Despoina Charchousi

and 2 more

Over-pumping and extended drought events have raised awareness on groundwater resources management within the Mediterranean Basin. As groundwater often has an important role in sustaining certain types of aquatic, terrestrial and coastal ecosystems, water policy makers should pay special concern to maintain groundwater contribution to the environmental flow. To this aim, the present study focuses on the assessment of a newly introduced groundwater management tool, the Groundwater Footprint (GWF) (Gleeson et al., 2012). GWF represents a water balance between aquifer inflows and outflows, focusing on environmental flow requirements and expresses the area required to sustain groundwater use and groundwater dependent ecosystem services. GWF is applied to a pilot aquifer in the Mediterranean Basin, crossed by an intermittent river. Total abstraction, natural and artificial recharge, groundwater contribution to environmental stream flow are the critical parameters related to GWF estimation. In order to estimate groundwater contribution to the environmental stream flow, the assumption that groundwater contributes to the environmental flow to the same percentage as baseflow contributes to the natural flow has been made. However, the main constraint met in GWF estimation has been the estimation of the environmental flow in non-perennial river, as the quantification of the environmental flow requirements has been mainly studied for perennial rivers. For this reason, the available to the literature studies referring to environmental flow requirements have been assessed and the most appropriate method for the specific pilot area has been applied. The ratio GWF to the actual area of the aquifer (A) can be used to assess groundwater management, as GWF/A>1 indicates unsustainable groundwater consumption. Consequently, GWF/A may consist a comprehensible to the general public groundwater stress indicator and can be used to raise awareness.