Transboundary rivers raise critical concerns for state security amidst contemporary ecological strain and regional geopolitics in South Asia. The challenge of ‘water security’ is underscored by the substantial reliance on transboundary rivers, compounded by the multifaceted impacts of climate change and the simmering geopolitical tensions among riparian nations, especially in the complex dynamics between India–China and India–Pakistan. This study endeavours to illuminate distinctive characteristics of the South Asian transboundary governance framework, wherein rivers are subjected to intensive damming aimed at (a) harnessing hydroelectric potential and (b) leveraging water resources as geopolitical bargaining chips, thereby exerting pressure; however, order is not specified, particularly. In this intricate milieu, international conventions often fail to reconcile internal contradictions inherent within the transboundary governance paradigm. Consequently, transboundary water resources have metamorphosed into an extension of geopolitical realities, embodying intricate interplay between hydrology, geopolitics and state security within the region, especially between China, India and Pakistan.