Facts and figures - the Alte Donau

The Alte Donau, a former river branch of the Danube, is situated in the municipal districts of Floridsdorf (21st) and Donaustadt (22nd). Some 30,000 people live within a one-kilometre radius of the urban lake.

Jetty by the water, on the right are sailboats,  in the background a skyline

The urban lake covers a surface area of some 1.6 square kilometres, which is equivalent to over 200 football pitches. The Alte Donau (Old Danube) contains around 3.7 million cubic metres of water and has an average depth of 2.3 metres.

Due to a narrow section in the centre, the urban lake is naturally divided into two large basins - the Obere Alte Donau (Upper Old Danube) and the Untere Alte Donau (Lower Old Danube). To the north-west lies the "Water Park", which was separated from the main body of water through the building of an artificial gravel embankment.

On average, up to 1.2 million bathers visit the Old Danube every year. The urban lake is thus one of the major local recreation areas for the Viennese population.

Sports and recreation on the Alte Donau

Ecologically valuable habitat

Beaver on the shore

It is not only its status as a highly popular recreation area that makes the Alte Donau one of the highlights of Vienna: the urban lake also plays a highly important role as an ecological niche. The restoration measures undertaken over the programming period of the project LIFE+ Alte Donau have proven highly successful: extensive reed zones, planting of characteristic lakeshore vegetation and a sophisticated approach to lake management have helped to attract a multitude of plant and animal species.

More than 20 fish species populate the waters of the Alte Donau. Besides well-known types such as zander, pike and wels catfish, the urban lake is also home to lesser-known fish including rudd, bleak and bream. Large numbers of animals also live in the area above the waterline, including some protected species: various types of amphibians, waterfowl and songbirds, dragonflies and the strictly protected beaver.

Endangered plant species have also been successfully reintroduced, with yellow flag iris, water lilies and flowering rushes a prominent sight around the lakeshore. With some 45 different species, the biodiversity of the lakeshore reed beds is gratifyingly high.

Commercial use of the lakeshore

Not only is the Alte Donau a high-quality recreation area and an ecologically valuable waterside habitat in the middle of Vienna, a city with over a million inhabitants; it is also home to a substantial number of leisure businesses.

Commercial use of the Alte Donau lakeshore has intensified substantially in recent years. At present there are eleven boat-related businesses, i.e. boat-hire companies and sailing schools, plus rowing, sailing and other water sports clubs. In total, some 1,500 boats are registered on the Alte Donau. Besides these there are numerous restaurants, cafés and bars, many of which are attached to boat-hire facilities. The majority of the businesses on the Alte Donau are members of the marketing association Die Schöne Alte Donau (German), which provides information for visitors.

Ownership of the Alte Donau

The Old Danube is owned by Donauhochwasserschutz-Konkurrenz (DHK) (the Danube Flood Protection Association), except for some small areas around Gänsehäufel island and the Dampfschiffhaufen peninsula which are under the sole ownership of the City of Vienna. DHK is co-owned by the Federal Provinces of Vienna and Lower Austria and the Republic of Austria, with via donau - Österreichische Wasserstraßen-Gesellschaft mbH (the government agency for the preservation and development of the Danube waterway) managing the properties on its behalf. Maintenance works are carried out by Municipal Department 45 - Water Management and via donau on behalf of DHK.

Logo of the LIFE+ Programme of the European Union: The word "Life" in yellow, surrounded by yellow stars

The LIFE+ Alte Donau project was funded under the LIFE+ Programme of the European Union as part of the "Environment Policy and Governance" strand.

Further information

Contact for this page:
City of Vienna | Water Management
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