GIS-Based Spatial Distribution of Groundwater Quality and Regional Suitability Evaluation for Drinking Water

Hydrochemistry mapping of groundwater is one of the important aspects of water resources management of an area based on usages such as drinking water or irrigation, and their quality requirement. Such mapping could lead to optimal utilization and protection from quality deterioration. In this paper, a geospatial based water quality index is developed for preparing water quality class suitability map. The aim of this study is to provide an overview of the spatial variation of groundwater quality parameters, i. e., Fluoride (F-), Nitrate (NO3-), Chloride (Cl-), Total Dissolved Solids (TDS), pH and Total Hardness (TH) in the Khushkhera -Bhiwadi-Neemrana Investment Region (KBNIR). Groundwater samples were collected from 14 locations, tested in the laboratory and were analyzed using Geographical Information Systems (GIS) techniques. Geospatial analyst tools were used to generate various thematic maps, and interpolation techniques were applied to identify the spatial distribution of groundwater quality parameters. Groundwater quality was analyzed in detail and compared with BIS and WHO water quality standards. Multivariate statistical techniques, such as Correlation Matrix Analysis and Principal Component Analysis (PCA) were carried out. The correlation coefficient showed TDS highly correlated with chloride (r = 0.725), and a negative correlation (r =-0.656) between pH and nitrate. It was observed that 36.02% of the populated area depends on excellent quality groundwater and 23.56% on good quality groundwater, while poor and moderately poor quality groundwater is available for respectively 6.26% and 34.16% of the populated area. Also, only 65.88% of the total geographical area within the KBNIR region is hydrochemically suitable for drinking purposes. Attempts are also made to compare these results with PCA results.