Anwendung der Habitatmodellierung zur integrativen Bewertung von Schwall und Restwasser im Bereich der Wasserkraftnutzung

The current and future use of water power as a cost-effective and renewable energy source are increasingly leading to conflicts of interest between the declared environmental protection goals of the EU Water Framework Directive and the water energy sector. As such, it has become necessary to objectively assess and quantify the potential impacts of using water power on those biological quality criteria that are relevant for the Water Framework Directive, and to do so on a case-by-case basis. With the help of selected case studies, this paper offers insights into the applicability of habitat modeling as an integrative planning and assessment tool with regard to addressing peak and residual flow problems. The results of habitat modeling-based peak flow assessment conducted on the Alpenrhein and on the Enns indicate that the potential negative consequences for aquatic fauna cannot accurately be predicted without taking into account the river-type-dependent and river-reach-dependent morphological differences. They also clearly show the importance of season-based assessments of the peak flow problems, as, given the seasonal differences in discharge and water levels, basing an assessment on only one season would not be representative. Further, a study conducted on the Ybbs demonstrates how habitat modeling can be used to determine an ecologically sound residual flow level for typical local fish fauna.     

Praxiserfahrungen beim Einsatz der Ultrafiltration zur Aufbereitung von Wässern aus Karst- und Kluftgrundwasserleitern

KURZFASSUNG ?hnlich wie in Teilen ?sterreichs müssen auch in einigen Gebieten Bayerns oberfl?chennahe Grundw?sser bzw. Quellw?sser aus Karstgebieten für die Trinkwasserversorgung genutzt werden. Aufgrund der mangelnden überdeckung mit filtrierenden Bodenschichten kommt es nach Regenereignissen und bei Schneeschmelze oft zur Eintrübung der Rohw?sser, die meist auch mit einer mikrobiologischen Belastung verbunden ist. Der vorliegende Artikel beschreibt, wie das Verfahren der Ultrafiltration sich in den letzten 10 Jahren in Bayern bei der Aufbereitung solcher W?sser bew?hrt hat. Neben den wichtigsten technischen Grundlagen werden auch die realisierten Aufbereitungskonzepte vorgestellt.

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Experiences in the application of ultrafiltration for the drinking treatment of waters from Karst and cleft aquifers

SUMMARY In several regions of Bavaria, as in parts of Austria, it is necessary to use near-surface ground or spring water for drinking water supply. Due to an insufficient cover of filtering ground layers, such raw water tends to become turbid after rainfall events or snowmelt, often involving some microbiological contamination. This article describes the satisfactory experience that has been made with ultrafiltration treatment of such water over the past 10 years in Bavaria. The author presents the main technical fundamentals and reports on implemented treatment concepts.