Towards the integrated management of urban water systems: Conceptualizing integration and its uncertainties

Climate change and urbanization, as well as growing environmental and economic concerns, highlight the limitations of traditional wastewater practices and thereby challenge the management of urban water systems. Both in theory and in practice, it has been widely acknowledged that the challenges of the twenty-first century require solutions that address problems in a more integrated way. Although the demand for integration is obvious, implementation has proved challenging because of the complexity and uncertainty involved. In addition, the urban water literature contains a wide diversity of approaches to integration, each contribution having its own understanding of the term, as well as how to deal with the complexity that comes with it. In this article, we take a first step in supporting both decision-making and decision-makers in urban water systems integration. First, we work towards a more comprehensive perspective on integration in urban water management; one that uses and structures the variety of existing approaches. In so doing, we introduce a typology of urban water systems integration that distinguishes between geographical, physical, informational, and project-based forms. Second, we explore the implications that such integrated solutions bring for decision-makers. They will be faced with additional uncertainty arising (1) at the interfaces of previously unconnected systems and (2) from the social and institutional changes that systems integration requires. Finally, we draft three decision-making challenges that come with integration and provide some possibilities for dealing with them.