The changes in water quality parameters were monitored from May 2008 – April 2009 in Ogbei Stream, Anambra State, Nigeria. Water samples were taken from study stations twice every month. The samples were transported to laboratory for analysis. Physico-chemical parameters were determined using standard methods. Temperature, water velocity, depth, transparency, conductivity and pH were determined in the field while dissolved oxygen, alkalinity, hardness, nitrate-nitrogen, phosphate-phosphorus and total dissolved solids were determined in the laboratory. The result revealed that air temperature, water temperature, water velocity, depth, transparency, conductivity, pH, dissolved oxygen, alkalinity, hardness, nitrate-nitrogen, phosphate-phosphorus and total dissolved solidsranged from 27.0-31.8C (29.980.08C), 25.9-29.8C (28.140.08C), 0.13-0.55 ms-1 (0.280.01 ms-1), 0.19-0.56m (0.350.06 m), 14.00-40.60 cm (28.030.93 cm), 0.01-0.17 μmhos/cm (0.050.00 μmhos/cm), 4.30-7.50 (5.470.05), 3.03-6.95 mg/l (4.990.04 mg/l), 0.01-20.10 mg/l CaCO3 (4.600.38 mg/l CaCO3), 0.00-23.10 mg/l CaCO3 (4.880.37 mg/l CaCO3), 0.00-0.01mg/l (0.040.0l mg/l), 0.30-8.40 mg/l (3.670.13 mg/l) and 0.01-12.40 mg/l (1.440.22 mg/l) respectively in various months. The dry season mean values for temperature, transparency, alkalinity, phosphate-phosphorus and total dissolved solids were significantly (p<0.05) higher than those for the rainy season. However for water velocity, depth, pH and dissolved oxygen, the rainy season mean values were significantly higher than the dry season mean values. The concrete structure, effect of deforestation and fertilizer application were among the factors that might be responsible for the fluctuations of the physic-chemical parameters determined in the stream.
Keywords: Water Quality, Parameters, Concrete Structured Stream