A modelling approach to assess wastewater reuse potential for Delhi city

Water availability is facing crisis throughout the world because of various factors viz., population growth, climate change, and rapid urbanization, leading to the requirement of treated wastewater as an additional source of water supply. However, the actual amount of wastewater that may be reused depends on many factors such as water demand, availability, cost and social acceptability, etc. In this study, a linear programming model has been developed to identify the amount of treated wastewater that may be used for various applications subject to water availability and demand constraints, taking Delhi city as a case study. The results suggest that wastewater reuse has the maximum potential in agriculture and landscape irrigation use followed by domestic and industrial applications. The framework developed in the study provides useful information for integrated planning and management of the reuse of wastewater in order to augment the existing water supply. It may be modified and used for the estimation of wastewater reuse potential in other areas with similar conditions.