Heightened interest in recent years in water and its management in the Aegean and wider Mediterranean world has meaningfully broadened discussion beyond the purely practical, allowing us to appreciate the ambition of many projects, their power as symbols of shared identity, and their ability to transform urban and religious landscapes. The labor and materials invested in these water conduits, dams, drains, and fountains in many cases warrant the appellation of “monumental.” Thanks to this line of inquiry, the potent symbolism of waterworks beyond the more well known aqueducts and fountains of Roman Greece and Asia Minor are increasingly appreciated, as are the water management systems of the Bronze Age Aegean. Engagement with water management and the pre-Roman Greek poleis in these terms has been more uneven. Water management projects associated with historical figures, particularly the building programs of tyrants like Peisistratos, have received a great deal of attention, as well as the sacred topographies of regions like Attica and the Corinthia. Outside these well-documented contexts, the symbolic potential of particularly exceptional constructions have tended to preoccupy scholarship, as at Alyzia where the remains of a monumental stone dam were found, endowed with a stone-carved lateral spillway and built of a sophisticated tightly packed boulder masonry style. Yet the Alyzia dam is a unicum, a uniquely local response to a specific circumstance, and the varied climates and topographies settled by the Greek diaspora required varying approaches to water management. This paper considers whether common practices can be identified within the comparatively understudied North Aegean region, using the islands of Thasos and Samothrace as case studies, and considers how water management projects could become arenas for monumental display beyond the purely practical. The importance of monumental water management projects to city-states’ civic identities is well illustrated by Herodotus’s (3.60–63) description of the greatest achievements of the Samians under Polycrates. In addition to the Heraion, a peripteral temple more in keeping with popular conceptions of monumental architecture, the historian includes the aqueduct built by Eupalinos, constructed by two teams boring from opposite sides of a mountain, and a massive deep-water mole girding the ancient city’s harbor. Arguably the most famous mastering of water during the Classical Period comes from the North Aegean, with Xerxes’ canal cut through the Chalkidiki (Hdt. 7.22–24; Thuc. 4.109) being so ambitious that their actual existence was doubted only centuries later. While the astonishing scale and ambition of these works symbolized the ambition, and to some extent hubris, of tyrants and kings, every Greek community wrestled with water management, and could celebrate its mastery. The climate of the North Aegean and the topography of the Thracian coast and islands created a unique set of challenges to master. Cutting across Greece from southern Albania to Thessaly, the Pindus Mountain range creates a relatively dry southeastern Greece, while northern regions such as Macedonia and coastal Thrace are comparatively well-watered. The coast and islands from the Thessaloniki-Larisa region east have historically enjoyed greater precipitation levels, with drier summer months and rainier winters, average precipitation rates increasing as one nears the Troad. Greater annual rainfall necessitated more significant interventions, although local needs varied considerably. The islands of Thasos and Samothrace are a case in point. Samothrace is defined by Mount Saos, whose peak exceeds 1,600 masl, and a soil that retains little water thanks to shallow groundwater aquifers and weathering resistant rock, leading to seasonal runoff and flashy streams systems that in turn demands management systems geared towards episodic flood events. While receiving similar rainfall, Thasos’ milder elevation and large number of aquifer-fed springs required interventions to counteract rising groundwater as much as surface runoff. These localized demands necessarily led to differing approaches by the Thasians and Samothracians, but within the context of a region needing extensive water management systems. The question becomes, then, when the display of such systems publicly in the context of civic and religious space moves beyond the practical.