junctions 9 and 10 in Surrey – from 9pm on Friday to 6am on Monday morning.
Instead, drivers have been urged to stick to the planned 19-mile diversion route, which will send vehicles through parts of Surrey and Greater London.
People have been urged to ‘only travel where necessary’.
National Highways said: ‘We’re grateful to all drivers last time who avoided the closure and completed their journeys in other ways. We urge you to do the same again.’
The closure is the second of five planned on the motorway after junctions 10 and 11 were temporarily shut down in March.
What is the official diversion route?
There is a 19-mile diversion in place using the A3 and the A240 which will be signposted to drivers. It goes via Epsom and Chessington, dipping into the ULEZ zone.
The full route is listed here by National Highways, with a separate one for high vehicles.
Although there were fears the closures in March would lead to widespread congestion, it was later reported traffic through the diverted areas was down around two-thirds after a widely shared awareness campaign.
Those travelling to or from Heathrow and Gatwick airports are set to be the worst affected, with the National Highways warning motorists it expects long delays.
Can I be fined under ULEZ rules?
The diversion briefly goes within the ULEZ (ultralow emissions) zone, but no drivers will be fined if they stay on the approved route as enforcement will be suspended during this time.
National Highways senior project manager Jonathan Wade 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.
‘You’ll be perfectly safe as long as you follow the diversion routes.’
RAC spokesperson Alice Simpson also warned drivers not to rely on their sat navs during the closure.
‘Planning ahead is absolutely vital,’ she said.
‘Rather than relying on a sat nav, check the planned diversion routes ahead of time and be prepared for long delays.
‘It’s also a really good idea to check your vehicle’s oil and coolant levels, tyre pressure and tread depth all before setting off to reduce the chances of a very unwelcome breakdown.’
Vehicles diverting from the planned diversion routes which do not comply with ULEZ standards will have to pay the £12.50 daily fee if their vehicle does not meet minimum emissions standards.
Failure to pay the charge when required can result in a £180 fine, reduced to £90 if paid within 14 days.
Why is the M25 closing?
It is so that a new bridge can be installed this weekend, the next stage of works started in 2022.
The extent of the major roadworks can be seen in a video including footage from the works in March, when a bridge was demolished creating 3,000 tonnes of concrete waste that took 80 trucks more than 24 hours to clear.
The project, which will continue until summer 2025, is intended to restore heathland and upgrade the junction with the A3 Wisley Interchange to ‘reduce congestion, improve safety and create more reliable journeys’.
It will include the UK’s first ‘heathland bridge’ to offer a natural corridor for wildlife over the motorway.
What area does ULEZ cover?
It operates across all London boroughs after it was expanded in August last year, but the M25 is not in the zone.
It covers the entirety of the outer London counties including Kingston Upon Thames, Croydon, Enfield and Hillingdon, but not the surrounding home countries such as Kent, Surrey, Essex and Hertfordshire.
Which vehicles are affected by ULEZ charges?
It applies to cars, motorcycles, vans, specialist vehicles up to 3.5 tonnes, and minibuses up to and including 5 tonnes.
Large vehicles such as buses, coaches, and lorries are subject to different requirements.
Petrol cars subject to the charge are generally only those registered as new before 2005, while for Diesel cars it is those registered before September 2015.
For vans, it is 2006 and 2016 for petrol and diesel respectively, and motorbikes affected are generally those registered before 2007.
You can check if your vehicle will be charged using the registration number here.
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