Accounting for Source Location on the Vulnerability Assessment of Water Distribution Network

The vulnerability of water distribution networks (WDNs) to water-main breaks is used for prioritizing pipes in the network for maintenance planning. In this paper, a parameter of graph theory, algebraic connectivity (AC), is employed as a vulnerability metric for WDNs. The change in the magnitude of AC of the networks due to the removal of pipes was found to have a strong correlation with loss of robustness of the WDNs or the size of the network being isolated by the water-main breaks. However, because AC is a topographic measure of graphs, the effects of the location of water sources are not accounted for in ranking through the change in AC. A virtual network is proposed here to overcome the limitation and to move the centrality of the network to the pipes connecting to the water source. The resulting AC based ranking is found to have a correlation with hydraulic impact factor-based ranking of the pipes of WDNs.