Status: Accepted for Examination 26th September 2025 Planning Inspectorate Reference Number EN020027

Notification of decision to accept application (Link to acceptance letter)

Link to The Planning Inspectors website to access documents and view updates on the examination: Documents | Norwich to Tilbury

The proposals are for a new 400kV electricity overhead transmission line in East Anglia running from Norwich (National Grid’s Norwich Main substation) to Tilbury in Essex.

They will also need to carry out some work at existing substations along the proposed route and build a new substation in the Tendring district to connect new offshore wind projects close to the coast.

The reinforcement in South Norfolk will consist of new overhead lines supported by a standard steel lattice pylons of 50metres in height with a distance of 350 metres between the pylons. It will start at Norwich Main substation, running to the west of the district, crossing the River Waveney into Suffolk.

The Project is a proposal by National Grid to upgrade the electricity transmission system in East Anglia between Norwich and Tilbury. The Project includes a new 400 kilovolt (“kV”) electricity transmission connection of approximately 184 kilometres ("km”) in overall length from Norwich Main Substation and Tilbury Substation via Bramford Substation, comprising:

• approximately 159 km of new overhead line supported on approximately 510 steel lattice pylons (approximately 50 metres (“m”) in height) some of which are gantries (typically up to 15 m in height) within proposed Cable Sealing End (“CSE”) compounds, or existing or proposed substations
• approximately 25 km of 400 kV underground cabling some of which is located through the Dedham Vale National Landscape (formerly known as Dedham Vale AONB)
• six new CSE compounds, each with a permanent access, to connect the overhead lines to the underground cables
• a new 400 kV East Anglia Connection Node (“EACN”) substation, with a new permanent access, on the Tendring Peninsula. This is proposed to be an Air Insulated Switchgear (“AIS”) substation
• substation extension works at the existing Norwich Main, and Bramford substations and works within the existing Tilbury Substation to connect and support operation of the new transmission connection
• temporary works associated with construction of the Project

For the avoidance of doubt, the alternative design at the Waveney Valley (referred to as the Waveney Valley Alternative) is not being proposed and does not form part of the Project.

Link to the developer’s website: Norwich to Tilbury | National Grid

Link to the National Grid ESO East Anglia Study: East Anglia study | National Energy System Operator

Link to view South Norfolk District Council’s Pre-Application submissions : 2022/1116 | National Grid - New overhead power line between Norwich and Tilbury | Norwich To Tilbury