Hydrogeochemical characteristics and evaluation of groundwater quality in Varadaiahpalem, Andhra Pradesh, South India

This research investigates the hydrogeochemical characteristics of groundwater in the Vardaiahpalem region of Andhra Pradesh, South India, focusing on its suitability for irrigation and drinking purposes. A comprehensive hydrogeochemical analysis was performed on forty groundwater samples collected from local wells, assessing key physicochemical parameters including pH, electrical conductivity (EC), total dissolved solids (TDS), and concentrations of major ions (Na+, K+, Ca2+, Mg2+, F−, Cl−, HCO3−, and SO42−). Specific indices such as the permeability index, magnesium ratio, Kelly ratio, sodium adsorption ratio (SAR), adjusted sodium adsorption ratio (Adj.SAR), and water quality index (WQI) were utilized to evaluate water quality for irrigation. Groundwater SAR levels indicate a low sodium hazard, suggesting a reduced risk of soil degradation for irrigation. Eighty percent of groundwater is classified as Class I by the Doneen Permeability Index, making it suitable for irrigation. The USSL and Wilcox diagrams further validated the irrigation potential of the groundwater. The study employed a multidisciplinary approach, utilizing statistical analysis and graphical methodologies, including Chadha and Gibbs diagrams, to elucidate the chemical control mechanisms of groundwater. Groundwater Samples are categorized as Ca–Mg–Cl, Na-HCO3, and Ca-Mg-HCO3 due to saline or seawater intrusion that increases chloride levels. It mainly focuses on bicarbonate (HCO3−) as the key anion and sodium (Na+) as the main cation. The WQI method assessed the potability of the water, while binary diagrams facilitated an understanding of the chemical evolution mechanisms. This study calls for collaboration with local stakeholders and policymakers to translate these findings into actionable practices, promoting sustainable agriculture and preserving water quality.