Evaluating the Available Regional Groundwater Resources using the Distributed Hydrogeological Budget

In this study, several hydrogeological catchments of Central Italy have been characterized focusing the attention on the presence of areas in which, over the last two decades,the hydrological equilibrium between recharge and discharge (phenomena of marked reduction of spring discharge and progressive drawdown of groundwater levels) has been compromised by overexploitation of groundwater resources. A GIS system has been used in order to develop the study and the homogenous distribution of the hydrological knowledge and of the existing imbalances has been performed. Characterizing elements of the research are: a) the definition of the hydrogeological units; b) the hydrogeological survey of around a thousand water-points; c) the monthly analysis of climatic data of numerous survey stations; d) the census and the recording of water concessions; e) the evaluation of agriculture hydro-exigency derived from the analysis of the use of soil; f) the withdrawals defined by a statistic analysis of data. These elements have allowed to define the Distributed Hydrogeological Budget which is a useful instrument to evaluate critical areas.