Foto Eric^1,, Allahdin Oscar¹, Biteman Olga¹, Akpekabou Brandon¹, Poumaye Nicole¹

Drilling water consumed in the South-West of the Central African Republic is the main source of drinking water. However, the chemical and bacteriological quality of these resources remains unclear. This study allowed us to classify the boreholes in the region according to their chemical and bacteriological quality in order to assess the risks associated with their consumption. The results obtained showed that the boreholes have an acidic pH and are weakly mineralized. Three chemical facies have been identified from the piper diagram which are calcium and magnesium bicarbonate, chloride and calcium sulfate, finally magnesium and sodium and potassium chloride. The mineralization of these boreholes is influenced by the nature of the rocks, in particular the carbonates, granites, clays and shales present in the region and also the external inputs due to the leaching of the soil. The results of bacteriological analyzes show the presence of fecal contamination germs in certain boreholes. The study revealed three quality classes: first class for good quality drilling water, which meets WHO standards, second class for acceptable quality water and third class for poor quality water.

drilling water, mapping, water quality, chemical facies