[1] Since the beginning of twentieth century, the channel of the main Haora River has been modifying over time.
Firstly, by the then king Maharaja Birendra Kishore Manikya, and after that by the Government agencies and local people.
To meet the increasing demand of water of the city, Government as well as the local people have been constructing several obstructions: Other human activities like, land-use change, sand mining, water collection, solid waste disposal, agriculture, and cutting of tilla land for supplying raw materials to the brick industries have also caused the change of the river course, modifying the natural dynamics of the river.
(Tillas are the low elevated denudational uplands which are bifurcated by narrow dry up channels, called lunga.
[3] All the rivers draining the State originate in the hill ranges and are prone to flood during the rainy season.