Intermittent Urban Water Supply with Protection of Consumers' Welfare

Intermittent operation of water networks is prevalent in many developing countries. It is a practical method to continue operation of water distribution networks (WDNs) during unexpected water shortages. Implementation of intermittent water supply compels consumers to withstand periods of interrupted water supply. Intermittent operation increases operating and maintenance costs attributable to the damage of pipes and valves caused by water pressure fluctuations. This paper considers consumers' welfare and system depreciation simultaneously in a multiobjective optimization model for intermittent water supply in WDNs. The objectives of the optimization model are the improvement of water supply resiliency and the maximization of the mechanical reliability of WDNs. The optimization model is solved by means of the honey-bee mating optimization (HBMO) algorithm linked to WDN hydraulic simulator software. The model's performance is tested with several shortage scenarios in two different WDNs. The calculated results show the optimization model's capacity to determine optimal values of water supply resiliency, and demonstrate that consumers' welfare may conflict with the objective of mechanical reliability, giving rise to an optimization possibility tradeoff frontier.