Bangladesh is a riverine country. According to Bangladesh Water development board (BWDB)[1] about 907 rivers currently flow in Bangladesh (during summer and winter), although the numbers stated in some sources are ambiguous.[2][3][4] As stated by a publication called বাংলাদেশের নদ-নদী by BWDB (Bangladesh Water development board), 310 rivers flow in the summer although they republished another study in 6 volumes where stated 405 rivers.[5] The number differs widely due to lack of research on the counts and the fact that these rivers change flow in time and season. Historical sources state about 700 to 800[6] rivers but most of them have dried up or are extinct due to pollution and lack of attention. The numbers also differ because the same rivers may change names in different regions and through history. About 17 rivers are on the verge of extinction.
A total of 57 international rivers flow through Bangladesh, 54 from India and 3 from Myanmar. The number of international rivers can be 58 as Brahmaputra is called "Nod" while the general term for river is "Nodi". The gender division of rivers is interesting from history and mainly depending on the source of the river but not the size or flow briskness. Sangu and Halda are the only two internal rivers originated and finished within Bangladesh. Of the three major rivers, the Jamuna - part of the Brahmaputra - is the longest, Padma is the swiftest, and Meghna is the widest. According to banglapedia, 700 rivers flow in Bangladesh,[7] but the information is old and obsolete. There is an including tributaries flow through the country constituting a waterway of total length around 24,140 kilometres (15,000 mi).[8] But the number differs ambiguously due to the lack of updated information. Most of the country's land is formed through silt brought by the rivers. Bangladesh geography and culture is influenced by the riverine delta system. Bangladesh lies in the biggest river delta of the world - the Ganges Delta system.