Our site at Hurst is located at the junction of the A223 and Stable Lane in North Cray. We will be building a permanent headhouse at our Hurst site, to drive a tunnel boring machine to our reception site at Crayford and receive a tunnel boring machine from our existing substation site at Eltham. Excavated material will also be removed at this site.

We are building the tunnels and shafts under our permitted development rights, which means we do not need planning permission for the entire project. We have secured planning permission for the headhouse from the London Borough of Bexley. The headhouse is required for ventilation and as a permanent point of access for the tunnel once it is built.

Key milestones achieved at Hurst

National Grid has been working on the site since February 2021 and since this time we have:

  • launched our Tunnel Boring Machine, Christine, from Hurst

  • completed 2km of the Tunnel Boring in January 2022 with 4.7km remaining.

Working hours

  • Our working hours at Hurst are 24/7 and night-time works are limited to removing material from the shaft and lowering segments into the shaft for the tunnel. There will be no HGV movements during the night shift.

Key facts

  • Dimensions: The shaft will be approximately 15m in diameter and 35m in depth. The headhouse will have a maximum footprint of 15m long by 15m wide and will reach a maximum height of 10m.

  • Traffic movements: We anticipate there will be approximately 64 HGV movements per day while we build the tunnel to Eltham, and 58 HGV movements per day at peak times while we build the tunnel to Crayford.

  • Access: Our construction vehicles will leave the site using our temporary access road which will connect the A223 North Cray Road to Stable Lane. Following feedback from our public information events in 2018, National Grid constructed this access road for all HGV traffic to re-direct vehicles away from residential roads.


  • The tunnel from Hurst to Crayford is due to be completed in April 2023.

  • The tunnel from Hurst to Eltham is also due to be completed in April 2023.

  • The headhouse is scheduled to be built between May 2023 and April 2024.

  • Once works have been completed we will remove the temporary access road and return the land to its original condition. This is planned to be completed by 2026.

Field worker inside london power tunnels

Contact us

If you would like to discuss the project in greater detail or have any questions, please contact our community relations team using the details below:

Call our Freephone helpline number: 0800 783 2855 (lines open 9am to 5pm, Monday to Friday)

Email: [email protected]