Gravelines, one of France's biggest nuclear power stations located between Dunkirk and Calais, was forced to shut down two units on Wednesday and Thursday after jellyfish were found in its seawater filtration system.

The Gravelines nuclear power station is cooled from a canal connected to the North Sea and produces 900 megawatts of power. The company Électricité de France (EDF) said that units three, four and six were now shut due to the jellyfish presence. For related coverage, explore our detailed analysis on Technology and Digital Systems.

Dangerous Situation

Unit three had only been reconnected to the grid on 18 August after the first wave of jellyfish earlier this month, while units one and two were also operating at reduced power as a preventative measure.

The presence of jellyfish in the filtration system posed a danger to the reactor's operation and the safety of the staff.

Measures have been implemented to try to prevent jellyfish infiltration, including a partnership with fishermen who capture and release them further offshore, according to French outlet Ici.

Nuclear Power Plants Affected

This is not the first time that nuclear power plants have faced issues with jellyfish in their cooling systems. Similar incidents have occurred at other nuclear stations, including at the Torness plant in Scotland in 2011 and Sweden's Oskarshamn plant in 2013.

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The company Électricité de France has taken precautions to prevent jellyfish infiltration, including monitoring the seawater filtration system for any signs of jellyfish.

Measures have also been implemented to try to prevent jellyfish from entering the cooling system, including a partnership with fishermen who capture and release them further offshore.

The Gravelines nuclear power plant is cooled from a canal connected to the North Sea A massive influx of jellyfish has led to the partial shutdown of a nuclear reactor in northern France.

Two of Gravelines nuclear power station's six units were shut down on Wednesday and Thursday because of the presence of jellyfish in the seawater filtration system, which is used for cooling, Électricité de France (EDF) stated.

A third unit has been shut down since 10 August due to the same issue, while a fourth has been closed for an inspection.

Gravelines, one of the country's biggest nuclear power stations located between Dunkirk and Calais in the Hauts-de-France region, was also closed last August because of jellyfish in its filters.