• Six weeks of overnight closures of A801 for works on M8 bridges at J4 over local road roundabout

• 3 weeks of overnight closures A801 northbound from 6 July 2026 followed by 3 weeks southbound from 27 July 2026

Overnight concrete investigation works to the twin-deck, three-span bridges carrying the M8 over the A801 at Junction 4, Whitburn Interchange, are set to begin on Monday 6 July 2026.

Transport Scotland’s operating company, BEAR Scotland, will carry out the six-week project, which requires a series full overnight closures of the A801 northbound, then southbound, to allow the various elements of the bridges to be fully investigated safely.

The project is essential to understanding the structural integrity of this crucial piece of infrastructure for years to come. The investigation works involve a series of site survey tests and chemical tests, at a number of locations on the 56 year old bridges.

The northbound mid-section of the roundabout, which carries the A801 below the M8, is planned to be closed between 20:00 and 06:00 on week-nights (Monday – Friday) from 6 July 2026 to 25 July 2026.

This initial three-week phase of the project will be followed by a further three weeks of overnight closures of the southbound mid-section of the roundabout carrying the A801 below the M8. Again, it will be week-night closures between 20:00 and 06:00 from 27 July to 15 August 2026.

Use of all slip roads and approaches to the roundabout will be unaffected throughout the six-week overnight programme.

Signposted diversions for phase one A801 northbound closures 6 July – 25 July

• Westbound M8 traffic seeking to exit at Junction 4 and join the A801 northbound will be advised to remain on the M8 westbound and instead exit Junction 4A, Heartlands, before returning via the M8 eastbound to exit via the Junction 4 eastbound off-slip, from where they can join the A801 northbound. This diversion will add an estimated four miles and four minutes to affected journeys.

• Westbound traffic on the A705 Main Street wishing to join the A801 will be directed to continue past the turn for the A801 and, at the end of West Main Street in Whitburn, turn right on to Armadale Road, then take the second exit onto the A706 at Whitdale Roundabout before joining the A801 at Boghead Roundabout. This will add an estimated two miles and four minutes to affected journeys.
• Eastbound traffic on the A705 will be directed to continue past the turn for the A801 until reaching Toll Roundabout, from where they will be directed to take the first exit onto the A779 Starlaw Road, continuing over two roundabouts before taking the first exit at Boghall Roundabout onto the A7066 Starlaw Road and joining the A801 at Boghead Roundabout. This will add an estimated eight miles and 15 minutes to affected journeys.

Signposted diversions for phase two A801 southbound closures 27 July – 15 Aug

• Traffic on the M8 Eastbound wishing to exit at Junction 4 and join the A801 southbound will be directed to remain on the M8 eastbound and turn at Junction 3A, then at the roundabout take the first exit on to Carnegie Road. At the next roundabout, they will be directed to take the first exit onto Starlaw Road, then take the second exit at the next roundabout heading westbound onto the M8. They can then exit the M8 via the Junction 4 westbound off-slip, where they can join the A801. This diversion will add an estimated six miles and seven minutes to affected journeys.
• Westbound traffic on the A7066 will be directed to take the second exit at Boghead Roundabout onto the A706. Then at Whitdale Roundabout take the first exit onto Armadale Road before turning left on to East main Street. They will then be directed to continue along Main Street until the A801. This diversion will add an estimated two miles and four minutes to affected journeys.
• Eastbound traffic on the A706 will be directed to take the third exit at Boghead Roundabout onto the A7066 Starlaw Road. Then take the fifth exit at Boghall Roundabout onto Starlaw Road, continuing over three roundabouts before taking the third exit at Toll roundabout onto the A706 and continuing along until the A801. This diversion will add an estimated eight miles and 15 minutes to affected journeys.

In advance of these works consultation has taken place with relevant stakeholders, including close liaison with West Lothian Council.

David Bishop, BEAR Scotland’s South East Unit Bridges Manager, said: “This programme of concrete investigation works is key to ensuring the structural integrity of these bridges which were built in 1970 and form part of Scotland’s busiest motorway. It is our responsibility to monitor and ensure their service life for years to come.

“The works have been planned to minimise disruption to road users as far as possible which is why they’re being done overnight. However, we appreciate this is a key junction and therefore some disruption should be expected. Full closures of the northbound side and southbound sections of the roundabout are unavoidable in the interests of the safety of motorists and our workforce.

“We thank road users in advance for their patience and understanding while we carry out these essential works and would ask them to fully comply with traffic restrictions to ensure our workers can go home safely to their families each day.”

Live traffic information is available from the Traffic Scotland website www.traffic.gov.scot and on X at @trafficscotland.

All work are weather dependent and subject to postponement or cancellation in the event of adverse conditions.