Bacteriological And Physicochemical Characterisation Of Aora Loko Stream Water, Kenya

Abstract

Safety and quality of drinking water is an important aspect in public health. Water pollution is one main cause of worldwide diseases and death. Human activities around water catchment areas contribute to some level of stream pollution. Aora Loko stream serve communities living around Mabungo and Maseno town as a source of domestic water. This study aimed at determining the bacteriological and physicochemical parameters of the stream water in order to determine its suitability for human domestic use. Water samples were collected at four different sites. The sites were site A – Mabungo near Bosnia, Site B- university football field, Site C- near university farm where bathing and swimming activities take place, and Site D- near car wash area next to Kisumu-Busia road. Bacterial analysis of the water samples was conducted using standard methods on Nutrient agar. Bacteriological analysis identified four genera of bacteria of medical importance comprising of Escherichia, Salmonella, Streptococcus and Staphylococcus. There were significant differences (P≤0.05) among the physicochemical parameters determined. Generally the physicochemical parameters showed variation along the stream. Temperature values within sites A and B were 23.6 0C and 23.8 0C respectively while temperature values within sites C and D were slightly lower 22.8 0C and 22.6 0C. pH values ranged between 9.0 - 9.2, and therefore were found to be above the WHO/FEPA permissive limits 6.5 - 8.5. Water conductivity values ranged between 77.3- 77.7 μs/cm. BOD values for sites C and D were 3.4 mg/l and 3.0 mg/l hence below the permissive limits. The results indicated that the Aora Loko stream water is slightly polluted due to presence of coliforms