Groundwater in the Urban Environment: Management Needs and Planning Strategies

Problem statement: Over the past thirty years urban transformations, such as urbanization, suburbanization, dis-urbanization and re-urbanization processes, have modified the subsurface conditions of Torino (NW Italy). In order to contribute to the solution of the problems concerning groundwater the conceptual model for the groundwater flow system, the schematization of the aquifers boundaries and the estimation of basic hydrogeological parameters are among the main issues which should be investigated. This study was mainly aimed at illustrating (i) a new interpretation for the Torino urban area hydrogeological setting (ii) highlighting the current groundwater criticisms and (iii) emphasizing the priority actions to implement a good urban groundwater management system. Approach: Starting from the analysis of the existing subsurface data, a comprehensive description of the general geological setting had been performed, three main (hydro) stratigraphical Units had been described and their reciprocal relationships had been detected. On the basis of the available data, the unconfined groundwater natural seepage had been reconstructed, a hydrogeological map and a cross section illustrating the units characteristics had been produced. Results: The analysis highlighted three main groundwater criticisms: A natural unconfined groundwater level uplifting in the quaternary unit 1, a widespread inorganic pollution under abandoned industrial areas and many interference problems with the groundwater in unit 1 caused by the new transport infrastructures. Another important problem was the scarce geographical density of the existing groundwater monitoring network operating in the urban area. Conclusion: Solutions to specific, local problems can give the opportunity to transform some of the above mentioned problems into useful resources for the territorial development. The expansion of the groundwater observation network clearly appeared to be the main action to be implemented by the public authorities. Other successive actions could be the construction of a multipurpose interactive real-time mathematical model of groundwater movement in the urban area and the development of improved methods for predicting changes of hydrogeological conditions.