In the historical narrative of Iraq, oil is often considered the most formative aspect of the nation’s development. Water has received less consideration for what has been and remains its critically important influence. Water’s historical importance in Iraq runs deep. In the 20th century, it was crucial to the making of the modern politics, to shaping social relations, and to the country’s environmental relations. Along with the effects of its two major rivers, it water scarcity also shaped many of the fears and anxieties of modern Iraqis. Focusing on the late Ottoman and early colonial period, this research seeks to evaluate the extent to which water, and its absence, has played a role in shaping Iraq. This research will specifically examine Ottoman and colonial laws regarding water management, as well as the relationship of water with health and medicine. To this end, this paper will draw extensively from missionary journals and colonial and Ottoman archives, including those related to law, environmental management, and medical record. In context of disease and sanitation, colonial and Ottoman sources come into dialogue regarding questions of science, medicine, and public health. By focusing on colonial and Ottoman law, I will examine how water has been used a means of control and governance, especially within the colonial framework. Water management was not left to Iraqis to establish; rather, it was another extension of colonial dominance that created a demand for British technology and expertise. By providing this hyrdopolitical and environmental account of Iraq’s history, this paper stands to explore the relationships between empire, colonialism, technology, and law.