Optimal Quality Sensor Placement in Water Distribution Networks under Temporal and Spatial Uncertain Contamination

Contamination of a water distribution network (WDN) is one of the most dangerous events which may occur in accidental or deliberate conditions. The contamination spreads across the network based on the water flow and, as a result, has negative consequences on public health. In this regard, one of the most effective strategies is to install quality sensors. These sensors could reduce the damage due to detecting the contamination and applying appropriate policies. In this study, an optimization approach for quality sensor placement is presented. In this model, based on spatial and temporal uncertainty of input contaminant, a new parameter called maximum possible damage is introduced. Using EPANET as a hydraulic and quality simulator, the damage matrices are calculated for all possible values of temporal and spatial input contamination. In the following, these matrices are used in an optimization model in order to calculate the maximum possible damage. The genetic algorithm is implemented here to solve the problem.  The presented method is investigated on a case study network, and results show that this method could find the optimal sensor placement and reduce the damage caused by contamination. As an example, it can be seen that installing one or two sensors could reduce the contaminated water damage by 56% and 78%, respectively.