Assessing water availability in the High Plain of Friuli Venezia Giulia, Italy, by integrating hydrological and hydrogeological modelling

In 2022 an exceptional drought hit northern Italy, including the Friuli Venezia Giulia region, located in the north-eastern part. According to the Regional Environmental Protection Agency (ARPA-FVG, 2024), the region experienced unprecedented changes in climate variables, especially in terms of maximum temperature values in spring and summer and annual cumulative precipitation. Precipitation anomalies overcome the 40% threshold in specific areas of the region (ARPA-FVG, 2024), with significant variations in the precipitation extremes detected by Arnone et al. (2024). Drastic decreases in water availability were observed by the regional water utilities, who had to cope with an unprecedented limitation of supplies, that peaked 50% in 2022 (ARPA-FVG, 2024). The present study arises from the request of one of the local water reclamation and irrigation authorities, the Consorzio di Bonifica della Pianura Friulana, to identify irrigation solutions to efficiently respond to the new needs and establish new management procedures of water supply. The local stakeholders comprise 8 municipalities and 5 irrigation districts. The aim of the study is to integrate well sampling data, diversion flow rate with hydrological and hydrogeological modeling to quantify surface and subsurface water availability in the study area. The changes in the hydroclimatic conditions are assessed through statistical analyses of the meteorological variable and the model outputs.