Hydrogeochemical characterization of ground and surface water in the Eastern part of the Adamawa-Yade Domain, Bertoua-Cameroon

Abstract

Groundwater and surface water are major sources of water supply to the inhabitants of Bertoua. Hydrogeochemical study was conducted in the study area aimed at identifying the processes that control the chemistry of groundwater sources and to examine the quality of the water sources fordomestic and agricultural purposes. Fifty water samples were collected from boreholes, open wells, springs, and rivers within the study area in January 2022 (the dry season). The samples were analyzed for physicochemical characteristics including pH, electrical conductivity (EC), total dissolved solids(TDS) and major ions. The water samples were acidic with 94% of pH values less than 6.5. The EC varied from 21-776 µS/cm and TDS (8.5-388 mg/l).The low EC and TDS indicate low mineralization and fresh water. The relative abundance of major ions (meg/l) was Ca2+> Mg2+> K+>Na+ for cations and HCO3- >CL->NO3>SO4-for anions. These major ions concentrations were low and within the WHO guideline values for drinking water. From Piper diagram two dominant water facies were observed; Ca-Cl and CaHCO3 with some samples plotting in mixed CaMgCl. Rock-water interaction, ion exchange, silicate weathering and anthropogenic activities were the processes responsible for the groundwater chemistry with some minor evaporative effects. These major ions concentrations were low and within the WHO guideline values for drinking water.Based on Sodium Adsorption Ratio and Residual Sodium Bicarbonate all samples fall in the excellent category for agriculture.