What is Hinkley Point C doing?
Hinkley Point C is making applications to relevant regulators to remove the requirement to install an acoustic fish deterrent (AFD) system. Requirements relating to the deterrent are set out in the Hinkley Point C Development Consent Order (DCO), water discharge activity environmental permit and marine license. Three separate applications will be needed:
- DCO: Application to the Secretary of State for a material change to the DCO
- Environmental Permit variation: Application to the Environment Agency
- Marine Licence variation: Application to the Marine Management Organisation
What is an acoustic fish deterrent?
The deterrent uses sound to deter certain groups of fish (i.e. those with well-developed hearing) from the cooling water intakes. Only sprat and herring of the most common fish in the Bristol Channel have good hearing and they are abundant and not commercially fished. The deterrent is less effective for fish with less developed hearing and ineffective for some species.
What does the new study show?
Hinkley Point C commissioned an environmental study from the Government’s independent expert body, the Centre for Environment, Fisheries and Aquaculture Science. It evaluated new and previous data to consider the impacts on fish species assuming the deterrent is removed. This work concludes that the power station would have negligible impacts on fish stocks.
The worst case predicted effect of Hinkley Point C with the planned 2 fish protection measures varies by species from a maximum of 0.2% to less than 0.001% per year.
The impact of the power station is tiny in comparison to the impact of commercial fishing.
Why did EDF Energy propose the system in the first place?
It was regarded as emerging best practice when the plans were drafted. Now that more detailed design has been undertaken Hinkley Point C has concluded that the deterrent does not provide significant benefit and that its installation and on-going maintenance poses unacceptable safety risks to divers and workers.
Why did you commission the study?
Hinkley Point C wanted to understand the impact of the power station on fish stocks without an acoustic fish deterrent. We knew that there was new data available six years on from the planning application. We believe in a science-based approach and asked Cefas to look at the science to assess the impact of the power station.
What is the danger to workers?
Further detailed design work has concluded that the safety risk to workers is unacceptable to the Hinkley Point C project – especially given the minimal benefit provided by the acoustic fish deterrent.
Visibility in the muddy water is zero, tidal flow peaks at around 1.8 metres per second and tidal height varies by more than 10 metres between low and high tide. Maintenance by divers is really only achievable around slack water for 30 minutes.
The system would be extremely complex to construct and maintain with offshore operations restricted to narrow tidal windows and subject to lengthy periods of interruption by weather. The fish recovery and return system and low velocity side entrance intake head structure have been successfully incorporated into the design and will be built.
What fish protection measures will be built?
Hinkley Point C will be the first power station in the Bristol Channel to have fish protection measures. The cooling water system includes low velocity side entry water intakes designed to minimise the number of fish taken into the system and a fish return system.
The Hinkley Point C cooling water intake system will take seawater direct from Bristol Channel before returning that same water back into the sea. Water will be taken through intake heads and tunnels 3.3km from the shore at a depth of 20m below the seabed. Four intake heads and two tunnels are proposed. Once at the shore the water will go through a filtration system of coarse and fine mesh screens in a cooling water pumphouse. Fish will be returned to the sea via a fish return system.
Will all fish survive going through the cooling pipes?
All power station cooling systems using river or sea water have an impact on fish. Even with measures to protect fish, not all will survive the passage through the cooling tunnels. The fish return system is effective for more robust species.
The total amount of fish taken will be around 56 tonnes compared with 650,000 tonnes commercially fished in the UK each year by over 6,000 boats. So our impact will be equivalent to about a small trawler's catch per year.
What fish live in the Bristol Channel?
Typically, there are between seven and ten species that make up 95% of the fish found around Hinkley Point: European sprat, herring, whiting, sole, cod, thin-lipped grey mullet, flounder and 5 bearded rockling. Of these species only sprat and herring have good hearing, the others have average to poor hearing and are therefore less likely to respond to sound deterrents. Twenty fish species were included in the comprehensive assessment undertaken by Cefas.
What about salmon and sea trout?
These migratory species do use the Severn Estuary but primarily use the main channel of the estuary they also swim near to the surface. They are not expected to be affected in any significant numbers as the future intakes are about 10km from the main channel and are near the bottom.
Do any other power stations use acoustic fish deterrents?
There are examples of AFD systems being used at UK power stations, there are no examples of such a system being installed in an offshore environment or in conditions as harsh as those encountered in the Bristol Channel.
What is a material change to a Development Consent Order?
There is no set definition of what constitutes a material or non-material change although there is some Government guidance on suggested circumstances. We intend to submit an update to the Environmental Impact Assessment and updated information to inform a Habitats Regulations Assessment focusing on the removal of the AFD. This will be based on updated information and data since the DCO in 2013. As these assessments are being prepared to be submitted, we are adopting a precautionary approach by treating the change as material.
An application for a material change is decided by the Secretary of State for Business, Energy and Industrial Strategy.
Who did you consult with?
Hinkley Point C has an independently chaired Marine Technical Forum, made up of the Environment Agency, Marine Management Organisation, Natural England, Natural Resource Wales and the Devon & Severn Inshore Fisheries Conservation Authority.
There was a pre-application consultation period in which statutory and non-statutory consultees were consulted. Notices were published in appropriate newspapers, Lloyds List, London Gazette and relevant fishing journals. The Environment Agency and the Marine Management Organisation are carrying out separate consultations on our respective applications to them.
What is the process once an application has been submitted?
Once an application has been made we will notify consultees and publish notice of the application. There will then be a 28-day period within which representations can be made to the Secretary of State. The Secretary of State will consider whether to hold an examination prior to determination of the application and will take all relevant representations into account prior to making any decision.