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Informal communities and their influence on water quality : the case of Umlazi.Gangoo, Arvana. January 2003 (has links)
Water is the most important resource which is essential for sustaining all life forms, since without it, life cannot exist and industry cannot operate. However, increasing concern is being expressed at the rate of degradation of this important resource, which, to a large extent, is due to the advent of industrialization and urbanization. The major causes for this concern is that the progress towards urbanization is often made without due regard to the consequences. Furthermore, the effect of man's social and industrial activities can be seen in the extent to which river water quality changes as a river flows from its source to the sea. Water which is returned to the river as effluent is rarely the same quality and is normally contaminated with some form of pollution. South Africa is a country where water is a scarce and precious resource. Coupled with low rainfall and a high evaporation rate, is the lack of basic services which are concentrated in areas where demands of the most vital resource is ever increasing. In addition, urbanization is experienced at a phenomenal rate, much of which is in the form of informal settlements. These constitute overcrowded "shacks" with no running water and sanitation facilities. Furthermore, imbalances in the ecosystem are created when humans strive to undertake the economic demands of the world resulting in poor environmental management practices and unhealthy living conditions. These communities lack basic services and as a result, resort to environmental degradation where the removal of vegetative cover, waste disposal and water pollution are evident. Furthermore, many of the informal settlements are situated in close proximity to water source, especially rivers. In the absence of sanitation, these communities make use of shallow pit latrines, river banks, etc. The potential for pollution is therefore very high in these communities. This provided the researcher with theThe purpose of the study was to determine the influence of the Umlazi informal community, L-SECTION on the water quality of the Umlaas River. The physical and chemical parameters viz., pH, E-coli, COD, turbidity, electrical conductivity, nitrate and phosphorous concentration were examined to provide the researcher with some indication of water quality. Water samples with an interval of 100 metres apart were collected upstream and downstream of the informal community. The samples were analysed at the Metro Waste Water management laboratory to determine the concentrations of the said variables. The purpose of upstream and downstream sampling was to enable the researcher to determine whether the difference in values between the two sets of data was significant or not. The statistical test was achieved through the application of the students t test. The results of the investigation indicate that water downstream of the informal community is of a poorer quality than that of upstream. The results of the application of the test for each set of variables (upstream vs downstream) reveals that the difference is significant. The findings of the study indicate that the informal community have a detrimental impact on water quality. Authorities responsible for management of water resources are required, as a matter of urgency, to implement nec~ssary steps to ensure that water quality is not impacted upon negatively. Failure in this regard could lead to the following: a decline in water quality and quantity; a reduction in economic opportunities; deteriorating standards of human health and safety as well as a decline in the diversity of plants, animals, and fish in our rivers. However providing proper sanitation to people living in informal settlements; improving the quality of lives of the homeless people who resort to squatting as well as ensuring that policies ensure that minimum standards requirements are met are just some of the steps in overcoming the problem in water quality. motivation for the study. / Thesis (M.A.)- University of Durban-Westville, 2003.
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Performance assessment in water supply and distributionCoelho, Sergio Carvalho de Matos Teixeira January 1996 (has links)
No description available.
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Evaluation of drinking and irrigation water quality in Njuli, MalawiForsberg, Agnes January 2014 (has links)
Good water quality is very central to a country's wellbeing. Clean water is required to ensureboth the health of the population and good ecological status of the country. It is thereforeimportant to continually conduct surveys to determine the status of the water used in, forexample, households, industries and agriculture.Elevated levels of metals, sulphate, nitrate and phosphate in drinking water can lead to poorhealth through consumption and reduced harvest when the water is used in irrigation.This report aimed at examining whether the water resources available in the vicinity of Njuliquarry in Chiradzulo, Malawi, meet the requirements of drinking and irrigation water. Thestudy found that most of the studied parameters were within the recommendations set by theMalawi Bureau of Standards (MBS) and the World Health Organization (WHO). However,conductivity in some of the water samples was higher than the recommendations. Both nitrateand iron concentrations were higher than recommended at a few locations.The study cannot conclude that the water from the water sources near the Njuli quarry containharmful levels of metals, nitrate, sulfate or phosphate.
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Occurrence, Prevalence, and Disinfection Potential of Tetracycline Resistance Genes and Tetracycline Resistant Bacteria in a Subtropical WatershedSullivan, Bailey Ann 02 October 2013 (has links)
Antibiotics are an important method for protecting human health. Unfortunately, the development of antibiotic resistance has decreased the effectiveness of antibiotics in treating disease and preventing deaths associated with bacterial infection. The objective of this dissertation research was to gain a better understanding of anthropogenic influences on occurrence of tetracycline resistance and use of traditional disinfection methods for the reduction of tetracycline resistant bacteria and genes. Culture based and molecular methods were used to evaluate the occurrence of tetracycline resistance in a rapidly urbanizing watershed, identify the dominant resistant organisms and resistance genes in the watershed, and evaluate the use of UV and chlorine to reduce the concentration of resistant bacteria and resistance genes.
Results from this research showed that tetracycline resistance was prevalent and is maintained in this study area. Several bacterial species (Aeromonas, Acinetobacter, Chryseobacterium, E. coli, Pseudomonas, and Serratia) made up the resistant population. The results also indicated that tet(W) was the major resistance gene in this watershed and that a majority of the resistant bacteria were capable of transferring their resistance. Landuse did not cause a difference in occurrence of resistant bacteria or resistance genes which suggests that a rapidly urbanizing watershed could experience resistance. It was also identified that environmental media (sediment and water) influence the occurrence and prevalence of resistant bacteria and resistance genes. The results indicate that streambed sediment may act as a reservoir for resistance and resistance might be transported in the water. Finally, the results showed that neither UV nor chlorine disinfection were effective in reducing tet(W) concentrations though the results varied greatly among species.
Results from this research indicate that preventing the occurrence and distribution of resistance gene in the environment is difficult, and resistance will most likely be maintained. Therefore, in order to prevent the spread of antibiotic resistance, it will be important to prevent antibiotic resistance from becoming established in the environment. This can be done by educating the public about the importance of misusing and mismanaging antibiotics. Additionally, classifying antibiotics for either human or veterinary use may help slow the development of resistance. This should prevent clinically important antibiotics from being used in sub-therapeutic doses, which could decrease the selective pressure in the environment. Also clinically relevant bacteria can be prevented from interacting with resistant bacteria in the environment by disinfecting human waste.
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Regional assessment of the effects of land use on water quality: A case study in the Oldman River Basin, AlbertaHowery, Jocelyn 11 1900 (has links)
Protecting and managing Canadian water resources in the face of growing cumulative effects and non-point source pollution from development (industrial, agricultural, and urban), depends on defensible, scientifically founded, watershed assessments. The objectives of this research were to broadly characterize the spatial and temporal patterns in water quality (total phosphorus and total nitrogen concentration, export and yield) across a land use disturbance gradient (forest, agriculture, urban) to elucidate pressures on water quality from specific landscape regions within the three headwater sub-basins of the Oldman River basin. While the water quality in the Oldman basin, remains fairly pristine, important spatial differences in nutrient production were evident between the upstream (predominantly forested) and the downstream (mixed agricultural/forested) reaches within the sub-basins. Using the pressure state response model as a framework to link landscapes to observed water quality, it was also found that phosphorus contamination may be an issue in the headwaters. / Water and Land Resources
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Rapid detection and molecular profiling of water-borne bacteriaHoefel, Daniel January 2005 (has links)
In this thesis, detection of active water-borne bacteria was achieved by combining flow cytometry with vital dyes that characterise the metabolic status of cells. Following optimisation, these techniques were applied to investigate the activity of bacteria exposed to disinfection, both in the laboratory and in real systems. Raw and potable waters from various locations around South Australia were then analysed to investigate relationships between numbers of active bacteria and those detected by traditional culture-based techniques. Flow cytometric cell sorting of active bacteria followed by 16S rRNA gene-directed PCR and denaturing gradient gel electrophoresis (DGGE) was then used to track the survival of bacteria through water treatment and into distribution. In doing so the identification of active bacteria not detected by culture was achieved. Finally, real-time PCR was optimised for detection of ammonia oxidising bacteria. This group of bacteria were responsible for loss of disinfection residual within a chloraminated distribution system. / thesis (PhD)--University of South Australia, 2005.
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Water quality changes across an urban-rural land use gradient in streams of the West Georgia PiedmontCrim, Jackie F., January 2007 (has links) (PDF)
Thesis (M.S.)--Auburn University, 2007. / Abstract. Vita. Includes bibliographic references (ℓ. 82-87)
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A bacterial water quality investigation of Canyon Lake, ArizonaHorak, William Frank, January 1974 (has links) (PDF)
Thesis (M.S. - Watershed Management)--University of Arizona. / Includes bibliographical references.
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Examination of the relationship between bottom sediment and overlying water quality in recreational watersKramer, Ricky Earl. January 1983 (has links) (PDF)
Thesis (M.S. - Renewable Natural Resources)--University of Arizona, 1983. / Includes bibliographical references (leaves 65-67).
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The use of a multiparameter bacterial aquatic toxicity testPill, Kenneth Goodman, January 1989 (has links) (PDF)
Thesis (M.S. - Hydrology and Water Resources)--University of Arizona, 1989. / Includes bibliographical references (leaves 147-156).
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