The confluence of the Brigach and Breg Rivers around Donaueschingen located in the Black Forest, Baden-Württemberg, is the source of the Danube. Over 56,184km² in Bavaria and Baden-Wuerttemberg are drained by the Danube – almost 17% of the entire country and 7% of the Danube River Basin. Some 9.4 million inhabitants live in the area, which makes it about 11.6% of the population of the entire basin.
Landscape, Climate and Water Flow
From its source, the Danube flows 584 km to the Austrian border. Interestingly, the Danube loses about half its discharge to the Rhine Basin through underground passages in its upper course near Immendingen. The largest tributaries to the Danube in Germany are the Naab, Isar, Lech, Inn and Salzach Rivers. The German Danube region includes the Swabian and Frankonian Jura, parts of the Upper Palatinate and the Bavarian and Bohemian Forests in the north. To the south lie the Swabian-Bavarian-Austrian foothills. The Alpine Rhine and Lake Constance as well as the southern tributaries of the Lech, Inn and Salzach Rivers make up the southern borderline.
The Atlantic Climate influences the German Danube region with an average precipitation of about 1,030 mm per year, increasing from north to south. The average monthly temperature is at its minimum in January (Danube Valley –1°C, Bavarian Forest –2°C, Alps –10°C) and reaches its maximum temperature in July (Danube Valley 20°C, Bavarian Forest 18°C, Alps 4-10°C).
Of the 9.2 million inhabitants living in the German Danube Basin, 41 % live in urban areas with more than 100,000 inhabitants. The most important settlements and industry centres are located around these cities, such as the automobile and machine industries. In addition, 57.5 % of the German Danube region is used for agricultural activities.
Hydropower currently amounts to a 15 % share of the total energy consumption in Bavaria. About 13 billion kilowatt hours are generated annually in 4,250 water power stations – 90% of this is generated in 218 large plants of over a 1,000 kilowatt capacity. From Kelheim on, the Danube serves as an international waterway. The river is also linked with the Rhine River Basin by way of the Main-Danube Canal, connecting the Main River at Bamberg with the Danube at Kelheim in Bavaria.
Rivers have been used as receiving waters for both urban and industrial wastewater effluents for hundreds of years. They also transport diffuse pollution loads. Over the past decades, general water quality has improved considerably through large investments into wastewater treatment plants. There have been substantial reductions in the oxygen-sapping organic substances and nutrients, such as phosphate and nitrogen. Since 1950, the number of wastewater treatment plants has increased from 20 to about 3,000. In the year 2000, around 93% of the Bavarian population was connected to these wastewater disposal facilities. The wastewater of the remaining 7% is treated in around 190,000 small wastewater plants.
Since 1975, water body protection includes measures specifically relating to the treatment of mixed water and rainwater. So far, storm-water tanks with a total capacity of 1.95 million m³ have been built.
For detailed information on the above, please download the 'Facts & Figures' fact sheet below.