Losses in Water Distribution Systems: A Complexity Theory Perspective

Water Distribution Systems (WDSs) have losses, which are difficult to be eliminated due to the complex socio-technical nature of these systems. This paper presents a systematic review of the literature on losses in WDSs, which addresses two questions: which are the factors that influence the complexity of WDSs, having an impact on the losses of water? How do the methods used to control losses in WDSs account for complexity? We assumed that to be compatible with the nature of WDSs, the loss control methods should account for five attributes of complexity. Twenty-one factors that influence these attributes were identified from 49 selected papers, based on a content analysis. Non-linear interactions were the attribute most frequently accounted by the methods (36.5%), and none of the methods simultaneously accounted for all the five attributes. The review also supported the development of a model of the relationships between the factors that influence the complexity attributes. This model is a basis for the analysis of the impacts of actions for tackling losses.