M4 westbound closure near Swindon as £20 million repair work continues

Drivers travelling through Wiltshire are being warned of overnight disruption on the M4, with a section of the motorway between Junction 16 and Junction 17 scheduled to close as part of a major £20 million repair programme.

The westbound carriageway between Junction 16, near Swindon, and Junction 17, near Chippenham, is due to close overnight on Saturday 14 November and Sunday 15 November, between 8pm and 6am.

The work is part of a National Highways scheme to repair and strengthen the motorway infrastructure, including sections of the embankment, drainage systems and safety barriers.

Drivers are being advised to plan their journeys in advance and allow additional time when travelling through the area.

National Highways has confirmed that the closure and subsequent traffic restrictions are needed to allow engineers to carry out essential repairs safely.

The project includes stabilising a 600-metre section of embankment affected by ground movement, repairing four bridge decks and replacing safety barriers in the central reservation.

Following the overnight closure, longer-term restrictions will remain in place on the westbound carriageway between Junctions 16 and 17. The hard shoulder and lane one are scheduled to remain closed until 17 February 2027, with a 50mph speed limit in operation.

Eastbound drivers will continue to have access to all three lanes during this phase of the work.

During overnight closures, signed diversion routes will direct motorists through Wootton Bassett and Chippenham. National Highways has specifically advised drivers to follow the official diversion signs rather than relying solely on satellite navigation systems.

The wider improvement scheme is expected to continue until spring 2028, representing a £20 million investment in maintaining the safety and reliability of an important transport route connecting Wiltshire with the South West and the wider motorway network.

Drivers travelling between Salisbury, Swindon, Chippenham and other parts of the region are encouraged to check the latest traffic information before setting off.

The dates and arrangements for road closures may change, and motorists should check for updates before travelling.

Official updates: National Highways: M4 Junctions 16 to 17 improvement works