A Review on Methods for Economic Analysis of Leakage in Water Distribution Networks

As the main component of real water losses, leakage afflicts most water networks worldwide; even the best Water Distribution Networks (WDNs) have leakage in their network infrastructure. Several methods and strategies have been developed for leakage reduction and performance improvement in WDNs. In practice, leakage control strategies, including active leakage control, passive leakage control, pressure management, and infrastructure asset management, are performed by water utilities to reduce leakage. The main question is, which of these leakage management strategies are the most appropriate for a specific WDN? The answer to this question is obtained by analyzing the economic level of leakage (ELL). In fact, the essential component of a leakage control strategy is that its target is set in terms of the economic level of leakage (ELL). This paper provides a comprehensive review of the estimation of the ELL at different time frames, including short-run, long-run, and sustainable in WDNs. In addition, a procedure to estimate the ELL is proposed according to the conditions in each network or the relevant water utilities. Results of this review could be a valuable reference resource for practitioners and researchers dealing with non-revenue water in WDNs.