Analysis of the Microbiological Quality of Drinking Water from Wells and Boreholes in the City of Mongo (Chad)

Abstract

Water is an essential mineral compound that plays an important role in life, health, and human dignity. Due to the absence of the Chadian Water Society (STE) networks in certain neighborhoods, households are forced to source water from other places, such as wells and boreholes.  Objective of this study is to assess the microbiological quality of well and borehole water consumed in the city of Mongo. To carry out this study, a randomized selection of forty-three (43) water points, including sixteen (16) wells and twenty-seven (27) boreholes, was made, and samples were collected. These samples were transported to the National Water Laboratory (LNE) for the analysis of several microbiological parameters, namely Escherichia coli, Total coliforms, Fecal coliforms, Fecal enterococci, Salmonella spp, and Total aerobic flora. The technique used for this analysis is spread plating and membrane filtration. The average values obtained for borehole water are 0.187x10⁴ CFU/100 ml for Total coliforms, 0.646 x10³ CFU/100 ml for Fecal coliforms, 1.77 x10³ CFU/100 ml for Escherichia coli, 50 CFU/100 ml for Fecal enterococci, 11.11 CFU/100 ml for Salmonella spp, and 1.1888 x10⁴ CFU/100 ml for Total aerobic flora. Regarding well water, the average values obtained are 2.081 x 10³ CFU/100 ml for Total coliforms, 0.412 x 10³ CFU/100 ml for Fecal coliforms, 0.7 x 10³ CFU/100 ml for Escherichia coli, 169 CFU/100 ml for Fecal enterococci, 1.4983 x 10⁴ CFU/100 ml for Salmonella spp, and 6.25 CFU/100 ml for Total aerobic flora.  Microbiological analyses showed a high bacterial density in most samples, making them unfit for human consumption when compared to the WHO drinking water standards. Therefore, appropriate intervention strategies must be implemented to address these issues.