Environmental and economic analysis for the optimal reuse of water in a residential complex

• An optimization model for synthesizing residential water networks is presented.
• The model considers water reclamation and rainwater harvesting.
• Life cycle assessment methods are used to evaluate the environmental impact.
• The proposed method is applied to a case study in a residential complex in Mexico.

This paper presents an optimization formulation for designing residential water networks involving harvested rainwater and reclaimed wastewater. The design problem is posed as a multi-objective optimization formulation that seeks to balance the objectives of total annualized cost, fresh water consumption, and environmental impact. A life cycle assessment approach is undertaken for estimating the environmental impact. The seasonal dependence of the rainwater is considered in the optimization model. The design approach is applied to a case study for the city of Morelia in Mexico. The results show that significant economic, fresh water consumption, and environmental benefits can be obtained as a result of the proposed approach.