Assessment of Physico-chemical Suitability of Groundwater for Drinking and Agriculture Purposes in Bonoua and Samo (South-East Côte d’Ivoire)

Abstract

Aims: The goal of this study is to know the quality of groundwater from Bonoua and Samo, for drinking and irrigation purposes. Methodology: Three (3) samples from boreholes and hand dug wells were taking for this study. Then groundwater quality and its suitability for irrigation and domestic purposes in Bonoua and Samo, South-East Côte d’Ivoire was examined using various physico-chemical parameters such as pH, electrical conductivity, total dissolved solids, total hardness, calcium, magnesium, sodium, potassium, bicarbonate, sulfate, chloride and heavy metals. These parameters were used to assess the suitability of groundwater for domestic purposes by comparing with the WHO standards. Sodium adsorption ratio (SAR) and percentage of sodium (%Na) were used for irrigation suitability assessment. Results: The groundwater is acidic with a pH that varies from 4.8 to 5.4. The electrical conductivity values is low with an average of 66.54±29.07 μS/cm. The sample analysis reveals that except to the pH, the groundwater is entirely fit for drinking with respect to WHO guidelines. The groundwater from Bonoua and Samo is a fresh water and classified into three principal hydrochemical facies depending on the dominant ions present: HCO3-Ca-Mg; Cl-SO4-Ca-Mg and Cl-HCO3-Mg-Ca. The PCA results showed that two phenomenon controlled the process of groundwater mineralization in the area. In fact weathering and dissolution of minerals were found to be the major geochemical processes governing the groundwater evolution. Groundwater is also influenced by anthropogenic activities such as agricultural practices (Fertilizers spreader). Conclusion: Groundwater from the study area is influenced by anthropogenic activities such as agricultural practices. Based on SAR and %Na almost samples are suitable for irrigation purposes.