A Historical and Futures-Oriented Analysis of Iran–Afghanistan Water Disputes over the Helmand River: From the 1973 Treaty to the 2036 Horizon

Abstract

The dispute over the Helmand River, as one of the longest-standing and most complex transboundary water disputes in West Asia, has cast a shadow over relations between Iran and Afghanistan for more than a century. Employing a descriptive-analytical method and an interdisciplinary approach integrating political science and international law, this study draws on historical analysis, documentary analysis, and scenario-based futures studies to examine the origins, trajectories, and dynamics of Iran–Afghanistan water disputes from 1920 to 2021 and to explore their prospective development through the 2036 horizon. The findings indicate that the 1973 Helmand River Water Treaty, despite its relatively comprehensive technical provisions at the time of its conclusion, lacks sufficient effectiveness to guarantee Iran’s water rights under current conditions due to the destruction of water-measurement infrastructure at Dehrawud, ambiguity surrounding the concept of a “normal water year” in the context of climate change, the absence of a binding dispute-settlement mechanism, and its lack of conformity with the 1997 United Nations Convention on the Law of the Non-Navigational Uses of International Watercourses. Afghanistan’s extensive dam-development program, particularly the Kajaki, Kamal Khan, and Pashdan dams, can be analyzed within the theoretical framework of “hydro-hegemony,” given its disregard for the principles of equitable and reasonable utilization and the obligation not to cause significant harm, and constitutes a serious threat to Iran’s water and national security. Scenario analysis indicates that, among four plausible scenarios—sustainable cooperation, a security crisis, continuation of the status quo, and internationalization of the crisis—the security-crisis scenario is the most probable through the 2036 horizon, given the intensification of drought, the completion of Afghanistan’s dam projects, and the continuation of Kabul’s unilateral approach. Accordingly, the article proposes a five-pillar model for the sustainable management of the dispute, based on joint institutionalization, revision of the 1973 Treaty, development of mutually beneficial bilateral projects, transparent joint monitoring, and strengthening of enforcement mechanisms.