Transboundary Rivers and Water-Sharing Treaties

More than 250 river and lake basins worldwide cross international borders, according to figures compiled by the Transboundary Freshwater Dispute Database at Oregon State University, and the resulting need for upstream and downstream states to coordinate has produced some of the most durable, and some of the most contested, international agreements over natural resources. The Indus Waters Treaty of 1960, negotiated over nine years with World Bank mediation and signed by India's Prime Minister Jawaharlal Nehru and Pakistan's President Ayub Khan, allocated the three western rivers of the Indus system — the Indus, Jhelum, and Chenab — primarily to Pakistan, and the three eastern rivers — the Ravi, Beas, and Sutlej — to India. The treaty proved remarkably resilient, surviving the India-Pakistan wars of 1965 and 1971 and the 1999 Kargil conflict, though it came under severe strain when India announced it was holding the treaty in abeyance in 2025 following a deadly militant attack in Pahalgam, illustrating how even long-standing water treaties remain hostage to broader bilateral political relations.