Reliability Assessment of Water Distribution Networks Considering Mechanical-Hydraulic Behavior Using Informational Entropy

This paper presents a new weighted entropy-based measure for assessing reliability of water distribution networks. The proposed methodology considers both of mechanical uncertainties (probability of pipe failure) and uncertainties due to hydraulic parameters (flow in pipe) simultaneously. In this methodology a penalty function is defined for different links of the network based on their probability of failure in the specified hazard scenario. This penalty function is inserted in the hydraulic entropy function of the network in an appropriate manner so that the effect of mechanical behaviour of links is taken to account in the network’s entropy. In this manner the amount of supply loss due to absence of each link in the network is incorporated in the corresponding penalty function. Using some sample networks, it is shown that on the basis of the proposed entropy-based index the optimum hydraulic layout for designing a new system, or for finding the best mitigation plan against different natural hazards like earthquake can be chosen.