Water demand and ecosystem nexus in the transboundary river basin: a zero-sum game

Abstract

The water demand in the upstream and downstream of a transboundary river basin varies based on the water use by the irrigation projects, dam, hydroelectricity, ecosystem, livelihood practices and household activities of the people. The study considered the case of Teesta river basin and estimates the water demand of upstream, downstream region as well as entire Teesta river basin shared by India and Bangladesh. The water productivity method exercised in the study demonstrates that 2648 and 1971 cumec water is required to fulfill the irrigation demand of command and irrigable areas, respectively, of entire Teesta basin throughout the year against 198, 1472, 793 cumec water discharge in dry, monsoon and lean season. Although there is a substantial water demand for the hydropower projects in the upstream, it is appeared that water required only by the upstream irrigation project is beyond the water supply capacity of the Trans-Himalayan river Teesta during dry and lean season. This may underpin the shortage of water in the lower riparian country, which fuels the zero-sum game in the river basin, where one player is affected by the intervention of the another player. The result from this analysis with zero-sum game perspective may be useful for reviewing transboundary water policies, basin management and development, sustainable water resource management and water sharing mechanism among countries in the transboundary river basin.