Criteria for design, operation and maintenance of barrages and retention reservoirs for providing ecological transmissivity

Structures in rivers such as dams of flood retention reservoirs influence the river ecology. They affect the passage for many organisms, aquatic ones as well as terrestrial ones. In case of flood retention in reservoirs the discharge and the bed load transport regime is changed. Therefore the living conditions for the organisms change also. The negative impact on the river can be minimized by hydraulic conditions that provide ecological transmissivity for the organisms. And so a sustainable ecosystem can be established. At present there are a few types of structures existing which provide ecological transmissivity. But those can only be traced back to visual surveillance.Target of the project is to provide a catalogue of measures that can be taken to improve the ecological transmissivity of dams for flood retention reservoirs (new structures as well as restructured older dams). The theoretical basis for the evaluation of the dams results from a catalog! ue of living conditions for the organisms which will be developped in this project. That catalogue includes the required living conditions of the aquatic and the terrestrial organisms which for the river bed as well as the banks serve a natural habitat and migration pathway. The catalogue will be a useful instrument for evaluation of the ecological transmissivity of strucures in rivers.

Bernhard Westrich
Werner Konold

Rüdiger Siebel
Sandra Röck
Oliver Kaiser

VA

From: 2004.08.01

To: 2006.07.31

BWPLUS

Institute for Landscape Management, University of Freiburg