Cymraeg icon Cymraeg

Essential road works to take place on M4

Gwaith ffordd hanfodol i'w wneud ar yr M4

Motorists are advised to plan ahead before they travel in the coming months as a series of major road works and lane closures are set to begin on two separate sections of the M4 this summer.

The road works between junctions 47 and 49 will take place from August to December. There will also be diversions in place between junctions 24 and 28 on the eastern side of the Brynglas tunnels in September.

Both projects involve essential maintenance work to ensure the longer term resilience of the road network and to avoid any unplanned emergency repairs. The work will involve the re-waterproofing, resurfacing and replacement of bridge joints to several bridge decks. Work is taking place during the summer period to minimise the likelihood of delays to the work caused by adverse weather conditions.

During the works between junctions 47 and 49, the traffic management layout will change to accommodate each phase of the scheme with traffic running in contraflow using the hard shoulder from early September until mid-November. Lower, mandatory speed limits will also be in place to protect drivers and the workforce delivering the scheme.

To accommodate works between junction 24-28 a four-weekend and eight-night work programme has been put in place involving full carriageway closures, avoiding simultaneous closure of the eastbound and westbound carriageway. This could be reduced to two weekends and eight nights depending on weather conditions.

Notification of the works including times for contraflow arrangements will be published on Traffic Wales website: Traffic Wales | Traffic Wales

Notes to editors

The roadworks between junctions 47 and 49 will affect Llanelli Bridge, Morlais Loop Line Bridge, Loughor River Bridge and Swansea & District Line Bridge. The works between junctions 24 and 28 will affect the Usk Bridge.

The dates earmarked to carry out works between junction 24-28 include:

  • 7th-16th August (weeknights only)
  • 8th to 11th September 2023
  • 15th -18th September 2023
  • 22nd – 25th September 2023
  • 6th - 9th October 2023