A water-sensitive circular economy and the nexus concept

The transition to a Circular Economy requires changes throughout whole value chains and across sectors. In this context, the basic conceptual framework of the Nexus approach, that of looking at complex systems as a whole, with special attention to interactions and cascading effects, is a valuable conceptual lens and a powerful computational framework to investigate opportunities and manage challenges when re-wiring the economy in a more circular fashion. Including Circular Economy principles such as waste (re)utilization within a nexus approach would allow different stakeholders linked though the Water-Energy-Food-Environment (WEFE) nexus to identify and exploit circular economy opportunities. This is especially true in a Circular Economy approach with water at its centre. This chapter presents how wastewater and its embedded resources (water, energy, materials) could become raw material for other processes within sectors such as agriculture, industry or the energy sector. It also briefly presents indicative circular management solutions (technologies, tools, business models, marketplaces, policy instruments) that will be required to re-design and re-configure nexus inter-dependencies within a CE context.