Evaluating the multi-dimensional resilience of water distribution networks to contamination events

Recent contamination events in water distribution networks (WDNs) suggest the need for resilience strategies to address the uncertainty of contamination intrusion. Resilience-based decision-making requires a resilience evaluation process. However, the suggestions on resilience options can vary with the definition of the system's functionality considered in the resilience evaluation. Thus, this study characterized resilience and its attributes (i.e., robustness, loss rate, recovery rate, failure duration, and recovery completeness) in multiple functional dimensions for a WDN to contamination events. The resilience evaluation was performed using a resilience measure based on a time-dependent functionality variation during contamination events. This study considered the functionalities in four dimensions: the contaminated node, compromised demand, biodegradable dissolved organic carbon concentration, and consumed mass. The hydraulic and water quality models were simulated using EPANET-MSX to evaluate the functionality variation under bacterial intrusion events. The results noted that the resilience levels significantly varied with the functional dimensions and relatedness and contamination event conditions. The results also identified that different profiles of resilience attributes could characterize similar levels of multi-dimensional resilience. The findings suggest insights on incorporating the concept of multi-dimensional resilience in decision-making processes, therefore achieving the goal of improving the overall resilience of the system in diverse aspects of functionality.