Climate activists protest on the Danube's dry banks

STORY: Campaigners dragged kayaks to a large stretch of shoreline exposed by low waters near the southern border town of Zimnicea - and held up banners saying "We want Danube waves, not heat waves."

Record high temperatures, drought and deforestation have left rivers in Romania at half their usual level for August, data from the water management agency shows.

"According to weather forecasts, the drought will be prolonged, putting pressure on the country's energy system, food security and water access," Vlad Catuna, a campaign coordinator for Greenpeace Romania, said in a statement about the protest.

Authorities are rationing water supplies for nearly 700 villages and farmers who rely on the Danube for irrigation have also taken a hit.

Romanian state hydro power producer Hidroelectrica said in late July its electricity output dropped by a third in the first half of the year. Port operators say barges carrying Ukrainian grains to Romanian ports cannot manage full loads because of the low river levels.