Hydropower is the main energy source in Switzerland and its development during last century followed increasing electricity consumption from households, industries, and rail transportations. Nowadays, the development of new important infrastructures is more difficult than before, but the branch nevertheless have to face new challenges. On the economic side at first, with on one hand a still growing demand added to the political will to completely turn off nuclear power by 2050, and on the other hand, difficult market conditions, with very low selling prices, limiting investments. On the climatic side then, with a global scale warming with uncertain consequences on water disponibility (either from direct precipitations or through snow- and glacier-melting). The present study lies within the frame of Swiss Confederation research program SCCER-SoE and will explore future constraints, both economical and climatic, and try to propose solutions or reflexion leads to adapt hydropower operations. It will be based on the numerical simulation tool Routing System 3 and the study case of Kraftwerke Oberhasli, in the Upper Aar River bassin in Switzerland.