12.4.2. Case Study- Brahmaputra River Bank Erosion, Assam
For studying the erosion problem in Marigaon district post flood satellite data sets of 1987-91 and 1990-1998 were
selected since high floods have occurred during 1988 and 1998. All the satellite data were geometrically rectified
to the master map base for positional accuracy. Image enhancement techniques were applied on all the individual
satellite data scenes to obtain better contrast among the features especially between land and water. The river
configuration along with bank lines was delineated consisting of active river channel,
sand and island. The bank lines were intersected to identify and estimate the amount of erosion and deposition at
different pockets along the main Brahmaputra in Marigaon district in GIS environment. Figure