California’s Water Footprint: recent trends and framework for a sustainable transition
This dissertation presents three studies on California’s water footprint, which is defined as the amount of water required to produce everyday goods and services demanded by California consumers on a yearly basis. Such a consumption-based indicator of water use is novel, and I introduce water footprint science as an expanded reading of water that adds value to conventional approaches to understanding society’s relationship with water resources. California, as a water-limited state, presents a useful case study for examining how demands on water resources have shifted within and outside of the region through its water footprint. The Introduction section discusses the history of water use in California from a conventional perspective as well as what water footprint assessment, as an evolving science, might offer in terms of an expanded reading of water for sustainability decision making.
The first study (Chapter 2) shows that scaling water footprint assessment to the state level both illuminates California’s unique arrangement with respect to internal and external water resources and provides a basis for policy consideration at a relevant decision-making level. The second study (Chapter 3) focuses on the water footprint of California’s energy system in order to show how environmental policymaking, particularly climate mitigation policies in the energy sector, can result in maladaptation with respect to water systems and that water footprint assessment provides a useful tool for avoiding redistribution of water impacts. The third study (Chapter 4) presents a time-series of California’s overall water footprint, indicating an externalization of water footprint demands in recent decades and a decreasing of dependence on internal water resources for instate consumption of everyday goods.
The Conclusion section reflects on what water footprint assessment has thus far provided in terms of an expanded reading of water for California, and how that information might support sustainability decision making in various facets of governance. I identify shortcomings of the method and ways in which improvements can be made in the future, particularly through interdisciplinary research. Water footprint information offers important insights into California’s recent development as well as tools for developing future sustainable transitions.