High-head storage hydropower schemes in Alpine areas are required to produce peak energy and to regulate electricity grids. Nevertheless the unsteady turbine operations induce hydropeaking in the river downstream of the powerhouse. The developed hydrological-hydraulic model can simulate glacier melt, snow pack constitution and melt, soil infiltration and run-off as well as hydraulic structures and hydropower schemes. The operation of complex plants and the resulting ecological impact are generated. The modelling process is explained for the upper Aare River catchment in Switzerland, containing the Oberhasli hydropower scheme. For a simplified catchment area, systematic simulations define the influence of meteorologic, hydrologic and morphological parameters on the river flow regime for natural as well as operated catchments. In a second step, the model’s ability in reproducing hydropeaking at the outlet of the upper Aare River catchment is tested. Finally operation rules induced by the dynamic electricity market are simulated.