Abstract: This paper develops a political-industrial ecology approach to explore the urban water metabolism of Los Angeles. Conventional approaches to quantify urban carbon footprints tend to “black box” methodologies that guide the carbon emissions calculus and the social, political, ecological, and economic processes that perpetually reshape nature-society metabolisms. To more fully delineate the water supply metabolism of Los Angeles, this paper combines theory and method from urban political ecology and industrial ecology. This approach offers valuable insights into the spatiality of material metabolisms and the socio-political processes reshaping the relations between nature and society.