Management of the drinking water supply chain under climate change: new threats require new strategies

Direct consequences of climate change are represented by both the increase of air and water temperature and the alteration of precipitation patterns, characterized by longer droughts periods and more intense precipitations. These modifications impact on water quality, affecting the presence of microorganisms, natural organic matter (NOM), and contaminants of emerging concern (CECs). Such quality parameters are indeed crucial to provide consumers with safe drinking water, making the understanding of their variation patterns of paramount importance, to tune proper treatment schemes to minimize the human health risk. The goal of this work is to develop a holistic approach to increase the overall preparedness of the drinking water sector with respect to the need of upgrading the drinking water supply systems, comprising the plants and the distribution networks. Concerning CECs and NOM removal, the adsorption process was assessed by: (i) meta-analysis of literature isotherm data to predict CECs removal extent, and (ii) lab experiments to optimize NOM removal with respect to the type of activated carbon and the EBCT value. Then, an analysis of full-scale monitoring data from an Italian Water Utility was performed to support operators in the correct management of distribution network, identifying the most vulnerable monitoring locations with respect to both microbiological and chemical risk.