The physico-chemical and bacteriological analyses of four rivers namely: Ajali, Obinna, Karawa and Adada in Ezeagu and Uzo-uwani Local Government Areas (LGAs) of Enugu State, South-eastern Nigeria, were carried out to evaluate their suitability for consumption. Water samples from Ajali River were taken from a point where the river receives brewery effluents and other two points that were impacted by non-point pollution sources. A total of 54 water samples were collected during the dry season, early rainy season and rainy season proper for 2 years. For each trip, nine samples were collected from three sampling points in Ajali and two each in Adada, Obinna and Karawa. The water quality index (WQI) was calculated using the arithmetic index method. Significant seasonal and spatial variations (p < 0.05) were evident for sulphate, phosphate, sodium, magnesium, pH, total alkalinity, nitrate and total dissolved solids. Mean values of WQI were 71.75 ± 16.07 57.26 ± 5.39, 60.47 ± 13.12, and 66.75 ± 15.30 for Adada, Obinna, Karawa and Ajali, respectively.
Keywords: Agriculture; Effluent; Monitoring; Pollution; Rivers; Water quality.