Author(s): Jurgen Giesecke; Matthias Schneider; Klaus Jorde
Keywords: Hydropower; Minimum flow; Diversion; Simulation model; River ecology; Fish habitat; Hydromorphology; CASIMIR
Abstract: At hydroelectric power plants of the diversion type the three main habitats of flowing waters, the river bottom, the aquatic zone and the riparian zone and flood plains are particularly severely affected by reduced discharge. This is manifested in the changes of the available habitat for species typical to these natural areas. The simulation model CASIMIR enables the ecological and economic effects of instream flow regulations in diverted river sections to be calculated and compared by means of habitat forecasts with simultaneous determination of electricity generation. First of all the requirements of macrozoobenthos can be considered and habitat forecasts obtained by calculation of the pattern of flow forces near the river bottom. In addition the module SORAS makes it possible by means of hydraulic and structural simulations to determine the effect of certain discharges on the habitat size and quality for fish and macrophytes. In the present case of the study of hydroelectric power plants and the stretches of water affected by them, the modular structure of CASIMIR permits the extent of the study to be modified to suit the financially justifiable framework of the individual project.