Europe’s Key Rivers Are Drying Up as Extreme Heat Impact Widens

(Bloomberg) — Europe’s biggest rivers, vital arteries for the region’s heavy industries, are drying up after the region was seared by a series of heat waves.

As water levels in the Rhine and Danube fall toward record lows, that’s starting to disrupt the transport of chemicals, oil products and other goods, while boosting freight costs. Soaring temperatures are also curbing power generation at riverside reactors from France to Hungary, pushing up energy prices and straining Eastern European economies.

Following the wildfires that ravaged France and Spain, it’s another sign of how climate change is taking its toll on the fastest-warming continent. The river disruptions are becoming a test of how quickly the region can adapt infrastructure built around 20th-century conditions to a climate where extreme low water is likely to be increasingly common.

“Human-induced warming has already made this drought more severe than it would otherwise have been, and the same rainfall deficit would give a worse drought again under further warming,” said Dominik Schumacher, a lecturer in the Department of Environmental Systems Science at ETH Zurich.

Water levels at Kaub, a key chokepoint on the Rhine for shipments heading to southern Germany and Switzerland, have fallen to 25 centimeters earlier on Friday, matching the low reached during a drought in 2018.

A drop to 24 centimeters, which is forecast this week, would mark the lowest level since records began in 1880, according to German federal data compiled by ETH Zurich.

With the fourth heat wave to grip Western Europe this summer stretching through most of this week, the situation risks deteriorating, creating logistical bottlenecks on a river that snakes for roughly 800 miles (1,290 kilometers) from the Swiss Alps to the North Sea.

In 2018, BASF was forced to reduce production at its key Ludwigshafen complex in Germany as historically low water levels on the Rhine limited ship access. Now the world’s largest chemicals maker has developed alternative, albeit more expensive, transport options, according to Chief Financial Officer Dirk Elvermann.

“We are, of course, concerned about the issue of low Rhine water levels,” Elvermann told reporters on Wednesday, while adding that the situation was “under control.”

Low Rhine water levels cut German industrial production by as much as 1.5% in 2018, but many firms have since adapted their supply chains, according to Saskia Meuchelböck, a researcher at the Kiel Institute for the World Economy. Inland shipping’s share of Germany’s total freight transport has also dropped from 4.7% in 2017 to 4.1% in 2024.

EnBW, which operates coal-fired power plants supplied via the Rhine, said it’s been building up fuel stocks whenever plants are offline to ensure sufficient inventories. Grosskraftwerk Mannheim said it also has adequate coal reserves, and if water levels fall further, it could reduce cargo loads per vessel, deploy smaller barges or switch some deliveries to rail.

A DB Cargo spokesperson said the railway operator was in constant talks with customers affected by low water levels on the Rhine, Europe’s busiest inland waterway.

Still, even if companies can find alternative supply routes, higher costs threaten to further erode Europe’s industrial competitiveness against rivals in Asia and North America.

“Some inland vessels may no longer be able to operate because of their technical limitations,” said Roberto Spranzi, board member of the German Inland Waterway Transport Cooperative, which represents around 90 ships. High fuel prices, alongside low water levels, were also affecting operations, he added.

Levels in the Rhine and Danube have dwindled over an unusually hot and dry European summer, with repeated bouts of high-pressure blocking moisture-bearing clouds from replenishing watersheds.

The feedback loop has has driven up plant water use, sapping moisture from soils that quickly soak up meager rainfall before it can flow into river basins, said David Hannah, a professor of hydrology at the University of Birmingham.

“Climate change intensifies this by raising baseline temperatures, making hot, dry periods more effective at drying out landscapes and reducing river flows,” Hannah said.

Drought conditions have worsened in central-western Europe in recent weeks, data from the European Commission show. Rhine river levels have also been hurt by reduced snow and glacier runoff from the Alps, which is an especially important source of water in late summer, he said.

Some stretches of the Danube, Europe’s second-longest river, have already fallen to record lows. That’s disrupting barge navigation in Romania and Slovakia, while also hitting output from atomic reactors.

Hungary is fully shutting down its sole nuclear plant for the first time in its 44-year history on Sunday, posing a test for new Prime Minister Peter Magyar. That will strip the country of 40% of its electricity generation capacity, forcing the government to boost power imports.

Hungary’s ruling party has asked parliament to delay its sessions this week to save energy, Magyar said in a Facebook post. Decorative lighting in Budapest as well as those of state-owned buildings will be turned off. In the meantime, voluntary cutbacks from carmakers and battery plants have alleviated some of the pressure on the grid.

Romania’s energy sector will remain on a state of alert through August as power production slumps, and it will ask for support from neighboring Ukraine during peak demand hours. The country may be forced to shut a second reactor at the Cernavoda plant as the low water levels in the Danube impair cooling operations.

This summer’s heat waves have also forced France to curb power output from its nuclear fleet, which forms the backbone of Western Europe’s power system. Power stations draw cooling water from rivers like the Rhone and Garonne, and there’s a risk that as temperatures rise the discharge will get too hot, threatening wildlife.

In the face of the sustained drought, the Hungarian government has appealed for more prudent electricity and water consumption. Demand overload left several thousand people without drinking water in Szentendre, north of the capital.

“If we don’t change, soon we’ll find ourselves in desert-like conditions,” Environment Minister Laszlo Gajdos said on Friday.

Italy’s longest river, the Po, continues to dwindle below historic lows, raising concerns about farm irrigation and saltwater intrusion in its delta.

“The heat and drought definitely represent a new risk to growth,” said Carsten Brzeski, an economist at ING Diba AG. “Dwindling rivers cause real economic pain, plus encapsulate the challenges of climate change.”

Europe’s rivers are unlikely to see major relief anytime soon. Temperatures across the mainland are forecast to be 2C to 8C warmer than normal through early August, according to analysis from Vaisala meteorologist Matthew Dross. Longer-term weather models support more rounds of high pressure, which may mean little drought-busting rainfall until late-fall.

“Significant rain can bring short-term improvements but if dry soils and blocking patterns persist, those gains may be temporary,” Hannah said.

–With assistance from Eamon Akil Farhat, Alberto Brambilla, Irina Vilcu and Andra Timu.

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