WP 5 Analysis of present IWRM practices - Brahmatwinn

Discharge in m3/s
2500
2000
1500
1000
500
0
Danube, Achleiten, 1900-2004
Fig. 1: Hydrograph of Danube River at gauge Achleiten
The figure shows the hydrograph of the Danube River at gauge Achleiten. Average discharge in this
long time period is about 1400 m 3 /s. In comparison to the hydrographs of the rivers Salzach and Lech
it can be seen that the runoff variability is not so high. Major runoff occurs in the summer month,
when precipitation is highest.
2.1 Policies and measures to cope with hazards
The Danube region has to cope with floods as a major problem. These floods occur mostly in summer
time when snow- and glacier melt coincides with extreme precipitation events. In other areas, e.g. in
the north of Bavaria exist times with too less water availability. Strategies how these problems were
managed in an institutional and structural way, were presented below.
2.1.1 River linking for improving water availability
One important measure to avoid floods and droughts and to establish a good water balance is the
Main-Danube-Channel in the upper course of the Danube. The Danube River is linked with the Rhine
River Basin by way of a channel, which was completed in the year 1992. With the water transfer from
the Danube to the Main the following principal objectives are achieved:
• Improvement in the quality of the water at times of low discharge,
• Compensation for evaporation losses caused by the operation of the thermal power stations,
• Reduction in the number of floods in the valley of the middle Altmühl in summer
(BAYERISCHES STAATSMINISTERIUM FÜR UMWELT, GESUNDHEIT UND VERBRAUCHERSCHUTZ 2005).
Some water of the Danube River is diverted to the Main River, because of the low water level of the
Main and the advancement of the flood control in the Altmühl valley downstream of Gunzenhausen.
It shall be reached an improvement of the low water availability in northern Bavaria in the Main
basin. In Bavaria, the water resources are subject to highly varied conditions. Whereas Southern
Bavaria is rich in water due to its high precipitation, water is short in supply in large parts of Northern
Bavaria. At times of low discharge, there is three times more water available per inhabitant in the
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