Stefano Maran*, Davide Bavera**, Stefano Barontini**, Roberto Ranzi Libro: Water resources assessment and management under water scarcity scenarios Centro studi idraulica urbana * CESI RICERCA ** UNIVERSITA’ DI BRESCIA The knowledge of the water availability in a river catchment is a fundamental information for all the human activities taking place there and for the ecosystem prevention, in order to apply sustainability criteria to the design of hydraulic structures and to the water management scenarios. In mountain basins, a relevant amount of water available for human activities is given by the runoff in rivers and creeks. Unfortunately a direct measurement of flows, in mountain and particularly in alpine basins, is often not possible. The flow regime there is highly variable and the stream channel morphology makes measurements very difficult. It is therefore of key interest to provide some reliable regionalisation methodologies in order to obtain an accurate estimate of the Flow Duration Curves (FDCs) for ungauged river sections. It is also important to apply these methodologies to wide investigated areas, as well, in order to provide regional relationships able to extend our knowledge to a large number of basins of interest. In this study we will present and discuss the methodologies we applied to obtain regional relationships proposed for wide areas in the Northern Italy. Such methodologies provide regional relationships for the high-duration range of the FDCs at ungauged sections, starting from common and easily retrievable geomorphoclimatic data. Our work conceives some basins in the Northern part of the Alps, from the Piave River basin up to the Grana River, near the Po sources, and a wide range of area and elevation classes is covered by our analysis. The target area should be distinguished into two main areas: from the Piave to the Adige River basins and the Po River basin. For both these areas some regionalisation relationships were provided for the average flow and for flows characterised by three official duration in the Italian practice (182, 274 and 355 days). A local area regionalisation analysis was performed over some basins around the Monte Rosa massif, also in order to verify the large scale regionalisation analysis. As an example of application, the study also compares the water availability with an estimated touristic demand in winter and some techincal parameters for the desing of artificial snow plants are suggested.