Future access
Ensuring suitable vehicle access routes to the new Hinkley Connection infrastructure
Future access requirements
National Grid Electricity Transmission (NGET) is the owner of the high voltage electricity transmission network in England and Wales. We are responsible for maintaining that network and delivering electricity safely, reliably and efficiently to communities.
We’re making significant investments to upgrade the electricity transmission network. Our infrastructure projects are helping to connect more clean, affordable energy to homes and businesses across England and Wales and the Hinkley Connection Project (legally referred to as the Hinkley Point C Connection Project) is a key part of that.
The Hinkley Connection Project comprises new overhead electricity lines and pylons, including new T-pylons, two new substations and 8.5km of underground cables under the Mendip Hills. Construction started in 2018.
As construction works have progressed, National Grid has been able to further its knowledge and understanding of the maintenance requirements for the newly built infrastructure. This has led to the identification of locations along the Hinkley Connection Project where the planned permanent vehicle access routes to the new infrastructure are no longer suitable for maintenance and emergency access in the future because they cannot accommodate the vehicles we now know we need.
To secure suitable permanent vehicle access routes, we need to seek changes to the Hinkley Point C Connection Project Development Consent Order (DCO) which was granted in 2016 by the Secretary of State giving planning consent for the Hinkley Connection Project to be built.
A Development Consent Order (DCO) grants planning consent for major infrastructure development where it is categorised as a Nationally Significant Infrastructure Project (NSIP).
Applications relating to energy NSIPs are submitted to the Planning Inspectorate, which appoints an Examining Authority to consider the application and thereafter make a recommendation to the Secretary of State for Energy Security and Net Zero, who is responsible for determining whether or not to approve the application. DCOs differ from a normal planning application, which is determined by the relevant local authority.
National Grid Electricity Transmission (NGET) secured planning consent for the Hinkley Point C Connection Project in 2016. As an NSIP, this was secured via a DCO. Construction works began in 2018 and the project is expected to be completed by the end of 2026.
To seek these changes we need to submit a DCO material change application to the Secretary of State. We are in the process of preparing that application and more information can be found below.
The procedures for making a change to an existing Development Consent Order (DCO) are set out within the 2008 Planning Act and associated secondary legislation.
As detailed in the UK Government’s guidance on infrastructure projects (2011), the nature of large scale Nationally Significant Infrastructure Projects (NSIPs) like the Hinkley Connection Project means “it is likely that changes will be needed either before construction of the project begins or during the construction process. Where such changes are not covered by the DCO that has been granted for the project, an application needs to be made for a formal change to the DCO.”
There are two types of changes that can be applied for: non-material or material. A change is considered material if, for example, it requires an updated Environmental Statement or it would authorise compulsory acquisition of land. The Hinkley Connection Project material change application will involve both.
Hinkley Point C Connection Project – DCO material change application
National Grid is to seek changes to its 2016 DCO, including the associated land rights, by submitting a material change application to the Secretary of State.
The changes are to ensure suitable future access to the new electricity transmission infrastructure built as part of the Project by:
- securing permission to retain a number of structures that were constructed by National Grid but intended to be temporary
- securing permission to upgrade and use those structures and additional existing structures that belong to landowners
The combination of a change in land rights, which will involve seeking compulsory acquisition powers where these cannot be agreed, and the ability to upgrade then retain these structures permanently will ensure we can access the new infrastructure as efficiently and safely as possible along the route.
We are working closely with landowners to reach agreements where possible, before our application is submitted.
Please click here to visit the project-dedicated webpage of the Planning Inspectorate’s website for the Hinkley Point C Connection Project material change. This page provides information about our material change application, including project documents and more information on the application process and timeline.
Structures subject to the material change application
Most of the structures we are seeking to retain and upgrade, then use for access are culverts that enable vehicle access over waterways. Our application is also likely to include other means of vehicle access, including gateways and junctions, short sections of access roads and a small number of T-pylon work pads.
Culverts are access structures designed to allow water to continue flow under roads, railways, embankments, or other infrastructure. They are installed to allow vehicles to cross bodies of water.
Work pads are a levelled and prepared surface that provides a stable foundation for equipment, machinery, or temporary structures required for construction or maintenance work. Work pads are constructed to support heavy loads, ensure safety, and facilitate efficient operations during construction or the operational maintenance of T-pylons.
Anticipated impact of the DCO material change
Local landowners along the route would be the most directly affected by the proposed changes and we’re working closely with them on our proposals. This includes reviewing all access and design options, including the type, number and location of the structures required to ensure suitable future vehicle access.
If the DCO material change application is granted, some landowners will host permanent access structures on their land for future use by National Grid, which were previously scheduled for removal as part of the 2016 DCO.
Where we are seeking a change to land rights, we are working with landowners to secure those changes by agreement. Where agreement cannot be reached, we will seek compulsory acquisition powers as part of the DCO material change application.
We do not anticipate any significant wider community impacts arising from the proposals outlined within the material change application. The proposals will be the subject of Environmental Impact Assessment (EIA) and an EIA Scoping Report will be submitted to the Planning Inspectorate shortly. This will identify the potential for any significant environmental effects related to the proposals.
Any additional individuals or groups set to be directly affected by our proposals will be invited to provide feedback on the plans as part of the consultation process. Our consultation is currently planned for Autumn 2025.
Further information
As construction works have progressed, National Grid has been able to further its knowledge and understanding of the maintenance requirements for the newly built infrastructure.
This has led to the identification of locations along the Hinkley Connection Project where the planned permanent vehicle access routes are no longer suitable for maintenance and emergency access in the future.
The main reason for this relates to the maintenance requirements of the new T-pylons, which require larger Mobile Elevated Work Platforms (MEWPs), cranes and vehicles than we originally assumed. This means that some of the authorised permanent access routes cannot accommodate the vehicles and equipment required.
Permanent vehicle access arrangements to other newly built infrastructure including Cable Sealing End compounds, where overhead electricity lines connect to underground cables near the M5 at Loxton and Horsey, and some of the new traditional pylons in Avonmouth is also no longer suitable.
To secure suitable permanent vehicle access routes to newly built infrastructure along the Hinkley Connection Project route, National Grid is seeking changes to the 2016 DCO through a material change application to the Planning Inspectorate.
The Hinkley Connection Project features T-pylons, the first new design for a pylon in Great Britain in nearly 100 years. Following stakeholder feedback including feedback received as part of statutory consultation, in May 2011, The Royal Institute of British Architects in partnership with the Department for Energy and Climate Change together with National Grid launched an international competition to find an alternative design to the traditional lattice pylon. Danish architect Bystrup proposed the winning concept design, which has a single pole and T-shaped cross arms that hold the overhead conductors from two diamond-shaped insulators. National Grid worked with Bystrup to develop the final design.
At approximately 35 metres tall, the T-pylons constructed along the route of the Hinkley Connection Project are approximately a third shorter than traditional lattice transmission pylons and have a much smaller footprint on the land.
Our practical experience of constructing the Project has given us a much clearer understanding of the maintenance requirements for the T-pylon. In particular we now know that to navigate the terrain in which the Project is situated, we will require larger MEWPs, cranes and vehicles than originally assumed for maintenance and emergency access.
Securing these permanent vehicle access routes will ensure we can access the new infrastructure as efficiently and safely as possible along the route with the vehicles and equipment that would be required for maintenance and emergency purposes.
We are expecting to start our statutory consultation in Autumn 2025. Following this, we will review the feedback submitted, finalise our plans and submit our material change application to the Planning Inspectorate in 2026. The Secretary of State for Energy Security and Net Zero will then decide whether to approve the application for a material change.
Yes, individuals or groups set to be directly affected by our proposals, as well as relevant statutory consultees, will be invited to provide feedback on the plans as part of the consultation process. Further information will also be shared online as part of our statutory consultation due to take place in Autumn 2025.