ABSTRACT

The effect of pulp and paper mill effluent discharge on water quality at Imo River Owerrinta was investigated. Sample collection was done twice a month, from the month of August to September 2008. The studies on water quality were carried out at four sampling stations. Sample A was located up stream. Sample B was effluent, Sample C was point of discharge, about 1km from up stream and sample 0 was down stream, about 3.5km from sample A up sream.Physcio-chemical parameters used in assessing water quality include temperature, pH, turbidity, dissolved oxygen, biochemical oxygen demand, total suspended solid, total hardness, and nutrients such as nitrate, and sulphate and heavy metals such as lead and zinc, were analyzed according to American Public Health Association. (APHA). The biological aspect of the study was based on the phytoplankton abundance. A-i- way (ANOVA) showed that there is significant different (P<O.05) across the parameters and samples. For the phytoplankton analysis, sample A which is down stream had the highest abundance of Cyanophyta, Bacillariophyta and Chlorophyta. Sample C point of discharge had the least abundance and effluent had no phytoplankton. The result obtained for the study shows that Imo River Owerrinta is under pollution stress due to the pulp and paper mill effluent discharge on the River.