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Tickenham to Portishead
Current construction activity
Date from | Date to | Activity |
June 2021 | Late 2024 | |
May 2021 | 2024 | |
January 2020 | September 2021 | |
2018 | Ongoing |
Overview – Autumn 2022
In July 2022, we started work to build the northern section of the Hinkley connection between Sandford and Seabank substations.
We’re building 68 new T-pylons for part of the route between Sandford and Portbury, and new traditional lattice pylons through Avonmouth to make the final connection into Seabank substation.
By using the innovative T-pylon design, the height of the new infrastructure is being reduced by a third. Standing at around 35 metres high – the T-pylon is third shorter than traditional 400,000 volt steel lattice pylons which stand at around 48 metres. It also has a smaller footprint and uses less land.
To make for and reduce the visual impact of the new pylons, National Grid is removing 67 kilometres of existing 132,000 volt lattice pylons and overhead wires, a total of 249 pylons will go from the Somerset landscape.
So far, we’ve removed a line of lattice pylons between Nailsea and Portishead, 37 kilometres of pylons between Bridgwater and Sandford, and a short section from across the M49 near Avonmouth. Programme for removal in 2023, is the eight pylons closest to Sandford substation, and the long line that runs from Sandford to Avonmouth.
Thank you from everyone working on the project for your patience and understanding as we progress this vital work to connect six million homes and businesses to new sources of homegrown, low carbon energy.
Contact our community relations team to register for project updates direct to your inbox.
Tickenham to Portishead timeline
Early 2020 to mid 2021
Underground the 132,000 volt overhead line between Nailsea and Portishead Substation
What we're doing:
Building 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.
Building temporary construction compounds.
Building a 132,000 volt underground cable between Nailsea and Portishead Substation.
Building a new CSE pylon to connect the existing overhead line at Nailsea to the new underground cables.
This new underground cable section is being 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 2025
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 2025
Remove existing 132,000 volt overhead line
What we're doing:
Removing approximately 9 km of Western Power Distribution’s (WPDs) 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 WPDs 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 2025
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.
This work will be done on our behalf by WPD.