Delineation of groundwater potential zones in Araniar River basin, Tamil Nadu, India: an integrated remote sensing and geographical information system approach

The paper presents the development of a groundwater potential index (GWPI) map of the Araniar River basin, India, through an overlay analysis of climatic, geologic, geomorphic, soil and land use/land cover features of the basin using Landsat5 Thematic Mapper (TM) data and ArcGIS9.2. A correlation analysis of the developed GWPI map was carried out with a yield map of the basin to standardize the weights assigned to each theme. A maximum correlation coefficient of 0.922 was obtained when rainfall, geology, soil, slope, geomorphology and land use/land cover maps were overlaid with standardized weights of 0.49, 0.20, 0.17, 0.05, 0.05 and 0.04, respectively. The GWPI map showed groundwater potential zones as excellent, very good, good, moderate and poor with yield values in the ranges 293-361, 210-292, 126-209, 43-125 and 15-42 lpm, respectively. The analysis of post- and pre-monsoon water table depths also showed pronounced groundwater-level fluctuations in the central and eastern part of the basin. The GWPI map when combined with the post- and pre-monsoon water table depth maps may also help in locating suitable sites for artificial recharge for effective and efficient groundwater resource exploration and management of the basin.