Reducing the environmental footprint is our commitment, this type of water includes different kinds of liquid waste such as domestic drainage water and services, industrial by-products and rainwater connected to the municipal network. The population increases significantly and with it the demand for the liquid element, being able to reuse it again without causing any risk to environmental resources. Our proposals are based on the cost analysis of the complete life cycle of the infrastructure (construction, operation and maintenance) guaranteeing the sustainability and efficiency of the system.