Campaigners warn coastal erosion could threaten Sizewell C site
The group argues that building a nuclear power station in the area poses long-term flood risks.
Last updated 13th Jan 2026
Campaign group Together Against Sizewell C (TASC) has raised renewed concerns about coastal erosion near the Sizewell C construction site, following recent storm damage along the East Anglian coastline.
TASC spokesperson Chris Wilson said the group believes the Sizewell coastline is among the fastest eroding in Europe and argues that building a nuclear power station in the area poses long-term flood risks.
“How long can government continue to ignore nature’s warnings, expecting future generations to clear up the mess from ill-thought-out decisions made today?” Mr Wilson said.
Coastal erosion
Recent storms have led to homes being demolished at Hemsby and Thorpeness, prompting concerns about wider coastal vulnerability.
Mr Wilson said: “Witnessing the recent rapid erosion of the East Anglian coastline, with homes being demolished at Hemsby and Thorpeness, is heartbreaking.”
He added that the Sizewell C site itself is already experiencing erosion, saying that dunes fronting the site appeared to be breached and overtopped earlier this month.
TASC argues that the Sizewell C project, as approved under its Development Consent Order (DCO), does not demonstrate how the site would remain protected from flooding under a “credible maximum sea level rise scenario” throughout its full operational lifetime.
According to the group, additional sea defences may be required in future, which they say were not assessed as part of the original planning application. TASC claims the potential need for further defences was known to the developer prior to the submission of the DCO application but not included for public scrutiny.
Mr Wilson said the group had raised the issue with the Secretary of State in March 2025, adding that their request for further assessment was refused. He said this left TASC with “no alternative but to pursue the matter through the courts”.
Future risks
Speaking in an interview, Mr Wilson said: “The biggest concern for the Sizewell site generally has been the risk of flooding it. The coastline’s recognised as one of the fastest eroding coastlines in Europe.”
He added: “We’ve always said that building a new nuclear power station on the Sizewell C site is not a good idea, and the recent events with homes being demolished at Thorpeness and Hemsby are indicative of how volatile and vulnerable the coastline is.”
Mr Wilson also raised concerns about how future sea defences could affect surrounding areas, saying hard defences could divert erosion elsewhere along the coast.
He said TASC wants greater transparency from the developer, adding: “I think they should publish the results of additional seabed surveys and be open and transparent about how Sizewell C will be protected for its full lifetime, right up to the late 2100s.”
The group says it is awaiting the written judgment following a recent court case, after which it will decide whether to appeal.
Responses
A Sizewell C spokesperson said: “Assessments, carried out as part of our Development Consent Order, suggest Sizewell C will not affect Thorpeness or any other part of the Suffolk coastline.
- “We’re putting robust measures in place to prevent any impacts on coastal processes, and we’ll closely monitor the coastline.
- “Many thousands of hours have gone into assessing future flood risk at Sizewell, including flood risk arising from climate change, and our plans will ensure the power station is protected, even in extreme scenarios.
Background
- Sizewell is located on a stable section of land, between two hard points and the offshore bank of sediment known as the ‘Dunwich – Sizewell Bank’.
- Sizewell C will be built on a platform standing approximately 7 metres above today’s mean sea level and will be protected by a sea defence structure which will be more than 14 metres above mean sea level.
- The sea defence will be adaptable and could be raised in future if sea level rise turns out to be greater than current predictions.
- The sea defence will be adaptable and could be raised in future if sea level rise turns out to be greater than current predictions.
- Assessments show that the power station and access road will be built to withstand a 1-in-10,000-year storm and 1-in-100,000-year surge events.
In a statement, a Department for Energy Security and Net Zero (DESNZ) spokesperson said:
“We are reversing a legacy of no new nuclear power being delivered to unlock a golden age of nuclear, securing thousands of good, skilled jobs and billions in investment.
“Sizewell C will deliver clean electricity for the equivalent of six million of today’s households for at least six decades, and once operational, it could save £2 billion a year across the future low-carbon electricity system, resulting in cheaper power for consumers.”
The government said development consent for Sizewell C was granted on 20 July 2022 after consideration of all relevant information. The reasons for the decision are set out in the Secretary of State’s decision letter, published alongside the Planning Inspectorate’s Recommendation Report.