Physicochemical and bacteriological quality of water collected from dams and rivers along gold mining sites in Zamfara State

Abstract

The physicochemical properties of water such as pH, temperature, conductivity, total dissolved solids, total suspended solid, alkalinity, dissolved oxygen, chloride, turbidity, hardness, sulphate, chemical oxygen demand and biochemical oxygen of the three major dams and rivers in Zamfara State were analyzed using standard analytical methods. The influence of seasonal variability on the parameters was also considered. Bacteriological assessment was also conducted to determine the bacteria load of the water bodies. The total bacterial counts obtained during the wet season (3.6 x 10⁶ to 8.9 x 10⁶) were generally higher than those obtained in the dry (2.4 x10⁵ to 7.9 x 10⁵). The microbial values recorded in the dam which ranged from (2.4 x10⁵ to 7.4 x 10⁶) and rivers (5.2 x10⁵ to 8.9 x 10⁶) water body represent high bacteria load compared to the recommended standards for drinking water (WHO, 2008; EPA, 2010; USEPA, 2002). The result of the physicochemical parameters revealed marked variations and non-uniform distribution from one season to another for two years of study. The results further showed that pH, temperature, EC, TDS, TSS, alkalinity, DO, BOD, COD, Cl, and SO₄ have values that fall below the USEPA standard limit for drinking water with exception of turbidity (88.67 mg/l) that has a value higher than the recommended standard limit. Analysis of variance on the data collected revealed that there were significant difference (P < 0.05) between the parameters based on locations and seasons. Multiple range test conducted on the parameters also showed a significant difference between the wet and dry seasons. A combined mean of the parameters further revealed a significant different between the years.