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Wastewater from different sources is contaminated by protozoan parasites including Cryptosporidium and Giardia . Many protozoan parasites are becoming resistant to chemical treatment. The challenge of finding alternatives is presented to researchers by exploring other methods of eliminating protozoan parasites from wastewater. The aim of this study was to assess the speciation and the viability of Cryptosporidium and Giardia in environmental samples with the specific objective of evaluating if effluent chlorination and UV affect the viability. Different doses of chlorine with different exposure times were experimented with both distilled water and waste water spiked with (oo)cysts derived from environmental samples. UV irradiation at different doses was also experimented using the same spiked samples. Two methods of quantification and detection, namely, microscopy and flow cytometry, were used in the experiment. Two vital dyes, Syto-9+PI and DAPI+PI, were the used for staining the collected wastewater samples. It was found that the (oo)cysts responded to chlorination and UV treatments with Giardia responding better than Cryptosporidium . Giardia responded very well to UV irradiations with almost 0 percent remaining viable after a low dose of UV. Cryptosporidium was found to be resistant to chlorination even at high doses but responded well to high UV doses. DAPI+PI dye gave a lower mean percentage viability values than Syto-9+PI. Flow cytometry gave higher mean percentage than microscopy from the results. It is concluded that UV is a promising alternative to Chlorine in removing Cryptosporidium and Giardia from waste water. Appropriate treatment method for wastewater is necessary to minimize water resources pollution when wastewater is released into water systems.

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Pollutants in stormwater are detrimental to the receiving water bodies. The study of pollutants in stormwater is important to know the appropriate management techniques to remove these pollutants. This paper presents an explorative study of runoff in Pretoria, South Africa. Common pollutants in stormwater are studied to determine their correlation with total suspended solids found in four different sites in Pretoria. The metals are strongly correlated with total suspended solids. It is suggested that treatment of pollutants by treating or removing solids may be extended to other heavy metals and nutrients to improve stormwater quality. In this study, some contaminants are identified to be associated with traffic volume. In this paper, the authors suggest that efforts should be made nationally and internationally to redesign vehicular products to eliminate the traffic contaminants in stormwater.