FLOOD HAZARD ZONATIONOF NOA MANGALDAI RIVER BASIN, ASSAM USING GIS AND REMOTE SENSING

Among all the geomorphic hazards the flood is the most frequently occurring hazards in riverine landscape. The Noa-Mangaldai River basin is a part of the Brahmaputra River basin, Assam. The basin has such a unique and diverse geo-physical as well as hydrological setup that the natural processes and factors alone can create frequent devastating floods especially in the middle and lower reach of the river. Considering the gravity of the flood hazard and flood plain management various governmental and non-governmental organizations and also the researchers have made some attempts towards floodplain zoning at different times.In the present paper, the flood hazard zonation map of Noa-Mangaldai river basin,has been prepared applying multi-criteria evaluation method using GIS and categorize the basin into four flood hazard zones Viz. Very high, high, moderate, low and flood free zone.Result shows that, more than 30% area of the basin has fall under very high to moderate floodprone category.