Impact of industrial effluents on Alaro river in Oluyole industrial estate, Ibadan and its suitability for aquatic life

Abstract

Human activities involving urbanization, agricultural development, overuse of fertilizers, inadequate management of land use and waste disposal can affect the quality of water and making it unfit for both aquaculture and domestic purposes. Thus, overexploitation and its attendant pollution is dangerous and threatening to spoil freshwater and aquatic ecosystems. Hence, this study was designed to evaluate quality of water around an industrial area in order to assess its suitability for aquatic life and to evolve policies for use and protection of water resources. A total number of thirty (30) water samples were collected from six (6) different sites and were subjected to hydrochemical analysis using various standard methods to determine their conformity to World Health Organization (WHO) maximum allowance concentration. As against the WHO recommendation of absence of colouration for drinking water, the water samples were not all colourless but had varying colours ranging from light green to greenish brown. The mean values of Conductivity (387.27uS), pH (7.38), Total Suspended Solids [TSS] (423.87mg/L) and Total Dissolved Solids[TDS] (212.97mg/L) fall within the WHO standard, those of Salinity (0.18%), Turbidity (149.00 NTU), Biochemical Oxygen Demand[BOD] (106.80mg/L), Chemical Oxygen Demand[COD] (187.10mg/L) and NH₄ (4.44mg/L) were higher than the WHO standard while Dissolved Oxygen[DO] (3.49mg/L) and CL^-(39.48mg/L) fall below the standard. These parameters make Alaro river unsuitable for aquatic life (fish) and therefore recommended that government and other stakeholders should take overdue steps in the development and implementation of waste water and industrial effluent receiving facilities in order to prevent discharge of untreated effluents into water bodies.

Keywords: Fresh water, Hydrochemical, Pollution, Standard, Urbanization