Beautiful countryside

Environmental Impact

Is Sizewell the right place for a new nuclear power station?

The selection of Sizewell begs many questions, given the very particular features of, for example, highly protected natural habitats, the fragility of the local ecology, and the unpredictable patterns of coastal erosion and flooding. What are the grounds for selecting Sizewell, located as it is in an Area of Outstanding Natural Beauty (AONB) and including Sites of Special Scientific Interest (SSSIs)? (For maps of protected sites close to Sizewell see

Stop Sizewell C lodged three Freedom of Information requests to understand the selection path of the UK’s new nuclear sites. One of these requests revealed that the final decision nominating suitable sites for new nuclear power stations was taken by the Minister for Energy and Climate Change, despite the Government being clearly aware of the considerable threats to the integrity of the European protected Special Protection Areas (SPA) and RAMSAR (wetland conservation) designated sites at Minsmere and Walberswick from the development at Sizewell. The Government will use an Imperative Reason of Overriding Public Interest to put aside the European protection for these important and sensitive sites.

A Habitats Regulations Assessment report from 2010 clearly indicates that other sites close to Sizewell, between Southwold and Woodbridge, are not suitable alternatives as they are internationally designated sites – yet none are SPA or RAMSAR designated sites, as Minsmere is. It lists significant effects for water resource and quality, habitat loss and fragmentation, and air quality on the surrounding European-designated sites.  The report recommends that further assessment, supported by detailed data at project level, is required to determine whether nuclear power development at Sizewell could be undertaken without adversely affecting the integrity of the European sites. What has been the official response to this report?

The EU Habitats Directive requires the UK to report any proposed derogation of European protected sites to the European Commission, which should give its opinion on the proposal within 12 months.

Natural England has raised extensive concerns to EDF about the Sizewell site, and the potential impact not only on Minsmere but also on the East Coast from just south of Lowestoft to the Thames Estuary. Other national and local environmental and council groups have also raised concerns.  What is EDF’s response to these concerns?

The Prime Minister has recently stressed the need to be aware of flood risk as a result of climate change. A recent Defra analysis* states that 12 of Britain’s 19 civil nuclear sites are at risk of flooding and coastal erosion because of climate change. Sizewell is said to have a high risk of flooding. Is EDF sufficiently aware of these risks? And what is the Prime Minister’s response? 

What will be the impact on our fragile coastline? (With thanks to the Minsmere Levels Stakeholders Group ) 

Long-shore drift and coastal surges: The Suffolk coast has always been exposed to considerable erosion by the North Sea, as evidenced by the destruction of the prosperous port of Dunwich between the 12th and 16th century, but major floods more recently include those of 1938 and 1953, 2006, 2007 and 2013, when storm surges flooded Dingle marshes – and Minsmere.

In Suffolk, the waves strike the coast at an angle, moving the sand and shingle along the beach, in a southerly direction, (also called long-shore drift). Whereas the Sizewell A & B sites are built up on harder ground, the Sizewell C site and surrounding area inland, to the west of the power station site, is low and liable to flood. In the longer term, as sea levels continue to rise, the power station site will become an island. North-east winds will blow the sea directly onto the site, unprotected by any beach shingle and with greater force as the off-shore protective banks become less effective in moderating the waves.

Currently storm surges are modified by the Dunwich and Sizewell Banks. These protect the shore at Minsmere and Sizewell from storm surges, and reduce long-shore drift. The banks are moving with time and have reduced and separated over the past 150 years and, coupled with sea-level rise, this will reduce their protection of the shore further. Initial plans for a very large loading platform, up to 1,500m long, protruding over the inshore sandbank of piled construction has been rejected by EDF due to its predicted effect on long-shore drift to the south where several erosion hotspots are already causing concern. EDF is still proposing the use of a beach landing facility for large indivisible loads but there are unanswered questions regarding the effects that this and the currently inadequate hard coastal defence will have both to the north and south of the Sizewell C site. Further modelling of these structures and their effects on the coast along with coastal breaches induced by storm surges that will become more frequent with global warming and sea level rise is required.

The Shoreline Management Plan (SMP) 2010 review of the East Anglian coast identified a range of strategies, defined as: ‘Hold the line’, ‘managed retreat’, or ‘no active intervention’. The latest version of this plan shows that the Minsmere Sluice (the outlet for the New Cut, a cut channel for the Minsmere river) is rated ‘hold the line’, but the shingle banks to north and south are ‘managed retreat’. In 2012/13 the Environment Agency completed major repairs to the Minsmere Sluice, and to the sluices on the New Cut. Until recently (consultation 3) EDF has repeatedly stated that it has no concerns or interest in the coastline both north and south of the Sizewell frontage, although the withdrawal of the jetty proposal was made partly on the predicted effect on long-shore drift to the south. Similarly, the continued viability of the Minsmere Sluice is not of interest to EDF although the impact of the beach landing facility and incomplete hard coastal defence has yet to be properly evaluated.

The discharge of rainwater from the Sizewell site, with large areas of hard standing, is also of concern. The natural consequences of increased rainfall, rising sea levels through climate change will accelerate the point at which the existing gravity-fed sluice will no longer be able to handle the volume of discharge. Alternative solutions, including the permanent installation of pumped discharge, must be examined, and funding plans prepared.

We require assurances that EDF will recognise its responsibility to make a major contribution towards such mitigation. We also need to know a great deal more about the projected impact of the development on the Minsmere coastline, both during the construction phase and also over the lifetime of the station.

Power Station Construction and Long Term Access proposals for a causeway and culvert crossing of the Sizewell Marsh SSSI, where the Leiston and Sizewell Drains currently join Minsmere South Levels en-route to the Minsmere Sluice, will seriously hamper groundwater transfer between Sizewell Marsh and Minsmere Levels. From visual observation of water flows in these two drains at the Sizewell marsh exit, it is clear that much of the inland hydrology at this point is via groundwater transfer and the compression introduced by a causeway and culvert crossing will adversely impact Sizewell Marsh, making it a wetter environment and Minsmere South Levels a dryer environment by reducing groundwater levels within the marsh.


Nuclear risk: The Fukushima accident in 2011 in Japan, following the major tsunami, and the continuing problems of temporary cooling water storage, highlight the need for nuclear power stations to be prepared for extreme events, and also to be able to cope satisfactorily with multiple failures.  Whilst Dr Mike Weightman, chief inspector, Office of Nuclear Regulation, commented that the Eastern UK was not exposed to any tsunami risk, experience over the last ten centuries shows that extreme weather conditions do occur, and 99 percent certainty is not enough, given the 150-year expected existence of the power station on site.

* see also  and