M4 eastbound closure for final stages of smart motorway work

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

A stretch of the M4 is shutting for the final stages of upgrade work to turn it into a smart motorway.

The motorway will close eastbound, between junctions 12 for Theale and 11 for Reading, from 22:00 BST on Saturday until 06:00 on Monday.

Highways England said it included work on the bridge that carries the M4 over the River Kennet. 

Traffic will be diverted via the A4 and A33 with drivers warned to allow extra time.

Throughout the day on Saturday one lane will remain closed eastbound between junctions 12 and 11 - the other three lanes will be open all day.

• What are smart motorways and are they dangerous?

• How smart are smart motorways?

Work to widen the motorway to four lanes between junction 3 at Hayes and junction 12 at Theale started in 2018. A 32-mile (52km) stretch reopened in July.

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.