<p>This article revisits the relationship between water and power in Ptolemaic Egypt, focusing on the Fayum, a highly developed waterscape. Traditionally seen as an example of Wittfogel’s “hydraulic state,” where centralized power dominated resource management, our evidence challenges this view. Using papyrological records, this study explores the complex interplay between the Ptolemaic bureaucracy and local actors, revealing a nuanced governance model. The Ptolemaic state initiated large-scale infrastructure projects to transform the Fayum into an agricultural hub, but the day-to-day management was largely decentralized. Local communities, including village elders, royal farmers, and shepherds, developed collective action institutions to maintain irrigation networks, allocate land, and manage pastures. These bottom-up arrangements coexisted with, and sometimes complemented, the top-down administrative framework. The findings highlight a polycentric governance structure where state and communal institutions were interdependent. This challenges the prevailing dichotomy between hydraulic states and decentralized resource management, showing that even in strong managerial states, local agency played a critical role. By shedding light on these dynamics, the study redefines the water-power nexus in historical contexts and underscores the significance of local knowledge and cooperation in managing complex irrigation systems.</p>