Study of the Microbiological Quality of Groundwater Consumed by the Population of the Messassi District in the City of Yaoundé, Cameroon

Abstract

The lack of an efficient drinking water management and distribution system across the territory of developing countries has forced populations to turn to other sources of water supply including wells and boreholes. The objectives of this study were to assess the microbiological quality of groundwater consumed by the population of the Messassi district in the city of Yaoundé. After a household survey to identify sources of drinking water supply, water samples were taken from the boreholes and wells most frequented by the population. The microorganisms were isolated after filtration of 100 ml of sample through a nitrocellulose membrane, with a microporosity of 0.22 µm. This membrane was then placed on the surface of the agar plates and incubated at 37°C and 44°C for 24 +/- 2 hours. After subculture on different media, pure bacterial isolates were identified by their cultural characteristics and commercialized biochemical galleries. Of the 101 households surveyed, 23 were supplied with borehole water and 21 with water from developed wells, i.e. 43.56% of households that consumed and used groundwater for their various needs when the other 56.44% households consumed tap water supplied by Cameroonian Water or mineral water. Of the 20 water samples that were taken in total, 04 came from boreholes, 07 from developed and regularly disinfected wells and 09 from developed and not regularly disinfected wells. The probable source of pollution was that of latrines located less than 15m from the wells (70℅). The 04 water samples taken from the boreholes were all compliant with total flora (TF), total coliforms (TC) and fecal coliforms (FC). Of the 07 wells developed and disinfected regularly, 06 samples were non-compliant with TF while 05 were non-compliant with TC and FC. Concerning the samples from the 09 wells developed and not disinfected, they were non-compliant with both TF and TC and FC. Bacterial species such as <i>Salmonella arizonae </i>(40℅), <i>E. Coli</i> (30℅), <i>Proteus </i><i>mirabilis</i> (20℅) and <i>Salmonella choleraesuis </i>(10℅) were isolated. The results of the current survey show risks of microbiological contamination among the drinking water samples studied and consumed by the population. Regular and proper disinfection of the boreholes and wells in the town of Messassi is necessary to ensure a better quality of life for the population that consumes groundwater.