Evaluating groundwater prospects using GIS techniques

Evaluating groundwater prospects is important for development and resource management of a region. In this work various features such as geomorphology, lithology, lineament, topography, soil type, and drainage pattern of a part of lower Mahanadi Basin was studied in order to delineate areas that are expected to be suitable for future groundwater exploration in the study region. The area is composed of geological features that vary from hard rock terrain in north-western part to deltaic plain and coastal region in the south-eastern part. An integrated analysis of various parameters provides better estimate of subsurface characteristics from groundwater perspective. On the basis of different weights assigned to geological factors, surface runoff, infiltration, and other factors, it was found that about 42% of the total area has good prospects of groundwater, whereas approximately 21% of the area has relatively feeble prospects. Borewell discharge data collected by the Central Groundwater Board (CGWB) confirm results obtained by GIS analysis. Results are useful for detailed investigations of the region through various geophysical techniques, pinpointing exploratory borewell locations and groundwater resource management for the region.