
National Grid to commence essential upgrade work on overhead electricity line between Bodelwyddan and Connah’s Quay
National Grid is commencing work to upgrade 30 kilometres of overhead electricity transmission line in North Wales, between Connah’s Quay substation in Flintshire and Bodelwyddan substation in Denbighshire.
The project is part of a series of circuit upgrades taking place across the country which aim to speed up connections to the electricity transmission network and support a secure, affordable and clean energy system. The project does not involve replacing, moving or building any new pylons.
The work demonstrates National Grid’s continued investment in its network across Wales, with £3.2bn of investment planned between 2026-2031 to maintain, upgrade and develop the network.
To carry out these essential upgrades, the A55 in North Wales will be temporarily closed overnight between Junctions 31 and 32A on four dates later this year.
The four overnight closures are:
Closure 1 – from 9:30pm on Monday 14 July, to 5:30am on Tuesday 15 July
Closure 2 – from 9:30pm on Wednesday 3 September, to 5:30am Thursday 4 September
Closure 3 – from 9:30pm on Monday 6 October, to 5:30am Tuesday 7 October
Closure 4 – from 9:30pm on Monday 27 October, to 5:30am Tuesday 28 October
The highway will be closed in both directions during these periods, and a temporary diversion route will direct traffic along the A5026.
The temporary closures are needed where National Grid’s overhead line crosses over the A55 between these junctions.
The closures have been closely coordinated with the North and Mid Wales Trunk Road Agent, as the organisation responsible for the highway.
National Grid’s work will involve putting up two scaffold structures either side of the A55, and netting over the carriageway. This method, commonly used to safely replace wires crossing over roads, means the highway can remain open by day during the work. By taking this approach, and closing the road only at night, National Grid is seeking to minimise the effects of its work on road users and local people.
James Heywood, Project Manager at National Grid Electricity Transmission, said:
We’ve worked hard to try and minimise any disruption for road users, and we appreciate the cooperation and understanding of the community as we carry out these essential upgrades. Our Connah’s Quay to Bodelwyddan refurbishment project is an important part of our work to maintain the reliability of our electricity network and connect low carbon energy in the region.
Preparatory work to upgrade the lines began in September 2024, with the main phase of the works commencing in July 2025. The components on overhead lines are designed to last up to 60 years. They are now nearing the end of their operational life and need replacing to maintain the reliability of the electricity network.
National Grid is expecting to complete all works on the project in December 2026.
For more information about National Grid’s project to replace overhead wires between Connah’s Quay and Bodelwyddan, visit https://www.nationalgrid.com/electricity-transmission/network-and-infrastructure/infrastructure-projects/connahs-quay-bodelwyddan#English