Physiochemical and bacteriological analysis of surface water in Ewekoro Local Government Area of Ogun State, Nigeria: Case study of Lala, Yobo and Agodo Rivers

Abstract

This study examined the physiochemical and bacteriological analysis of surface water in Ewekoro Local Government Area of Ogun State, Nigeria - a case study of Lala, Yobo and Agodo Rivers. Water samples were collected from the rivers in October and December 2008. The samples were analyzed for pH, TDS, TH, electrical conductivity, chloride, calcium, nitrate and fecal coli form. Result indicated that total alkalinity, total hardness, calcium, nitrate and calcium carbonate were above maximum permissible limit of National Administration for Food, Drugs and Control (NAFDAC), Standard Organization of Nigeria (SON), United States Environmental Protection Agency (USEPA), European Union (EU) and World Health Organization (WHO) for drinking water in some sections of the rivers during certain period of the year. The rest of the parameters measured fall within these limits. The bacteriological analysis showed that Escherichia coli were present in all the rivers in October while only Lala River is free from E. coli in December. All the samples showed no growth of salmonella under the period of investigation. The implication of these results is that the rivers pose a health risk to the rural communities who rely primarily on them as the only source of domestic water supply. Key words: Surface water, rivers, water samples, Ewekoro Local Government.