Research Article Physico-chemical and Bacteriological Assessement of Oyibo River in Ehime

The physico-chemical and bacteriological assessement of Oyibo river, Ehime Mbano, was carried out between 2011 and 2012. Considering the communities that make use of this river for different purposes, water samples were collected from four different sampling points along the river and subjected to physico-chemical and bacteriological analyses. Pour plate method was adopted to determine total heterotrophic bacteria, and membrane filtration technique, for total coliforms and E. coli counts. Standard procedures for water analysis by APHA were adopted for the determination of physical and chemical parameters. Atomic Absorption Spectrophptometer (AAS) was used to analyze for heavy metals. The average values of total heterotrophic bacteria were 5.8 x 103 cfu/ml and 1.51 x 103 cfu/ml for rainy and dry seasons respectively. Average values for total coliforms and E. coli counts were 33.75 cfu/100ml and 6 cfu/100ml for rainy season, and 17.38 cfu/100ml and 4 cfu/100ml for dry season. Bacterial isolates included E. coli, Salmonella spp, Lactobacilli spp, Klebsiella spp, Staphylococcus spp, Proteus spp, and Pseudomonas spp. In all the water samples, the pH values ranged from 6.04 – 6.52. Average values of total hardness for rainy and dry seasons were 5.90mg/l and 5. 43mg/l respectively. The concentrations of nitrate, phosphate, chloride, and sulphate ranged from 0.00 – 16.40mg/l; 0.01 – 1.24mg/l; 0.13 – 0.35mg/l; 0.00 – 15.95mg/l respectively. Average COD, BOD and DO values were 5.63mg/l, 2.07mg/l, and 3.17mg/l in dry season, and 9.24mg/l, 1.77mg/l, and 4.26mg/l in rainy season. The values of heavy metals during the rains were within the range of 0.0008ppm – 1.5605ppm, but 0.0001ppm – 0.0339ppm, in dry season. There were n