Urban water cycle and services

The existing urban water cycles and services are crafted by the co-evolution over time and space of natural and anthropogenic systems. Those water-human systems interactions (e.g., water uses and related services) frame the different characteristics of supply and demand across the world. As a result of the preceding point, it is important to understand the relationship between competing uses, existing resources, and infrastructure requirements, as well as the subsequent variability in costs and prices, which becomes more complex in an urban context. The worldwide differences in water allocations and wastewater management tendencies, which depend to a large extent on climatic, topographical, and socioeconomic conditions, highlight the discrepancies in terms of inherent costs to achieve a sustainable water future and fulfil the sustainable development goals. To understand those differences, we present urban water worldwide trends, through key data sets, outlining water risk, sectoral characteristics (i.e., differences in water withdrawals), and water supply and sanitation access. In the end, an integrated view of managing the multiple water-related services seems desirable, highlighting a need for innovative governing, technical, and financing approaches.