Resilience/Availability Analysis of Municipal Water Distribution System Incorporating Adaptive Pump Operation

In last three decades, the reliability of water distribution systems (WDSs) has become a major concern, not only for water utilities and academic research communities, but also for society as a whole. Notable research has been conducted on the reliability/availability of WDSs, however, little attention has been paid to quantify the impact of adaptive operations as a response to system failure to enhance the resiliency of WDSs. Here, resilience is defined in the general sense as the ability to recover from a failure to a satisfactory state. In practice, if a system fails to supply water with adequate pressure, the water utility would take action to respond. Adaptive actions include switching on additional pumps as a short-term remedy or maintaining a higher water level in storage tanks as a long-term strategy to satisfy system pressure when a system experiences abnormal conditions. Here, a Monte Carlo simulation based framework for the resilience analysis of WDSs is implemented, considering the impact of adaptive pump operations and isolation valve locations. The framework consists of four steps: (1) random event generation for nodal demand fluctuations and pipe breaks; (2) identification of isolated segments based on valve layout; (3) hydraulic simulation with regular and adaptive operations; and (4) identification of responses and the evaluation of system resilience/availability. The proposed methodology is applied to a mid-sized WDS and results show that adaptive pump operations improve system resilience with a moderate pumping cost increase.