Reusing treated wastewater and biosolids in urban agriculture: Social feasibility of a decentralized approach for underserved settlements

Urban poverty and water pollution are interconnected challenges that severely impact the quality of life in cities, particularly among vulnerable populations. Wastewater generation is a significant issue associated with the expansion of informal settlements in developing countries. Given the growing interest in reusing wastewater for agriculture, this study assesses the social feasibility of introducing urban agriculture as a decentralized wastewater treatment approach in underserved areas of Colombo, Sri Lanka. A questionnaire survey was conducted in a selected underserved settlement to evaluate public willingness to use treated wastewater for farming as an irrigation source and biosolids. The results show that 62 % of participants are willing to use treated wastewater for irrigation, while only 40.4 % are open to using biosolids for fertilizer, highlighting the social feasibility of promoting urban agriculture in underserved settlements as a wastewater treatment technique. Binary logistic regression analysis and marginal analysis suggest that household size, interest in farming and motivation for farming have key influence on public willingness for use treated wastewater for urban farming actvities. The insights from this study contribute to academic discourse and offer practical guidance for policymakers and urban planners to understand the social acceptability of using agriculture as a decentralized wastewater treatment approach in urban underserved communities to promote sustainable wastewater management practices and reduce urban water pollution.