Hydrochemical and microbiological quality of groundwater in the Merdja area, Tébessa, North-East of Algeria

Abstract

The aim of this study was to perform a preliminary assessment of the hydrochemical and microbial groundwater quality of the Merdja plain (Tébessa area). Twenty samples of groundwater collected from Bekkaria (Site 1) to Ain Chabro (Site 2) were assessed for their suitability for human consumption. Groundwater from the aquifer in the Merdja area can be divided into two major groups according to geographical locations and chemical compositions. Water in the center part of the study area is characterized by the dominance of chloride, sulfate, sodium, and potassium; whereas waters in the limestone aquifers in the west are dominated by the same cations but have higher concentrations of bicarbonate. Microbiological parameters were determined in 13 groundwater samples collected from the study area. Total coliforms, thermotolerant coliforms, E. coli, Enterococcus spp., Salmonella sp., Staphylococcus spp., and P. aeruginosa were detected in 96.36, 88.18, 100, 47.5, 97.27, 96.7, and 75 % of the groundwater samples, respectively. The pollution of groundwater comes from a variety of sources, Ouadi El Kebir River, including land application of agricultural chemicals and organic wastes, infiltration of irrigation water, septic tanks, and infiltration of effluent from sewage treatment plants, pits, lagoons, and ponds used for storage.