Hinkley Point C plan could save 90% of fish drawn into intake pipes.

Study finds an underwater acoustic system at Hinkley Point C could deter about 90% of fish from its cooling water intakes and save roughly 44 tonnes of fish a year.

Hinkley Point C plans to use an underwater acoustic deterrent to steer migratory fish away from its cooling water intakes. Scientists at Swansea University tested the system in trials commissioned by EDF Energy and reported strong avoidance by tagged fish. EDF says the system could prevent about 90% of fish being drawn into the intake pipes and estimates it would cost about £700m. The company also says it will absorb the cost under its subsidy contract. Key findings: - Swansea University tested an acoustic system that uses more than 300 underwater speakers to emit sound pulses around intake heads. - Trials with tagged twaite shad showed one fish came within 30 metres of the test intake when the system was on, compared with 14 when it was off; researchers described a majority avoiding a roughly 60‑metre zone around protected intake heads. - The research estimates the system could save about 90% of fish taken by the intakes, equivalent to about 44 tonnes a year. - EDF estimates the deterrent would cost about £700m, roughly 1.5% of the project’s £46bn build cost, and said it would absorb that expense rather than add it to household bills. - The planned measures include special intake mouths to slow suction, and a fish recovery system to return fish taken into the pipes; tagged salmon were rarely detected near the intakes across two years of monitoring. - Results will be submitted to the Marine Management Organisation for regulatory consideration and approval later this year. Summary: The research indicates an acoustic deterrent could substantially reduce fish being drawn into Hinkley Point C's cooling intakes and is reported to save about 44 tonnes of fish each year. EDF estimates the system would cost about £700m and says it will absorb the expense under its subsidy contract. The research results will be submitted to the Marine Management Organisation for regulatory consideration later this year.