<p>The Urban Geo Footprint (UGF) is a project currently developed in the framework of the EuroGeoSurvey Urban Geology Expert Group (UGEG) and specifically focused on the geo-environmental pressures in urban areas.</p><p>The main goal of the study is to set up a classification tool (UGF) aimed to identify the main geological features that could influence and/or interfer with (ongoing) anthropic activities within urban catchments.</p><p>The following main drivers are defined in the «UGF framework»: Geology, Climate, Geohazards, Geomorphology, Subsoil anthropic pressure. Each driving factor is articulated in quantitative and indexed (using scores) parameters. At the present early stage all these parameters are going to be indexed and weighted based on two levels of investigation: “basic” and “advanced”. The final result for each city is the “UGF INDEX”  coming from the combination of all the drivers specific scores. The higher the index value, the higher the geotechnical and environmental complexity of the urbanized catchment.</p><p>The expected outcomes of the UGF urban areas indexing are:</p><ul><li>A classification of cities according to their geological setting and climatic features, eventually allowing their clustering and supporting sharing of knowledge and capabilities among urban areas.</li> <li>Better understanding of geo-environment processes possibly interacting with urban subsurface and ground infrastructures, thus also encouraging and support cities’ subsurface resilience for sustainable (future) growth.</li> <li>Help for better assessing the ‘economic’ and ‘social well-being’ benefits (i.e. in terms of ‘geological resilience’) that could derive from urban planning associated to subsoil knowledge.</li> <li>A fact-sheet referred to the subsoil of each city, to be progressively updated.</li> </ul><p>Other objectives of the project are:</p><ul><li>Contributing to develop a method for the comparison of data from different environmental urban contexts.</li> <li>Improving the European collaboration and, therefore, the exchange of ideas on good practices to increase urban areas’ resilience.</li> <li>Improving citizens' awareness of both the resources and the threats associated with geology.</li> <li>Produce a tool for decision makers support (e.g. urban planning, hazards prevention) in order to obtain economical and social well-being benefits.</li> </ul>

This paper proposes a preliminary and large-scale survey methodology to identify areas suitable for indepth analysis for the application of Sustainable Drainage Systems and Managed Aquifer Recharge. These techniques are frequently applied to increase the natural infiltration capacity of water into the ground and their effectiveness depends on the local hydrogeological and morphological characteristics. The study area is the city of Rome where the aim is to mitigate the problems related to rainwater which, in case of extreme events, struggles to infiltrate into the ground, overloads the undersized drainage systems, and floods the urban space.The proposed method involves GIS geospatial analysis of the permeability of outcropping lithologies, the digital elevation model, and the piezometric levels of the aquifers. To identify the suitable zones, areas characterised by high permeability and a piezometric level that would confer a volumetric capacity to possibly store even large quantities of water, without triggering possible problems of water table rise, were identified. Data were divided into classes and indexed to compare and overlap them. Furthermore, the final result was compared with the urban flooding phenomena and the soil permeability map of Rome. The results of the performed analysis show that the preliminary suitable conditions to apply SuDS and MAR in Rome are widespread. The geological setting of the city is characterised by permeable lithologies in many places with an effective infiltration potential that would allow rainwater to infiltrate the subsoil and reach the first available aquifer.

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This study reports the impact of hydrological conditions on salinisation and nitrate concentrations of a coastal aquifer located at the Mediterranean Sea, southern Spain. Eighty-two samples of ground-and surface water taken during two extreme hydrological events between 1994 and 1996 at 25 different wells were evaluated with regard to hydrochemistry, focusing on nitrate concentrations and salinisation, which constitute the main hazard of this aquifer. Furthermore, hydrochemical data were analysed by principal component analysis (PCA). Additionally, in 2007 13 ground-and surface water samples taken at 12 different locations were analysed for stable isotopes of D/ 18 O, and one sample was analysed for 15 N. Since 1993 until present saltwater intrusion was observed only during dry hydrological conditions in 1994; it showed an irregular salinisation pattern probably related to locally elevated hydraulic conductivities. Nitrate concentrations increase significantly during wet hydrologic conditions owing to uptake of nitrate by rising groundwater. Stable isotopes of groundwater reveal an Atlantic origin of the precipitation that recharges the aquifer and a minor amount of groundwater recharge by the water coming from the La Viñuela reservoir, which is used for irrigation over the aquifer. 15 N isotopes point to a considerable input of nitrates derived from organic fertilisers.