This paper examines the sociotechnical imaginaries shaping the development, retrofit, and multiple uses of water infrastructure in response to crisis. Focusing on Morris Dam, located on the San Gabriel River in Los Angeles County, I ground my analysis in a case that highlights how the interactions between professional engineering and scientific practice, political aims and goals, and environmental conditions shape infrastructural form and function. Analysing three different phases in the infrastructure’s lifespan, I argue that infrastructures exist in and beyond their initial functions as metabolic conduits, as they take on new meanings in relation to shifting social, political, and environmental crises. In the first phase, I focus on the sociotechnical imaginaries and forms of politics that take shape around the development of Morris Dam as a modernization project. In the next phase, I draw attention to the unintended configurations of science, nature, and naval weapons development that emerged at Morris Dam in the mid-20th century and continued through the Cold War. The final phase examines the retrofitting process that re-modernized the dam as a technology to advance water resources sustainability and resilience in the region. Together, I use these different forms of infrastructural relations to illustrate how malleability works as an infrastructural feature and political process enabling infrastructural resilience and attachment to changing sociotechnical imaginaries over time.