M.Ing. / Rietvlei Dam was completed in 1933, and has been utilized as a drinking water source for the City of Pretoria since then. The original process configuration operated for almost 50 years before being upgraded in 1988. This upgrading was mainly due to the eutrophication of the impoundment. The new plant worked excellently under normal conditions but certain serious problems did occur and full production could not be maintained at all times. Activated Carbon and Ozone are two possible solutions to these problems. This study was directed at investigating the possible implementation of Preozonation, Granular Activated Carbon, and Ozone and Granular Activated Carbon in combination (case study), and it was shown that: All these processes are beneficial to the final water quality. Pre-ozonation proved to be the most cost effective process, but the least effective process in improvement of the water quality. Ozone and Granular Activated Carbon in combination proved to be the least cost effective process, but should be the most effective in improvement of the water quality. Granular Activated Carbon proved to be the optimun process with regard to cost and water quality improvement. The final recommendation is the implementation of Granular Activated Carbon with an empty bed contact time of 10 minutes.

Submitted in fulfilment of the requirements of the degree of Master of Technology: Environmental Health, Durban University of Technology, 2014. / The study entailed the determination of key water quality parameters significantly influencing treatment cost in uMngeni Basin. Chemical dosage was used as a substitute for treatment cost as the study indicated that cost, in its monetary value, is influenced by market forces, demand and supply, which are both not directly linked to water quality. Chemical dosage is however, determined by the quality of water and thus provides a clear illustration of the effect of pollution on treatment cost. Three specific objectives were set in an effort to determine key water quality parameters influencing treatment costs in uMngeni Basin. The fourth objective was to develop a model for predicting chemical dosages. The first approach was analysis of temporal and spatial variability of water quality in relation to chemical dosage during production of potable water. The trends were explained in relation to river health status. For this purpose, time-series, box-plot, and the Seasonal-Kendal test were employed. The results showed that the quality of water significantly deteriorated from upstream to downstream in relation to algae, turbidity and Escherichia coli (E. coli). High mean range of E. coli (126-1319 colony count/100mL) and turbidity (2.7-38.7 NTU) observed indicate that the quality of water along the basin is not fit for human consumption as these parameters exceeded the target range stipulated in South Africa’s guidelines for domestic use. For water intended for drinking purpose, turbidity should be below 5 NTU, while zero E. coli count is expect in 100 mL. Among the six sampling stations considered along the uMngeni Basin, three dam outflows (Midmar, Nagle and Inanda) showed an improved quality compared with their respective inflow stations. This was expected and could be attributed to the retention and dilution effects. These natural processes help by providing a self-purification process, which ultimately reduces the treatment cost. While considering the importance of disseminating water quality information to the general public and non-technical stakeholders, the second objective of the study was to develop two water quality indices. These were; (1) Treatability Water Quality Index and (2) River Health Water Quality Index. The Treatability Water Quality Index was developed based on the Canadian Council Minister of Environment Water Quality Index (CCME-WQI). The technique is used to determine fitness of water against a set of assigned water quality resource objectives (guidelines). The calculated Harmonised Water Quality Resource Objectives (HWQRO) were used to compare the qualities of the raw water being abstracted at Nagle and Inanda Dam for the purpose of treatment. The results showed that Nagle Dam, which supplies Durban Heights, is significantly affected by E. coli (42% non-compliance), turbidity (20% non-compliance) and nitrate (18% non-compliance) levels. Wiggins Water Treatment Plant which abstracts from Inanda Dam has a problem of high algae (mean 4499 cell/mL), conductivity (mean 26.21 mS/m) and alkalinity (mean 62.66 mg/L) levels. The River Health Water Quality Index (RHWQI) was developed using the Weighted Geometric Mean (WQM) method. Eight parameters, namely, E. coli, dissolved oxygen, nitrate, ammonia, turbidity, alkalinity, electrical conductivity and pH were selected for indexing. Rating curves were drawn based on the target ranges as stipulated in South Africa’s guidelines for freshwater ecosystems. Five classes were used to describe the overall river health status. The results showed that the water is still acceptable for survival of freshwater animals. A comparison of the RHWQI scores (out of 100) depicted that dam inflow station (MDI(61.6), NDI(74.6) and IDI(63.8)) showed a relatively deteriorated quality as compared with their outflows (MDO(77.8), NDO(74.4) and IDO(80)). The third objective was to employ statistical analysis to determine key water quality parameters influencing chemical dosage at Durban Heights and Wiggins Water Treatment Plants. For each of the two treatment plants, treated water quality data-sets were analysed together with their respective raw water data-set. The rationale was to determine parameters showing concentration change due to treatment. The t-test was used to determine the significance of concentration change on each of the 23 parameters considered. Thereafter, the correlations between water quality parameters and the three chemicals used during treatment (polymer, chlorine and lime) were analysed. The results showed that the concentrations of physical parameters namely, algae, turbidity and total organic carbon at both treatment showed a significant statistical (p<0.05) reduction in concentration (R/Ro<0.95). This results implies that such parameters were key drivers for chemical dosage. From the results of the first three objectives, it is recommended that implementing measures to control physical parameter pollution sources, specifically sewage discharges and rainfall run-off from agricultural lands along the uMngeni Basin should assist in reducing the chemical dosage and ultimately cost. The fourth objective was to develop chemical dosage models for prediction purposes. This was achieved by employing a polynomial non-linear regression function on the XLStat 2014 program. The resultant models showed prediction power (R2) ranging from 0.18 (18%) up to 0.75 (75%). However, the study recommends a comparative study of the developed models with other modelling techniques.

This study investigates and compares the environmental burdens of two different methods for producing potable water by using the environmental life cycle assessment (LCA). The first method, for the production of potable water, is used by Umgeni Water at their Wiggins Waterworks and it involves conventional processes. The second method is based on a South African membrane technology and currently it is used in three pilot plants around the country. The life cycle concept gives the means understand the environmental impacts associated with a product. process or activity by considering all life-cycle stages, from cradle- to-grave. Formal methodologies for conducting such studies have been developed and in this project the methodological framework endorsed by the International Organisation for Standardisation (ISO) 14040 series of standards has been used. By using this methodology and by tracing all processes involved in the production of potable water, it was found that the main contribution towards the environmental burdens of potable water is due to electricity generation. This conclusion is valid for both methods in vestigated. and as a result the recommendations focus on increasing the energy efficiency of waterworks in order to increase their overall environmental performance. / Thesis (M.Sc.Eng.)-University of Natal, Durban, 2001.

M.Sc. (Environmental Management) / In South Africa, there are practically no freshwater lakes. Therefore, exploitable water supplies are confined to rivers, artificial lakes behind dams, and groundwater. The many demands for water, and the erratic flow of most South African rivers, have led to the creation of artificial lakes and dams, i.e. impoundments on all the major rivers, in order to stabilise flow and therefore guarantee annual water supply. Cyanobacterial bloom formation in freshwater sources, such as rivers, lakes, dams and reservoirs are known to occur throughout the world. In South Africa, the occurrence of cyanobacteria has also been recorded with the best known being the bloom of the hyper-eutrophic Hartbeespoort Dam. In South Africa specifically, cyanobacteria are mostly seasonally driven. Species that are known to cause bloom formation are Microcystis sp., Anabaena sp., Oscillatoria sp. and Cylindrospermopsis sp. These species are known to produce cyanotoxins that cause health problems in animals and humans, but also produce taste and odour problems in drinking water, if not treated effectively. In most cases where cyanobacteria blooms have been known to occur, it also enters source water for drinking water purification plants. Because source water containing cyanobacteria and the effect it has on the consumer, environment and animals, it is thus important to identify the dominant algae species. Cyanotoxin drinking water guidelines must be developed and implemented and a management plan for the Water Treatment Plant must be produced, to ensure that the risk of human exposure to the cyanotoxins are minimised. The present study focuses on the Vaalkop Dam from which raw water is abstracted and treated by the Magalies Water Vaalkop Water Treatment Plant (MWVWTP) to produce potable water. The source water abstracted from the Vaalkop Dam can contain high numbers of cyanobacteria as well as cyanotoxins that must be removed by the MWVWTP during potable water purification to ensure compliance to water quality standards. The overall objective of the study is to investigate the occurrence of cyanobacteria and cyanotoxins in the Vaalkop Dam at the point where the source water is abstracted for drinking water purification.

Thesis (MBA)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Providing basic access to water and sanitation is critical for poverty alleviation and stimulating economic growth, but at the same time it is putting a huge strain on South Africa’s existing economic infrastructure. Local governments allow their existing wastewater infrastructure to deteriorate to the extent that it no longer functions according to its design, and then apply for capital funding for refurbishment. Capital investment alone will not provide a sustainable solution to meet the increased demand on the ageing wastewater infrastructure, since local governments do not have the financial means and technical capacity to adequately maintain and operate their infrastructure. A paradigm shift is required to develop alternative and innovative business models to ensure a sustainable solution providing continued and consistent capacity as a basis for further expansion. Public-private partnerships (PPP) could provide a feasible solution towards building a sustainable technical capacity at local governments. Engaging the private sector must however not be aimed towards access to private sector finance, but rather the improvement in operational efficiency and increased level in service. Obtaining private sector finances will be the wrong focus for engaging in PPP undertakings in South Africa. Private operation must be combined with public financing. The design-build-operate (DBO) model with public financing would be highly viable. Such an arrangement will hold no financial risk to the private sector entity with revenue collection strictly remaining a local government function. The DBO method of delivery (with public funding) will be an effective way to realize cost savings, achieve efficiencies in construction and operation, utilize expertise, and most importantly, for skills transfers and capacity building at local government level. Ultimate sustainability will only be achieved once local government is able to raise the majority of its own funds for operation and maintenance through tariffs and other instruments, including some towards capital redemption. Grant funding must make provision for maintenance and operation of all capital funded projects. All shareholders must join forces in lobbying this concept at the highest political echelons because in terms of Section 154 of the Bill of Rights, national and provincial governments have a duty towards local governments to support and strengthen their capacity, to effectively perform their functions.

Submitted in fulfillment of the requirements for the degree of Master of Engineering, Department of Industrial Engineering, Durban University of Technology, Durban, South Africa, 2017. / Access to clean and adequate water is a universal and basic human right that feeds into the 6th of the 17 Sustainable Development Goals (SDGs). This goal aims at ensuring availability and sustainable management of water and sanitation for all. Clean water is referred to as potable water, which is safe for human consumption and offer low risk of immediate or long term harm. Raw water undergoes rigorous processing which consists of coagulation, sedimentation, filtration, disinfection and storage, to produce potable water. Each module or stage consumes chemicals and energy resources and thus incurs costs. To achieve the aim of the study, which was to synthesize an optimised potable water treatment network and a water usage analysis model, the Umzinto Water Treatment Plant (UWTP) and its distribution system was used as the study area. This treatment plant is located within Umdoni, a local municipality of the Ugu District Municipality in KwaZulu-Natal Province, South Africa. This study’s objectives were fourfold and the first objective was to identify and quantify key raw water quality parameters affecting treatment at the UWTP. The second objective was to design a genetic algorithm for the potable water treatment process control. The third objective was to evaluate the Umzinto Water Distribution System’s Non-Revenue Water (NRW) while the fourth objective was to develop a model for water usage analysis. For the first objective, data for water quality parameters for the water treatment from July 2006 to June 2013 were statistically analysed. This data were collected from the UWTP’s historical records. To improve the data’s integrity it was pre-processed using cubic hermite interpolation. After the pre-processing trend lines and box plots were used to determine the parameters’ significance compared to the standard values stipulated in the South African National Standard (SANS 241). The trend lines were used to analyse the frequency of observations that were higher than the standard values according to SANS 241. The box plots were used to determine the minimum, median, maximum and mean of the data sets. The mean values for each parameter were compared to the SANS 241 value to determine their significance. The raw water quality parameters were then correlated to the chemical dosages for lime, polymer, potassium permanganate and chlorine. The key parameters selected from the correlation analysis were algal count, manganese (Mn), iron (Fe), Escherichia coli, total coliforms, colour, odour, conductivity, turbidity, suspended solids (SS), pH, temperature, total organic carbon (TOC,) and Hardness. A number of methods can be used to achieve such optimisation, including artificial neural networks, dynamic programming, linear and non-linear programming, and this study utilised a genetic algorithm as an optimisation tool to achieve the second objective of optimising water treatment at the UWTP. For the model development, data from the correlations obtained for objective 1 were used. The model was aimed at reducing the cost of chemical dosage and four chemical dosage prediction models were developed using genetic algorithms and these were then used to produce a combined chemical dosage cost prediction model. The programming interface utilised for these models was Matlab. In developing these models, the data were first pre-processed to remove outliers and fill in the blanks using a Microsoft Excel Add-in that was developed for this particular purpose. The next step involved a curve fitting exercise in Microsoft Excel 2013. Matlab was then used to code the genetic algorithm that combined and optimised the solutions obtained from the curve fittings. The results showed that genetic algorithms can be reliably used to predict the chemical dosages and hence reduce water treatment costs. After treatment, water is pumped into the distribution system for consumption. It is therefore important to ensure that all the pumped out treated water reaches the consumer. The third objective therefore assessed the NRW for the Umzinto Water Distribution System for the period between July 2013 and June 2014. The data used for this objective was provided by the Ugu District Municipality. The method used combined the top-down approach and the component-based approach. This combined approach was modified to enable the calculation of all the components that are required in a standard South African Water Balance. The results showed that the distribution system had a high value of NRW, which was 27.9% of the System Input Volume. The major component of NRW was Real Losses, that is, losses that can be mitigated by improving maintenance. The fourth objective was to develop a model for water usage analysis that would reduce the time taken to evaluate NRW and also improve the analysis of the NRW components using Microsoft Visual Basics 2012 and Microsoft SQL Server 2012 development interfaces. The Visual Basics enabled the development of a graphic user interface that was user-friendly and minimised the time taken to learn the software. The software platform developed was able to import the data required to construct a standard International Water Asssociation (IWA) Water Balance, calculate all the components of NRW, store historical data for the water distribution systems and report on a rolling year basis. A model for water usage analysis was developed and made available for usage by practitioners in Ugu District. The model was developed for the specific study area and further studies would be required in order to validate it in a different setting. The results obtained for the first objective led to the conclusion that, there was very high pollution emanating from communities and activities close to the raw water sources, especially the EJ Smith Dam. The results from the first objective were also used to determine parameters for the models developed in the second objective. From objective two it was concluded that genetic algorithms can be reliably used to predict chemical dosages and hence reduce water treatment costs. The third objective’s results showed that 27.9% of treated water pumped into the distribution system is NRW. Which is a concern because 65% of this are real losses which have maintenance related problems. The fourth objective’s results showed the practicality of designing model that could be used determine all the important components of NRW that would take time to evaluate manually. It would also store historical data for the water distribution system and report on a rolling year basis. Implementation of this software would help minimise the errors associated with manual calculation of NRW and improve the availability of data for research and analysis. From the research findings, it is recommended that the treatment plant should change the way it is dosing chemicals in the balancing tank. The method currently being used is prone to error. The analysis of NRW showed that Real Losses were a major challenge in the Umzinto Distribution System. There is need to develop a maintenance program to cater for leakage. Communities also need to be educated on the importance of reporting leakage in the network. / M

Thesis (MPA)--Stellenbosch University, 2014. / The asset management process and strategy has been adopted and implemented within the public sector. Although the National Treasury developed the Capital Asset Management Guidelines to assist with the development and implementation of the asset management system the guidelines have received very little attention over the years. The Auditor General’s findings indicate a lack of proper implementation of the asset management process. The study provides a clear indication of the implementation of the asset management process by most government entities, local government municipalities and the public sector. The outcome is that while most entities have made progress with regards to the implementation, much remains to be done. Most entities implement the asset management process selectively. This does not yield positive and sustainable results and they end up abandoning the whole asset management system. The report provides the process of successful development and implementation of asset management, it also indicate that if there are element that are missed or not properly done the process will not yield constant results or performance and the impact on the organization performance will not be positive. The management of the organization must ensure that asset management is aligned with strategic objectives of the organization and performance measurement must be directly linked with asset management, performance measurement should be used to determine progress and implementation. Service level agreements must be established between all relevant departments including the finance department and there must be agreement on the objectives between all stakeholders. The key to proper implementation is the alignment of the asset management process with the strategic objectives of the organization.

Submitted in complete fulfillment for the degree of Doctor of Philosophy (Biotechnology), Durban University of Technology, Durban, South Africa, 2016. / Seasonal nitrification breakdown is a major problem in wastewater treatment plants which makes it difficult for the plant operators to meet discharge limits. The present study focused on understanding the seasonal impact of environmental and operational parameters on nitrifiers and nitrification, in a biological nutrient removal wastewater treatment works situated in the midlands of KwaZulu Natal. Composite sludge samples (from the aeration tank), influent and effluent water samples were collected twice a month for 237 days. A combination of fluorescent in-situ hybridization, polymerase chain reaction (PCR)-clone library, quantitative polymerase chain reaction (qPCR) were employed for characterizing and quantifying the dominant nitrifiers in the plant. In order to have more insight into the activated sludge community structure, pyrosequencing was used in profiling the amoA locus of ammonia oxidizing bacteria (AOB) community whilst Illumina sequencing was used in characterising the plant’s total bacterial community. The nonlinear effect of operating parameters and environmental conditions on nitrification was also investigated using an adaptive neuro-fuzzy inference system (ANFIS), Pearson’s correlation coefficient and quadratic models. The plant operated with higher MLSS of 6157±783 mg/L during the first phase (winter) whilst it was 4728±1282 mg/L in summer. The temperature recorded in the aeration tanks ranged from 14.2oC to 25.1oC during the period. The average ammonia removal during winter was 60.0±18% whereas it was 83±13% during summer and this was found to correlate with temperature (r = 0.7671; P = 0.0008). A significant correlation was also found between the AOB (amoA gene) copy numbers and temperature in the reactors (α= 0.05; P=0.05), with the lowest AOB abundance recorded during winter. Sanger sequencing analysis indicated that the dominant nitrifiers were Nitrosomonas spp. Nitrobacter spp. and Nitrospira spp. Pyrosequencing revealed significant differences in the AOB population which was 6 times higher during summer compared to winter. The AOB sequences related to uncultured bacterium and uncultured AOB also showed an increase of 133% and 360% respectively when the season changed from winter to summer. This study suggests that vast population of novel, ecologically significant AOB species, which remain unexploited, still inhabit the complex activated sludge communities. Based on ANFIS model, AOB increased during summer season, when temperature was 1.4-fold higher than winter (r 0.517, p 0.048), and HRT decreased by 31% as a result of rainfall (r - 0.741, p 0.002). Food: microorganism ratio (F/M) and HRT formed the optimal combination of two inputs affecting the plant’s specific nitrification (qN), and their quadratic equation showed r2-value of 0.50. This study has significantly contributed towards understanding the complex relationship between the microbial population dynamics, wastewater composition and nitrification performance in a full-scale treatment plant situated in the subtropical region. This is the first study applying ANFIS technique to describe the nitrification performance at a full-scale WWTP, subjected to dynamic operational parameters. The study also demonstrated the successful application of ANFIS for determining and ranking the impact of various operating parameters on plant’s nitrification performance, which could not be achieved by the conventional spearman correlation due to the non-linearity of the interactions during wastewater treatment. Moreover, this study also represents the first-time amoA gene targeted pyrosequencing of AOB in a full-scale activated sludge is being done. / D

M.Tech. (Architectural Technology) / This project is an architectural response to a setting shared by an active open cast platinum mine and the surrounding rural traditional subsistence farming communities located in the Mogalakwena municipality, Limpopo Province. The area is characterised by its mine waste landscape and large open cast pits, all of which are remnants of the process of open cast mining. The Mogalakwena communities’ economic livelihood is largely dependent on agricultural land. This land is reducing, partly due to the establishment and expansion of the mine and partly to the increased growth rate of the surrounding communities. This project argues that the remnants of the mining industry (particularly open cast pits, mine waste rock and infrastructure) need not be redundant and can be reused and rehabilitated to result in productive outcomes by establishing the necessary systemic strategy for transposed use. It contends that the proposed reconfi gured mining infrastructure programs can be responsive to context (history, environment and communities), climate and natural processes of the area. In testing the strength of this argument, diff erent research investigations and theories were used as was appropriate to each area of research in this topic. These included, among others, investigations into the history and context of both the mining industry generally, including its legislative context, and the site specifi cally. Considerations of the embedded memory of the site were taken into account. Theories which assisted in leading to a proposed strategy for the site on a contextual scale included theories relating to contextual productive systems, continuous productive urban landscapes, permaculture and biomimicry, augmented landscapes, entropic architecture, architecture as a machine and the mortality of architecture. Ultimately, a proposed solution as an architectural product was sought. The following questions had to be answered in a eff orts to produce an appropriate architectural response to the site and its challenges: 1. How can the role of architecture reconfigure the redundant, disused mine waste landscape so as to harness a rehabilitative and productive system and how can that system be managed by the design? 2. How can contemporary rural agricultural projects be challenged to form new typologies that empower the communities to provide for their own present and future needs? 3. How can architecture as a system be designed to outlast the temporality of its program to transform a redundant open cast mining landscape into a productive landscape? The architectural intervention is a design of reconfi gured structures aimed at facilitating a productive and sustainable environment for agricultural advancement, in order to rehabilitate the existing “minescape” (industrially altered mining land), and reconcile the use of this land with the history of subsistence farming as practiced by members of the surrounding communities. The proposed architectural product strives to create a site and context responsive architectural program or system by fusing technological strategies into the body of architecture that are essentially environmental. It aims to employ air, water, sun, and earth to augment the productive relationship between architecture and the “minescaped” terrain, thereby creating a Productive Minescape, which yields tangible positive by-products such as agriculture, renewable energy, water treatment and harvesting systems, among others. Other productive by-products of the project are education and research facilities and facilities which aim to provide accessibility and reconciliation of the stakeholders of this area, to the site and to each other. The introduction of these systems and facilities will be phase one of the proposed architectural intervention. However, the intervention is networked, and therefore has a scalable logic which is envisaged to grow and develop at a much larger and more intensive scale, suggested to occur over the next 30 years, which are phases two, three and four (see figures 17 and 18).

South Africa is a water scarce country. The expansion of the industrial, mining, and agricultural sectors to meet the needs of South Africa’s growing population requires more water. There is therefore an urgent need to develop effective wastewater treatment processes in order to recover and reuse water. This dissertation presents the treatment of an acidic wastewater stream from a platinum refinery which at present is being disposed of by contract with a waste disposal company. The major concern in treating the acid effluent stream is the high concentration of sodium ions (18 200 mg/l) and chloride ions (104 900 mg/l). The precipitation process is used to treat wastewater, but ultimately it generates more secondary waste as a sludge. The other process that is used to treat wastewater is reverse osmosis (RO). RO is usually preferred in the last stage of the treatment because the process is more expensive as membranes need to be replaced regularly. The approach used in this research focuses on evaporating liquid, consequently concentrating the remaining solution until the ions in the solution crystallize. The liquid produced is recycled back into the platinum plant for reuse, and the remaining salt crystals are collected as the useful product. The proposed water treatment process produces dilute hydrochloric acid as the condensate and a crystallized sodium chloride rich residue. The refinery is currently disposing of around 20 000 l/day of wastewater to landfills. The proposed treatment process can recover half of the volume of the wastewater stream to the refinery, helping reduce the fresh water consumption of the process by 10 000 l/day. Furthermore, this will reduce the volume of wastewater going to disposal by a half, namely only 10 000 l/day will need to be disposed of. The amount of Cl that can be recovered is variable and depends on the quantity of chloride in the wastewater. In the two samples processed the recovery was between a 2,5 w% and 10,7 wt% aqueous HCl solution. This corresponds to a saving of between 250 to 1000 kg/day of HCl. As the concentration of the recovered solution is variable, the recycling process would need to monitor the composition of the recycled stream and make up the acid concentration to some fixed value for reuse in the prices. The production of a dilute hydrochloric acid stream should be particularly attractive to the platinum refinery as the operation of the refinery requires hydrochloric acid as a feed. Thus, by recycling the wastewater, the refinery would reduce the volume of wastewater to be disposed of thereby reducing the cost of disposal of the waste while simultaneously reducing the cost of buying fresh hydrochloric acid. The proposed recovery of liquid and recycling it back to the refinery, will also reduce the environmental impact of the refinery, and very importantly in a water scarce country, reduce the freshwater consumption of the process. / Physics / M. Sc. (Physics)