TheJamuna River (Bengali:যমুনা,romanized: yamunāJomuna) is one of the three main rivers ofBangladesh. The two other major rivers in Bangladesh are thePadma and theMeghna. The Jamuna is the lower stream of theBrahmaputra River, which originates inTibet asYarlung Tsangpo, before flowing through India and then southwest into Bangladesh. The Jamuna flows south and joins thePadma River, nearGoalundo Ghat, before meeting theMeghna River nearChandpur. The Meghna then flows into theBay of Bengal.
The Brahmaputra-Jamuna is a classic example of abraided river and is highly susceptible tochannel migration andavulsion.[1]It is characterised by a network of interlacing channels with numeroussandbars enclosed between them. The sandbars, known inBengali aschars, do not occupy a permanent position. The river deposits them in one year, very often to be destroyed later, and redeposits them in the nextrainy season. The process of bank and deposit erosion together with redeposition has been going on continuously,[2] making it difficult to precisely demarcate the boundary between the districts ofSirajganj andPabna on one side and the districts ofMymensingh,Tangail andDhaka on the other. The breaking of achar or the emergence of a new one is also a cause of much violence and litigation. The confluence of the Jamuna and the Padma rivers is unusually unstable and has been shown to have migrated southeast by over fourteen kilometres between 1972 and 2014.[3]
In Bangladesh, the Brahmaputra is joined by theTeesta River (orTista), which is one of its largest tributaries.
James Rennell made a survey between 1764 and 1777 and his maps are one of the earliest authentic maps of Bengal in existence. In these maps, Teesta is shown as flowing through North Bengal in several branches — Punarbhaba, Atrai, Karatoya, etc. All these streams combined lower down with theMahananda river, now the westernmost river in North Bengal, and taking the name ofHoorsagar finally discharged into the Ganges at Jafarganj, near modern Goalundo. The Hoorsagar river is still in existence, being the combined outfall of theBaral, a spill channel of the Ganges, the Atrai, the Jamuna or Jamuneswari (not the main Jamuna through which the Brahmaputra now flows), and the Karatoya, but instead of falling into the Ganges, it falls into the mainJamuna, a few kilometres above its confluence with the Padma at Goalundo.[4]
Below the Teesta, the Brahmaputra splits into twodistributary branches. The western branch, which contains the majority of the river's flow, continues due south as the Jamuna to merge with the lower Ganges, called thePadma River. The eastern branch, formerly the larger but now much smaller, is called the lower orOld Brahmaputra. It curves southeast to join theMeghna River near Dhaka. The Padma and Meghna converge nearChandpur and flow out into the Bay of Bengal. This final part of the river is calledMeghna.
In the past the course of the lower Brahmaputra was different and passed through theJamalpur andMymensingh districts. The river flowed east ofDhaka and the old course is now calledOld Brahmaputra River.[5][6] The hugeearthquake on 2 April 1762 of estimated magnitude 8 on the moment magnitude scale caused tectonic uplift of theMadhupur tract.[7] The main channel of the Brahmaputra at Bhahadurabad point was switched southwards and opened as Jamuna due to the result of caused tectonic uplift of the Madhupur tract. The earthquake caused both uplift and subsidence that resulted in change in course of theBrahmaputra River to from east of Dhaka (Old Brahmaputra River) to 150 kilometres (93 mi) to the west via theJamuna River. The old course can be seen onhttps://ars.els-cdn.com/content/image/1-s2.0-S0169555X21001045-ga1_lrg.jpg.
The Jamuna is a very wide river. During the rainy season it stretches about 8–13 km (5–8 mi) from bank to bank. Even during the dry season when the waters subside, the breadth is seldom less than 3–5 km (2–3 mi).
The Jamuna was a barrier in establishing a direct road link between the capital Dhaka and northern part of Bangladesh, better known as Rajshahi Division, until 1996. This was mitigated by the completion of theJamuna Multi-purpose Bridge.[8] The Jamuna is also a very importantwaterway. It is navigable all year round by large cargo and passenger steamers. Before thePartition of Bengal in 1947, passenger steamers used to ply up to Dibrugarh in the state of Assam in theIndian Union. At present two steamer ferry services link the district of Pabna with the districts of Mymensingh, Tangail and Dhaka. TheBangladesh Railway maintains a ferry service between Sirajganj and Jagannathganj in Mymensingh. The other ferry service between Nagarbari in Pabna and Aricha in Dhaka is run by the C & B Department.
