Low Danube water levels challenge refineries but supply holds

Low water levels on the Danube River are forcing refineries along Europe's second-longest waterway to shift petroleum product shipments to rail and other transport methods, but companies said supply chains remain largely intact despite barge capacity constraints that have cut river transport volumes by more than half in some areas.

Barges on the Danube are now operating at 30%-40% of normal capacity in Serbian stretches, according to Serbia's energy minister, Dubravka Đedović Handanović, who said July 28 that the country achieved only about a quarter of planned petroleum product imports in July.

The Danube, which flows through 10 countries including Germany, Austria, Slovakia, Hungary, Serbia, Romania and Bulgaria before emptying into the Black Sea, is a critical transport artery for petroleum products, grains and other commodities across Central and Southeast Europe.

But the low Danube water levels' impact on refinery operations remains limited as facilities, including Slovakia's 122,000 b/d Slovnaft Bratislava and Austria's 192,000 b/d OMV Schwechat, near Vienna, have activated alternative transport networks.

Slovnaft said the Danube flow at Komárno, about 100 km southeast of Bratislava, fell to around 39% of normal levels in July, cutting planned river transport volumes by half.

"Although the Danube water flow has dropped significantly and we are currently able to transport only about half of the planned volumes by river, the situation does not pose a major risk to us," Slovnaft told Platts, part of S&P Global Energy, adding that its refinery network allows quick replacement of river transport with other options to keep fuel supplies secure and uninterrupted.

MOL told Platts that current Danube water levels do not affect operations at its 165,000 b/d Danube refinery near Budapest and that measures are in place to ensure continued water supply even if levels fall below historical minimums. The company acknowledged that low water limits barge logistics throughput but said it does not affect regional fuel supply and MOL's refinery is not drawing on strategic reserves.

Austria's Schwechat refinery is not currently impacted by Danube water levels because its refining system is not supplied via inland waterways, according to OMV. "While there are some restrictions related to product distribution, these can be effectively mitigated through alternative transport options and by adjusting supply patterns within our subsidiary network," OMV told Platts.

Danube not Rhine

More than 1 million mt of petroleum products were transported downstream through the Upper Danube Hungary-Slovakia cross-border point in 2025, while about 20,000 mt moved upstream, according to the Danube Commission annual report. Some 520,000 mt moved downstream through the Middle Danube Hungary-Serbia cross-border point, while 87,000 mt went upstream.

"The river transport of petroleum products is difficult, so we import 20%-25% of the planned quantities because the capacity of barges has been significantly reduced in order to be able to cross the river and safely deliver petroleum products," Đedović Handanović wrote on her Instagram account. The Serbian government has authorized oil companies to tap operating reserves to maintain market supply, according to the minister.

Europe's hot, dry summer has reduced water levels across the continent's inland waterways, with critical conditions threatening to halt traffic entirely on the Rhine River within days.

Platts' benchmark price for ultra-low sulfur diesel cargoes delivered into Northwest European ports was assessed at $1,265/mt, up from an average price of $987/mt in June. Diesel barge prices in the Amsterdam-Rotterdam-Antwerp hub were last assessed at $1,254.75/mt, down from an average price of $970/mt in June.

Amsterdam-Rotterdam gasoline barge price was assessed at $1,080.5/mt on July 28 by Platts, up from an average of $945/mt in June.

The Danube's low-water event may not be as severe as conditions on the Rhine because most refineries can still clear product via pipeline or railway, lifting the brunt of the impact, said Sammir Lesage, analyst at S&P Global Energy CERA.

The Danube Commission Secretariat said July 28 that shallow sections in Hungarian, Serbian, Bulgarian and Romanian stretches typically pose the main obstacles to navigation during low water periods. Latest reports indicate a narrowing of the navigation channel at several locations in Bulgarian-Romanian and Hungarian stretches, according to the commission, an international intergovernmental organization overseeing Danube navigation.