Study of Kosti Water Treatment Plant Operations During Different Seasons

Abstract

Some areas in Sudan suffer contamination in potable water. This study concerned with the problem of water contamination in Kosti water treatment plant. The objectives of the dissertation are to determine the efficiency and adjust the treatment process of producing good quality and standard drinking water. Samples were taken from the water treatment plant in different seasons to measure the turbidity, total suspended solids(TSS), residual chlorine, and bacterial count. The samples were analyzed using standard methods for the examination of water and waste water. Results showed that the average turbidity of water in summer season at inlet, clarifier, sand filter and storage tank was 18.33, 12.77, 15.27 and 17.5 NTU respectively, in autumn it was 302.77, 12.02, 15.23 and 75.03 NTU respectively and in winter it was 9.96, 11.5, 12.37 and 13.23 NTU respectively. These values exceeded the levels recommended by WHO (1993) and Sudanese Standards (5 NTU) it is observe that the records are slightly light in winter and summer, but are extremely high in autumn. Average results of TSS in summer were 7, 9, 7 and 6 mg/L, in autumn were 39, 43, 40 and 30 mg/l, in winter were 12.33, 18.66, 13.66 and 16.66 mg/l respectively. These values are high specially in autumn and should be minimized to the minimum possible. The result of bacteria taken from the storage tank showed that water is contaminated in autumn. High turbidity in autumn restricts adding chlorine, then the results of residual chlorine taken in summer and winter are found to meet the permissible level of Sudanese Standards (0.2-0.5). It is concluded that Kosti city drinking water is generally of inadequate quality and unsuitable for drinking and specifically in autumn. Also, the bacteriological quality needs reconsideration in all seasons but special, health and chemical considerations in autumn. The dissertation recommends upgrading the water treatment plant by increase efficiency of the internal system of coagulation, filtration and disinfection to meet the present and future Kosti town water demand.