FLOODS IN ASSAM
Flood in Assam is characterized by their extremely large magnitude, high frequency and extensive devastation. This natural hazard repeats itself year and not only costs lives but also leaves the economy of the state, which is largely agricultural, in utter shambles. Flood is not a new phenomenon in Assam. There have been references to disastrous floods in past, caused by the Brahmaputra river, including the ones when nearly half of Dibrugarh town was washed away by the flood in 1954.
In Assam floods are caused by two river systems – the mighty Brahmaputra in the north and Barak in the south. The geographical setting of the region, high intensity rainfall, easily erodible geographical formations, earthquake Zone, massive deforestation, great amount of land used, and explosive population growth in the flood control are some of the dominant factors that cause floods in Assam.
The Brahmaputra valley is surrounded by hills and plateaus and therefore environmentally sensitive to floods.
The prevailing weather patterns have a strong bearing on the occurrence and intensity of floods in Assam. Monsoons rains from June to Septembers feed the Brahmaputra and the Barak along with their tributaries with excessive water. The cyclonic Depressions in the Bay of Bengal too are responsible for devastating floods like the October 1986 on that created havoc in the Nagoan district.
The earthquake of 1950 caused extensive landslides, changes in land in the Brahmaputra valley and also changes in the normal course of the rivers. A significant feature of the flooding rivers in Assam is the excessive loads of sediment carried by them and this was triggered by the earth quake of 1950. At places like Dibrugarh the river bed was raised by several metres.
Besides the natural calamities, harmful human activities like deforestation, accelerated rated of land use, filling up low lying areas of for the construction of buildings and reckless urban developments are also responsible for floods in Assam. High rate of population growth in the form of high birth rate and immigration from border countries has led to unscientific encroachment.
Floods in Assam cause huge destruction and irreparable loss to the state's economy which is largely agrarian. It cause great damage to grazing lands and fodder crops, affect grains as well as seeds stored in granaries and destroy cattle. It also takes away the nutrient rich top soil, even after the flood waters recede it leaves behind a many Problem for the health as well as civic authorities. Malaria, Cholera and other disease appear causing a heavy loss of life. Most of the damage is caused in the rural areas leaving the people poorer and starving.
Therefore there is an urgency for controlling the fury of floods and reducing their impact. Unless some thing is done agriculture, energy, industry, transport and communication in fact the whole economy of Assam will continue to suffer permanent large scale embankments, erection of multipurpose reservoirs, and adoption of sound watershed management along with massing a forestation, soil conservation and land use regulation would go a long way in controlling floods in Assam.