A Norwegian dam partly collapsed on Wednesday, sending water gushing through a gaping hole in the structure, after days of heavy rain triggered landslides and flooding in the south of the country.
Hatches at the Braskereidfoss hydroelectric dam on the Glomma River, Norway's biggest waterway, had failed to open after its control room flooded.
Earlier it was reported that authorities were planning to blow up part of the dam to prevent it from bursting and putting downstream communities at risk, but the idea was scrapped after water broke through the structure.
Water appeared to flow through the dam in an orderly manner following the breach, according to utility group Hafslund, and police said there were no immediate signs of major downstream flooding.
“The water has gradually begun to seep through the side of the dam, and, as of now, it is not appropriate to take any measures at the power plant,” police spokesman Fredrik Thomson told reporters.
He added that the situation is being assessed continuously.
At least 1,000 people live in communities close to the river in the area, and authorities said that all had been evacuated before the dam began to fail.
A Norwegian woman in her seventies died early on Wednesday after falling into a stream the day before. She crawled on to the bank but the floods prevented emergency services from reaching her for several hours.
It comes after Storm Hans battered parts of Scandinavia and the Baltics, damaging roads and injuring people with falling branches.
Extreme weather across Europe this summer has led to floods, storms, wildfires and heatwaves causing havoc across the continent
In Slovenia, European Commission President Ursula von der Leyen said floods that killed six people were “a national and European tragedy”.
The waters washed away bridges and electricity lines and forced thousands of families to evacuate homes, she said as she offered €400 million ($439 million) from an EU solidarity fund.
“Your idyllic landscapes turned into a hell of water and mud. Not even this Alpine paradise has been spared by the impacts of climate change,” she told Slovenia's parliament.
Flash floods were also reported in neighbouring Austria and Croatia and heavy rains and storms caused major damage further east in Serbia.
In Greece, 47 fires were brought under control in the past 24 hours, but eight regions are on high alert as strong winds increase risks.
More heavy rain was expected over Norway and Sweden as sheds, small houses and mobile homes floated in rivers or were carried away by strong currents.
In Gothenburg, Sweden’s second-largest city, large parts of the harbour were under water. A Swedish train derailed on Monday when a railway embankment was washed away by floods, injuring three people.
Norwegian meteorologists predicted up to 30ml of rain by Wednesday evening. They said “the quantities are not extreme, but given the conditions in the area, the consequences may be”.
Their Swedish counterparts issued a red warning for the West coast, saying “very large amounts of rain causing extremely high flows in streams” could be expected.
“We are in a crisis situation of national dimensions,” Innlandet county mayor AUD Hove said.
“People are isolated in several local communities, and the emergency services risk not being able to reach people who need help.”