Emergency Household Water Treatment for Conflict-Induced Supply Disruption: A Case Study of Multi-Contaminant Raw Water in Mykolaiv, Ukraine

Damage to urban water supply infrastructure can rapidly compromise access to safe water and force households to rely on alternative sources of uncertain quality. This study presents a case-based assessment of water quality and emergency household-level treatment options in Mykolaiv, Ukraine, following conflict-induced disruption of the centralized water supply system. Water samples collected from selected groundwater and distribution-network points were analyzed for physicochemical, organoleptic, and microbiological indicators, including total dissolved solids, hardness, sulfates, chlorides, iron, permanganate oxidizability, total microbial count, and E. coli. The results showed elevated mineralization, increased sulfate and chloride concentrations, high hardness, organic load indicators, and episodic microbiological contamination in several samples. A low-cost four-stage household treatment procedure combining chemical oxidation, thermal treatment, sorption, and short-term preservation was evaluated as a preliminary emergency approach. The procedure improved odor, taste, hardness, iron content, permanganate oxidizability, and microbiological safety; however, it did not fully reduce total dissolved solids, sulfates, or chlorides to drinking-water standards. Therefore, the treated water should be considered non-potable and suitable mainly for limited domestic and hygienic uses unless additional desalination or blending is applied. The study highlights both the potential and the limitations of simple household-level interventions under emergency water supply disruption and emphasizes the need for decentralized treatment support, monitoring, and long-term infrastructure recovery.