IMPACT ASSESSMENT OF CASSAVA EFFLUENTS ON BARIKA STREAM IN IBADAN, NIGERIA

Experimental study on the effects of cassava effluent on th e receiving Barika stream is presented. The work involves the examination of the physicochemical and microbial properties of the cassava polluted stream. Samples of the polluted water were colle cted from three points, the discharge, upstream and downstream points. The temperature increased by 10.9 % from upstream to discharge point, it then decreased by 9.1% from discharge point to downst ream point. Similar trends were observed for other properties except dissolved oxygen and the pH . The pH decreased by 18.9% from upstream to discharge point, and then increased by 9.4% from di scharge point to downstream point. The organisms identified are in the categories of aerobes, col iforms and mould (fungal). The total aerobic/viable count, total coliform count and total mould count w ere highest at the discharge point and lowest at upstream point. The values of the physicochemi cal properties at the discharge point did not meet up with the landfill disposal criteria and the effluent limitation guidelines. Analysis of the experimental results showed that the cassava effluent adverse ly modified the properties of the Barika Stream. Treatment of cassava effluents before discharge into t he water body should be adopted. A cassava effluent and water quality monitoring program should be develope d and implemented.