[01] Bruce Roy Thulane Vilane, Department of Agricultural and Biosystems Engineering, Faculty of Agriculture, University of Eswatini, Luyengo Campus, P/B Luyengo, Eswatini. [02] Senele Titi Gama, Department of Agricultural and Biosystems Engineering, Faculty of Agriculture, University of Eswatini, Luyengo Campus, P/B Luyengo, Eswatini.

The demand for safe drinking water is continuously increasing globally, a situation that has led to the use of technologies that are safe, simple, efficient, and more importantly reduce the cost of water treatment. Slow Sand Filtration (SSF) is one of such technologies, which has attracted a lot of research interest from researchers. An experiment was conducted to determine the effect of SSF on the water quality of the Usuthu Forest Company Water Scheme in Eswatini (UFCWS). The experiment had the Usuthu Forest Water Scheme’s slow sand filtered water, as the treatment with three replications. Tap water from Eswatini Water Services Corporation (EWSC) was used as a control. Water samples were taken from the inlet and outlet of the SSF treatment unit for testing physical, bacteriological and chemical quality on the same day. Data analysis was conducted using standard error bars, compared against World Health Organization (WHO) drinking water quality guidelines. The results reflected that the mean pH of the SSF UFCWS was 7.14, 6.72, 6.80 before the SSF, after SSF, and the control, respectively. The turbidity was 24.00 NTU, 1.00 NTU and 4.47 NTU before SSF, after SSF and for the control, respectively. The colour also followed the same trend, as expected. The biological quality of the SSF water indicated that the total coliforms was 1001 counts per 100 ml before SSF, 10 counts per 100 ml after SSF, and the control had 3.39 counts per 100 ml. The faecal coliforms (E. coli) in the SSF water were 80 counts per 100 ml before SSF and 0.0 counts per 100 ml after SSF and the control. The chemical SSF water results indicated that the nitrates level was 2.73 mg/L before SSF and 2.43 mg/ L after SSF, whereas the hardness was 58.5 mg/L, 55.3 mg/L and 53.7 mg/L before SSF, after SSF and the control, respectively. It was concluded that the physical water quality of the SSF UFCWS was of acceptable quality. The bacteriological quality was also found to be acceptable as evident by the values that were below the WHO guideline (5 NTU) for drinking water quality. The chemical quality of the SSF water was acceptable as evident by the values, which were lower that the WHO guideline values for both parameters in question.

Effect, Slow Sand Filtration, Water Quality, Usuthu Forest Company Water Scheme, Eswatini

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