Find out more about National Highways upcoming slip road and gyratory closures
National Highways is planning slip road and gyratory closures over two weekends in May to enable resurfacing works to be completed. They will also be installing a contraflow system from 7 May until the end of 2025.
Slip road closures – 9 to 12 May
From 9pm on Friday 9 May to 6am Monday 12 May the northbound A3 exit slip road, and the clockwise (westbound) M25 entry slip road will be closed.
During this time, you won’t be able to leave the northbound A3 or enter the clockwise (westbound) M25 entry at junction 10. The A3 and M25 will remain open, as will all other slip roads. You will still be able to:
- leave the clockwise (westbound) M25 to join the A3 in either direction
- leave the anticlockwise (eastbound) M25 to join the A3 in either direction
- leave the southbound A3 to join the anticlockwise (eastbound) M25
Gyratory closure – 16 to 19 May
The Wisley interchange junction 10, including all entry and exit slip roads, will be closed in its entirety from 9pm on Friday 16 May to 6am on Monday 19 May
The M25 and A3 will both remain open during the closure, but the slip roads and roundabout at junction 10 will be closed. Drivers will not be able to change from the A3 to the M25 or vice versa.
Diversion information and maps for the closures can be found via National Highways website.
Contraflow on the A3
National Highways will be operating a contraflow system on the A3 from 6am Wednesday 7 May.
The system will be in operation on the northbound and southbound A3 between the M25 junction 10 and the Ockham Park roundabout.
The contraflow means National Highways can keep three-lanes running in both directions whist they widen this stretch of the A3.
On the northbound side of the A3 there will be three lanes for northbound traffic and one lane for southbound traffic. On the southbound side there will be two running lanes for southbound traffic. The contraflow will be in operation 24/7 until the end of the year.
If you are travelling on the southbound A3, the following lane designations will be in place once you’ve passed the M25 exit:
- The inside lane (lane 1) will be for HGVs and traffic wishing to exit at Ockham Park roundabout (including RHS Wisley visitors), and traffic wishing to remain on the A3 towards Guildford.
- The middle lane (lane 2) will be for non-HGV traffic who wish to stay on the southbound A3 towards Guildford. If you’re in this lane you will not be able to exit at Ockham Park Roundabout.
For more information about the contraflow system, please visit National Highways website.
Who can I contact about the works?
If you have questions about the project, you can contact National Highways by emailing info@nationalhighways.co.uk or calling 0300 123 5000. There are also updates on the project on social media – on National Highways X/Twitter and Facebook accounts.
You can also sign up to our Highways Update newsletter to get the latest updates on the closures and other highways issues from across the county. Don't forget to follow the Surrey Highways Facebook and X accounts.
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