Cellular Automata Modeling Framework for Urban Water Reuse Planning and Management

Water reuse provides a sustainable approach to balance water supply and demand in urban areas, and reclaimed water can be used for nonpotable applications to reduce demands on freshwater sources. Construction of a secondary network is required to distribute reclaimed water. Implementing water reuse projects on a wider scale is challenged by the need for communitywide public acceptance and adoption, which may be a dynamic and adaptive process. The adoption of new water infrastructure can drive hydraulic conditions in both the reclaimed network and an existing drinking water network. This research develops a dynamic modeling framework using a cellular automata (CA) approach to simulate consumer adoption of reclaimed water. The framework couples the CA model of consumer adoption with water distribution system models of the drinking and reclaimed water systems. Emergent distribution system hydraulic conditions are simulated, and the capacity utilization and system performance are evaluated as consumers adopt water reuse. The Town of Cary, North Carolina, is used as case study to develop and demonstrate the modeling framework. The CA parameters and rules are developed and validated using data about the addition of new accounts for the period 2001-2012. Projected water reuse adoption is simulated in Cary for the period 2012-2030, and impacts on the existing drinking water infrastructure and planned reclaimed water infrastructure are evaluated. (C) 2016 American Society of Civil Engineers.