The Viennese adore the River Danube. Over the centuries, they’ve depended on it for drinking water, food, and the movement of people and goods. It flows, after all, through four more capital cities before it empties into the Black Sea. On New Year’s Eve and at weddings, Austrians dance to Strauss’ joyous love song for the river, The Blue Danube waltz. Even today, the river is such a part of city life that it seems the residents believe that it runs through their back garden.
Vienna has the Danube to thank for its prosperity but, for centuries, it also lived under threat of capricious, catastrophic floods. Picture Austria and you think of mountains but the skiing capitals of Salzburg and Innsbruck are hours away by train. Vienna, home to a quarter of Austria’s 8.8 million people, sits in a geographical bowl. It’s a risky place to put a city which was, until 100 years ago, the centre of an empire. Even in the 20th century, the fear that large parts of the city could be washed away was a constraint on Vienna’s growth.
In 1988, Vienna completed its largest ever civil engineering project to address the flooding problem. Over the previous 16 years, they had dug out a new channel for the river, built two massive weirs, and piled 30 million cubic meters of soil into an island between the old and the new river. Enough soil was excavated and repurposed to cover Vienna’s largest park, the Prater, to a depth of 5 metres. It would have buried New York’s Central Park under almost 10 metres of earth. This completed Donauinsel (Danube Island) is so big that you would only have to run once around its circumference to complete a full marathon.
The construction of the Donauinsel was a project so large, requiring so much cooperation from so many different departments, that even just 31 years after its completion, it seems almost inconceivable that it could have occurred.
This is the story of how the city protected itself for the future, but also that of how the city gave its people that island as a gift.
For much of its history, Vienna perched not on the straight, steady river of today but on wetlands. Unregulated rivers flood and, in 1501, this happened cataclysmically.
The 1501 flood is as yet unmatched but as we face climate crisis, increasingly extreme summer storms and meltwater from what would previously have been freak winter snowfalls, 1501 plays on the minds of city planners. That flood destroyed bridges throughout Vienna and swept farms, orchards and livestock away. It was so destructive that, in the aftermath, Vienna’s land boundaries were completely redrawn. Landowners had lost their lives or been forced to abandon their property. For thousands of people in the city, it was time to start again.
1501 was the largest flood in Vienna’s history, but it wasn’t the last. The city lived with regular floods until the 19th century, when the Hapsburgs were at the height of their power. Famously, the emperor Franz Joseph vowed to remake the centre of Vienna. In a 30-year redevelopment project, Franz Joseph tore down the old city walls and replaced them with the Ringstrasse; a wide boulevard inspired by the streets of Paris. They erected the new Rathaus (city hall), Parliament, theatres and museums in a variety of architectural styles to give the illusion that this city-wide remodelling had happened organically, over centuries, in the context of an empire which had endured for generations and would continue for generations to come.
At the same time, Vienna’s population exploded as people came from all corners of the empire to work. In the same year the Ringstrasse was to be completed, the population was projected to break 1 million for the first time. Many of the new arrivals settled in low-lying areas of the city such as Leopoldstadt (today’s second district) and the villages of Stadtlau, Floridsdorf and Jedlsee on the other side of the Danube.
Whether the new residents knew it or not, their homes and livelihoods were in danger. The first district was on a slope, meaning that Stephansdom cathedral, the Hofburg palace, and the brand new Ringstrasse were never at risk; it was the residential districts which had to be protected if the city was to continue to prosper. We can only imagine the frustration of the Emperor who had just made over his city to his personal tastes, a man who kept lions in the garden of his summer palace and had maintained hunting ground the size of a medium sized town within the city limits, when his river wouldn’t behave.
The arrival of the telegraph in the 1840s brought some relief. With the telegraph, warning could be sent downstream from Linz when flooding was imminent. A message relayed to Vienna gave the people a days’ notice. It wasn’t much but it was enough time to protect their belongings and move to high ground instead of scrambling to the roof as the water rose around them. Understandably, the citizens continued to complain that this was not enough.
The Hapsburgs took radical action to address the problem in the 1860s and 70s. Franz Joseph enlisted the engineer behind the newly completed Suez Canal and they brought the Danube under control.
The plan was this:
First, they would build the Donaukanal (Danube Canal). The new canal would separate Leopoldstadt from the first district and run from the northern to the southern edges of the city. Thanks to the weirs and locks at the borders, the water level would remain almost constant.
Then, on the eastern side of the districts of Leopoldstadt and Brigittenau, they would carve a whole new riverbed for the Danube proper.
Finally, the old curve of the river would be set aside as the Alte Donau (Old Danube) which still exists in the 21st and 22nd districts as a haven for nature and leisure.
Instead of uncontrollable wetlands, their plan gave Vienna efficient, dependable shipping channels and a wide area which could be flooded without damage to the city.
The defences were undeniably a great feat of engineering and life in the city improved. In relative safety, Vienna grew to absorb the previously precarious villages on its outskirts. The expansion of the city continued even as the Hapsburg dynasty came to an end, even as two world wars took Vienna from the central pearl of a sprawling empire to the ‘fat head’ of a country depleted of land, resources and population.
But Franz Joseph’s defences only held for 70 years.
In 1954, another flood ravaged the new districts. Thousands of people were evacuated from their homes. An outraged public demanded urgent plans for new flood protection.
Vienna reckoned with a number of solutions. Bigger dams were proposed but these would have been too dangerous were they to fail. The option of broadening the channel was discussed but making the river wider would also make it shallow, causing problems for large modern barges. Diverting the river to the north was a possibility but that area was already earmarked for development as the city recovered from the war.
Enter the Austrian engineer August Zottl, the first in his guild to occupy himself with the problem of alpine floodwaters. In 1957, when three years of calm weather had failed to dampen public interest in the project, he presented his plan to protect Vienna.
From the beginning, Zottl designed his system to cope with a flood of the same magnitude as that of 1501. His proposal was to build a second channel for the Danube parallel to the one dug in the 1870s. There would be a weir at the top of the new channel, which could be opened in the event of flooding to take pressure off the shipping channel. There would also be new motorways on the banks, which in times of absolute peril would act as an artificial flood plain in order to protect the city. And what to do with the vast amount of earth they would have to excavate? Place it between the two channels and construct an island from scratch.
Zottl’s plan was complicated, and he had to be persistent to win over the planners. It wasn’t until 15 years after his initial proposal that the city agreed to start work and, even then, the ground was broken before anyone had agreed on what to do with the new land they would create.
The Donauinsel is 21km long and 210 meters at its widest point. To the south, it extends all the way to the city’s border. To the north, it goes most of the way to the neighbouring town of Klosterneuburg. The idea of a modern city presented with such a vast new area for development was unheard of. Naturally, there were a lot of opinions on what to do with the land. Some wanted to use it for a major new train station, others a university campus, others for factories.
While building work continued, executives and planners sat in boardrooms, focussing largely on the idea of an industrial estate. On the Ringstrasse, however, crowds of people, the majority of them students, marched to demand that the new land be given to the people. It seemed like the most logical solution, they argued, since the people were using it already. In the summers of the 1970s and 80s, long before there was even a blade of grass on the island, sunbathers laid out their towels on the gravel and spent the day lying under the cranes.
In spite of complaints that their demand was ‘communist,’ the protesters won. Not only would the people have access to the whole island, it would be free and without fences. No private clubs. No golf courses. No industry. Just a vast space for recreation.
Today, three of Vienna’s five underground lines have stations either on the Donauinsel or the riverbank, so that the people can reach it directly from most of the city. On the island, you’ll find everything from the world’s biggest floating trampoline complex to a wakeboard lift, Saturday morning kite festivals to Vienna’s Muggle Quidditch team. There’s a grammar school built on a boat moored to the island and a number of beaches reserved just for dogs. There are pontoons from which people jump into the new river channel and swim to the other side. There’s a playpark with a stream running through it where kids build muddy sandcastles in the middle of their landlocked country. In the more secluded parts of the island, there are also nudist beaches.
Every year since 1984 (four years before it was officially completed), the island has played host to Donauinselfest, a music festival that calls itself the biggest free outdoor party in Europe. Big-name acts travel from around the world to play to almost 3 million visitors. Most years, the Vienna Symphony Orchestra also puts in an appearance.
Vienna continues to invest in the Dounauinsel too. Wi-Fi is now available on a large part of the island, allowing people to work in the fresh air. The island is home to 1.8 million trees and, now they are established, projects are being undertaken to maximise the space as a habitat for diverse wildlife. Community gardens are also increasingly popular. Just last year, the city gardeners planted an orchard of 30 fruit trees. Anyone is welcome to harvest the fruit, provided they take only as much as they can hold in their hands.
Most happily, Zottl’s flood defence plan was such a success that a great deal of Vienna’s population is unaware of the critical role the Donauinsel plays. On average, the weir is opened twice a year so the new channel can take the extra water. The biggest test of the system came in July 2013 when overwhelming storms hit the Danube basin. Vienna experienced more than two months’ worth of rainfall in two days. The Donauinsel was partially flooded but, while towns such as Passau were devastated by the worst floods since 1501, Vienna was undamaged.
The Danube hasn’t flowed through the centre of Vienna since the Donaukanal was first constructed. Bratislava castle is built on a rock overlooking the water. The famous Hungarian Parliament building sits on the water too, as does the whole of Old Belgrade. In Vienna, however, you have to walk for several kilometres to get from the first district to the river. You can’t see the cathedral from the water, or Karlskirche, or the Opera, or the Riesenrad Ferris wheel.
But while the Danube doesn’t run past Vienna’s most famous tourist attractions, it does go through the area where people actually live. The turbulent history of Vienna and its river was never a struggle to protect its crown jewels, its religious artefacts, its palaces. It was about saving people’s homes and their ability to put down roots without fear that they would be washed away.
Now that the flood risk is mitigated, the river is more important than ever to the Viennese as part of their life outside work, although it could be argued that an island wrought by all the might of 20th century engineering technology is a surreal place to to withdraw from the pace of urban life. Though visitors know that the island is still new, the trees have grown and the paths have weathered to the extent that the island no longer feels man made. Most importantly, if you take a bike and cycle for 20 minutes, you can only see the city in the distance. To be within the borders of a European capital and yet have it be so easy to escape is a gift.
In 1988, when the Donauinsel was opened, it was estimated that 100,000 people a day would visit. 30 years later, in a city of only 2 million people, you’ll find 2–300 000 of them somewhere on the island when the sun comes out. Beer in a cooler, someone cycling up and down the footpaths selling ice cream, sun cream (hopefully) applied, the Viennese still love nothing more than a day in the fresh air by the water. And, on days like that, it must be said that the river is, quite astonishingly, blue.