The recharge – discharge process of the Peschiera spring system (central Italy)

The springs of Peschiera are situated in the Velino river valley, a few kilometres upstream of Cittaducale in the province of Rieti. They form the largest group of springs in the central Apennines with their 17 m3/s environ average discharge, collected and diverted by ACEA to supply Rome and much of its hinterland. Our research presented herein had various purposes, including determination of the hydrogeological catchment area, the study of the hydrodynamics of the limestone aquifer and a complete hydrogeochemical study not only of the large springs in question but of all the many sources in the middle Velino valley. Various types of models were used: a numerical model quantified the aquifer’s recharge-discharge process and verified its area; using various mathematical models, based on spring discharge data, we determined the regulating reserves and the renewal times of the resource and various other parameters useful for its sound management. Finally, analysis of the chemical and hydrodynamic properties highlighted the differences between the Peschiera waters and those of the other springs either side of the valley. Our study represents an integrated innovative approach that may be successfully applied to other large springs in the Apennines and Alps. It lends insights, on a mathematical basis, into the recharge-discharge process of limestone aquifers, which is of use to define the source protection zones concerned.