Management of Industrial Effluents

The work involved field survey of industries producing and discharging effluents in the study area (Ado Odo/ Otta industrial zone of Ogun State, Nigeria);. Primary data were also collected for analysis using structured questionnaires and oral interviews to elicit the contribution of the industries to water pollution. QUAL2K was operated as a one-dimensional steady state and completely mixed system for hydrogeometric and water quality analysis on the Atuwara River. The 10.81 km long stretch from upstream at Owode ¿ Ijako to Iju Water Works was mapped with geographical positioning systems (GPS) and divided into 7 reaches with further segmentation of 0.3 km each from where grab samples were collected routinely throughout the study period. The result showed that the effluents were acidic in both seasons with range between pH 5.4 - 6.7. The BOD and COD concentration were also very high especially at immediate downstream of points of discharge.. The assimilative capacity of the river is very high because of the contribution from the tributaries. Calculated worst scenario of BOD discharge was about 12 metric tonnes per day. The heavy metals (cadmium, lead and iron) were above the limit