We-Need - Water Needs, Availability, Quality And Sustainability Final Conference And International Workshop - 12, June 2019 - Politecnico Di Milano (Italy)

Quality and availability of groundwater resources are nowadays endangered by several factors, including over-exploitation, and contamination by anthropogenic activities.
WE-NEED is a project funded under the Joint Call 2015 developed by the Water Challenges for a Changing World Joint Programme Initiative (Water JPI). The project was recently completed under the coordination of the Politecnico di Milano (Italy) with participation of international partners from Israel (Weizmann Institute of Science), Portugal (University of Aveiro), and Spain (Polytechnical University of Catalunya). The project also relied on the collaboration with institutions dealing with groundwater protection and management (ARPA Emilia Romagna, Consorzio Irrigazioni Cremonesi, Consorzio di Bonifica Dugali, Naviglio, Adda Serio).

WE-NEED has contributed to developing new management strategies to sustainably assist the use of two common groundwater (GW) resources, i.e., pumping wells and natural springs, a major focus being on the risk posed by Emerging Contaminants (ECs) to water quality. ECs (including, e.g., pharmaceuticals, personal care products and engineered nanomaterials) are a source of growing concern in modern society, with severe implications to risk management in the water-aquifer environment. WE-NEED embeds information on transport and fate of ECs in GW within modern probabilistic risk assessment strategies for management, to increase certainty through quantification of risk. WE-NEED considers pilot application to two sites representing differing but complementary realities, i.e., the Bologna and Cremona aquifer systems, located in Italy. The main objective in the Bologna site is the assessment of the risks to which the set of pumping stations currently employed for freshwater withdrawal from the deep aquifer body can be exposed. The focus in the Cremona region is on the protection of the system of natural springs which constitute a unique ecosystem and a markedly valuable resource in the area. The work plan has been structured across five main tasks: (1) hydrogeological characterization of the two sites; (2) development of probabilistic flow and transport models of the sites; (3) assessment of fate and transport of representative ECs in laboratory experiments; (4) assessment of ecotoxicity of ECs mixtures in laboratory experiments; (5) development of a Groundwater Risk Management model and its application to the two field sites. Results of Task 1 include the set-up of fully three-dimensional hydrogeological models of the two sites. These are obtained through a stochastic approach embedding conceptual model as well as model parameter uncertainties. Probabilistic reconstructions of the subsurface architecture have been produced on the basis of various conceptual models which can be employed to characterize complex aquifer systems of the type we analyze. Such conceptual models are conditional on available data and are then used as input to Task 2. The latter has been accomplished upon relying on a numerical Monte Carlo (MC) framework. Main modeling goals include the probabilistic distributions of (three-dimensional) (a) time-related capture zones for the extraction wells in the Bologna site and (b) time-related recharge regions of the major natural spring in the Cremona area. These results inform Task 5 and enable local stakeholders to assess the probability that the system is subject to failure, the latter being quantified, e.g., in terms of pumping well contamination and spring depletion. Results from Tasks 3 and 4 have enabled to assess the behavior of representative contaminants in the systems analyzed and to assess the related ecotoxicity. These are used to inform the modeling activities in terms of (a) parameters associated with chemical transport and (b) concentration levels threatening proper ecosystem functioning. Task 5 was focused on development and testing of a Groundwater Probabilistic Risk Model (GPRM) aimed at assessing (and preventing) negative effects of water resources management and exploitation. The main environmental performance metrics to ensure good quality of the water produced in the Bologna well fields are the hypothetical detection of ECs at the wells as well as the time taken by these chemicals entering the groundwater system from regions associated with differing land use to reach the wells. Otherwise, the application of the GPRM to the Cremona site has been devoted to identifying new sustainable groundwater management strategies for the preservation of natural springs. As such, the main element of concern considered to ensure natural spring preservation is the water level at the springs, which can be affected by pumping for agricultural/industrial use. The complete set of WE-NEED deliverables can be downloaded from the Open Data & Open Access Water JPI platform.