Sector Wide Approach (SWAP) can be defined as collaboration between governments, development partners and civil society. It promotes coordination of various donor funded programmes to align with a common sector vision. In the case of South Africa, a water sector SWAP was introduced in 2000. Funds were directed to municipalities that were providing water known as Water Services Authorities (WSAs). This study examines the impact of the SWAP on tangible water delivery issues in Ukhahlamba District Municipality, Eastern Cape. The literature reviewed focuses on rural development in South Africa, and abroad. The quantitative aspect of the research considered various sources including primary data from municipal records of water services provision. Interviews were held with community members, municipal and provincial government officials. Analysis of information from these sources indicates some aspects of water delivery were positive and some negative. Recommendations for improvement and further research are made in the last chapter. / Development Studies / M.A. (Development Studies)

The study assessed the effectiveness of environmental management structures and participation process in the upper Pungwe River basin. It looked at the interaction of environment and water management institutions and stakeholder structures in environmental management. A concurrent mixed methods approach was used. Qualitative and quantitative data collection and analysis techniques were employed. Seventeen questionnaires were administered to environmental management committee chairpersons. Interviews were held with three water resources management experts from the ZINWA and PSCC. Another three questionnaires were administered to the EMA, Mutasa RDC and Mutasa District Administrator. Water quality, sediment load and river runoff data for the Pungwe River was analysed using Mann-Kendal and Regression Analysis Statistics to detect trends and predict future levels. River sediment load showed a negative linear relationship with pH levels. Stakeholder participation still require enhancement. Coordination of land/environment and water management institutions and local stakeholders remains the key to achieving sustainable environmental management. / Environmental Sciences / M. Sc. (Environmental Management)

Thesis submitted in fulfilment of the requirements for the degree Doctor of Technology: Biomedical Technology in the Faculty of Health and Wellness Sciences at the Cape Peninsula University of Technology 2008 / The quality of South Africa’s water sources is fast deteriorating due to an influx of pollutants from industrial and agricultural areas. In addition, urbanisation has led to the establishment of informal settlements along river systems. This study focuses on the importance of maintaining water quality and the management of water resources in order to ensure its sustainability in South Africa. The primary aim of this study was to determine the extent of bacterial contamination in three rivers namely the Berg-, Plankenburg- and Diep Rivers in the Western Cape, South Africa and to investigate the application of a bioremediation system as a possible treatment technology. Several aspects contributing to the contamination were addressed and different approaches were studied and reviewed. In all three rivers, four sampling sites were identified, which were sampled over a period of 9 to 12 months. Contamination levels for the three rivers were evaluated by applying various enumeration techniques, which could provide an accurate indication of the planktonic bacterial pollution load in the river systems. The Most Probable Number (MPN) technique was used to determine the level of faecal coliforms and E. coli. The highest MPN, faecal coliform and E. coli counts of 3.5 x 107 micro-organisms/100 m , 3.5 x 107 micro-organisms/100 m and 1.7 x 107 micro-organisms/100 m , respectively, were recorded at Site B2 in week 37 in the Berg River. Results showed that in all the river water sampled and evaluated, the total MPN count mostly exceeded the maximum limit of 2000 micro-organisms/100 m (SABS, 1984) stipulated for river water throughout the study period. The heterotrophic plate count (HPC) method was used to determine the number of culturable micro-organisms in planktonic samples, while the flow cytometry (FCM) and epifluorescence microscopy (EM) with different fluorochromes (Acridine orange and BacLight™ Live/Dead stain) were employed to evaluate total bacterial counts in planktonic (water) samples. The highest HPC at the various sites sampled was 1.04 x 106 micro-organisms/m (Berg River, Site B2), 7.9 x 104 micro-organisms/m (Plankenbrug River, Site A) and 1.7 x 105 micro-organisms/m (Diep River, Site B). Total cell counts as high as 3.7 x 107 micro-organism/m (Berg River, Site B2), 5.5 x 108 micro-organism/m (Plankenburg River, Site D) and 2.5 x 109 micro-organisms/m (Diep River, Site B) were obtained by the FCM technique, which were significantly (p < 0.05) higher than the total counts obtained by epifluorescence microscopy. The results thus show that the FCM technique was the most reliable method for determining the total cell count in river water samples. This technique makes use of computer software whereas epifluorescence microscopy involves manual counting which may lead to human error. In addition, the impact of residential, agricultural and industrial areas situated along these rivers was also investigated. Even though exact point sources of pollution could not be determined, it was found that all the sources, such as the storm water drainage pipes, the industrial as well as the agricultural areas, could contribute to increased MPN, heterotrophic and total bacterial counts. This study also aimed at investigating and comparing the microbial contamination levels at various sites in the Plankenburg and Diep Rivers in the Western Cape, South Africa. Sampling of sites along the Plankenburg River started in June 2004 and continued for a period of one year until June 2005. Sampling of the Diep River sites started in March 2005 and continued for a period of nine months until November 2005. Faecal coliform (FC) and E. coli (EC) counts were determined by means of the Most Probable Number technique, the number of culturable cells were determined using the heterotrophic plate count (HPC) technique and total microbial counts were evaluated by Flow cytometric analysis (FCM). The highest microbial counts for the Plankenburg River were observed at site B where the highest MPN, FC, E. coli and total FCM counts of 9.2 x 106 (week 14), 3.5 x 106 (week 39) and 3.5 x 106 micro-organisms/100 m (week 39) and 2.1 x 108 micro-organisms/m (weeks 1 and 39) respectively, were recorded. The highest HPC recorded for the Plankenburg River was 7.9 x 106 micro-organisms/100 m (week 44, site A). Site B is situated close to an informal settlement where waste effluents from storm water drainage pipes enter the river system. In addition, other possible contamination sources included agricultural (site A) and industrial (site C) areas bordering the Plankenburg River. The highest total MPN, FC and E. coli counts in the Diep River were 5.4 x 106 (week 23) and 1.6 x 106 micro-organisms/100 m [FC and E. coli, respectively (both in week 23)], recorded at site B. The highest HPC and total FCM counts of 1.7 x 107 micro-organisms/100 m (week 14) and 2.5 x 109 microorganisms/ m (week 23), respectively, were also recorded at site B. This site was identified as the most contaminated site along the Diep River and served as an accumulation point for waste effluents from the residential and industrial areas, which included paint and machine manufacturers. Other sources situated along the Diep River included storage and maintenance facilities for steel containers, a waste water treatment plant and an oil-refinery. Most of the bacterial counts obtained for the Plankenburg and Diep Rivers exceeded the accepted maximum limit for river water for most of the sampling period. Bacterial species from the Berg- and Plankenburg Rivers were isolated and identified. The presence of various Enterobacteriaceae species isolated at all the sites in both rivers confirmed faecal contamination of these water sources over the entire sampling period. Opportunistic pathogens such as Klebsiella sp., Serratia sp., Enterobacter sp., Shewanella sp., Aeromonas sp., Pseudomonas sp., Acinetobacter sp. and Citrobacter freundii as well as pathogens such as Bacillus cereus and B. anthracis were also identified in both river systems. All the respective articles are presented in the required format of the journal in which the article has been published or submitted to.

Thesis submitted in fulfilment of the requirements for the degree Doctor of Technology: Biomedical Technology in the Faculty of Health and Wellness Sciences at the Cape Peninsula University of Technology 2008 / River systems can become contaminated with micro-organisms and metals and the routine monitoring of these rivers is essential to control the occurrence of these contaminants in water bodies. This study was aimed at investigating the metal contamination levels in the Berg-, Plankenburg- and Diep Rivers in the Western Cape, South Africa, followed by the remediation of these rivers, using bioreactor systems. Sampling sites were identified and samples [water, sediment and biofilm (leaves, rocks and glass, etc.)] were collected along the Berg- and Plankenburg Rivers from May 2004 to May 2005 and for the Diep River, from February 2005 to November 2005. The concentrations of aluminium (Al), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), lead (Pb) and zinc (Zn) were determined using the nitric acid digestion method and analysed by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES). For the Berg River, the highest concentrations in water samples were recorded for Al, Mn and Fe at the agricultural area (Site A – chapter 2). In the sediment and biofilm samples, the highest metal concentrations were once again recorded for Al and Fe. The concentrations of Al and Fe were significantly higher (p < 0.05) than than Cu, Zn, Pb, Ni and Mn in water, sediment and biofilm samples, and were mostly higher than the quality guidelines recommended by the Department of Water Affairs and Forestry (DWAF, 1996) and the Canadian Council for the Ministers of the Environment (CCME, 2001). Possible sources of contamination in the Berg River could be due to the leaching or improper discarding of household waste from the informal- and established residential areas, as well as the improper discarding of pesticides at the agricultural area. For both the Plankenburg and Diep Rivers the Al and Fe concentrations were higher than all the other metals analysed for in sediment and water samples. The highest concentrations recorded in the Plankenburg River was 13.6 mg.l-1 (water - Week 18, Site B) and 15 018 mg.kg-1 (sediment - Week 1, Site C) for Al and 48 mg.l-1 (water - Week 43, Site A) and 14 363.8 mg.kg-1 (sediment - Week 1, Site A) for Fe. The highest concentrations recorded in the Diep River was 4 mg.l-1 (water - Week 1, Site A) and 19 179 mg.kg-1 (sediment - Week 1, Site C) for Al and 513 mg.l-1 (water - Week 27, Site A) and 106 379.5 mg.kg-1 (sediment - Week 9, Site C) for Fe. For most of the metals analysed the concentrations were higher than the recommended water quality guidelines as stipulated by the Department of Water Affairs and Forestry (DWAF, 1996b), the Canadian Council for the Ministers of the Environment (CCME, 2001) and the ‘World average’ (Martin and Windom, 1991). Point sources of pollution could not conclusively be identified, but the industrial and residential areas could have influenced the increased concentrations. Metal concentrations should be routinely monitored and the guidelines should be updated and revised based on the current state of the rivers and pollution influences. Micro-organisms isolated from flow cells after exposure to varying metal concentrations were investigated for possible metal-tolerance. A site where high metal concentrations were recorded along the Plankenburg River was investigated. The micro-organisms isolated from the flow cells were cultured and identified using the Polymerase Chain Reaction (PCR) technique, in conjunction with universal 16SrRNA primers. The phylogeny of the representative organisms in GenBank, were analysed using the Neighbour-joining algorithm in Clustal X. After exposure, the channels were stained with the LIVE/DEAD BacLightTM viability probe and visualised using Epifluorescence Microscopy. The results revealed that when exposed to the highest concentrations of Al (900 mg.l-1), Fe (1000 mg.l-1), Cu (10 mg.l-1) and Mn (80 mg.l-1), the percentage of dead cells increased, and when exposed to the lowest concentrations of Al (10 mg.l-1), Cu (0.5 mg.l-1), Mn (1.5 mg.l-1) and Zn (0.5 mg.l-1), no significant differences could be distinguished between live an dead cells. When exposed to the highest concentrations of Zn (40 mg.l-1) and Ni (20 mg.l-1), no significant differences between the live and dead cell percentages, were observed. The phylogenetic tree showed that a diverse group of organisms were isolated from the flow cells and that some of the isolates exhibited multiple metal resistance (Stenotrophomonas maltophilia strain 776, Bacillus sp. ZH6, Staphylococcus sp. MOLA:313, Pseudomonas sp. and Delftia tsuruhatensis strain A90 exhibited tolerance to Zn, Ni, Cu, Al, Fe), while other isolates were resistant to specific metals (Comamonas testosteroni WDL7, Microbacterium sp. PAO-12 and Sphingomonas sp. 8b-1 exhibited tolerance to Cu, Ni and Zn, respectively, while Kocuria kristinae strain 6J-5b and Micrococcus sp. TPR14 exhibited tolerance to Mn). The efficiency of two laboratory-scale and one on-site bioreactor system was evaluated to determine their ability to reduce metal concentrations in river water samples. The laboratory-scale bioreactors were run for a two-week and a three-week period and the on-site bioreactor for a period of ten weeks. Water (all three bioreactors) and bioballs (bioreactor two and on-site bioreactor) were collected, digested with 55% nitric acid and analysed using ICP-AES. The final concentrations for Al, Ni and Zn (bioreactor one) and Mn (bioreactor two), decreased to below their recommended concentrations in water samples. In the on-site, six-tank bioreactor system, the concentrations for Fe, Cu, Mn and Ni decreased, but still exceeded the recommended concentrations. The concentrations recorded in the biofilm suspensions removed from the bioballs collected from bioreactor two and the on-site bioreactor, revealed concentrations higher than those recorded in the corresponding water samples for all the metals analysed, except Fe. The bioballs were shown to be efficient for biofilm attachment and subsequent metal accumulation. The species diversity of the organisms isolated from the bioreactor (bioreactor two) experiment after three days (initial) differed from the organisms isolated after 15 days (final). Hydrogenophaga sp., Ochrobactrum sp, Corynebacterium sp., Chelatobater sp. and Brevundimonas sp. were present only at the start of the bioreactor experiment. The surviving populations present both in the beginning and at the end of the bioreactor experiment belonged predominantly to the genera, Pseudomonas and Bacillus. Metal-tolerant organisms, such as Bacillus, Pseudomonas, Micrococcus and Stenotrophomonas, amongst others, could possibly be utilised to increase the efficiency of the bioreactors. The bioreactor system should however, be optimised further to improve its efficacy.

CAPES / Os corpos hídricos têm suas características afetadas pela poluição difusa, por meio do carreamento de poluentes pelo escoamento superficial nos eventos de chuvas ou também por despejos pontuais. Esta pesquisa foi realizada nas cavas do Parque das Águas em Pinhais/PR e teve por objetivo avaliar a qualidade das águas e sedimentos dos corpos hídricos e a sua correlação com a poluição difusa. Foram analisadas algumas variáveis físico-químicas, bacteriológicas e de compostos orgânicos HPAs e n-Alcanos em 6 pontos, que podem indicar possíveis alterações na qualidade desses corpos hídricos. Estas cavas deverão futuramente ser destinadas para uso de recreação de contato secundário, como pesca e esportes náuticos pela LEI No 189/87 - Pinhais, indicando que as águas dessas cavas devem atender a resolução CONAMA 357/05, que estabelece limites para parâmetros físico- químicos, biológicos e de espécies metálicas que possam causar danos à saúde e ao ambiente. Para embasar a discussão dos resultados para HPAs e espécies metálicas em sedimento, utilizou-se a resolução CONAMA 344/04. Os limites indicados pelas resoluções do CONAMA 357/05 e 344/04, são valores de segurança. Com base nos resultados obtidos, identificou-se a influência das chuvas nas concentrações das variáveis analisadas. Através da comparação dos resultados com a Resolução CONAMA 357/05 para água doce de classe 2, pôde ser constatado que os parâmetros salinidade, OD, turbidez, amônia, nitrito, nitrato estão de acordo com os limites impostos pela resolução, a DBO a para maioria dos pontos analisados apresentou-se dentro dos limites, porém em um dos pontos excedeu o limite. Para Coliformes termotolerantes, a maior parte dos pontos se apresentou dentro dos limites estabelecidos pela resolução. A variável Sulfeto não atende a CONAMA 357/05. Dos sete metais analisados em água cádmio e ferro apresentam-se acima do limite para o CONAMA 357/05. Os metais cobre, zinco, cádmio, níquel e chumbo em sedimentos estão dentro do limite da resolução CONAMA 344/04, mas em alguns pontos amostrados os HPAs indicaram contaminação por elementos de origem petrogênica quando confrontados com os limites indicados nesta mesma resolução. Para evitar que os limites sejam excedidos, visto que alguns dos pontos amostrados estão muito próximos, ou extrapolando os limites indicados, faz-se necessário evitar a entrada de poluente nas cavas do parque em questão, devido ao grande risco de perder a qualidade destes corpos hídricos e prejudicar a sua função para a sociedade. A pesquisa permitiu identificar que o incremento da carga poluente é potencializado pelo escoamento superficial das chuvas, inferindo desta forma, a necessidade do controle da poluição difusa para a área do parque. Uma das possíveis soluções seria a implantação de sistemas de wetlands construídos, que podem funcionar como barreiras para a entrada de poluentes, principalmente nas cavas mais próximas às estruturas viárias pavimentadas. / The water bodies have the characteristics affected by diffuse pollution through the drift of pollutants in the runoff from rain events or also by occasional evictions. This research was conducted in pools of the Water Park in Pinhais/PR and aimed to assess the quality of waters and sediments of water bodies and their correlation with diffuse pollution. The analyses from some physico-chemical, bacteriological and organic compounds PAHs and n-alkanes in 6 points, indicated possible changes in the quality of these water bodies. These pools will be designed for future use of secondary contact recreation such as fishing and water sports in the LAW 189/87 - Pinhais-PR, indicating that the water pools must answer these CONAMA Resolution 357/05, which sets limits for physical- chemical, biological and metal species that may cause damage to health and the environment. To support the discussion of the results for PAHs in sediment and metal species, is used the CONAMA Resolution 344/04. The limits given by CONAMA resolutions 357/05 and 344/04, are safety values. Based on these results, we identified the influence of rainfall in the concentrations of all variables. By comparing the results with CONAMA Resolution 357/05 for freshwater class 2, it might be noted that the parameters salinity, dissolved oxygen, turbidity, ammonia, nitrite, nitrate comply with the limits imposed by resolution, for the DBO Most points analyzed was within the limits, but in one of the exceeded limit. For Fecal coliform, most points are presented within the limits established by resolution. The variable sulfide does not meet CONAMA 357/05. Of the seven metals analyzed in water cadmium and iron are found above the ceiling for CONAMA 357/05. The metals copper, zinc, cadmium, nickel and lead in sediments are within the limit of CONAMA Resolution 344/04, but in some sampling sites indicated PAH contamination source elements petrogenic when confronted with the limits specified in this same resolution. To avoid the exceeding the limits, since some of the points are very close, or extrapolating the limits, it is necessary prevent the entry of polluting the pools of the park in question, due to the high risk of losing the quality of these bodies water and impair its function for society. The research identified that the increase in pollution load is powered by the runoff of rainfall, implying thus the need for control of diffuse pollution to the park area. One of the possible solutions would be the deployment of constructed wetlands, which can act as barriers to the entry of pollutants, mainly pools nearest paved road structures.

CAPES / O ciclo hidrológico sustenta a falsa ideia de que a água é um recurso natural ilimitado e por esse motivo a questão foi negligenciada por muito tempo. Atualmente, entretanto, a preocupação com a água no planeta já ultrapassou os limites de países que sofrem de escassez. Isso resulta em uma busca constante por programas de conservação da água e pelo uso de fontes alternativas para consumo humano, dentre elas o aproveitamento de água da chuva. O presente trabalho tem por objetivo principal a verificação do impacto do aproveitamento de água da chuva em residências unifamiliares no consumo de água potável e na drenagem urbana. Através do estudo de caso de um condomínio horizontal na cidade de Curitiba, Paraná, fez-se uma avaliação quantitativa do volume de chuva aproveitado e extravasado no sistema de aproveitamento, através de do is métodos de dimensionamento do volume do reservatório: Método Prático Alemão (ABNT 15.527/2007) e Método do Decreto 293/2006 de Curitiba. Além disso, utilizando dados pluviométricos diários, desde 1997 até 2013, três cenários de demanda de água de chuva foram criados, dos quais é possível verificar a eficiência e a confiança dos sistemas adotados, a fim de determinar quanto da demanda é atendida e quanta água fica retida nos reservatórios. / The false idea that water is an unlimited natural resource is supported by the water cycle, and therefore the issue has been neglected for too long. Nowadays, however, the water problem on the planet has exceeded the boundaries of countries suffering from shortages. It results in a constant search for programs of water conservation and use of alternative sources for human consumption, including the use of rainwater. This paper presents, as the main objective, the verification of the impact of rainwater harvesting system in single family residences at consumption of drinking water and urban drainage. Through the case study of a horizontal condominium in the city of Curitiba, Paraná, it presents a quantitative assessment of the volume of rain that is used and overflowed, using two methods of sizing tank volume: Method Practical German (ABNT 15,527 / 2007) and Method of Decree 293/2006 of Curitiba. Furthermore, it uses daily rainfall data since 1997 until 2013 to creates three demand scenarios of rainwater. With it is possible to verify the efficiency and confidence of the adopted systems in order to determine how much of the demand is met and how much water is retained in reservoirs.

CAPES / Os corpos hídricos têm suas características afetadas pela poluição difusa, por meio do carreamento de poluentes pelo escoamento superficial nos eventos de chuvas ou também por despejos pontuais. Esta pesquisa foi realizada nas cavas do Parque das Águas em Pinhais/PR e teve por objetivo avaliar a qualidade das águas e sedimentos dos corpos hídricos e a sua correlação com a poluição difusa. Foram analisadas algumas variáveis físico-químicas, bacteriológicas e de compostos orgânicos HPAs e n-Alcanos em 6 pontos, que podem indicar possíveis alterações na qualidade desses corpos hídricos. Estas cavas deverão futuramente ser destinadas para uso de recreação de contato secundário, como pesca e esportes náuticos pela LEI No 189/87 - Pinhais, indicando que as águas dessas cavas devem atender a resolução CONAMA 357/05, que estabelece limites para parâmetros físico- químicos, biológicos e de espécies metálicas que possam causar danos à saúde e ao ambiente. Para embasar a discussão dos resultados para HPAs e espécies metálicas em sedimento, utilizou-se a resolução CONAMA 344/04. Os limites indicados pelas resoluções do CONAMA 357/05 e 344/04, são valores de segurança. Com base nos resultados obtidos, identificou-se a influência das chuvas nas concentrações das variáveis analisadas. Através da comparação dos resultados com a Resolução CONAMA 357/05 para água doce de classe 2, pôde ser constatado que os parâmetros salinidade, OD, turbidez, amônia, nitrito, nitrato estão de acordo com os limites impostos pela resolução, a DBO a para maioria dos pontos analisados apresentou-se dentro dos limites, porém em um dos pontos excedeu o limite. Para Coliformes termotolerantes, a maior parte dos pontos se apresentou dentro dos limites estabelecidos pela resolução. A variável Sulfeto não atende a CONAMA 357/05. Dos sete metais analisados em água cádmio e ferro apresentam-se acima do limite para o CONAMA 357/05. Os metais cobre, zinco, cádmio, níquel e chumbo em sedimentos estão dentro do limite da resolução CONAMA 344/04, mas em alguns pontos amostrados os HPAs indicaram contaminação por elementos de origem petrogênica quando confrontados com os limites indicados nesta mesma resolução. Para evitar que os limites sejam excedidos, visto que alguns dos pontos amostrados estão muito próximos, ou extrapolando os limites indicados, faz-se necessário evitar a entrada de poluente nas cavas do parque em questão, devido ao grande risco de perder a qualidade destes corpos hídricos e prejudicar a sua função para a sociedade. A pesquisa permitiu identificar que o incremento da carga poluente é potencializado pelo escoamento superficial das chuvas, inferindo desta forma, a necessidade do controle da poluição difusa para a área do parque. Uma das possíveis soluções seria a implantação de sistemas de wetlands construídos, que podem funcionar como barreiras para a entrada de poluentes, principalmente nas cavas mais próximas às estruturas viárias pavimentadas. / The water bodies have the characteristics affected by diffuse pollution through the drift of pollutants in the runoff from rain events or also by occasional evictions. This research was conducted in pools of the Water Park in Pinhais/PR and aimed to assess the quality of waters and sediments of water bodies and their correlation with diffuse pollution. The analyses from some physico-chemical, bacteriological and organic compounds PAHs and n-alkanes in 6 points, indicated possible changes in the quality of these water bodies. These pools will be designed for future use of secondary contact recreation such as fishing and water sports in the LAW 189/87 - Pinhais-PR, indicating that the water pools must answer these CONAMA Resolution 357/05, which sets limits for physical- chemical, biological and metal species that may cause damage to health and the environment. To support the discussion of the results for PAHs in sediment and metal species, is used the CONAMA Resolution 344/04. The limits given by CONAMA resolutions 357/05 and 344/04, are safety values. Based on these results, we identified the influence of rainfall in the concentrations of all variables. By comparing the results with CONAMA Resolution 357/05 for freshwater class 2, it might be noted that the parameters salinity, dissolved oxygen, turbidity, ammonia, nitrite, nitrate comply with the limits imposed by resolution, for the DBO Most points analyzed was within the limits, but in one of the exceeded limit. For Fecal coliform, most points are presented within the limits established by resolution. The variable sulfide does not meet CONAMA 357/05. Of the seven metals analyzed in water cadmium and iron are found above the ceiling for CONAMA 357/05. The metals copper, zinc, cadmium, nickel and lead in sediments are within the limit of CONAMA Resolution 344/04, but in some sampling sites indicated PAH contamination source elements petrogenic when confronted with the limits specified in this same resolution. To avoid the exceeding the limits, since some of the points are very close, or extrapolating the limits, it is necessary prevent the entry of polluting the pools of the park in question, due to the high risk of losing the quality of these bodies water and impair its function for society. The research identified that the increase in pollution load is powered by the runoff of rainfall, implying thus the need for control of diffuse pollution to the park area. One of the possible solutions would be the deployment of constructed wetlands, which can act as barriers to the entry of pollutants, mainly pools nearest paved road structures.

The increased use of pesticides has resulted in a corresponding increase in concern for the effect they may have on the health of humans and other non-target organisms. The two main areas of concern are the toxicological effects that mixtures of pesticides may have as well as the endocrine disrupting effects. Although the individual pesticides may be present at concentrations below the levels deemed to be detrimental to health, it has been argued that their combined effect may still result in elevated health risks. Another important aspect of pesticide risk assessment requires a consideration of the breakdown products of pesticides and their effect on human health. There has been very little research into the effects of degradation products and this issue should be addressed as these could potentially pose a higher risk than their parent compounds. One of the most important bio-markers available for use is the ubiquitous enzyme acetylcholinesterase (AChE). This enzyme is responsible for one of the most important functions in the body; namely nerve impulse transmission, upon which all life depends. The inhibition of this enzyme indicates toxicity and as a subsequence, a threat to the organism’s well-being. Bioassays have also recently been developed to test chemicals for endocrine disrupting effects. These tests rely on a dose response equivalent to that of the most potent well known estrogen 17-β estradiol. Any chemical that has a measurable response is deemed to display endocrine disrupting effects. This first aim of this study was to investigate the toxicological and endocrine disrupting effects of three organophosphorus pesticides; aldicarb, parathion and demeton-S-methyl, in addition to two breakdown products; aminophenol and p-nitrophenol. Two carbamate pesticides; carbaryl and carbofuran were also analysed. The toxicological effects of mixtures of the parent pesticide compounds were tested to assess if any antagonistic, additive or synergistic effects were observed. This data was then used in conjunction with an artificial neural network to assess if individual pesticides could be distinguished from mixtures of pesticides. A final objective was to sample various Eastern Cape water sources, utilising the enzymatic assay to determine the presence of any of these pesticides in these samples. There were several conclusions drawn from this study. AChE was successfully used as an assay to test the toxicity of the pesticides under investigation, based on their inhibition of this enzyme. An important factor for consideration throughout the study was the need to establish basal and monitor AChE activity (i.e. the need to monitor AChE activity in the absence of any pesticide). This ensured accurate comparison of the results obtained. It was found that demeton-S-methyl was the most potent of these pesticides followed by carbaryl, parathion, aldicarb and finally carbofuran, and that carbofuran could potentiate AChE. The results indicated that pesticide mixtures generally exhibited an additive inhibitory effect on AChE, although at some concentrations of pesticides, synergistic and antagonistic effects were noted. From the data using mixtures of pesticides, a feed forward neural network was created that was successfully able to distinguish individual pesticides from mixtures within its training parameters. None of the pesticides tested displayed endocrine disrupting properties in the Yeast Estrogen Screen (YES), T47D-KBluc and MDA-kb2 bio-assays. Other studies reported mixed results in this regard and thus no final conclusions could be drawn. The Blaauwkrantz River, Kariega River, Sundays River, Swartkops River and Kowie River were all tested for pesticides and although positive results were recorded, conventional methods indicated that there were no pesticides in the rivers. There were, however, trace metals present which are known to inhibit AChE, thus causing a false positive result. These results indicated that AChE can be used as a high throughput initial pre-screening tool, but that it cannot serve as a substitute for more accurate conventional testing methods.

The nutrient dynamics in two contrasting estuaries and in the adjacent nearshore environment along the south-east coast of South Africa was investigated seasonally. Due to an inter-basin transfer of water from the Gariep Dam to the Great Fish River, the Great Fish estuary is a fresh water dominated, terrestrially driven system with an annual fresh water inflow of 250 – 650 x 10⁶ m³ per year. In contrast, the Kariega estuary is a fresh water deprived, marine dominated system with a fresh water inflow estimated at 2.5 – 35 x 10⁶ m³per year. The reduced fresh water inflow into the estuary is attributed to regular impoundments along the Kariega River. Water samples were collected from surface and subsurface layers along the length of the estuaries as well as from a series of transects occupied in the nearshore environment. Samples were analysed for nitrate, nitrite, ammonium, phosphate and silicate. Temperature and salinity were recorded at each station. A Land-Ocean Interactions in the Coastal Zone (LOICZ) budget was constructed for each estuary to describe the role of ecosystem-level metabolism as either a sink or a source of phosphorus, nitrogen and carbon. Seasonal variation in physico-chemical properties and nutrient concentrations in the Kariega estuary was minimal due to constant low inflow, while in the Great Fish estuary, concentrations varied in response to changes in flow rate. Nutrient concentrations were consistently higher in the Great Fish estuary than in the Kariega estuary, largely reflecting differences in fresh water inflow. During periods of high flow (32.92 m³.s⁻¹in the Great Fish River) dissolved inorganic nitrogen (DIN) concentrations in the Great Fish estuary were an order of magnitude higher than those recorded in the Kariega estuary. Results of the LOICZ budgeting procedures revealed that in spite of the contrasting hydrodynamic features, the estuaries behave in largely the same manner – both predominantly sources of nutrients with heterotrophic processes dominating over autotrophic actions and both were net denitrifyers during all surveys. This was, however, due to different sets of processes operating in the two estuaries, namely low nutrient concentrations resulting in microbial activity in the Kariega estuary, and riverine influx of nutrients and phytoplankton combined with a short residence time of the water in the Great Fish estuary. In the marine nearshore environment, higher nutrient concentrations were recorded adjacent to the Great Fish estuary than offshore of the Kariega estuary. This was due to a surface plume of less saline water leaving the Great Fish estuary, which acted as an ‘outweller’ of nutrients. Offshore of the Kariega estuary, on the other hand, the nutrient concentrations were characteristic of marine waters due to a lack of fresh water outflow from the estuary. Nutrient concentrations in the marine environment adjacent to the Kariega estuary were, at times, higher than those recorded within the estuary. This observation supports previous statements which suggest that the Kariega estuary is not an ‘outweller’ of dissolved nutrients and particulate material, but rather an extension of the marine environment.

The ecological position of micro-algae at the base of the aquatic food web makes them critical components of aquatic ecosystems. Their short generation time also makes them useful biological indicators because they respond quickly to changes in environmental condition, enabling timely identification and assessment of water quality changes. The inclusion of micro-algae as indicators in water resource regulation and management in South Africa has started recently, their more extensive use in biomonitoring and ecotoxicology programmes for water resource management would contribute to the South African policy if water resource protection. The standard algal growth inhibition assay with the species Pseudokirchneriella subcapitata is currently used for monitoring toxicity of in-stream and industrial wastewater discharges to freshwater micro-algae. The relevance of the data generated by standard toxicity bioassays has been questioned, since micro-algae in particular are extremely variable in their sensitivity to a range of contaminants and these standard species used may not occur in the local aquatic environment. As a result, international regulatory agencies, have recommended algal growth inhibition tests be changed from a single standard species to tests with a number of species. One recommendation, in addition to the use of standard toxicity tests, is the use of species isolated from the local environment which may be more relevant for assessing site specific impacts. This study investigated the value and application of locally isolated South African freshwater micro-algae in toxicity tests for water resource management and was carried out in three phases. The first phase involved isolating micro-algae from South African aquatic resources. Micro-algae suitable for toxicity testing were identified and selected using as set of criteria. Three (Scenedesmus bicaudatus, Chlorella sorokiniana and Chlorella vulgaris) out of eight successfully isolated species satisfied the prescribed selection criteria and these were selected as potential toxicity test species. The second phase focused on refining and adapting the existing algal toxicity test protocol (the algal growth inhibition assay) for use on the locally isolated algal species. The refinement of the test protocol was achieved by exposing the locally isolated species to reference toxicants in order to assess and compare their growth and sensitivity to the toxicants under the prescribed toxicity test conditions with that of the standard toxicity test species (Pseudokirchneriella subcapitata) and a commercial laboratory species (Chlorella protothecoides). During this phase, one of the three local species (Scenedesmus bicaudatus) was eliminated as a potential toxicity test species due to inconsistent growth. The third phase of the study involved assessing the sensitivity of the two remaining species (C. vulgaris and C. sorokiniana) to a range of toxicants (reference toxicants, salts, effluents and a herbicide) and comparing it to that of the standard toxicity test species P. subcapitata and C. protothecoides. The toxicants were selected based on their relative importance in the South African context, as well as the practicality of using these local micro-algae to routinely determine the impact of these toxicants on local aquatic resources. The growth of the four micro-algae was stimulated by the selected effluents. The standard toxicity test species P. subcapitata was ranked the most sensitive and of the four species to two reference toxicants and two inorganic salts. Chlorella sorokiniana was ranked the most sensitive of the three Chlorella species to two reference toxicants and two inorganic salts. The herbicide stimulated the growth of C. vulgaris while inhibiting the growth of the other species. Pseudokirchneriela subcapitata and C. sorokiniana showed high intra-specific variability in growth, which made it difficult to determine the effective concentrations of the herbicide and therefore compare the sensitivity of the species. This varied response of micro-algal species to toxicants may result in the biodiversity shifts in aquatic ecosystems, and also supports the recommendation of using a battery of different species to support more informed decisions in water resource management.