THE new permanent 50mph speed limit on the M4 around Newport will go live in less than two weeks.

The permanent limit between junction 24 for Coldra and junction 28 for Tredegar Park, which will be enforced with average speed cameras, will begin on Monday, March 15,

The measure forms part of the Welsh Government’s approach to tackling congestion in the area as recommended by Lord Burns’ report published following the work carried out by the South East Wales Traffic Commission. The group was set up after the M4 relief road was scrapped in 2019.

Over the next couple of weeks work will be undertaken to finalise the installation of the cameras and road signs.

There will be night-time full closures of the eastbound carriageway this week, followed by westbound full closures next week, commencing March 8, from 8pm to 6am.

Additional information about diversion routes and any disruption to the travelling public can be found on the Traffic Wales website and twitter.

The cameras will be operational and the mandatory 50mph speed limit will be monitored closely by Go Safe during the bedding-in period.

It will allow for full systems and enforcement checks to take place and give motorists time to get used to the new speed limit.

Notices of prosecution will then begin to be issued in the summer.

Mark Travis, assistant chief constable of South Wales Police said the limit was needed due to a number of collisions on the stretch of road.

He added: “I welcome the introduction of a permanent reduced limit and corresponding Average Speed Camera scheme to ensure compliance on this section of the M4 and to reduce death on Welsh roads.

"The Welsh Government and four Welsh police forces are committed to working in partnership to maximise the amount of safe and efficient journeys our residents and visitors make on our roads.

"Safe roads are vital to the wellbeing of our communities, in particular young people, it is right that we make our communities as safe as they can be.”

The change is intended to:

  • Help manage congestion issues along this stretch of the M4;
  • Improve journey times and provide smoother traffic flows;
  • Reduce the risk of accidents;
  • Improve air quality by reducing emission levels.


Ken Skates, minister for economy, transport and North Wales, said: “This work shows this government’s commitment to tackling congestion in the region.

"We are doing this in the context of the climate emergency and our clear objective of reducing emissions from the transport sector.

“The South East Wales Transport Commission produced a number of recommendations to tackle congestion which we were happy to endorse.

"Transport for Wales’ Development Unit is now tasked with supporting us to take forward Lord Burns’ wider recommendations forward and we will continue to work with partners to improve journeys in the area.”

GoSafe partnership manager, Teresa Ciano added: “GoSafe is committed to supporting our highways authority partners to ensure that the speed limits on our roads are adhered to.

"There are many benefits to a reduced speed limit on this section of road and vehicles utilising the road should see road safety and journey improvements.

"We will review the traffic after the changes and are prepared to enforce the speed limit if necessary.”