Hydrochemical assessment of groundwater quality in the Narmada River Basin (Central India)

Abstract

This study details the hydrochemical characterization and human health risk assessment of groundwater in the Narmada River Basin. The study was performed based on data collected from 305 groundwater sample stations in the Narmada River Basin. Hydrochemical evaluation illustrated that cationic ions in the upper and middle Narmada Basin were dominated by Ca2+; however, in the lower basin it was dominated by Na+ ions. Similarly, anionic ions were dominated by HCO3− throughout the basin. A Chadha plot drawn from the collected data inferred that most groundwater belonged to the recharge water category (Ca-Mg-HCO3 type). Base-exchange indices of the collected data confirmed the presence of Na+-SO42− type of groundwater. Meteoric genesis indices indicated deep meteoric percolation groundwater. Further, Gibbs plots categorized groundwater samples in the rock dominated section, while chloro-alkaline indices confirmed direct as well as reverse ion-exchange reactions governing groundwater quality. Water Quality Index values showed that groundwater ranged from excellent to very poor. Human health risk of the Narmada River confirmed the non-carcinogenic risk for Nitrate (NO3−) and Fluoride (F−) ions. However, several indices justified that groundwater was ideal for irrigation. However, groundwater treatment is recommended before direct consumption such as drinking. HIGHLIGHTS Both reverse and direct ion exchange reactions and rock weathering govern the groundwater quality.; Dominance of Na+-SO42− type and deep meteoric percolation types of groundwater.; The Water Quality Index (WQI) ranges from excellent to very poor categories.; A non-carcinogenic risk due to nitrate and fluoride contamination was confirmed.;

Keywords

• chadha plot
• groundwater quality
• human health risk
• water quality index