Tickenham to Portishead
Current construction activity
| Date from | Date to | Activity |
| May 2021 | 2024 | Building and energising new T-pylons |
| 2020 | 2024 | Removing existing pylons |
| 2018 | Ongoing | Roadworks and traffic management |
| 2018 | Ongoing | Access to public footpaths and rights of way |
Overview – Autumn 2024
National Grid is moving into the final stage for completing the northern section of the Hinkley Connection route between Sandford and Seabank substations.
The removal of 15 lattice pylons and construction of two T-pylons within Portbury Wharf Nature Reserve give visitors a new view. Partnership working with North Somerset Council, including the Reserve Warden, is ongoing to ensure agreed works to return the land are carried out to the Council’s satisfaction and to avoid disturbing local wildlife.
The main works currently in this area is the removal of construction accesses, temporary roads, and work areas built to construct the new overhead line. You may notice more construction traffic on local roads. We will keep you informed about any required traffic management updates in advance.
The construction of 68 new T-pylons between Sandford substation and Portbury, including the hanging of the wires is complete. Using the T-pylon design reduces the height of the new infrastructure by a third. At 35 metres high they are shorter than National Grid's traditional lattice transmission pylons and take up less room on the land.
To make way for the new 400,000 volt connection, National Grid has removed 249 lower voltage lattice pylons, and overhead wires stretching 67 kilometres from the Somerset landscape.
Thank you from everyone working on the project for your patience and understanding as we work to toward completion. This project will play a key role in helping the UK meet its net zero ambitions by transmitting cleaner, homegrown, energy around the UK – enough to power six million homes and businesses.
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Tickenham to Portishead timeline
Completed mid 2021
Undergrounding the 132,000 volt overhead line between Nailsea and Portishead Substation
This work has been completed.
Work carried out:
Built temporary entrances and access roads to allow construction traffic to enter site from the local highway. You can find more information on our construction information page.
Built temporary construction compounds.
Built a 132,000 volt underground cable between Nailsea and Portishead Substation.
Built a new CSE pylon to connect the existing overhead line at Nailsea to the new underground cables.
This new underground cable section has been built as a direct result of feedback received during our consultation. It will enable us to completely remove the existing 132,000 volt overhead line that currently runs very close to people’s properties.
Mid 2021 to mid 2024
Build new 400,000 volt overhead line
What we're doing:
In this area, to minimise disruption, we will be sharing temporary construction compounds, and temporary entrances and access roads built for other elements of the build.
Building a new 400,000 volt overhead line from Sandford Substation to Seabank Substation (approximately 31.2km).
We will use T-pylons in this area.
Mid 2021 to mid 2024
Remove existing 132,000 volt overhead line
What we're doing:
Removing approximately 9 km of existing overhead line between Nailsea and Portishead substation that currently runs very close to people’s properties. We are removing this as a direct result of feedback received during our consultation.
Removing overhead line from the A368 in Sandford to Avonmouth, which will make way for, and minimise the visual impact of the new connection.
Early 2021 to mid 2024
Modify Portishead Substation and the overhead line to the east of the substation
What we're doing:
Making changes to the inside of Portishead Substation to enable the connection of the new 132,000 volt underground cable from Nailsea.
Building a temporary construction compound to the east of the substation.
Building temporary entrances and access roads to allow construction traffic to enter the undergrounding site from the local highway. You can find more information on our construction information page.
Removing a section of 132,000 volt overhead line to the east of the substation and replacing it with underground cable. This will enable the 400,000 volt overhead line to pass safely overhead.
Installing a Cable Sealing End (CSE) pylon to connect the new underground cable to the existing overhead line.