Barry Turner, Vice-Chair of BANNG, argues that Bradwell B could have devastating impacts on fish and the marine environment of the Blackwater Estuary in the BANNG column for Regional Life September 2019.
‘It has been described as a giant plughole under the sea, sucking in 130,000 litres of water a second along with vast numbers of fish. The twin inlet tunnels stretching two miles out into the Severn estuary are so big that a double-decker bus could drive through them. The system will cool a new nuclear power station being built at Hinkley Point in Somerset but conservation groups say it will kill up to 250,000 fish a day and must be altered or scrapped. A 5mm mesh will be installed to prevent larger fish being swallowed but the groups, including the Blue Marine Foundation, Wildfowl & Wetlands Trust and Somerset Wildlife Trust, say many fish will be fatally injured when pressed against it. Small fish, eels and the fry of many species, such as salmon, whiting and cod, will be sucked through the mesh and into the cooling system.’
This is an extract from a letter which appeared recently in the national press, relating to predicted consequences from cooling the new nuclear power station being built at Hinkley Point.
View from inside cooling water tunnel workings at Hinkley Point C (EDF Media Library)
All power stations require cooling to dispose of ‘waste’ heat, and the most efficient method is to use huge volumes of seawater.
Fish damage and death will be caused by the mesh screens installed to prevent fish entering the cooling system, but smaller fish, juveniles, eggs, spawn, spat and micro-organisms will pass through the mesh, entering the Hinkley cooling system where they will be subjected to sudden pressure changes, damaging or bursting swim bladders and other organs, sudden temperature changes of tens of degrees, mechanical impacts from pipes and heat exchangers and perhaps exposure to biocides designed to keep the pipework clear of marine growth. After this hideously long 5.3km journey through the cooling system to the discharge point a large plume of heated water and biocides will be spread into the Severn estuary exposing more marine life to damage.
Features can be installed to reduce the numbers of larger fish being killed on screens, but there is little can be done to reduce the consequences for organisms passing on through and these very often cannot survive.
How will the Blackwater Estuary be affected by ‘Bradwell B’ cooling?
The Chinese company promoting the project is having surveys carried out to evaluate use of cooling water taken from and returned to the Blackwater estuary, so there would probably be even worse effects in our more restricted environment.
Oystermen and fishermen reported that the old ‘Bradwell A’ nuclear power station cooling system caused environmental problems in the Blackwater. The seabed was scoured, bleached and barren for a mile and a half both upstream and downstream of the intake and outlet pipes near the Bradwell shore. Seed oysters had to be imported to maintain stocks. After the closure of Bradwell A, the situation began to improve within 18 months.
Bradwell A had a power output of 242 megawatts, while the Bradwell B ‘Hualong 1’is listed as producing 1,070 megawatts, so is four times more powerful. There may also be a second unit making an overall output eight times that of the former station.
Bradwell A needed 1.88 million tons of estuary cooling water per day. I have asked Bradwell B how much cooling water would be required to cool a Hualong 1 reactor and they have agreed to let me know, but unfortunately, no news has arrived at the time of writing. It is safe to assume that it will be considerably more than needed for Bradwell A.
Protect the Natives
In 2013 the Blackwater, Crouch, Roach and Colne Marine Conservation Zone (MCZ) was created with one of its main objectives being the conservation of the Native Oyster and its breeding grounds.
The Essex Native Oyster Restoration Initiative (ENORI) is currently underway and six spat (oyster egg) collector frames have recently been deployed 500m offshore near West Mersea as part of this. The actions of Bradwell B by considering the extraction and return of huge amounts of estuary water in the vicinity of all this work to protect and improve the environment of the Native Oyster beggars belief in its contempt for a precious environment.
Oystermen and fishermen have serious concerns about the impact a larger Bradwell B might have on their industries.
The Environment Agency (EA) says it cannot prevent Bradwell B evaluating the use of the Blackwater to cool the new power station. It can only make a decision when an application for an Environmental Permit is submitted.
Research has shown the Blackwater estuary has a very slow refreshment rate, taking ten days to totally replenish, mainly through tidal movement, and it is unlikely to reliably provide the volumes required. But accessing the wider Thames estuary for sufficient cooling water would mean having gigantic extraction pipes 5 to 7km long. Cooling water access for Bradwell B is fraught with environmental, technical and cost problems. Either of these options would threaten the very survival of the ‘protected’ Colchester Native Oyster and severely damage other marine life and those species dependent on it.
We can only hope the Chinese decide the site is totally unsuitable as a showcase of success, or that our Government recognises the Blackwater is incapable of supporting a new nuclear power station. BANNG will press the EA on these points at a meeting in September.