Located between the Val d’Hérens and the Val d’Anniviers, the Vallon the Réchy is a study basin aiming to monitor water resources in high mountains valleys (STRADA project). The basin’s surface is 17 km2 and the mean elevation around 2’450 masl. Four different sub-basins as well as the river Rèche have been defined from the geomorphology characteristics of the basin and have been modelled in RS MINERVE. The goal is the calibration of the hydrological model with observed discharges in order to simulate the snow variation and the hydrogeological response of the basin. By: CREALP (Switzerland).