Chemical Analysis of Freshwater Bodies in the Kumasi Metropolis and Its Environs, Ghana

Abstract

One of the main environmental problems facing the city of Kumasi the second largest city in Ghana over the years has been the pollution of water bodies arising from anthropogenic activities. This has become a potential health threat to the inhabitants of the city which was formerly referred to as the garden city of Ghana and its environs. The most affected are the surrounding rural areas that rely solely on the rivers for drinking, domestic and agricultural purposes. This study focused on the extent of chemical pollution of these water bodies through the determination physicochemical parameters such as pH, temperature, conductivity, total dissolved solids (TDS), Total suspended solids (TSS), alkalinity, Total hardness, nitrates, sulphates as well as heavy metals and biological contamination through the determination of total coliform and Escherichia coli. Eight samples were taken from three main rivers in the Kumasi metropolis namely Wiwi, Sisa and Subin. This data showed variations in the parameters in the samples as follows: pH, 6.67-7.50; temperature, 28-29°C; electrical conductivity (EC), 220-2120 mS/cm; TDS,10-1800 mg/l; alkalinity, 24-124 mg/l; total hardness, 25-365 mg/l; nitrates, b/d-0.47 mg/l; sulphate,0.352-40.30 ; phosphates, 5.2-30 mg/l; Pb, 6.620-6.797 mg/l; Fe. 14.81-45.65 mg/l; Mn, 0.726-4.7427 mg/l; Cd, 0.156-0.219 mg/l; Cr, 0.03-0.10 mg/l; Ni, 0.002-0.018 mg/l; Cu 0.113-2.258 mg/l and Zn 0.368-5.255 mg/l.  However, all the results obtained for the levels of the metals exceeded the EPA Maximum contaminant level (MCL) with the exception of the zinc where only one of the samples exceeded the MCL level.

Keyword: environmental, chemical pollution, Maximum contaminant level, physicochemical parameters, Kumasi-Ghana