Danube alarm

At Kritzendorf, a Danube riverside town a few kilometers upstream from Vienna, the local volunteer fire brigade is camped on a bridge over a fast flowing stream. They're loading sand bags into boats and transporting them to weak points in the flood defenses.

"Our barriers are not high enough at the moment so we still have to build them up," said fire brigade Chief Peter Dussman. "Some walls have already been broken, and, well ... we've been working here for the last five days."

This scene is being repeated along hundreds of kilometers of the Danube River, from where it leaves Germany and enters Austria at Passau, to where it departs Austria another 60 kilometres (37 miles) along at the Slovak border. And of course, beyond that border - in Slovakia and Hungary - emergency workers like Peter are fighting not just the water, but their own fatigue.

"Yes, we've had no sleep for the last 40 hours - or almost no sleep. We have to build up the barriers during the night," he said, as messages kept coming in on the two-way radio hanging from his belt.

Unprecedented frequency

Danube river floods are common occurrences but the locals have only seen the waters this high once before - in 2002, in what the media then dubbed "the flood of the century." They expected it to be a once-in-a-hundred-year event. Now, just 11 years later, the second "flood of the century" is lapping at the feet of local residents.

"I have a house near the Danube and we know the flood comes sometimes. We had a lot of damage but, yeah, we just live with it,” said Günther Braun, whose house is standing in a meter (about a yard) of water just a short distance from where he is watching the waters rise. He jokes that his house stands on two-meter stilts.

After the 2002 flood, Austria invested heavily in improving its flood protection measures. Insurance companies are hoping that this will pay off with less damage to property - however, few people expected another flood of that magnitude so soon. In fact, for some communities - including the one Peter Dussman is trying to protect - the water is already nearing that "flood of the century" level.

"We currently have a level of 7.7 meters (25 feet) and the peak will be at about 8 meters and some centimeters and with this level … about 5 centimeters (2 inches) more than the century flood in 2002," he said.

Wednesday decisive

According to the Austrian ministry responsible for agriculture and environment, which manages the waterways, there are 18,900 volunteer fire-men and -women working in the flood-affected zone, along with 1,000 soldiers from the Austrian army. In just one 12-hour period during daylight hours on Tuesday, they brought 238 people to safety.

"Great job, wonderful, applause ... to all of them, yes," said Andrea Seiler, a local resident at Kritzendorf who had come to watch the rising waters, when asked what she thought of the reflective-vest-clad volunteers around her. Andrea lives high and dry in an apartment overlooking the Danube, but had never seen anything like this.

"A couple of years ago there was high water, but not that much," she said. "It's a nightmare - I mean, the people, the animals. Yesterday I heard so many deer are dying because they can't escape."

Wednesday will be a decisive day for the 200-kilometer (124-mile) stretch of Danube upstream and downstream of Vienna. On Tuesday evening some river measuring stations were already reporting levels approaching those of 2002, and experts were predicting these would be topped. In the town of Melk the local fire-station, the centre of flood fighting and relief efforts, was itself flooded.

On the riverbank at Kritzendorf, Peter Dussman is worried about the night ahead: "There are almost no volunteer helpers during the night, so we are on our own - and as we've been working for five days here now, it's pretty hard and we … we're facing a very challenging time."