India’s suspension of the Indus Waters Treaty (IWT) in May 2025, following the baseless Pahalgam terror attack, has opened a dangerous new chapter in South Asia’s already fragile security landscape. The treaty, signed in 1960 with World Bank mediation, was long considered a rare success story of transboundary cooperation. It underwent wars, crises, and decades of hostility between India and Pakistan. Its abrupt suspension now threatens not only bilateral water resources management but also regional stability, raising the possibility of water being used as a weapon in one of the world’s most volatile regions.

The Indus Basin itself emphasizes the gravity of this decision. Originating in the glaciers of the Himalayas, Karakoram, and Hindu Kush, the basin covers about 1.1 million square kilometers and sustains approximately 300 million people across India and Pakistan. The Indus River inclines from elevations above 4,500 meters in Tibet and Kashmir to less than 10 meters at its delta in Sindh, creating steep gradients in its upper reaches and a flatter slope averaging 1:7,000 across the Sindh floodplains. This topographic transition explains both the massive hydropower potential upstream and the vulnerability of downstream floodplains. The Indus floodplain, stretching across Punjab and Sindh, is fertile but fragile; its flat terrain makes it highly dependent on controlled irrigation flows, and any disruption upstream converts rapidly into shortages downstream.

Average annual flows of the Indus River system are estimated at 207 billion cubic meters, yet variability is high. Monsoon rainfall contributes about 80% of annual discharge, while glacial melt provides critical base flow during dry months. Pakistan, as the downstream riparian, depends on this system for 93% of its total water use, irrigating 16 million hectares of farmland. With live storage capacity in its major reservoirs, Tarbela and Mangla, limited to just 14.4 million acre‑feet, hardly 10% of annual flows, any disruption in upstream releases can trigger immediate shortages. This........

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