M.Sc. (Geography) / The Crocodile River drains a highly developed catchment, with 25% of the South African Gross Domestic Product (GDP) being produced in the Crocodile-West Marico Water Management Area (WMA). The industrial, agricultural and mining sectors that mostly contribute to GDP are however greatly dependent on the water resources within the Crocodile-West Marico WMA and therefore it is important to monitor the status of these water resources carefully. This study aimed to determine whether there is a positive correlation between changes in land-use and changes in water quality in the Crocodile River catchment area across both a spatial and temporal scale. Water quality was defined by measurement and analysis of both pure quantitative changes in water quality parameters as well as qualitative changes in water quality as related to the end use of the water. In general water quality in the study area, as measured in terms of the variables used for this study, was found to still be within acceptable range for domestic use, irrigation, livestock watering and Industrial Cat. 3 and 4 water uses. The majority of variables were however above the Aquatic Target Water Quality Range (TWQR). In terms of aquatic ecosystems, the study area is however not very sensitive with only a few catchments and sub-catchments classified as freshwater ecosystem priority areas. The freshwater ecosystem priority areas are also located in mostly the upper catchment where water quality is generally fair to good i.e. as confirmed by water quality results from Water Monitoring Stations (WMS) 90195 and 90165. It was confirmed that spatial and temporal changes in land use had a definite impact on physical and chemical water quality as measured at each WMS. The variables used to determine water quality changes due to land use change were however not ideal to determine certain land use impacts. Urban, industrial and mining impacts would for example have been easier to identify by means of metal and heavy metal concentrations as well as other toxic organic and inorganic constituents. To this extent it was a challenge to link specific industries or industrial areas to water quality changes. This was mostly due to the fact that industrial processes differ vastly, with a range of pollutants being emitted and discharged into the environment. It was however evident from the results that nutrient enrichment mostly originates from point sources, specifically Wastewater Treatment Works (WwTWs), and that salinization is mostly caused by intensive crop irrigation. Build-up or urban areas mostly resulted in lower levels of salts and dissolved solids, possibly due to limited exposed ground surfaces. It was further found that mining related to Platinum Group Metals (PGMs) resulted in and increase chloride, dissolved major salts, electrical conductivity, total hardness, potassium, magnesium, sodium and sulphate concentrations...

All natural waters containing particulate matter, such as clay, silt, colloidal particles, plankton / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2007

M.Sc. / Victoria Lake also known as Germiston Lake is an urban impoundment which is situated east of Johannesburg. This Lake is used for a number of recreational activities and can be viewed as an important feature of this area. It is a natural perennial pan and has several inlets (inflows) which drain a part of Germiston's business area and surrounding residential areas. In the past various studies have focused on the water quality as well as other aspects of the ecology of the Lake that may influence recreational activities and the physical-chemical quality of the water. However, information on the physical-chemical quality of the inflow water is poorly investigated and needs further attention. This study gathered further data on the water quality and associated problems within the major inlets to the Lake. Six inlets were monitored monthly for a year. The water samples that have been collected were analyzed for several physical and chemical constituents. In general it seemed as if the waters of the inlets around Victoria Lake were more polluted in comparison to the surface waters of the lake Sites 1, 4 and 5 seemed to be the most polluted inlets and it should be closely monitored in future. Most of the water quality constituents that have been compared with the water quality criteria exceeded the acute effect values given by the South African Water Quality Guidelines. Waste is thus continually dumped into the Victoria Lake via the major inlets resulting in water pollution. The quality of this resource is therefore diminishing rapidly. If Victoria Lake is to be successfully used and managed in order to limit the impact on the environment, all further development and management should take place in terms of sustainable development.

Freshwater of acceptable quality is crucial for certain needs and uses such as recreational, domestic and industrial activities (Bartram and Balance, 1996). Water contamination and excessive use and abuse of the fresh water environment, threaten development as well as a variety of other life aspects and make water assessment necessary for safe drinking water delivery. It has been proven that water of good quality is important to sustain development (Karolina et al., 2011). South African freshwater resources such as lakes, rivers and groundwater, undergo intense stress owing to a rapidly expanding population, a growing economy, severe pollution from various industries, a possible effect of global warming and an increase in droughts (Oberholster et al., 2008). A study done by Boyd (2010), further confirmed the decline in water quality of these resources due to excessive contamination caused by urban development, human activities, industrialisation, forest establishment, agriculture and mining operations. For this project, the analysis of physical, chemical and biological parameters of the water from Lake Nsezi was used to assess the water quality of the lake. Results from the analysis were compared to Target Water Quality Range (TWQR) of the Water Quality Guidelines for the Aquatic Environment (WQG/AE) and for Domestic Use (WQG/DU). A further comparison was done between data from the current study and available historical water quality data of Lake Nsezi. From the results for this project and historical data, it was evident that parameters such as total dissolved solids (TDS) and chloride, metals such as aluminium, cadmium, copper, lead and manganese, and total coliform counts were above the TWQR for the WQG/AE and WQG/DU at most of the sampling sites. / Environmental Sciences / M. Sc. (Environmental Science)

The deteriorating water quality in South Africa and changing legislation requiring the industrial implementation of waste minimisation and pollution prevention technologies has highlighted the need for the investigation of new effluent treatment technologies such as advanced oxidation processes. This investigation details the evaluation of ultrasound, an emerging advanced oxidation process, to degrade organic compounds during water treatment. The objectives of the investigation included the design of a suitable ultrasonic laboratory reactor to investigate ultrasound chemistry and the sub-processes occurring during sonication. Atrazine was used as a model compound to compare the performance of ultrasound with that of ozone and hydrogen peroxide, already established advanced oxidation processes. Recommendations have also been made for the scale-up of ultrasonic processes. A 500 mL ultrasonic cell containing an ultrasonic horn as an energy source was designed and constructed. The measurement of hydrogen peroxide concentration was used as a tool to indicate the process conditions under which the formation of free radical reactions during sonication are enhanced. These include the application of oxygen and air sparging or the addition of a commercial source of hydrogen peroxide. It was found that oxygen sparging and a high acoustic power input should be used in ultrasonic processes with a short retention time, and conversely, that air sparging and a lower acoustic energy source should be used in processes with a long retention time. A flow loop system should be considered to maximise oxidation both within and beyond the sonicated zone, gas sparging should only occur within the sonication zone else the degradation of hydrogen peroxide is encouraged. Ultrasound is most effectively applied in water treatment as a pretreatment stage in combination with other technologies and not as a stand-alone process. Atrazine was used. as a model compound to compare the performance of ultrasound with ozone because of its persistence in the environment and resistance to degradation. Atrazine was degraded during sonication and ozonation. degradation increased wim the addition of hydrogen peroxide. Ozone decomposition (and hence free radical reactions) was enhanced when ozone was combined with ultrasound or hydrogen peroxide. Enhanced ozone decomposition during ozonation combined with sonication is due to the conditions (high temperatures and pressures) as well as the free radical reactions occurring within the collapsing cavitation bubbles and at the gas-liquid interface. The enhancing effect of combining ultrasound with ozone was greatest at the low ozone concentrations typically applied during water treatment. Atrazine degradation during sonication and ozonation is predominantly due to the reaction with hydroxyl radicals. Atrazine degradation products identified using gas chromatography and mass spectrometry were deethylatrazine. hydroxyatrazine and deethyldeisopropylatrazine (tentatively identified). / Thesis (Ph.D.)-University of Natal, Durban, 2001.

Amongst others, the South African National Water Act No. 36 of 1998 acknowledges that access to sufficient safe and clean water is a basic right to all South Africans. However, it is well known that millions of inhabitants of rural communities in South Africa are still deprived of this right. Many rural communities in South Africa are thus consuming unsafe, untreated water everyday, thereby exposing themselves to waterborne diseases. The main reason of concern however is the fact that, nevertheless, little is known about rural water quality in South Africa as most water quality work is being undertaken in urban areas. The study's aim is twofold: first, the study examines the impact of Black rural communities' land-use and related activities on water quality and second is specifically, to study the washing practices of the rural communities in the upper Kat River area. To understand the potential impacts of the upper Kat River Black village communities and their associated land-use practices on the quality of upper Kat River catchment, prominent land-use and related activities in the area were investigated. Study area maps were studied and field surveys undertaken to observe major land-use and related activities in the area. The results of the study show that most used land in the area is being utilised for agricultural activities. Settlements and commercial forestry also occupy considerable areas of land. The literature survey suggests that such land-use could have a considerable degrading impact on the quality of both surface and groundwater. The study also investigated the impact of the in-stream use of detergents on water quality in the upper Kat River valley, Eastern Cape - South Africa. In-stream washing practices of certain communities in the upper Kat River valley were investigated and the impact of detergents on water quality was assessed. Recovery of the flow from the input of detergents was also measured. During the study, it has been ascertained that doing laundry by the stream is the common practice in the study area. Water quality analysis results show a remarkable increase on the levels of chloride, turbidity, and electrical conductivity in water as a consequence of direct input of detergents practice into the river during the washing. The recovery of the water quality at a distance of 1km from site of input was almost complete. Water quality monitoring programme was undertaken to establish a link between land-use and the quality of water. In a water quality study routine carried out for a period of 40 weeks on a twice monthly frequency, the state of the flows of the river was determined; water samples were collected at pre-determined points; and the in situ analysis of selected water quality variables (with the exception of the faecal coliforms whose analysis was carried out in the biotechnology laboratory) was carried out. Results of the study showed that the concentration of the studied water quality variables in the area varied widely with time. A clear distinction in concentration of variables such as electrical conductivity, turbidity, pH, total hardness, chloride, and nitrate was evident at the high compared to the low flow period of the study. The concentration of the studied water quality variables in the upper Kat River catchment area also seemed to vary over space. The concentration of variables such as electrical conductivity, pH, total hardness, chloride, nitrate, potassium, number of faecal coliform bacteria per 100ml was observed to be higher in most of the tributary streams than the main river. Turbidity however was orders of magnitude higher in the Kat River than the rest of the tributaries. Most importantly however, results of the study showed that there is a strong link between the quality of water and land-use and related activities in the area. The spatial results of the study showed a strong connection between some land-use and the concentrations of water quality variables. For example, areas of intense grazing were noted with high concentrations of nutrients like nitrate and a higher number of faecal coliform bacteria per 100 ml of water. It was established during the study that land-use and related activities in the upper Kat River valley are negatively impacting on the quality of water thereby rendering it less fit for use for domestic purposes. The continued use of the polluted water by the communities is thus accompanied by a danger of the outbreak of waterborne diseases like cholera. When the concerned communities met in a workshop to discuss the issue of quality of their water, they committed themselves to: • shunning water polluting activities, • at least boiling their drinking water before consuming it. The communities also requested a meeting with the Department of Water and Forestry officials to request a treated, piped supply of water. / KMBT_363 / Adobe Acrobat 9.54 Paper Capture Plug-in

M.Ing. (Civil Engineering) / To relieve the extreme pressure placed on overburdened water and wastewater infrastructure, the reuse of light wastewater was identified as a possible source of water supply for non-potable applications. The light wastewater discharge intercepted on-site can be recycled, treated and thereafter distributed to fixtures for agricultural, sanitation and gardening based activities. Sources for this light wastewater stream includes bathroom showers, bath tubs, hand wash basins including that of kitchens, laundry and washing machine outflows of recyclable quality. This type of re-usable water is called greywater (GW). This on-site re-use concept has potential to offer greater potable water savings if correctly implemented. For the purpose of this research, this particular type of waste stream excluding the kitchen and laundry discharge was the water source considered for the supply to this greywater treatment plant (GWTP). In 2009, the Water Research Commission (WRC) funded a greywater pilot study in a joint venture between the University of Witwatersrand (WITS) and the University of Johannesburg (UJ). Over the last few years, this project had progressed with new outcomes each year. The pilot GWTP at Unit 51, Student Town, UJ in Auckland Park was used for the purpose of this study. The selected reuse application for the GW effluent was for toilet flushing. GW was supplied to two toilets in a residential student complex housing 16 female and male students i.e. 8 students on each floor. The highlights of the WRC study included: a lack of satisfactory treatment efficiency and a well-defined protocol to address the problems associated with the slightly poor quality of effluent produced (i.e. unpleasant odours, greyish appearance and the unacceptable microbial count). Determining and addressing the user perceptions and user education about GW usage, respectfully, was a significant component in the successful management of the project. In this report, a practical evaluation of three crucial components of the GWTP was completed. These three components viz. treatment efficiency, user perceptions and quality standards, were common aspects of concern for existing decentralised GWTP’s within residential or small commercial stands.

M.Sc. / The goal of this study is to determine the relationship between landuse and runoff water quality. The chosen study area is the Roodeplaat Dam drainage basin. The basin contains three subbasins with varying characteristics. The western subbasin is that of the Hartbees Spruit with a largely urban character. The eastern subbasin containing the Edendal Spruit has mostly rural characteristics in terms of landuse. The central (and largest) sub-basin of the Pienaars River has a mixed (urban/rural) land usage. Specific aims of the study were the determination of the negative (or positive) influence of urban landuse on the quality of water that flows into the Roodeplaat Dam, and the determination of the influence of climate (more specifically precipitation) on this water quality. A review of different water quality components is provided with the emphasis on those used in the study. Each of the three subbasins are described in terms of landese to determine the possible influences on water quality. Water quality data obtained from the Department of Water Affairs (Pretoria) were calculated to fortnightly averages in order to obtain complete time series. Six inorganic water quality indicators (total dissolved solids, pH, magnesium, fluoor, sulphate and calcium carbonate) were chosen out of the initial sixteen obtained. The selection that was made was based on the results of a pre-analysis long term trend analysis (for a five year period) of the water quality indicators in each of the three sub-basins. Chosen data sets were compiled to fortnightly and seasonal averages to be used in the analysis phase. The seasons used were determined by combining precipitation and inflow contributions (to the Roodeplaat Dam) for a ten year period. Each of the six chosen water quality indicators were examined in terms of absolute data (fortnightly averages), seasonal averages and long term trends for the fifteen year study period. Time and spatial aspects were integrated to make the sinthesis of the study possible. Albeit some unique conclusions were made, the initial aims of the study could still be reached. It was determined that urban landuse has a more negative influence on the water quality of the Roodeplaat Dam drainage basin than rural landuse (in this case mostly small holdings). Apart from this it was shown that climate (in the form of precipitation) has an even bigger influence on water quality (pollution concentration levels) in the Roodeplaat Dam drainage basin.

Water quality is concerning as many still lack access to safe drinking water. Alternate sources such as rivers (FC up to 1600 CFUs/100 mL) and rainwater are often polluted. Rainwater tanks require maintenance to improve water quality, but could be used for non-potable purposes or irrigation. Grahamstown infrastructural failures initiate deviations from DWAF 1996 domestic water guidelines for microorganisms within the distribution system. Frequent testing can decrease risks of waterborne diseases. Limitations to this are inaccessibility of rural areas, distances from testing centres and costs. The low cost H2S strip test able to be used onsite by communities, may aid in risk assessment. H2S strip test results are not affected by sulphate (14 to 4240 mg/L) or nitrite (up to 47 mg/L). Transportation of the H2S strip tests between 10 and 32°C does not modify results significantly. Similarly to other studies: Klebsiella spp.; Enterobacter spp. and Serratia spp. were isolated from H2S strip tests. The mH2S strip test corresponds best with HPC in treated water, while in untreated river water it has approximately 90% correspondence with FCs, while survival of FC causes discrepancies with the H2S test after 22 days. A faecal coliform inactivation rate of 0.1 CFUs/ day, may be longer than many pathogens. Faecal source tracking, not currently practised in South Africa, could aid health risk assessments for disaster management, which would improve the NMMP programme. Bacterial survival times could propose the time period for which water is unsafe. Bifidobacteria and Rhodococcus are proposed to help identify the faecal pollution source. But enumeration of Rhodococcus is too lengthy (21 days). The tracking ratio of bifidobacteria (between 0.1 to 6.25) is not source definitive. The bifidobacteria survival rate, could indicator the time since faecal pollution. The bifidobacteria average survival rate is 2.3 CFUs per day for both groups. The culturability and selectivity of agar is still poor, with total bifidobacteria less selectively culturable. Enterococci overgrowth of TB was decreased by Beerens media. SUB is still useful to identify potential human faecal inputs. A single tracking method is thus not suitable alone, but requires a combination of techniques.

M.Sc. (Environmental Management) / Whether negative or positive, any human land use will have an impact on water quality. Point and non-point sources of contamination occur throughout the study area. Land use type and intensity will determine to what extent the water quality is affected. The aim of this research is to determine which human land use (within the study area) has the most prevalent effect on water quality. The Wilge River is a vitally important source of water for supply to the Gauteng region, and thus its quality is of a high priority, and yet little known or studied. Situated in the Grassland Biome of South Africa, on the Highveld in the Eastern Free State, the Upper Wilge River Catchment area is dominated by agricultural land use and has two human settlements that play an important role in the quality of water in the catchment. The Catchment is subdivided by four tributaries, which allow for smaller regions to be mapped out and studied individually. The various regions that have been mapped contain alternating types of land use including but not limited to cultivation and livestock agriculture; different types of human settlements. The Upper Wilge River also plays a role in the Tugela-Vaal Inter-Basin-Transfer (IBT) Scheme, and so water quality is also affected by this. South Africa is a water scarce country with highly erratic and unevenly distributed rainfall and thus the appointment of Catchment Management Agencies to monitor and manage water supply has been implemented by Government. By utilising Land use maps, Water Quality data and water quality guidelines, it is possible to identify spatial trends in water quality. There are nine specific water quality indicators that were selected according to the land use types present because various indicators may aid in identifying or representing specific human land use types, and thus highlight how different human land uses have different effects on water quality over a space. The respective water quality data for the nine specific indicators were acquired over the 12 sample points in the study area for a six year period. Data were transformed, analysed and simply visually represented in the form of bar and pie charts. Land use was mapped over the study area using Google Earth and a GIS (MapWindow). Finally data were interpreted in accordance with land use maps, water quality guidelines and thus water quality trends established. The main objective of this research was to identify, compare and determine which land use present has the most noticeable and detrimental effect on water quality. Essentially water quality depends on land use type and intensity within a catchment, but can also be affected by a variety of other anthropogenic or natural factors. Overall, the way in which the current human population utilises and impacts on the water quality is negative; but quality remains generally acceptable for the intended purpose of this water to downstream users, however this must be carefully monitored and managed, so as to ensure further degradation does not occur.