The aim of this dissertation is to assess factors that contributed to the survival or failure of Roman water management infrastructure and practices in the eastern Mediterranean, between Roman antiquity and the early medieval period (c. 0 - 800 CE). Why did some Roman water systems survive for centuries, even until today, while others collapsed after only a few decades of functionality? Individual components of Roman water infrastructure are well described by engineers as technological artifacts. Less understood are the factors that contributed to the resilience or fragility of Roman water systems in late antiquity. These include physical or natural factors, such as climate and geology, but also politico-administrative priorities, and socio-cultural factors, such as the perceived value of monumental architecture or preferences for drinking water sources. After a review of scientific climate proxies for the Levant, which was more climatically susceptible to water scarcity than other areas of the empire, Jarash is introduced as a case study that identifies infrastructural responses to climatically induced water stress in Northern Jordan after the fifth century CE. However, because similar adaptations are visible in areas of the empire with very different climate trajectories, it is posited that socio-cultural and administrative shifts were more important for the evolution of water systems in late antiquity. Procopius is adduced as a lens, understudied until now, through which we can view shifts in late antique urbanism and the trajectory of the state's interest in water infrastructure, as they are presented in a conservative text of the sixth century. The last chapters offer a detailed analysis of the literary, epigraphic, and archaeological remains of urban water systems in the late antique Eastern Mediterranean in order to demonstrate the surprising diversity, longevity, range, and impact of Roman water systems in cities after antiquity, beyond the traditional seventh-century boundary for the survival of Roman cities in Byzantium.