Small-scale modelling of water quality evolution to anticipate potential impacts on biocide treatment discharges in the context of climate change – Biocide-WATCH

The Biocide-WATCH project addresses the impact of global warming (GW) on water quality, focusing on how these modifications will affect the formation of disinfection by-products (DBPs). The climatic changes, combined with human activities, intensify eutrophication, degrade water quality, and enhance the production of natural organic matter (NOM), both autochthonous (from aquatic sources) and allochthonous (from soil erosion and leaching). The degradation of water quality affects the processes and efficiency of water treatment, particularly disinfection, which is essential for human consumption and industrial uses. The project aims to secure water resources by analyzing how GW-induced changes in water quality influence the formation of DBPs. DBPs result from chemical disinfection, and their formation and diversity may increase as water quality deteriorates. Existing studies focus on only a few DBPs, like trihalomethanes, and fail to account for emerging DBPs due to limitations in analytical methods. The project addresses this gap by developing an integrated approach, combining advanced modeling of NOM, new analytical methods for DBPs, and predictive tools leveraging artificial intelligence (AI). The project involves six key tasks: collection of natural water from three rivers in France, and experimental design and modeling of climate change-impacted OM, collection and analysis of historical water quality data to identify potential changes and deployment of probes for real-time monitoring of OM dynamics and key parameters, perform comprehensive OM characterization using advanced analytical techniques such as fluorescence spectroscopy, and FT-ICR MS, development of multi-residue techniques for volatile and polar DBPs and non-targeted screening for unknown DBPs, studying the kinetics of DBP formation under varied laboratory conditions, and creating AI-based tools to predict NOM and DBP evolution. These efforts aim to enhance understanding of how climate change modifies NOM and leads to new DBP risks, contributing to better environmental risk management and water treatment strategies.