Assessment of Groundwater quality for drinking and irrigation purposes in Rohtak district, Northern India

Abstract

Abstract This study discusses about the suitability of groundwater for drinking and irrigation use in Rohtak district of Haryana state, India. Ninety-four groundwater samples were collected during Pre monsoon and Post monsoon periods and analyzed by several methods, including Entropy water quality index (EWQI), Sodium Absorption Ratio (SAR), Permeability Index (PI), Sodium Percentage (Na %), Kelly Ratio (KR), Magnesium Adsorption Ratio (MAR), US salinity diagram, and Gibbs diagram. The spatial distribution maps of EWQI and irrigation indices were also plotted using the IDW technique in ArcGIS. The result suggests that the groundwater quality in the central part extending towards the south-western part of the area can be categorized as poor. The major ion concentrations were reported in the following order: Mg2+ > Ca2+ > Na+ > K+, and Cl- > SO42- > NO3- > HCO3- > F- > CO32- respectively. Moreover, results revealed that most of groundwater samples exceeded the desirable limits for drinking water as suggested by World Health Organization. The EWQI assessment indicates that 23.4% and 38.4% of groundwater samples have extremely poor quality in Pre monsoon and Post monsoon, respectively. Analysis of water quality for irrigation shows that various indices like EC, SAR, PI, Na %, KR, and MAR exceed their standard limit, and mostly samples are unsuitable for irrigation. The Gibbs diagram and other bivariate plots demonstrate that various ions in groundwater can be attributed to silicate and carbonate weathering, which occur through water-rock interactions and ion exchange phenomena. Additionally, the US Salinity diagram verifies that most groundwater samples exhibit significant salinity hazards, particularly concerning high sodium levels. The results of this study are highly valuable for efficiently allocating and managing the resources within this particular district.