The Concept and Realm of the Principle of Equitable and Reasonable Utilization of Shared Water Resources: From the Perspective of International Law

One of the important principles of international water law is the Principle of Equitable and Reasonable Utilization. According to this principle, any Watercourse State is eligible for an equitable and reasonable share in the constructive use of the shared water resource. The allocation of states' rights in using shared water resources has long been based on the multi-dimensional and complex definition of fairness. The main questions to which this research intends to answer are as follows: what is the concept and realm of the principle of equitable and reasonable utilization in the international law and procedure and how was the process of its changes? This principle, as the main basis and component of the international water law system, is considered a rule of the customary international law and is included in various international instruments. The described principle, along with other principles ruling in this field, can create a lawful system for the states and control the disputes between the states in shared water resources management. In this research, by using library and internet resources and international instruments, and using a descriptive-analytical method, the concept and realm of the principle of equitable and reasonable utilization will be studied.