Assessment of groundwater quality by water quality indices for irrigation and drinking in South West Delhi, India

Groundwater quality should be continuously monitored for irrigation and drinking purpose so that risk from geochemical contaminants can be reduced by appropriate treatment method. Therefore, the focus of the present study was to determine the suitability of groundwater collected from South West Delhi, India, for irrigation and drinking purpose on the basis of various water quality indices. In order to assess the groundwater quality, 50 samples were collected from different sites of selected study area and parameters such as pH, EC (electrical conductivity), total dissolved solids (TDS), salinity, total hardness (TH), total alkalinity (HCO(3)(−)), calcium (Ca(+2)), magnesium (Mg(+2)), sodium (Na(+)), potassium (K(+)), chloride (Cl(−)), Fluoride (F(−)), sulfates (SO(4)(−2)) and Nitrates (NO(3)(−)) were determined. Based on the above parameters, sodium adsorption ratio (SAR), soluble sodium percentage (SSP), residual sodium carbonate (RSC), permeability index (PI), magnesium adsorption ratio (MAR), Kelley's ratio (KR) and Na% were calculated. Water quality index (WQI), which is an important and unique rating to represent the overall water quality in a single term that is useful to determine the suitability of water for human consumption, was also estimated. The present dataset demonstrated the application of water quality indices that would be helpful to policymakers for appropriate management, treatment and sustainable societal development at large.