Evaluation of Widespread Contaminant on Water Distribution Systems

Water distribution systems provide water supply to meet the people's demand, and it is an essential part of society. But it is also vulnerable and easy to get contaminated. Widespread contaminant can be introduced in water distribution system through accidental (e.g., rupture of water infrastructure, pipe leakage) or intentional (e.g., terrorist) acts. As a measure of water distribution contamination, the chlorine residual concentration can be used. The chlorine residual will highly decrease when a contamination happens in water distribution system. The objective of this paper is to develop a SRIQ (System Readiness Index for Water Quality) to evaluate and quantify the impact of widespread contamination on a water distribution system. The system is an expansion of a real WDS. It contains two reservoirs, four pumps, 78 pipes, and other needed fixtures. For assessment of system performance in widespread microbial contamination, EPANET software is used and SRIQ is calculated. SRIQ is predicted based on the combined assessment of water quality reliability, resiliency (time it takes to recover from a contamination), and vulnerability (how significantly the contaminant can damage the system) utilizing MATLAB toolbox. The impact of providing redundancy in pipes and reservoirs to increase the systems' reliability is also investigated. The results of this study can be utilized for improvement of water distribution systems performance.