EVALUATION OF SINUOSITY INDEX OF DHAN SIRI (SOUTH) RIVER CHANNEL AND BANK EROSION, ASSAM IN GIS

Abstract: The Dhansiri River is a highly meandering river. Its Sinuosity Index has been evaluated using satellite imageries of 1999 and 2008 which varies from 1.22 to 4.91. The river acquires a meandering course as it flows through the alluvial plains of Assam and is responsible for frequent course change and shifting of banklines due to consistent bank erosion. The progressive gradual change of the meander bends has been observed by superimposing the river layers of 1999 and 2008 in GIS platform. The length of the river course in 2008 (307.74km) became shorter by 6.20 km than that in 1999(313.94km). In the present study it has been found that the total area lost as a result of erosion is 13.13834 sq km and the total area gained as a result of sediment deposition along its bank is 15.15894 sq km.

Keywords: Dhansiri River, Sinuosity Index, GIS, Landuse, Landcover, Erosion.