Assessment of Physicochemical and Microbiological Characteristics of Water Samples of Okomu National Park, Edo State, Nigeria

Water is very crucial for the survival and maintenance of most living organisms. The quality of water available for plant, animal or human use cannot therefore be compromised. This study therefore examined the physicochemical and microbiological characteristics of water samples in Okomu National Park, Edo State, Nigeria. Water samples were collected from four waterholes (three rivers and one stream) for two seasons (dry and wet) using grab sampling technique. These water samples were analysed for physicochemical [temperature, pH, total dissolved solid, electrical conductivity, total suspended solids, dissolved oxygen (DO), nitrate, chloride, phosphate, sulphate, biological oxygen demand (BOD) and chemical oxygen demand (COD)] and microbiological (total coliform and fungal counts) analyses using standard methods. Data collected were subjected to descriptive statistics and T-test at α0.05 and compared with WHO permissible limits. The result showed that the mean COD (both seasons) and BOD (dry season) were above the comparable WHO permissible limit while there was no significant difference in the values of all the physicochemical parameters across the seasons of sampling. Salmonella / Shigella and Staphylococcus aureus were observed to be absent while the total coliform and fungi counts were observed to be higher than the WHO permissible limit for drinking water. The detection of Escherichia coli in the water samples (except Arakhuan stream) is an indication of faecal contamination either of animal or human origin. There was significant difference in total heterotrophic bacteria (t=-4.936) and total coliform counts (t=-2.417) in the waters sampled. Constant monitoring of the waterholes and intensified sensitization of the surrounding communities on ecosystem conservation is needed to protect the park’s ecosystems.