Groundwater quality assessment for drinking purpose in Gurugram district of Haryana, India

Groundwater is an important source of drinking water and irrigation. However, due to increased anthropogenic activities, its quantity and quality are gradually deteriorating over time. The current paper focuses on the evaluation of groundwater quality and its variability for drinking purpose in Gurugram district of Haryana. Geographical Information System based groundwater quality index (GWQI) is a cost-effective tool for the assessment of groundwater quality and its variability. Nine water quality parameters, i.e., sodium, potassium, magnesium, calcium, chloride, sulfate, nitrate, fluoride, and total dissolved solvent have been considered for quality assessment of pre-monsoonal season. Two GIS-based groundwater quality index maps GWQI-9 (for all the above mentioned parameters) and GWQI-4 (for the critical parameters whose concentrations exceeded the permissible limit) were produced. Subsequently, correlation analysis and factor analysis were performed to determine the degree of correlation and to identify the principal factor of contamination among all nine water quality parameters, respectively. Interpolated maps, concentration maps, and rank maps were developed for each parameter. Furthermore, the rank map was used to assign weight to each parameter. Based on rank and weight, the final GIS-based GWQI-9 and GWQI-4 were developed. Higher GWQI values reflect higher water quality. Overall, the north-eastern parts of the district have high water quality, while the western and northwestern periphery of Gurugram has low water quality. Except northern and north western region, most of region of Gurugram have poor water quality in terms of GWQI-4. It is possible to conclude that GIS-based GWQI could become a comprehensive approach for assessing surface or groundwater quality.