Although they originate in Tibet, the Indus and Sutlej rivers eventually flow into India and Pakistan, where they provide essential water resources for millions of people. Questions have been raised regarding the legality of blocking certain rivers as a result of recent efforts undertaken by China to construct dams and divert water systems. With a particular emphasis on the Helsinki Rules and United Nations agreements, this article takes a look at the international legal framework that governs rivers that are shared by many parties. This document provides an explanation of the concepts of equitable and reasonable use, the requirement to avoid causing severe harm, and the obligation to notify and discuss with states that are located downstream. Through this discussion, it is made clear if China is legally able to restrict river flows from Tibet in accordance with these norms and conventions.