A LEADING Indian think-tank has reportedly warned that diplomatic relations among Bangladesh, China, India and Nepal are likely to be 'strained' due to depletion in water flows of trans-boundary rivers for both human intervention and natural factors and resultant increase in displacement and migration of people across the region. In a report titled 'The Himalayan Challenge', a Mumbai-based think-tank Strategic Foresight Group expressed its 'concern' over India's river-linking project and China's plan to build a dam on River Yarlung Tsangpo as these projects would substantially reduce water flows and cause devastation at the down stream. 

The relations between India and Bangladesh may be strained due to a decrease in flow of rivers for the river-linking project. According to the report, though this deterioration of relations is unlikely to cause military confrontation, it can lead to new external alliances, producing fresh alignments and polarisations. Water scarcity, shortage of rainfall and their cumulative effects will lead to both displacement and migration of 50 to 70 million people in these countries by next 40 years. The Ganges in India, and Bangladesh, and its distributaries, are likely to lose between 15 and 30 per cent water by the second half of the century as the Himalayan glaciers will be seriously affected by global warming. 

The Brahmaputra in Bangladesh and India will also lose about 7 per cent to 14 per cent of the annual flow due to depletion of glaciers. While glacial melting will eventually reduce river flow, an increase in temperature in some areas will cause heavy concentrated precipitation increasing the risk of flooding. The demand for water will increase due to growth of population and economic development. It might not be possible to use the available water resources because of pollution and losses caused by inefficient water management.