M4 Hayes-Theale: Smart motorway reopening under way

The £848m project to turn the M4 into a smart motorway started in 2018

A 32-mile (52km) stretch of the M4 is reopening following a £848m upgrade to turn it into a smart motorway.

Work to widen the motorway to four lanes between junction 3 at Hayes and junction 12 at Theale started in 2018.

The stretch between junctions 3 at Hayes and 8/9 for Maidenhead is being cleared of roadworks - junctions 8/9 and 12 opened in December.

National Highways said cones and barriers would be lifted by 06:00 BST on 16 July.

But it added a 60mph limit would remain in place while final testing on smart motorway technology, including stopped vehicle detection, takes place.

A free recovery service will also stay for now.

• What are smart motorways and are they dangerous?

• How smart are smart motorways?

During the removal of the cones and barriers, over several nights, the motorway will be closed in sections until 15 July from 21:00-06:00.

Smart motorways use a range of new technology, including electronic signs, to vary speed limits in response to driving conditions.

In January, the government paused the rollout of smart motorways amid safety concerns until five years' worth of data has been collected to assess whether or not they are safe for drivers.