Exploring Microbial Contamination in Water Sources in Limpopo Province and Gauteng Province

Pollution of aquatic ecosystems is rising due to anthropogenic activities, with developing countries facing severe water contamination due to inadequate wastewater treatment, and limited access to clean water. This study investigates water microbial contamination in the Nandoni Dam, Thate Vondo Dam, Albasini Dam, the Xikundu Weir (Limpopo province), and the Orlando Dam (Gauteng province) in South Africa. Water quality was determined using possible human activities, physical parameters, and pathogenic indicators (Total coliforms (TC) and Escherichia coli (E. coli). TC and E. coli were detected using the Quanti-Tray®, and E. coli was characterized using multiplex Polymerase Chain Reaction (mPCR). The Vitek-2 automated system was used for isolate identification. The Electrical conductivity (EC) at all sites met South African water quality guidelines of DWAF and WHO, while other physical parameters (TDS, pH, and temperature) varied across the sites. TC levels exceeded the recommended limits and 85% of samples tested positive for E. coli. Five pathogenic E. coli were identified: Enterohaemorrhagic E. coli (EHEC), Enteropathogenic E. coli (EPEC), Enteroaggregative E. coli (EAEC), Enteroinvasive E. coli (EIEC), and Enterotoxigenic E. coli. Nandoni Dam and Orlando Dam showed a high diversity of bacterial species. Overall, the microbial quality of the assessed water was substandard.