Sizewell C will not have a significant effect on fish populations. Sea water is needed to operate the cooling system of the power station, but a fish return system and specially designed heads on the sea intake pipes will minimise the impact on fish. Government scientists at CEFAS say there is no scientific evidence that the rates of impingement at Sizewell C will have a significant effect on population sizes. Fish populations produce vast numbers of young each year. The species which will be most affected by the power station will be sprat and herring but the losses are expected to be just 0.01% of the adult population each year. That’s a tiny fraction of the population size and of the natural variation in the numbers of adult fish from year to year.