Seasonal Variation in Water Quality Parameters of the Kaduna River in Kaduna State

Inland water bodies in Nigeria face increasing pressure from agricultural expansion, urban growth, and industrial discharge, making regular water quality assessments essential for ecosystem management. This study examined the seasonal variation in physicochemical water quality parameters of the Kaduna River in Kaduna State, North West Nigeria. Sampling was conducted bimonthly across six stations spanning the urban and peri-urban sections of the river over a twelve-month period. Parameters including temperature, pH, dissolved oxygen, biochemical oxygen demand, turbidity, total suspended solids, nitrate, and phosphate were measured in situ and in the laboratory following APHA standard methods. Results showed significant seasonal differences in most parameters, with dissolved oxygen declining markedly during the dry season. Turbidity and total suspended solids peaked during the wet season due to surface runoff and erosion from adjacent farmlands. Biochemical oxygen demand values exceeded WHO permissible limits at three stations located within the urban stretch. Nitrate and phosphate concentrations were highest near the textile and tannery industrial zones. Principal component analysis identified agricultural runoff and industrial effluent as the primary drivers of water quality deterioration. Dissolved oxygen showed a strong negative correlation with BOD, confirming organic pollution at industrial stations. The study recommends effluent pre-treatment requirements for industrial operators and riparian vegetation restoration as management interventions for the Kaduna River. Keywords: water quality, seasonal variation, Kaduna River, physicochemical parameters, industrial pollution.