ABSTRACT Graphical abstract showing wastewater from industry and homes treated and reused for irrigation, with flow from sources through treatment to reuse in fields. The world faces water scarcity in the modern era, exacerbated by increased demand for agricultural production. The future rise in population will further increase demand. Such a scenario underscores the need to find sustainable alternatives to conventional freshwater sources. One solution in such scenarios is the use of treated wastewater in agriculture. This paper provides a review of the benefits, risks, technological advancements, and knowledge gaps associated with the idea of reusing treated wastewater in irrigation to improve water conservation, enhance soil fertility, and support sustainable food production. There are risks as well when using treated wastewater, including health concerns from pathogen contamination, soil degradation, and the accumulation of heavy metals in crops. To mitigate these risks, controlled irrigation methods such as drip and subsurface irrigation, along with the use of preventive measures, can be helpful. Knowledge gaps have been identified in the context of long-term soil-health impacts, crop safety, and the overall feasibility of the idea for small-scale farmers with limited resources to invest. The paper concludes that further research and development are needed to realize the long-term benefits of the concept.
Singh et al. (Mon,) studied this question.