Optimization of water quality sensors placement in water distribution networks to detect contamination entrance from several nodes, simultaneously

Water distribution networks are critical infrastructure that should be protected against deliberate and accidental attacks. The quality of water is investigated in the treatment plant; however, it can be significantly changed during transmission from the treatment plant to consumers. The contamination entry place is unpredictable and contamination can be entered from several locations simultaneously. Water quality sensors and the pollution warning system can detect the contamination. The alarm system function is depends on the number of sensors installed on the network and their location. In this research, contamination is entered in one or two nodes and the number of sensors installed in the network is one to four. In addition, four objective functions were considered to optimize the locations and the number of sensors. The network was analyzed dynamically. For each sensor placement, the consumed contamination water and the contaminated area are evaluated.  The method was able to identify the best location for the different objective function.