POLLUTION INDEX OF SOME LAKES IN IBADAN METROPOLIS, OYO STATE, NIGERIA

¹Abiaziem, C. V. and ²Adewole, A.

¹Department of Science Laboratory Technology, Federal Polytechnic, Ilaro, Ogun State

²Department of Science Laboratory Technology, Federal Polytechnic, Ilaro, Ogun State

Email: vyvycox@yahoo.com

ABSTRACT

Lake water is a sink for different waste discharge and effluents; hence it is a good indicator of environmental pollution. Studies were carried out on the quality of some lake water in Ibadan to ascertain the extent of pollution. The following lakes were sampled and analyzed; Agodi, Awba, Eleyele and IITA lakes. In this regards, four sampling points were selected for each lake and the following parameters were analyzed; temperature, pH, total solids, total dissolved solids, total suspended solids, oil and grease, dissolved oxygen, biochemical oxygen demand, chemical oxygen demand, alkalinity, total hardness, nitrate, chloride, ammonia, sulphate and phosphate using standard analytical methods. The results of the analyses showed that the pH of the lake water ranged from 8.0±0.02 to 8.3±0.05. Other values of range are: Total Solids – 330±26 to 730±51mg/L; DO-1.93±0.06 to 7.64±0.46mgO₂/L; BOD – 5.7±0.4 to 11±1.0mgO₂/L; COD – 130±5.3 to 160±9.2mgO₂/L; Total hardness – 99±2.2 to 160±3.7mg CaCO₃/L. The results of the analyses indicate that most of the physico-chemical parameters of the water sample were within the WHO and Federal Environmental Protection Agency (FEPA) maximum permissible limits for drinking water. They are not high enough to be hazardous.