National Grid has confirmed that preparatory activity is due to begin on the Cilfynydd to Melksham 400kV overhead power line, which has been in service for around 60 years and now requires refurbishment to ensure continued safe and reliable electricity transmission. The wider programme forms part of The Great Grid Upgrade, the largest overhaul of the national electricity network in generations.

📍 Route Section Relevant to South Gloucestershire

The full refurbishment route runs from the north‑east of Llanbradach, through south Newport, across the Severn Estuary and South Gloucestershire, to Melksham. This update covers the section between Llanbradach and South Gloucestershire, including the crossing of the Severn Estuary.

🛠️ Preparatory Works (October 2026 – March 2027)

National Grid will begin enabling works ahead of the main refurbishment programme, which is expected to start in summer 2027. Preparatory activity includes:

• Vegetation clearance from 6 October 2026 to March 2027, ranging from light trimming to cutting back larger trees and hedges to allow safe access to pylons and overhead lines.
• Ground investigation surveys along the route.
• Access improvements near certain pylons, including upgrading existing tracks, minor ground works, and drainage improvements.
• Temporary closures of footpaths and Public Rights of Way (PROW) where required for safety. Residents and representatives will be notified in advance of any closures.

National Grid will contact affected landowners before work begins and will secure all necessary permissions.

🔌 Electricity Supply

The company has confirmed that electricity supplies will not be affected during any stage of the works.

👥 Resident Communication

Residents and businesses close to areas of significant activity will receive advance notification and ongoing updates. Timings may change due to weather or site conditions; National Grid will provide updates if the programme is amended.

ℹ️ Further Information

A route map, project details and updates are available on National Grid’s website. For enquiries, contact the Community Relations team: Telephone: 0800 188 4478 Email: cilfynyddtomelksham@nationalgrid.com