National Highways has shared a diversion route that has been put in place as the M4 motorway is closed in both directions this evening (March 6) due to a serious crash. The incident was first reported at around 8.30pm, between J17 for Stanton St Quinton, and J18 for Bath. Initially, just the westbound carriageway was closed, before the motorway was then closed on both sides.
Emergency services are at the scene, with Wiltshire Police leading the response. And now, National Highways has shared an extensive diversion route for drivers travelling between the two junctions – which will take motorists more than 13 miles south of the motorway.
Posting on their website this evening, National Highways wrote: “The M4 westbound in Wiltshire is closed in both directions J17 (Stanton St Quinton) and J18 (Bath), due to two serious collisions. Emergency services including Wiltshire Police are in attendance. National Highways Traffic Officers are also on scene to assist with traffic management.”
Diversion route
Road users travelling westbound are advised to follow the solid diamond diversion symbol on road signs, and take the following route:
- Leave the M4 at J17 and at the roundabout take the 2nd exit onto the A350.
- Continue on the A350 to the roundabout with the A420 at Chippenham and take the 3rd exit onto the A420.
- Proceed on the A420 to the roundabout with the A46 at Cold Ashton and take the 3rd exit onto the A46 heading north.
- Follow the A46 back to the M4 J18 and rejoin the M4 westbound to continue your journey.
Road users travelling eastbound are advised to follow the solid square diversion symbol on road signs, and take the following route:
- Leave the M4 at J18 and take the 3rd exit onto the A46 heading south.
- Follow the A46 to the roundabout with the A420 at Cold Ashton and take the 1st exit onto the A420 heading east.
- Continue on the A420 to the roundabout with the A350 at Chippenham and take the 1st exit onto the A350.
- Proceed on the A350 back to the M4 J17 and rejoin the M4 eastbound to continue your journey.
National Highways added: “If this closure impacts on your planned route, please allow extra journey time. Plan ahead, you may wish to re-route or even delay your journey.”
Meanwhile, traffic monitoring Inrix reports another crash nearby: “All traffic being temporarily held and long delays due to accident on M4 in both directions from J16 A3182 Hay Lane (Swindon West) to J17 A350 (Chippenham).
“Traffic was held at around 21:20. Two separate collisions at this location.”
For live updates from the scene, follow our live blog here.