Droughts and Changes in Water Resource Availability in the Cuneo Province

Hydrological research conducted in the province of Cuneo, located in southern Piedmont, Italy, highlights significant trends in meteorological droughts, showing increasing duration and intensity over recent decades. Prolonged dry periods caused by low precipitation, often combined with high temperatures and elevated evapotranspiration, lead to severe impacts on agriculture, surface water resources, and socio-economic systems. This study identifies major drought events affecting the Cuneo area using standardized meteorological and hydrological indices: the Standardized Precipitation Index (SPI), the Standardized Precipitation Evapotranspiration Index (SPEI) and the Standardized Streamflow Index (SSI). The propagation of drought from meteorological to hydrological conditions is analysed by correlating basin-wide precipitation indices at various temporal scales with streamflow indices at the basin outlet. Spearman’s correlation coefficient, adjusted for autocorrelation, is used to determine the temporal scale with the highest correlation, providing an indication on the basin’s drought response time. Spatial variability in response times is further explored in relation to basin characteristics such as gauge elevation and drainage area. Beyond characterizing drought propagation, the study integrates the quantitative analysis with qualitative insights obtained collaborating with water utility managers. Their direct experience of droughts periods in the water supply system represents an invaluable source of information. We aim at combining the quantitative and qualitative pieces of information to link drought causes to their real consequences and impacts on the study area, addressing both physical and socio-economic dimensions.