Lane closure expected between Junction 16 and Junction 17 until May
Safety improvements and maintenance work will start on the M4 near Chippenham next week.
The work, between Junction 16 and Junction 17, will continue until May, and includes the stabilisation of embankments, upgrading of traffic signals, and replaceing sections of the steel central reservation with concrete barriers.
The new concrete barriers are said to reduce the risk of vehicles involved in accidents crossing from one side of the motorway to the other and to improve the safety of road users and road workers.
They are also unlikely to require repairs after vehicle impact.
Rachel Scott, of the Highways Agency, said: “The work has been careful planned so we can undertake more than one scheme at the same time which will significantly reduce disruption.
“However I would advise people to plan their journeys and allow extra time.”
The programme starts on Monday, January 28 and continues until May.
The work will require a hard shoulder and lane one closure until Easter when all restrictions will be lifted for the holiday period.
A 50mph speed limit will also be in place to ensure the safety of road users and worker.
Further work being undertaken during this time will be drainage repairs and fence replacement.