The MINERVE project was initiated for flood management in the Upper Rhone river basin. Its first goal is the prediction of floods. The second one is the optimum management of the complex system of hydropower plants located in the basin in order to diminish the peak discharge in the Rhone River and its tributaries. The MINERVE Interactive Decision Support (MINDS) proposes turbine and bottom outlet preventive operations before the flood peak, for having storage volume in the reservoirs during the peak flow. The iterative ranking Greedy algorithm allows successive resolutions for all the hydropower plants in an iterative way until reaching the optimum operations of the whole complex. The multi-criteria analysis optimises the start and the end of the preventive operations (turbine and bottom outlet operations) for the whole ensemble hydrological forecasts for a selected hydropower plant.