Coastal erosion raises questions over protection for £40bn Sizewell C nuclear plant

The accelerating pace of coastal erosion after a damaging winter on the UK’s east coast has raised fresh questions over protection for a new £40bn nuclear plant under construction.

19 March 26, https://www.itv.com/news/anglia/2026-03-19/coastal-erosion-raises-questions-over-protection-for-40bn-nuclear-plant

Sizewell C is being built on the Suffolk coast, near the site of two previous nuclear power plants, with an operational and decomissioning timeline stretching for more than 100 years.

But a bruising winter along the coast, which has seen dozens of homes demolished before they fall into the sea, has led to concerns about the wisdom of building the plant on one of the fastest-eroding coastlines in Europe.

Sizewell C said the plant would be built on a “more stable section of the coast between two hard points” and an offshore bank of sediment known as the the Sizewell-Dunwich Bank.

Prof Sir David King, chair of the Climate Crisis Advisory Group, said a secure future for Sizewell lay in adaptable and robust defences.

“The question is no longer should it be built there, because it is being built; but rather ‘How do we protect it?’”, he said.

“I would be constructing a wall around Sizewell B and Sizewell C, and I would see the foundations for this wall going in quite soon.

“Build the foundations now so that in later years, as sea levels rise, we can build them all up to defend appropriately,” he advised.

The plans are for Sizewell C to be built on a platform approximately 7m above today’s sea level.

It will be protected by a sea defence structure more than 14m above today’s sea level, which will take the form of temporary sheet-pile sea defences during construction and will be replaced by permanent structures throughout the plant’s operational lifetime and decommissioning until 2140.

Sizewell C said the plant would be built on a stretch of coastline which had been shown by data to be “comparatively stable”, while the beach will also be enlarged and maintained to form a soft coastal defence.

It adds that it will all be adaptable, meaning if sea levels rise beyond predictions, so too can the defences.

But communities along the coast complain there is an inequality of defence.

While millions are being pumped into defences at Sizewell, others living elsewhere along the coast are being left to fend for themselves and there is a big debate on whether what happens at Sizewell will have an impact on neighbouring areas further down the line.

The campaign group Together Against Sizewell C believes planning approval should not have been granted without Sizewell C demonstrating it had a viable plan to protect the site from an extreme climate change scenario.

Chris Wilson from the group said: “Why was the modelling for flood-risk in the [development consent order] restricted to a site lifetime of 2140 when it was clearly evident that spent fuel would be on site beyond that date?”

“And why was it allowed to be based on an unchanging coastal geomorphology assuming that the protective sand bars… would remain intact throughout the full lifetime of the project?”

There have also been concerns raised about how the defence work to protect Sizewell C will impact further down the coast.

Local resident Jenny Kirtley said erosion had escalated in the past year “far more than anybody thought it would”.

“A worry will be when they start the work out at sea,” she said.

“There will be two jetties built and huge intake and outfall tunnels built under the seabed. We know what’s happened to Thorpeness already. Is this going to make to make it more difficult for Thorpeness? Will these sea defences cause more problems?”

The answers are inconclusive.

Robert Nicholls, professor of coastal adaptation at the University of East Anglia, has studied the coastline for many years.

“The effects of Sizewell become significant if we are forced to protect it”, he said.

“At the current time, Sizewell doesn’t need much protection. So probably I would argue it’s not having a huge effect on its neighbouring coasts, if it suddenly began to erode and you had to protect it, then it might start to have a big effect both on the coast to the north and the south.”

At the village of Thorpeness, 11 families have already lost their clifftop homes to erosion in the last few months.

Residents have been given permission to take matters into their own hands and are raising hundreds of thousands of pounds to place rock bags at the bottom of what is left of the sandy cliff.

But with millions being pumped into defences for Sizewell C, residents want support from the project to help secure their future too.

Dennis Skinner from the Thorpeness Community Interest Company said: “The scientists can do all the studies but, as we’ve seen in the last two months with the amount of erosion here in Thorpeness, I don’t think anyone can be certain about what impact different things are having up and down the coastline

“Sizewell C have got a budget in excess of £50bn, so contributing to Thorpeness will just be a rounding sort of figure.”

A spokesperson from Sizewell C told ITV News Anglia it was monitoring local coastal processes and the situation at Thorpeness.

“We’ve performed thousands of hours of flood risk modelling using the highest plausible estimates for sea level rise and therefore have the highest level of confidence that Sizewell C is in the right location,” they said.

“It’s located on a more stable section of the coast and […] drones are regularly producing 3D maps of changes, coastal erosion, and accretion […] If there are any unexpected developments, we will take action to address them.

“Our assessments show that the power station will be built to withstand a 1-in-10,000-year storm and 1-in-100,000-year surge”.

Roger Hawkins is desperately trying to save his house at Thorpeness from the inevitable erosion.

“We recognise that it’s impossible to defend the whole coast, and there are some areas where you’ve got areas of dense population like towns and docks and infrastructure like Sizewell C, where you can obviously need to have a hard defence.

“But at what point do you stop providing the hard defence?”