Jellyfish Swarm Shuts Down French Nuclear Reactors

Three reactors at France's large Gravelines nuclear power plant, located in northern France, were shut down late on Monday. The shutdown was a precautionary measure initiated due to a significant swarm of jellyfish in the cooling canal connected to the North Sea. Reactors 2, 3, and 4 were completely taken offline, while reactor 1 was limited to 50% output as a safeguard. Reactor 5 was already undergoing maintenance, and reactor 6 remained operational.

These preventative actions were enhanced following an entire plant outage last year, which prompted operator EDF to develop new strategies. These include fixed cameras for early detection of blockages and partnerships with fishing and sea rescue organizations. These partners monitor for jellyfish swarms and can deploy targeted trawling operations to reduce their density before they reach the plant.

Fishing boats were deployed recently after an initial alarm, successfully limiting the swarm's impact. On-site jellyfish are being removed using vacuum trucks. EDF anticipates a quick restart of the affected units as no new jellyfish are arriving. The company assures that the situation poses no risk to safety, personnel, or the environment. Scientists suggest such events may increase due to climate change and other environmental factors.