We want to improve safety and traffic flow on junctions around Newport.

First published:
2 December 2016
Last updated:

For traffic news visit Traffic Wales.


Project status: Planned
Region/county: south east - Newport
Start date: spring 2015
End date: 2018
Cost: £13.7m
Design and Build contractors: Costain/Arup

This project has been registered with the Considerate Constructors Scheme (external link)

Why we are doing it

We want to reduce delays on the M4 and encourage more traffic to use the southern distributor road. We are also making the roundabouts easier to use.

The plan

Tredegar Park roundabout

We are planning to add traffic lights and enlarge the south roundabout and build a route through the roundabout.

Bassaleg roundabout

We are improving traffic capacity through the roundabout and adding traffic lights.

Southern distributor road and Pont Ebbw roundabout

We are planning to build a road through the roundabout that joins the   southern distributor road to the A48.


Invitation to tender: summer 2014
Award contract: winter 2015
Approve preliminary design: summer 2016
Approve detailed design: winter 2016
Begin construction: spring 2017
Completion date:  autumn 2018
End of defect correction period: winter 2019

Current progress

New lane arrangements, traffic signals and sections are due to open this month.

Familiarise yourself with the changes we’ve made with the maps below.

How we consulted

We consulted as part of the M4 Corridor Enhancement Measures consultations.


You can find out about road closures, diversions, and project news by subscribing to Costain’s mailing list.

Email our public liaison officer Hannah Lewis to subscribe, or call 0845 6002664.