A trans-boundary river is a river that crosses at least one political border, either a border within a nation or an international boundary. The country of Bangladesh has the greatest number of these rivers, almost all of which cross national boundaries.
Trans-boundary rivers of Bangladesh
Bangladesh has at least 58 major rivers that enter that nation from India or Myanmar. The hydrologic and political effects of rivers that cross significant boundaries are enormous. Rivers have positive effects in that they carry a significant amount of sediment which aids in building land in estuarine regions. However this sediment raises the height of riverbeds thereby causing flooding. International conventions governing water sharing lead to complex political disputes.
India and Bangladesh share 54 common rivers of which agreement has been reached only on sharing of waters of the river Ganges. The India-Bangladesh Treaty on the Sharing of the Ganges Waters was signed on December 12, 1996 and is based on a sharing formula of the flows measured at Farakka,during the lean season each year, from 1 January to 31 May. The 30-year Treaty is renewable by mutual consent.