Prioritising wastewater treatment strategies using single-value neutrosophic Topsis

The focus of this research was on prioritising strategies to mitigate the adverse effects associated with the construction of urban wastewater treatment plants (WWTPs), specifically during the critical study phase. Topsis (technique for order preference by similarity to ideal solution) – a multi-criteria decision making (MCDM) methodology – was employed. A significant contribution of this work is the integration of neutrosophic concepts with MCDM to effectively manage imprecise information, uncertainties stemming from human consciousness and potential unforeseen changes crucial for future planning. The first part of the study was an environmental impact assessment of the wastewater treatment system, establishing nine criteria categorised into natural resources, human health impacts and economic conditions. To address negative consequences during construction and operation of the WWTP, three strategic alternatives were proposed: advanced sludge management, green space development and stringent wastewater leakage control. Neutrosophic Topsis analysis highlighted sludge management as the most pivotal strategy for minimising detrimental effects in the foreseeable future. Furthermore, an evaluation of criteria importance identified specific factors with the most significant influence: control of unpleasant odours, mitigation of pathogen dispersal and the economic valorisation of both treated wastewater and derived sludge. This work offers a valuable decision making tool for sustainable urban wastewater management.