Prioritised rehabilitation of water distribution networks using dissipated power concept to reduce non-revenue water

This paper presents a new prioritisation approach to the problem of rehabilitation of water distribution systems. It consists in a algorithm that, based on the resilience index and on the unitary power concepts, selects the most important pipes to be replaced in order to achieve two main objectives: first, to reduce loss of water due to leakage by decreasing and levelling pressures along the entire network; second, to reduce the dissipated energy in the system, making it more efficient and reliable. Additionally, the implemented algorithm finds profitable rehabilitation schemes and allows the identification of the appropriate point at which, according to the economic and hydraulic criteria established by the user, the process of replacing pipes should be stopped. This paper includes three case studies - one hypothetical and two real water distribution systems - in which the algorithm was tested. For these networks hydraulically and economically near-optimal rehabilitation schemes were achieved.