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Traffic Wales information line 0300 123 1213
The Welsh Government’s traffic information service for motorways and trunk roads in Wales

M4 J48 and A4138 Junction Improvement


Where and Why?

Improvement works will commence on 12/04/2021 at Junction 48 of the M4. The majority of works will take place on the junction slip roads and the adjoining A4138 county road.  The completed scheme will provide increased capacity through the junction as well as enhancing the existing pedestrian facilities.

The construction works are anticipated to take 9-12 months to complete.

Diversions and Safety Measures

Total closures of the slip roads at junction 48 will be required for short periods as work progresses. The dates of these closures will be signed 7 days in advance at the site and will be publicised on the Traffic Wales website. The diversion route for the slip road closures will be to continue to the next junction and return along the opposite carriageway.

Programme of traffic management restrictions

Traffic management will be present at the site from the scheme commencement with any road closures to be notified by information signs at the site, 7 days in advance of being implemented. 


For further information, please contact Traffic Wales on 0300 123 1213 or via Twitter @TrafficWalesS

Call the Traffic Wales information line
0300 123 1213
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