California has been heralded as a beacon of agricultural production and productivity, yet its groundwater crisis is a warning of its impending collapse. In this paper, we argue that policies like California’s Sustainable Groundwater Management Act reinscribe the settler state, even as they aim toward environmental sustainability. Drawing from Indigenous feminist scholarship on water and frontier processes, our methodology traces settler colonialism materially and discursively through the movement of water. First, we analyze hydraulic engineering discourses at the turn of the 20th century to illustrate how racial logics were key to producing irrigation—and the broader project of white settlement—as ostensibly benevolent processes of improvement. We then highlight how turn-of-the-century legislation was central to producing agriculture as a site of accumulation by dispossession through the production of settler forms of property and relations with land and water. Finally, we consider groundwater overdraft as a vertical frontier. Thinking with water as an analytic, we study the nexus of relationships that inscribe settler water infrastructures as normative, demonstrating their role as frontier processes within a settler colonial present. Our analysis shows the necessity of dismantling settler modes of sustainability and centering and supporting Indigenous sovereignty.