Effects of Industrial Effluents and Municipal Wastes on Water Conductivity and Total Dissolved Solids, Sulphate and Phosphate Ions Concentration of Ogba River, Benin City, Nigeria

The effects of industrial effluents and municipal wastes on the Water Conductivity (WC), the Total Dissolved Solids (TDS), the Sulphate (SO42-) and Phosphate (PO43-) ion concentrations of Ogba River, Benin City, Nigeria were studied. There were significant differences (p< 0.05) in the values of WC and TDS of the river sampled at four stations [Waterworks (1), Off-Trade-fair Center, (2) 50m to Drainage Point (3) and Drainage Point (4)] and recorded between September 2004 and April, 2005. Whereas the values of SO42- varied significantly (p>0.05) according to the months sampled (September-April), no such significant variations were recorded due to the sampled stations. The highest value of SO42- (0.19±0.02 mg L 1) was recorded in March, while those of PO43- (0.58±0.03 mg L 1), WC (66.63±0.23 S cm 1), TDS (30.57±0.15 mg L 1) were recorded in January. The least mean value of SO42- (0.07±0.02 mg L 1) was recorded in January while the least value of PO43- (0.27±0.01 mg L 1) was recorded in April. Both the least values of WC (33.41±0.15 S cm 1) and TDS (15.80±0.80 mg L 1) were recorded in February. The trend in the seasonal variations of WC and TDS values of the river indicates that there is a functional parity between the two water quality parameters owing to the contamination of the river with industrial effluents and municipal wastes. The high TDS values of the river at the drainage point in September might be due to a build-up of solutes arising from the inflow of effluents, wastes and surface run-offs caused by increased rainfall. The range of PO43- values (0.12±0.01 to 0.59±0.04 mg L 1) between the dry and wet seasons (January to September) were within comparable limits with the results of other workers recorded in the River Niger. The accumulation of SO42- and PO43- ions at Stations 3 and 4 than at Stations 1 and 2 might have resulted in some adverse effects on the physical, chemical and biotic components of the river. This might be the reason why no fishes were found in those areas.