Hungary has begun shutting down one of the four reactor units at the Paks Nuclear Power Plant after the Danube reached exceptionally low water levels, highlighting the growing impact of the country’s prolonged heatwave and severe drought.

The operator, MVM Paks Nuclear Power Plant Ltd., announced on Wednesday afternoon that the shutdown of Unit 3 began at 3 PM as the Danube continued to fall to record-low levels along several sections of the river.

According to the company, the water level at Paks had dropped to -118 centimetres, prompting the decision to take the reactor offline in line with operational and environmental safety requirements.

Plant operators said they are continuously monitoring river flow and water temperature and will make further operational decisions based on changing conditions. The company stressed that maintaining the plant’s safe operation while complying with environmental regulations remains its top priority.

Emergency measures in place to secure cooling water

Earlier on Wednesday, Environment Minister László Gajdos announced that Hungary’s water management authority had entered a state of heightened readiness to ensure a continuous cooling water supply for the nuclear power station despite the extreme drought.

In a Facebook post, the minister said authorities have already deployed four floating pumping units and two floating cranes on the Danube near Paks. Although pumping is not yet necessary, 55 specialists are working around the clock on standby to respond if conditions deteriorate.

“The protective measures are ongoing. We are safeguarding Hungary’s water resources and national security,” Gajdos wrote.

Output had already been reduced

The shutdown follows several days of gradually reducing the plant’s electricity output as the Danube’s water level continued to decline.

Economy and Energy Minister István Kapitány previously described the power reductions as a planned precautionary measure rather than a technical fault, emphasising that they are carried out under pre-established operational rules.

He also warned that another heatwave is expected to sweep across Europe in the coming days, likely increasing electricity demand while causing the Danube’s water level to fall even further.

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Extreme heat and drought continue to affect Hungary

According to MVM, the combination of persistent drought and extreme summer temperatures has significantly reduced the Danube’s flow this year.

Environmental regulations limit the temperature of the cooling water discharged back into the river after passing through the reactors. To remain within these limits, the plant has already had to reduce the output of its reactor units on several occasions during June and July.

Meanwhile, the Danube has reached historic lows in Budapest as well. On Tuesday morning, the river gauge measured just 30 centimetres, before falling even further later in the day, according to Telex.

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