Globally, cities face exacerbating water crises. The consequences of climate change and ongoing urban growth result in more intense water scarcity and flooding, while water pollution remains a pressing problem. Urban policymakers and practitioners have widely endorsed urban water circularity as a new paradigm to tackle these challenges. They pin high hopes for urban water sustainability and resilience on visions to combine diverse water management technologies in new infrastructure arrangements that enable a more circular water flow. This development reflects the broader dynamics of urban environmental governance in the Anthropocene, where urban environmental challenges are met with attempts to govern cities as complex adaptive systems.

This dissertation undertakes a critical inquiry into urban water circularity in practice. The main objective is to develop a more detailed and critical understanding of the political relationships between the visions of urban water circularity and the socio-technical changes in urban water infrastructures emerging in efforts to tackle urban water crises. The study aims to explore the contested governance of circular water restructuring in cities and its broader political entanglements with urban nature. To grasp the complex and situated socio-technical interactions that shape circular urban water restructuring, the study focuses on the case of Los Angeles. Three sub-cases are examined in detail: wastewater recycling (Chapter 2), stormwater capture (Chapter 3), and landscape water conservation in residential gardens (Chapter 4).

The main conceptual focus of this dissertation is on the political role of technology in endeavors to realize ideas of urban water circularity. The study employs and refines critical debates on urban infrastructures and in science and technology studies to analyze the technopolitics of infrastructural change in emerging circular water cities. This focus highlights how actors pursue political goals in processes of infrastructural change through technology.