River Flow Changes

Being the lower riparian country, Bangladesh is largely dependent on freshwater availability from the trans-boundary rivers entering the country. Recent research on global freshwater storage depicts the area in-and-around Bangladesh to be water deficit areas. It is characterized as an area with water depletion and percolation decrease. The average annual flow generated from the GBM basins are 1,192,469 Mm3 among which 361,593 Mm3 (30 percent) comes from the Ganges basin, 660,777 Mm3 (55 percent)from the Brahmaputra basin and 170,100 Mm3 (14 percent) from the Meghna basin.

Annual flow of Ganges, Brahmaputra and Meghna Basins will increase by 17-28 percent, 2-5 percent and 1-4 percent for SSP5-8.5 scenario in 2050s respectively (CEGIS analysis).

The figure presents the seasonal distribution of flow in 2050s. Flow will increase highly (18-30 percent) in Ganges basin while smaller percent of increase is seen in Brahmaputra and Meghna. Winter flow will decrease in Brahmaputra and Meghna basin in SSP 5-8.5.

River flow changes