ABSTRACT

This study was conducted in Obazuwa Lake, Benin City, Edo State, Nigeria, aimed at investigating the Physico-chemical and Microbial characteristics of water in Obazuwa lake. Three sampling stations were selected. Water samples were collected in 3 replicates monthly. Eighteen (18) Physico-chemical parameters including air and temperature, depth, pH, Electrical Conductivity, Total Suspended Solids, Dissolved oxygen, Biochemical Oxygen Demand, Chlorine (Cl^-), Calcium (Ca), Nitrate (No₃)_, Suphate (_SO4), Phosphate (PO₄), Iron(Fe), and Maganese(Mn) were analyzed using standard methods. Iron and manganese were the only two Physico-chemical parameters with significant difference(p<0.05) among all the physicochemical Parameters of the stations. The Microbial characteristics of the water showed that all the three stations harboured large amount of coliform with station 1 having the highest average mean of 676 while station had the lowest amount 444. E. coli, fungi and Strept. faecalis where the indicator organism used to determine the fitness and pollution of the water. The highest monthly E. coli concentration value was recorded 150mg/l in March 2022. while the lowest E. coli concentration value was recorded 0.57mg/l in February 2022.For fungi the monthly highest and lowest number of organisms was recorded as 15mg/l which Occurred in station 2 in February 2022 and 12mg/l in station 3 in January 2022.Hence from the study Obazuwa lake is seen to be polluted and unfit for drinking, and the presence of the high concentration Iron and manganese is the sole reason for the discoloration and metallic taste of the water.