Groundwater quality from a part of Prakasam District, Andhra Pradesh, India

Abstract

Quality of groundwater is assessed from a part of Prakasam district, Andhra Pradesh, India. Groundwater samples collected from thirty locations from the study area were analysed for pH, electrical conductivity (EC), total dissolved solids (TDS), calcium (Ca²⁺), magnesium (Mg²⁺), sodium (Na⁺), potassium (K⁺), bicarbonate (HCO3-), chloride (Cl⁻), sulphate (SO42-), nitrate (NO3-) and fluoride (F⁻). The results of the chemical analysis indicate that the groundwater is alkaline in nature and are mainly characterized by Na⁺–HCO3- and Na⁺–Cl⁻ facies. Groundwater chemistry reflects the dominance of rock weathering and is subsequently modified by human activities, which are supported by genetic geochemical evolution and hydrogeochemical relations. Further, the chemical parameters (pH, TDS, Ca²⁺, Mg²⁺, Na⁺, HCO3-, Cl⁻, SO42-, NO3- and F⁻) were compared with the drinking water quality standards. The sodium adsorption ratio, percent sodium, permeability index, residual sodium carbonate, magnesium ratio and Kelly’s ratio were computed and USSL, Wilcox and Doneen’s diagrams were also used for evaluation of groundwater quality for irrigation. For industrial purpose, the pH, TDS, HCO3-, Cl⁻ and SO42- were used to assess the impact of incrustation and corrosion activities on metal surfaces. As a whole, it is observed that the groundwater quality is not suitable for drinking, irrigation and industrial purposes due to one or more chemical parameters exceeding their standard limits. Therefore, groundwater management measures were suggested to improve the water quality.