With a growing human population and changing lifestyles, the claim for freshwater and climatic variability make water supply and demand problematic and uncertain. The growing demand and thereby competition for shared water have led to many international conflicts, political instability, and even acute violence in some regions. There are many worldwide examples of interstate conflicts like Turkey, Syria, and Iraq have fought over the Euphrates-Tigris. South Asia is a region of both plenty and scarcity of water. The four major rivers are the Indus, the Ganges, the Brahmaputra, and the Barak (Mehgna), also known as the IGBM basin. India is centrally located in South Asia, its borders touch with almost all South Asian countries, and as a result, India shares its rivers with its neighbors, Bangladesh, Pakistan, and Nepal. Pakistan and India share the Indus River Basin, which dominates the northern part of the subcontinent. The water dispute of Indus Basin Rivers between India and Pakistan, the dispute over Mahakali and Kosi between India and Nepal, and the dispute of India and Bangladesh over the use of Ganges and Teesta River are the causes of strained relations between the concerned countries. This research paper tries to understand the geographical, political, and legal context of how unresolved river water disputes in South Asia are causing problems. This study focuses on disputes over sharing of interstate river water among South Asian countries. While several political and legal ways and means have been attempted by these neighboring countries to address their disputes, it is observed that the treaties and agreements have not been effective in this matter. It becomes important to explore what kinds of mechanisms have been successful in resolving interstate river water disputes in other regions of the world, which may became a lesson for South Asia. The paper explores that collaboration on the local-international level will lead to trust-building and increased public pressure. The successful transboundary water cooperation requires both bottom-up and top-down engagements. The paper aims to contribute by providing an example of how investment in local-international cooperation can be used to improve transboundary water management. The GWN program has been selected for this case as it is a program that focuses directly on the cooperation between local communities.