Groundwater quality mapping using geographic information system (GIS): A case study of Gulbarga City, Karnataka, India
Spatial variations in ground water quality in the corporation area of Gulbarga City located in the northern part of Karnataka State, India, have been studied using geographic information system (GIS) technique. GIS, a tool which is used for storing, analyzing and displaying spatial data is also used for investigating ground water quality information. For this study, water samples were collected from 76 of the bore wells and open wells representing the entire corporation area. The water samples were analyzed for physico-chemical parameters like TDS, TH, Cl<sup>-</sup> and NO<sub>3</sub><sup>-</sup>, using standard techniques in the laboratory and compared with the standards. The ground water quality information maps of the entire study area have been prepared using GIS spatial interpolation technique for all the above parameters. The results obtained in this study and the spatial database established in GIS will be helpful for monitoring and managing ground water pollution in the study area. Mapping was coded for potable zones, in the absence of better alternate source and non-potable zones in the study area, in terms of water quality.
Keywords: Groundwater pollution, drinking-water, physico-chemical parameters, spatial interpolation.