Danube River Hits Record Lows and Threatens Romania, Hungary Nuclear Plants
The green excavator scooped another heap of arid dirt and rocks before swiveling around to deposit the load onto barges ready to be sunk deep into the Danube River. Watched by a group of workers in the scorching Romanian heat, it was the latest stage in a complex engineering operation with a specific goal: to gain 10 centimeters.
With its water level at a record low, the shrunken Danube is disrupting trade and tourist cruises and making locals along its banks from Bratislava to Belgrade confront the impact of climate change. But upriver from Romania’s only nuclear power plant, raising that water level by a few inches is now mission critical to maintaining electricity supplies.
The week started with blasting a rock formation on the river with nearly 400 pounds of explosives. That added a much needed few centimeters to avert a full shutdown of the Cernavoda plant. The next step is to sink the loaded barges on Wednesday in an attempt to raise the Danube further and push the water down river toward the nuclear facility.
Read more: Rhine Falls to Lowest Since 1880, Threatening European Trade
“These works should have been done a long time ago,” said Ion Marin, one of the excavator handlers at the site. “But like everything in this country we only do works when there’s an emergency.”
While the Rhine is more critical to Europe as an industrial supply line, the Danube is a lifeblood to communities in the 10 countries it either passes through or for which it forms a national border. Four capitals — Vienna, Bratislava, Budapest and Belgrade — sit on it and the river provides drinking water to about 10 million people.
Economically, Europe’s longest inland waterway after the Volga carried 62.7 million tons of cargo in 2025, equivalent to the maritime port of Amsterdam. It also helps cool nuclear power plants, vital to the energy mix in the region when other resources get stretched.
At Hungary’s reactors on the Danube, engineers were watching the water level minute by minute. In the control room, the chief engineer of the overnight shift was within a millimeter of giving the order to switch off the last remaining turbine of a plant which, when running at full capacity, contributes 40% of Hungary’s electricity supply.
But then the Danube’s waters started rising, by a significant 5 centimeters, according to Prime Minister Peter Magyar. “It was a huge stroke of luck,” said Tamas Cseh, member of parliament for the town of Paks, where the plant is based.
The running turbine is cooled from waters sucked from the Danube. The town derives its hot water from it. Even more significantly, restarting the whole plant once water levels recover will be easier if one turbine is still turning, experts said. A full shutdown, which could yet come, would be the first in the facility’s 44-year operating history.
One of the problems is that the Soviet-era technology didn’t cater to the now drier climate and subsequent governments didn’t make the necessary changes, Cseh said. The Danube’s water, lapping against cracked earth that just weeks before was the riverbed, would still be sufficient to cool the reactors had the pump inlets sucking up the water been set deeper below the surface.
“Everyone knew this would happen sooner or later,” Cseh said. “Now it just has to rain.”
In the meantime, Hungary’s parliament on the bank of the Danube in Budapest is empty after sessions were delayed to save energy. Decorative lighting in the city as well as those of state-owned buildings have been turned off. Under one of the bridges linking the Buda and Pest sides of the city, the ruins of an earlier bridge, destroyed in World War II, are visible just below the surface.
Voluntary cutbacks from carmakers and battery plants have also alleviated some of the pressure on the grid, as have auto companies in neighboring Romania.
Upriver in Bratislava, the effects of a shrinking Danube were also visible. More than a dozen vessels are now moored in the Slovak capital, waiting for rain and the water level to rise to allow passage up to Vienna or down to Budapest.
A popular tourist route for leisure and travel cruises, 610,000 passengers were transported on the Upper Danube lines in 2024, according to the most recent data from the Budapest-based Danube Commission.
“We were joking that we are actually not on a river cruise but on a houseboat,” said Lou, a tourist from Florida. “We just come here to sleep on a boat. We’re gonna make the most of it. It’s great, but the river is low and it’s too sad.”
It’s too early to calculate the impact, according to economists. So far, much of the assessment is anecdotal, whether on the Danube or the Rhine. In the Swiss port of Basel, for example, truck drivers and cargo handlers said some shipments are having to be driven partly by road.
The Danube remains navigable, though many cargo ships are taking reduced loads because of the depth of the water. Ukraine has rerouted some grain shipments to use the Danube after Russian attacks on its Black Sea ports.
What is clear is that it’s bad timing for a country like Romania. Its economy is expected to stagnate at best in the second half of the year, industrial production is in a prolonged decline, inflation remains high and there’s only an interim government with limited powers in place after months of political instability.
The low water levels have also prompted governments in Bucharest and Budapest to ask citizens to curb consumption, a tough demand for farmers at the peak of the season growing staples such as tomatoes and peppers.
“The Danube drought will not derail Romania’s economy, but an economy already in stagnation has very little room for avoidable shocks,” Valentin Tataru, chief economist for Romania at Dutch bank ING, said in a report.
Temperatures that climbed to 41 degrees Celsius (106 Fahrenheit) around Romania on Tuesday are expected to stay high for the rest of the week. They’re complicating the Danube operation and putting further pressure on power consumption needs across the country of 19 million.
There’s no choice than to try, though. Romanian Deputy Energy Minister Cristian Busoi said without the intervention the nuclear plant’s second reactor would also have to be shut down.
“I’ve lived here all my life and this is the worst drying up of the river I’ve ever seen,” said Maria Galita, 56, who was selling fruit at the side of the road near where the Danube forms the border with Bulgaria and where the authorities were trying to get the water level up.
Some rain is forecast in Austria for this week, but it remains to be seen if it will be enough. Temperatures across mainland Europe are forecast to be 2C to 8C warmer than normal through early August. Longer-term weather models support more rounds of high pressure, which may mean little drought-busting rainfall until later in the year.
Romanians like Galita say they’re used to seeing sand islands in the middle of the Danube during summer, but there was never the need to intervene to keep the nuclear plant cool.
The appearance of sand, meanwhile, was more welcome in Belgrade, landlocked Serbia’s capital. The receded water level gave locals a surprise extra shoreline to cool off in the heatwave. An island where the Danube and the Sava rivers merge now offers a larger beach.
“This is incredible,” said Marko Tesanovic, 51, sunbathing on a section normally under water. “If the Danube drops any further, people will be able to walk across to the other bank.”
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