Water reuse has proved to be an efficient way to reduce freshwater demand and wastewater generation in process industries. In this paper, a methodology for minimizing the costs associated to water management in batch process industries is presented. This work is based on a previous methodology for freshwater demand minimization, which has been extended to the economical aspects of water management: cost associated to freshwater supply and conditioning, wastewater treatment and disposal, as well as water reuse network investment and operation costs. Water reuse network design is optimized from the economical point of view, minimizing the operation and investment costs associated to the water use.