**Motorists in South Wales Advised of Major Road Closures on M4, A470, A40 and A48 This Week**
Road users across south Wales are being urged to plan ahead as a series of planned overnight road closures are set to affect major routes including the M4, A470, A40, and A48 in the coming week. Essential works ranging from maintenance and resurfacing to structural inspections are being carried out, with both drivers and local residents likely to feel the impact of diversions and potential delays.
The M4 motorway, a vital artery for Welsh transport, will experience multiple closures across different stretches, with work concentrated between east and west Wales. Key locations such as the Prince of Wales Bridge, Baglan, Llandarcy, and Llangyfelach are among those targeted for scheduled intervention. Motorists should be particularly mindful that most closures will begin at 8pm and last until approximately 6am, minimising daytime disruption but presenting significant overnight detours.
For those prone to travelling on the M4 at night, the forthcoming week will see Wenallt Road Overbridge closed for structural checks from 8pm on 19 May to 5am on 20 May, with diversions provided. Elsewhere, the Prince of Wales Bridge and the stretch from Pilning to Rogiet are scheduled to shut for maintenance nightly from 19 to 22 May between 9pm and 6am. Additional closures include the Grove Park to Tredegar Park tunnel (20–22 May) and slip roads at Baglan, Llandarcy, and Llangyfelach, where electrical works require both entry and exit restrictions across a series of nights.
Meanwhile, the A470 will undergo phased closures between Upper Boat, Nantgarw, and Pontypridd for cyclic maintenance works. Southbound lanes will be affected between Upper Boat and Nantgarw on the night of 18–19 May. The northbound route from Upper Boat to Pontypridd will close nightly from 19–21 May, and the reverse direction southbound will be shut from 21–23 May. Temporary traffic lights are also in use at the Abercynon Roundabout until mid-June, which could lead to further delays during overnight hours.
Further north, drivers using the stretch between Betws-y-Coed and Llanrwst are advised to expect slow-moving traffic due to improvement works and the implementation of temporary signals up until the end of June. The ongoing project seeks to enhance the safety and reliability of this key route.
The A40 is not without its own interruptions, as resurfacing work between Raglan and Abergavenny is expected to result in full closures overnight. The eastbound section from Raglan to Abergavenny’s Hardwick Roundabout will be affected until 20 May, while the westbound carriageway undergoes similar treatment overnight on 20–21 May. Further along, the route from Wolf’s Castle to Letterston continues to operate with a single lane and alternating ‘STOP/GO’ signs during the day as improvement works continue until early June.
On the A48, carriageway maintenance has necessitated the closure of the bridge between Briton Ferry and the A483 junction from 8pm to 6am until mid-June. Diversions are in place to guide drivers around the affected area during these periods.
Travel experts recommend motorists check for the latest updates before setting out, especially if journeys are planned overnight. The ongoing works are vital for maintaining the safety and performance of Wales’ busy road network, but authorities acknowledge the inconvenience they may cause for those travelling during the scheduled closures.
A spokesperson for the highways agency noted that while overnight works have been chosen to lessen daytime disruption, some impact on journeys is inevitable. They further advise drivers to follow posted diversions carefully and remain alert for any temporary traffic management measures.
Continued investment in Wales’ infrastructure remains a priority, as evidenced by this flurry of maintenance and improvement projects. In the meantime, affected travellers are encouraged to stay informed via official channels and allow extra time for overnight journeys through the region’s main routes.