Drivers facing 60 mile diversion as major road closes for two weeks

Nation Cymru staff

A major south Wales road is set to close overnight for two weeks from next week, with communities each side of the works facing a detour of up to 60 miles if following the official diversion routes.

Works have been scheduled to carry out essential concrete testing to inform future repairs to A465 Clydach Gorge Viaduct from next week.

During this time a series of night time closures (20:00 – 06:00) of the A465 Westbound from Glanbaiden roundabout to Brynmawr roundabout will be in place.

Works will commence on 16/11/2026 for 2 weeks, and drivers have been urged to prepare for any inconveniences ahead of the road closure.

Concrete testing is required on A465 Clydach Gorge Viaduct to inform the design of future concrete repairs.

The works will take place over a series of night time closures (20:00 – 06:00) of the A465 Westbound from Glanbaiden roundabout to Brynmawr roundabout.

Many locals and communities either side of the works have shared their anger about the disruption the closures will cause which have been echoed by a local MS.

Member of the Senedd for Sir Fynwy Torfaen, Peter Fox MS, has called for ‘urgent’ clarity over the state of the road from the Welsh Government.

He commented: “When I first raised this matter, I asked Welsh Government whether a full assessment of the route had been undertaken. We now learn that further concrete testing is required on the viaduct, causing significant disruption for motorists.”

“Welsh Government must be transparent about what is being investigated, what defects have been identified, and whether similar concerns exist elsewhere on the scheme.”

“This section of the A465 was already delivered years late, over budget and has experienced a number of issues since opening. Local people will understandably want reassurance that all necessary checks are being carried out and that any emerging problems are being addressed quickly.”

“Motorists and residents deserve clear answers, and I have written to the Cabinet Secretary seeking further information about the works, their purpose and any future repairs that may be required.”

More information can be found here.