And reduce the use of tankers in the face of tourist peaks
A team of ENEA experts has developed a multidisciplinary methodology that makes it possible to estimate the quality and quantity of potential water reserves in the aquifers of small islands. The aim is to increase the availability of water, especially in periods of drought and strong tourist influx, and, at the same time, to reduce the use of tankers. In particular, the case of the island of Favignana was studied, in the Egadi archipelago, in Sicily, where in summer there are up to 60 thousand daily tourist presences compared to 3.500 permanent residents. The ENEA researchers have estimated that the potentially available water reserves could meet the needs of around 20 people, calculating a daily consumption per capita of over 200 liters. Through hydrogeological measurements, chemical analyzes of groundwater and the calculation of precipitation and evaporation rates, the possible reserves were estimated and those of the best quality were identified or, on the contrary, those most exposed to the risk of salinization due to intrusion of water sea. "It is essentially a hydrogeological balance that, like the economic balance sheets, allows to estimate the infiltrations, but also the consumption and losses of water, in a context, that of Favignana, chosen for its climatic, geomorphological and the large number of tourists in the summer ”, explains Sergio Cappucci, one of the ENEA researchers who oversaw the study. “From this point of view, the ability to determine the amount of water that infiltrates the subsoil feeding the groundwater represents an important added value. The methodology used can be replicated in other contexts with significant benefits from a social, economic and environmental point of view ”, continues Cappucci.
“The communities of the islands have always used natural resources in a sustainable way and specifically, the use of water has been optimized. However, the growth of tourism has made it necessary over time to supply external supplies, mostly resorting to tankers, given the costs and technical difficulties of building desalinators or submarine pipelines to bring fresh water from the mainland ", explains ENEA researcher Marco Proposito, one of the co-authors of the study. "Our research - he continues - shows that with the sustainable use of wells appropriately located, the water needs of the resident population could be amply satisfied in periods of drought, limiting the use of tankers during large influxes of visitors". This activity of ENEA is part of the broader context of the impacts of climate change which, especially in the Mediterranean basin, may determine significant variations in both temperatures and rainfall with significant repercussions on the availability of water resources. From a study published in 2018 in Nature Climate Change in the entire Mediterranean region, temperatures on average increased by 1,4 ° C compared to the pre-industrial era and by 0,4 ° C compared to global averages, with a reduction in rainfall summer in some areas estimated at 10-30%.
