Groundwater Prospect Evaluation in the Interfluves of the Rivers Brahmaputra and Kolong, Assam Using Remote Sensing and GIS Techniques

Abstract

Groundwater prospect evaluation in the interfluves of the Rivers Brahmaputra and Kolong, Assam has been studied by considering the geomorphology, lithology, drainage pattern and drainage density, slope and land use/land cover (LU/LC) of the area. The major geomorphic, lithologic and land use/land cover units of the area have been identified and delineated from satellite imageries. Slope map and drainage map of the study area were generated from the SOI toposheets as well as from the satellite imageries. The drainage density map was generated from drainage network of the interfluves using GIS. To demarcate the different groundwater prospect zones of the study area, all the thematic layers are integrated by raster index overlay technique in GIS. Weights are assigned to different thematic layers and ranks are assigned to different categories/classes of the thematic layers for the overlay analysis in GIS. The resultant map was classified into groundwater prospect zones as very good, good, moderate and poor. The groundwater prospect zone map indicates that the most part of the area is having well to very good groundwater prospect zones.