Assessment of Surface Water Quality in Zaria Metropolis: Implications for Environmental Health and Sustainable Management

Abstract

Surface water bodies, including rivers, dams, and lakes, are integral to urban development and human life, supporting both urban residents and rural agricultural sectors. However, rapid population growth, urbanization, and industrialization have posed significant threats to water quality worldwide. Industrial discharges, in particular, contribute to water pollution, notably with toxic heavy metals. Assessing water quality involves monitoring various physicochemical parameters, which can be laborious and challenging. Therefore, this study employs statistical correlation analysis to understand the interrelationships among water quality parameters, aiming to simplify water quality assessment. Water samples were collected from Shika, Galma, and Ahmadu Bello University (ABU) dams in Zaria, Nigeria, and analysed for various parameters. Results showed that dissolved oxygen (DO) levels ranged from 1.37 to 3.67 mg/L, biochemical oxygen demand (BOD) ranged from 0.47 to 1.83 mg/L, and pH varied from 4.33 to 6.93 across different sampling points. Turbidity ranged from 65.27 to 152.20 NTU, total dissolved solids (TDS) ranged from 30.67 to 956.33 mg/L, and total suspended solids (TSS) ranged from 16.67 to 170.00 mg/L. Electrical conductivity (EC) varied from 62.97 to 1888.33 µs/cm, alkalinity (ALK) ranged from 14.00 to 28.00 mg/L, and chemical oxygen demand (COD) ranged from 93.30 to 123.30 mg/L. Sulphate (SO₄) concentrations ranged from 381.70 to 568.30 mg/L, nitrate (NO₃^-) ranged from 9.00 to 26.00 mg/L, and phosphate (PO₄) ranged from 0.12 to 0.61 mg/L. Statistical analysis revealed significant correlations among these parameters, indicating complex relationships within the aquatic ecosystem. Additionally, the analysis of variance (ANOVA) showed significant differences in water quality among sampling points, suggesting the influence of diverse pollution sources. Furthermore, the Water Quality Index (WQI) was calculated to assess the overall water quality status, indicating poor to unfit conditions for consumption across the studied locations. These findings underscore the urgent need for effective water management strategies to safeguard surface water quality for current and future generations.