Transboundary Waters and the Obligation of No Harm: The Tigris and Euphrates as a Model

Abstract

The principle of "no harm" constitutes a cornerstone of international law governing the management of transboundary water resources, as articulated in the 1997 United Nations Watercourses Convention. However, its application in the context of the Tigris and Euphrates disputes faces significant challenges. Iraq relies on the Tigris and Euphrates rivers as lifelines for agriculture, drinking water, and ecosystem sustainability. Yet, Turkish dam projects, such as the Ilisu Dam within the Southeastern Anatolia Project, have substantially reduced water flows, leading to the desiccation of southern marshes, declining agricultural productivity, and threats to food and environmental security. These impacts constitute a violation of the no-harm principle, which obliges states to prevent causing significant harm to other riparian states.Legal challenges include the absence of a precise definition of "significant harm," Turkey’s non-ratification of the 1997 Convention, and the lack of binding regional agreements. Additionally, political tensions among Iraq, Turkey, and Syria represent prominent obstacles, while Turkey’s economic priorities favor its developmental interests over the shared interests of the Tigris and Euphrates riparian states. Other challenges include the lack of shared hydrological data and the absence of environmental impact assessments, which undermine the effectiveness of the no-harm principle. Furthermore, climate change exacerbates the complexity of managing transboundary water resources.