Abstract

The present study examined the hydrochemical facies of groundwater present in the Coastal Sedimentary basin of Togo around drinking water supply. The study aim at explaining the controlling processes responsible for various facies. The parameters including pH, electrical conductivity (EC), K, Na, Ca, Mg, Cl, HCO₃, SiO₂, SO4 and NO₃ in water samples were analyzed and based on standard procedures. The data obtained were subjected to R-mode factor analysis. Two factors were extracted. Factor 1 include EC, Na, Cl, Ca, SO₄ and K and explained 59.88% of the total variance, Cl and EC and reflected the signature of saline water incursion. Factor 2 has high loading values of pH,HCO₃, SiO₂ and NO₃ which explained 34.76% of the total variance. pH and HCO₃ are the processes of natural rainwater recharge and water-soil/rock interaction process which eventually as acid-rain recharges aquifers in the vicinity. The presence of nitrate in groundwater reflects the anthropogenic impact of domestic sewage, industrial waste, uncontrolled landfill waste, fertilizers, and manure on the study area. This paper demonstrates the effectiveness of factor analysis in evaluating hydrochemical processes in coastal and industrial areas.

Key words: Coastal aquifers, factor analysis, water supply, nitrate, hydrochemical modeling.