Cost Gradient–Based Assessment and Design Improvement Technique for Water Distribution Networks with Varying Loads

A gradient-based network assessment is proposed as a way to understand and improve the cost and hydraulic performance of distribution networks. It seeks to reduce the computation time of optimizing water distribution networks with varying demands by using a sequence of shorter time cycles to approximate a fuller range of costs. To allow system evolution, diameters are adjusted after each cycle according to anticipated capital, energy, and damage costs. Accounting for risks of low- and high-pressure hydraulic failure not only adds needed redundancy to the network, but also helps guide the gradient search. The method was applied to the well-known network of “Anytown.” Results indicate that the technique can be effectively applied to different scenarios and generate robust solutions. Furthermore, its lower computational intensity should facilitate its application as part of a broader optimization process and thus better enable the assessment of more storage, pumping, and control alternatives.