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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Pathogenic pollution of the Baynespruit.

Bararugurika, Zacharie. 22 May 2013 (has links)
The status of the Baynespruit bacteriological water quality is very alarming - E-coli concentrations have far exceeded the allowable limit of both local and international guidelines for more than a decade, namely 2000-2010. Concentrations of indicator bacteria have been recorded as high as 2419000 cfu/100 ml, whereas guideline levels of E-coli for recreational contact are about 130 cfu/100 ml. In this study, statistical analyses were carried out on data from two sampling points to clarify the seasonal changes and the variability of the pollution. Cross-correlation analyses showed that there was no significant correlation between E-coli concentrations and rainfall in the uMsunduzi catchment. There was also only a weak correlation between the two sampling points which suggests the existence of unregulated sources of pathogenic water pollution between the sampling locations that are independent of the effect that rainfall has on dilution and dispersion of pollution. The data indicates that the population living along the Baynespruit has about a 2% risk of contracting gastrointestinal illness as a result of the pollution in the stream. / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2011.
2

Illness, with particular focus on schistosomiasis, associated with recreational use of water by canoeists in the Msunduzi, Mngeni rivers in KwaZulu-Natal : issues and associated implications for other water users.

Oliver, Kirsten Lee. January 2006 (has links)
Water-related disease is a problem faced by many communities in the Mngeru and Msunduzi River valleys, both those living in a rural setting, and those within thedty bounds. Treatment and management of water-related diseases such as SchistosorrUasis and Hepatitis are, however, overshadowed by the priority management of more serious illnesses such as HIV/ AIDS, and are therefore at risk of spreading unchecked. These diseases, while not often fatal, have a high morbidity and place unnecessary burden on communities and individuals that could otherwise make a positive contribution to the social and economic structure of the country. The impacts of water-related disease are felt by all water-users, including those recreational users such as fishermen, swimmers and canoeists. Following a discussion of the issues and impacts of water-related disease at both a global and local scale, the research formulated a survey of the impact of water-related disease on canoeists training and racing on the Mngeni and Msunduzi Rivers as a starting point in determining the impacts on all communities using the resource. The methods employed were twofold, a Schistosoma haematobium infection- survey was conducted using urine samples; and a questionnaire-type survey of participants in the 2006 Dusi Canoe Marathon was conducted. The results of the Schistosomiasis survey revealed that 4.07% (20/491) of the respondents were positive in this survey. Analysis of the questionnaire filled in by all participants further revealed that 73% of respondents tested positive for Schistosomiasis infection at some point in their canoeing career. The post Dusi Marathon questionnaire survey was answered by 941 (54 %) participants. A total of 588 (63 %) reported experiencing illness as a result of taking part in the 2006 event. A further 362 individuals reported having experienced water-related illness on previous Dusi Marathons, indicating that 77% of the respondents have been ill on the Dusi in this and previous years' events. In addition, water quality samples were taken during the race and were shown to be significantly higher than the guidelines for safe recreational use of water resources. The results also showed a radical overnight change in the E.coli levels following a heavy rain event on the evening before the start of the race. The research revealed that there is a serious problem of water contamination and resultant spread of disease among canoeists using the rivers for recreational and professional sport. Contamination resulting from failure of sewage processing facilities during high rainfall events and industrial discharge into the river system results in excessive and unacceptable levels of E.coli and other water-related pathogens that are a severe health risk not only to canoeists but to all communities utilising this water resource. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2006.
3

Towards the development of a multi-criteria decision support system for selecting stormwater best management practices.

Duncan, Peter Neil. January 2001 (has links)
The aim of this dissertation was to develop a multi-criteria decision support system (MCDSS) to allow a specified manager to select with confidence one or many of these BMPs for a particular site. The principal design approach was a review of South African and international literature pertaining to stormwater management techniques, in particular BMPs. This information was formulated into a primary matrix using a rank-and-weighting method. The scores were then checked against the literature to ensure that they were reasonable, culminating in the initial MCDSS. The MCDSS was then provided with seven scenarios, described in the literature, and the output reviewed. Although, the MCDSS would select appropriately when given few criteria for selection when these were increased, inappropriate outcomes resulted. Consequently, weighting factors were assigned to each criterion. The MCDSS was further tested using all the selection criteria and the output deemed satisfactory. The MCDSS was then tested in a case study of the Town Bush stream catchment at eleven sites along the river network and the results were adequate. Taking into consideration the economic aspects of BMP implementation a need also arose for the sites to be allocated to certain authorities depending upon ownership or responsibility. The sites were prioritised depending on potential threat to property and lastly by the hydrological nature of the stream at each site. A stormwater plan for the study area was also proposed. Although the MCDSS was functioning adequately it was not without its limitations. Limitations included the use of drainage areas as a surrogate measure for peak discharge thus, not allowing the user to design a series of BMPs or treatment chain. A second limitation was that initially the BMPs were designed as offline systems where stormwater is managed before entering the channel but in this study they were used as inline systems. Hence the ultimate selection was biased towards those BMPs able to deal with large drainage areas. Recommendations for further improvement include the development of a surrogate measure for drainage area thus allowing the user to design a treatment chain of BMPs; testing the MCDSS in more diverse circumstances; developing a more comprehensive set of selection criteria; and developing a clearer priority-setting model as the one used was rather simplistic. In conclusion the MCDSS provides the user with a useful tool where the selection and implementation of BMPs no longer has to take place in an ad hoc manner. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2001
4

Non point source pollution with specific reference to the Mkabela Catchment.

Berry, S. R. January 2011 (has links)
Non point source pollution (NPS) has long been the negated form of pollution within our natural systems. With an increase in the demand for quality crops and staple foods, there have been added pressures on water systems to cope with increasing NPS pollution (NPS-P). The effect and importance of scale on the assessment of NPS pollution has been identified as a pivotal component in the assessment of such pollutants, in particular the translation of processes from a field to a catchment scale. It has therefore become important to further investigate and research the processes involved in transporting and retaining pollutants at each measurement scale. A number of models have been developed for simulation catchments, however none of the suitably address the issue of NPS pollution and the translation of processes from the field through to the catchment scale. Each model researched fails to effectively address processes over varying scales, and tend to concentrate on a particular scale of observation. There is a distinct lack of a capable mechanism that assesses NPS pollution across varying scales within a catchment. The Water Research Commission (WRC) NPS-P project aims at eventually developing a successful model that addresses the issue of assessing NPS pollution across a number of different scales. This study aimed at assessing the loads of sediments and nutrients at different scales and included the establishment of a research catchment in the Mkabela Catchment outside Wartburg in KwaZulu-Natal, and the collection and interpretation of rainfall, runoff and nitrate data for a full year of sampling. The sampling provided valuable data for the calculation of pollutant masses and concentrations within the Mkabela Catchment. Non Point Sources are generally more dilute with suspended solids and nitrate in particular tending to have a high transport dependence upon summer events with a high intensity and low duration. A varying degree of scales were monitored during this study, ranging from plot to catchment scale in order to assess the varying influences on NPS Pollution (Nitrate and Suspended Solids). Monitoring was conducted through research mechanisms ranging from runoff plots at the plot scale to catchment scale flumes. It was found that scale has a varying influence on NPS pollution, with pollutant concentrations measured to be at a maximum at the field scale, with a value of 13.54mg/l of nitrate measured within the cane fields from event 3. Suspended solid values taken from within the water samples were most apparent at the plot scale, within the runoff plots, with a maximum of 2866.7mg/l measured during event 3 as well. It was evident from measurements and results obtained for each of the 10 sampled events that the main influencing factor of the nitrate concentrations and suspended solid values was the nature of the event. Summer rainfall events (high intensity and short duration) provided large overland flow volume that contributed largely towards the high concentrations of both nitrate and suspended solids, whereas the winter rainfall event (low intensity and long duration) contributed little to the concentrations of nitrate and suspended solids. In contrast to nitrate concentration, the largest nitrate loads by mass were measured during event 1 at the large catchment scale (Bridge 2), with a total cumulative load of 74.17kg nitrate estimated to have been yielded at the catchment outlet. The majority of nitrate are yielded from the agricultural lands where farming practices lead to the application of chemicals preplanting and post emergence. Suspended solids displayed a similar trend to that of nitrate, with an increasing cumulative yield measured throughout the catchment, resulting in a total 13414kg of sediment being measured at Bridge 2. It is interesting that Event 1 measured the largest cumulative loads for both nitrate and suspended solids; however it was recorded as an average intensity event (19.1mm/h) in comparison to the largest sampled intensity event of 165.9mm/h (Event 4) during the study. This may be attributed to the fact that the event coincided with the planting schedule of the sugarcane crops, and so the bare nature of the agricultural fields resulted in increased overland flow, and hence nitrate and suspended solid transportation. Data collected during all the events clearly show that the impoundment (a farm dam) acts as a water quality filter by retaining many of the nitrate pollutants when they enter the dam as channel flow. In summary, the controlling processes governing NPS-P movement varied through the differing scales, with crop size, artificial chemical application, nature of the event and timing during the year all contributing in varying manners at the differing scales. Future research within the WRC-NPS-P project should continue with sampling from the designated research points and add several more seasons of data to the already comprehensive first season of sampling. In addition, once a reasonable number of seasons have been sampled and analysed within the Mkabela Catchment, the initiation and development of an effective, representative scaled NPS-P model that addresses the movement and retardation of pollutants is necessary to be able to successfully model and predict the movement of NPS-P through catchment systems. In particular the effects of the controls afforded by such features as road crossings, wetlands and farm dams should be taken into account in the modelling of sediment and nutrient movement from field to catchment scale. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2011.
5

Investigating non-regulatory barriers and incentives to stakeholder participation in reducing water pollution in Pietermaritzburg's Baynespruit.

Neysmith, Jocelyn. January 2008 (has links)
The Baynespruit, a stream running through the city of Pietermaritzburg in KwaZulu-Natal, is blighted by chronic, severe solid and liquid waste pollution in the form of sewage, industrial effluent and household garbage. It drains a large residential area, then flows through the city's main industrial area before reaching a low-income neighbourhood whose residents are unable to use the water for recreation and small-scale agricultural irrigation due to its polluted state. Both the Department of Water Affairs and Forestry (DWAF) and the local Msunduzi Municipality have been largely unsuccessful in their attempts to use regulatory means to address the situation over the past two decades. Bodies such as the Msunduzi Catchment Management Forum (MCMF) have little representation from industry and have been equally unable to initiate effective action. One possible way to work toward reducing pollution problems is to involve all stakeholders in a co-operative participatory process; a key element is therefore the use of incentives and the removal of barriers to participation. The aim of this research was to analyse past initiatives that have tried to address pollution in the Baynespruit, gain an understanding of stakeholders’ views of the problems and their relative importance, and identify economic, situational, developmental and socio-cultural barriers and incentives to participation in a multi-stakeholder process. To accomplish this, the research methodology included a number of different qualitative techniques as part of a case study approach. The main research tool used was a semi-structured interview conducted with individual stakeholders from government agencies and parastatals, industry, local residents and members of NGOs; the use of historical print media coverage and both participant and direct observation complemented the interview data. Though the details of past initiatives were difficult to trace due to the loss of institutional memory at both the agency and NGO level, they appear to have suffered from a lack of communication, accountability and inclusiveness among key stakeholders. Most of the stakeholders interviewed have an understanding of the various pollution problems affecting the Baynespruit and the consequent threat to human health, and there was general agreement that a mix of education, monitoring and enforcement was necessary to solve these problems. There was also broad support for a multi-stakeholder process, with all subjects stressing the need for action, not just discussion, as well as real engagement on the part of their fellow stakeholders. For local residents, building a network of contacts and partnerships could address many of the economic, developmental and socio-cultural barriers they face, and strengthen their effectiveness in fostering participation among other stakeholders. While barriers to industry participation in pollution reduction included problems such as a lack of consequences for polluting, and the feeling that it was ‘not their problem’, powerful economic and situational incentives, such as pressure from corporate customers and the public, remain largely unexploited. A lack of resources in the form of time, staff and equipment, as well as unsuccessful past experiences which have created a reluctance to prosecute or release information, were the major impediments preventing staff at regulatory agencies and parastatals from motivating other stakeholders to participate, though they were aware of the potential for increase effectiveness offered by participatory processes. It is hoped that by recommending ways to maximise incentives and reduce barriers, this research will assist the recently-established Baynespruit Conservancy, which is involving all interested parties in an effort to address the serious pollution problems in the stream. / Thesis (M.Env.Dev.)-University of KwaZulu-Natal, Pietermaritzburg, 2008.
6

Factors preventing the successful implementation of the polluter pays principle : a case study of the Bayne's Spruit.

Pole, Adrian Leonard. January 2002 (has links)
Despite the pollution control provisions provided in national and local legislation that explicitly or implicitly give effect to the polluter pays principle (PPP), certain rivers continue to suffer from persistent industrial pollution. This research focuses on one such river, the Bayne's Spruit, as a case study. The Bayne's Spruit is a small river that is located within an urban catchment, and which has been subjected to wet industrial pollution for over a decade. Much of this pollution is associated with the Pietermaritzburg edible oil industry. This pollution impacts negatively on a downstream community that uses the river for irrigation of subsistence crops, for recreation and for subsistence fish harvesting. The pollution has also severely degraded the riverine ecosystem. This research commenced with a literature review of the PPP in its international, national and local context. It was noted that the current legislative framework for implementation of the PPP with regard to pollution of rivers in South Africa comprises primarily of the National Water Act 36 of 1998 (NWA), the National Environmental Management Act 107 of 1998, and the Pietermaritzburg-Msunduzi industrial effluent bylaws of November 1998. The case study was approached using a largely qualitative methodology, although quantitative data was also relied upon where feasible. The historical context of the case study was provided by conducting a review of newspaper reports, a review of. government inspection records, and a review of water quality data (including biomonitoring and chemical data). The current status of the Bayne's Spruit was then explored by conducting in-depth historical interviews with community members, and by conducting direct observation of the environmental status of the Bayne's Spruit. This data was supplemented by an analysis of the test results of sampled industrial effluent, and by information obtained from representatives of two edible oil companies. In-depth, purposively selected interviews were conducted with various role players. (local government, regional government and industry) to identify what factors are preventing the successful implementation of the PPP in the case study area. Factors identified include a lack of environmental ethic within the edible oil industry, with some of these companies free riding on the Bayne's Spruit to maximize their profits. At a local level, factors preventing implementation of the PPP include deficiencies in the local industrial effluent bylaws, failures to administer and implement provisions contained in the bylaws, capacity restrictions and institutional paralysis. National legislation is not being successfully implemented because the government agency empowered under the NWA is deferring primary responsibility for dealing with pollution to the local authority. Factors also include difficulties associated with monitoring of rivers, including lack of capacity to engage in monitoring, and confusion over the functions of the various spheres of government. Finally, enforcement complexities are a major factor preventing successful implementation of the PPP. These problems relate to inadequate penalties, enforcement arrangements, capacity problems, separation of authority to operate the municipal sewer works and to enforce the industrial effluent bylaws, difficulties in identifying the offending polluter (causation), problems with access to company premises, the open access character of the storm water drainage system, previous failed prosecutions and reliance on the criminal justice system. / Thesis (M.Sc.)-University of Natal, 2002.
7

Impact of land use on water quality and aquatic ecosystem health of stream networks in the upper uMngeni catchment feeding Midmar Dam, KwaZulu-Natal, South Africa.

Van Deventer, Ross. January 2012 (has links)
Freshwater in adequate supply and quality is vital to life on Earth; however, land-based activities such as development, agriculture, mining and industry, and their associated contaminants, pose a major threat to the quality of freshwater water resources and health of aquatic ecosystems. The upper uMngeni catchment draining into Midmar Dam is a strategically significant water resource, supplying clean drinking water to the eThekwini, uMgungundlovu and Msunduzi municipalities. The quality of this resource is under threat from current land-based activities such as Mpophomeni settlement and agriculture and emerging threats in the form of the Khayalisha social housing project. Monitoring sites were established in varying land use types in three sub-catchments of the upper uMngeni, to assess water quality and ecosystem health impacts of current land uses on Midmar Dam. A suite of physical, chemical and biological water parameters were sampled in conjunction with SASS5 bio-monitoring to assess the associated impacts. Water quality and ecological condition were highest in forested land use and upstream of Mpophomeni where natural land cover and sparse settlement occurred. Marked declines in water quality and ecological condition were observed at areas under commercial agriculture, indicated predominantly by rises in nutrient concentrations and declines in the SASS5 indices. The most notable declines in water quality and ecological condition were observed at sites downstream of Mpophomeni settlement as a result of severe sewage contamination, indicated by high E. coli counts. Nutrient concentrations downstream of Mpophomeni settlement ranged from mesotrophic to hypertrophic, with nitrogen to phosphorus ratios indicative of nitrogen limitation. Ecological condition remained in the ‘seriously/critically modified’ category over the study period. Nutrient loads produced by Mpophomeni are the highest of all the land uses, followed by that of commercial agriculture; both should be viewed as a concern, more so when viewed in terms of their compound effect on Midmar Dam water quality. Current water quality draining the commissioned Khayalisha social housing development area is good and although not natural, is of no contamination concern to Midmar Dam. Results indicate that with current land use activities, urban development and agriculture pose a potential threat to the quality of Midmar Dam resource and that further development in the form of the Khayalisha social housing project may replicate impacts already prevailing in Mpophomeni, whereby a principle water resource may be threatened by eutrophication. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2012.

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