A Water Line Network Failure Application of Network Design Problems

Abstract

This study investigated a water supply recovery problem involving municipal water service piping. The problem consisted in recovering full service after network failure, in order to rapidly satisfy all urgent citywide demands. The optimal recovery solution was achieved through the application of so-called network design problems (NDPs), which are a form of combinatorial optimization problem. However, a conventional NDP is not suitable for addressing urgent situations because (1) it does not utilize the non-failure arcs in the network, and (2) it is solely concerned with stable costs such as flow costs. Therefore, to adapt the technique to such urgent situations, the conventional NDP is here modified to deal with the specified water supply problem. In addition, a numerical illustration using the Sendai water network is presented.