ABSTRACT:

This study assessed the physico-chemical parameters of Safa Reservoir, Kiyawa Local Government Area, Jigawa State, Nigeria. Water samples were collected monthly from three sites (A, B, and C) from January to June 2024. Parameters analyzed included temperature, turbidity, electrical conductivity, total dissolved solids (TDS), pH, dissolved oxygen (DO), biochemical oxygen demand (BOD), nitrates, and phosphates. In situ measurements were taken for temperature, pH, DO, turbidity, and conductivity, while BOD, nitrates, and phosphates were analyzed in the laboratory using standard methods. Two-way ANOVA was used to assess variations across sites and months. Results showed significant seasonal and spatial variations in the reservoir’s water quality. Temperature varied significantly across months (p < 0.05), peaking in April–June, but showed no significant difference among sites (p > 0.05). Turbidity, pH, DO, nitrates, and phosphates exhibited significant variations among sites, months, and their interactions (p < 0.05). DO was significantly higher in January and March at site A, while nitrate levels peaked in June across all sites. Phosphate was highest in May (sites A and C) and June (site B). However, electrical conductivity, TDS, and BOD showed no significant variations (p > 0.05). The correlation analysis revealed significant positive relationships among the physico-chemical parameters of Safa Reservoir. Temperature showed a strong positive correlation with phosphate and BOD. Transparency was positively correlated with TDS and pH, while TDS and nitrate, as well as phosphate and nitrate, also exhibited highly significant positive relationships. Findings highlight seasonal influences on water quality, emphasizing the need for continuous monitoring to ensure ecological sustainability and water usability.