Northern Ganges tributaries such as Kosi , Gandak and Mahananda are the most flood - prone , but southern tributaries also contribute .
Bangladesh -- at the confluence of Brahmaputra River and Ganges River -- suffers from severe floods almost every year .
Northern Ganges River tributaries such as Kosi , Gandak and Mahananda are the most flood - prone , but southern tributaries also contribute .
Bangladesh -- at the confluence of Brahmaputra River and Ganges River -- suffers from severe floods almost every year .