Safe drinking water is a basic human right. This study mainly focused on the physicochemical and microbiological drinking water quality of selected rural, peri-urban and urban communities and schools in the North West Province, South Africa. Parameters measured to determine the physico-chemical quality of drinking water were temperature, pH, total dissolved solids (TDS), electric conductivity, carbonate hardness, total hardness, NO2 -, NO3 - and chlorine. These parameters indicated hard water in the informal settlement (Sonderwater) as well as in the rural area (Ganyesa). Nitrate content were troubling for both areas, and total dissolved solids were higher than the standard in the water from Ganyesa. For microbiological quality of the water, heterotrophic plate count (HPC) bacteria, total coliforms, faecal coliforms, faecal streptococci, and staphylococci were enumerated on appropriate selective media using standard procedures. In the water from Sonderwater, faecal indicator bacteria were isolated, but none were found in the water from Ganyesa. Heterotrophic plate count bacteria and total coliforms were detected at levels above the standard in water samples from both areas. Staphylococci and faecal streptococci were present in low numbers in the water from both sites. Faecal coliforms isolated from Sonderwater showed multiple antibiotic resistances to beta-lactams. Identification of faecal coliforms from Sonderwater by API 20E strips and sequencing showed that they were Aeromonas spp. and Enterobacter spp.. Bacteria in the water from Sonderwater were tested for the potential to form biofilms. Scanning electron microscopy revealed multi-species biofilms developing in the water container after 5 days of storage. Water was sampled from four areas outside of Potchefstroom to determine a settlement gradient in water quality. Areas ranged from a formal area, through an established informal area and a newly established informal area to the newest established informal area. The water from these areas was classified as hard according to physico-chemical parameters measured, and TDS for the water from all areas were above the standard for domestic use. The established informal area had high numbers of total coliforms present in the water. Staphylococci and HPC bacteria were detected in levels higher than the standard for domestic use in all water samples. No faecal coliforms were found in the water from any of the areas. There was no visible gradient in the water quality between the areas. The water samples collected from rural, peri-urban and urban schools were also analysed in terms of physico-chemical and microbiological parameters. Water from all schools was classified as hard water. Only one school (peri-urban) had a pH above the standard. One rural school and one peri-urban school had TDS and electrical conductivity levels above the standard for domestic use. All rural and peri-urban schools had alarmingly high levels of nitrates present in the water. These schools receive groundwater as drinking water. Total coliform bacteria were present at high levels in all water samples from the schools. Rural and peri-urban schools presented levels of staphylococci and HPC bacteria higher than the standard for domestic use. Streptococci were present in water from some of the rural and peri-urban schools and one urban school. Faecal coliform/faecal streptococci ratios for rural schools indicated faecal pollution potentially of human origin, and in other schools faecal pollution from both human and animal origin. Before the vacation, faecal coliform bacteria were detected in water from all rural schools, two peri-urban schools and one urban school. After the vacation, faecal coliforms were only detected in water from two rural schools and one peri-urban school. Faecal coliforms identified and characterized showed multiple antibiotic resistances to beta-lactams, oxy-tetracycline and trimethoprim. Identification by API 20E strips and sequencing confirmed that faecal coliforms from schools were Escherichia coli and Klebsiella spp. It was concluded that water from Sonderwater were of poor quality and water from Ganyesa were acceptable with only the nitrates a troubling factor. There was no settlement gradient observed in terms of water quality between areas. Water from rural schools were generally of unacceptable quality in terms of both physico-chemical and microbiological parameters. The water quality of these schools was also very poor when compared to urban schools. Periurban schools had water quality better than rural schools, but poorer than urban schools. Surveys of water quality are recommended for all areas sampled, and education on the sanitary quality of water and related health implications is advisable for residents of informal and rural areas. / Thesis: B.Sc. Microbiology and Biochemistry School of Environmental Science and Development Faculty of Natural Sciences North-West University: Potchefstroom campus 2006.

Safe drinking water is a basic human right. This study mainly focused on the physicochemical and microbiological drinking water quality of selected rural, peri-urban and urban communities and schools in the North West Province, South Africa. Parameters measured to determine the physico-chemical quality of drinking water were temperature, pH, total dissolved solids (TDS), electric conductivity, carbonate hardness, total hardness, NO2 -, NO3 - and chlorine. These parameters indicated hard water in the informal settlement (Sonderwater) as well as in the rural area (Ganyesa). Nitrate content were troubling for both areas, and total dissolved solids were higher than the standard in the water from Ganyesa. For microbiological quality of the water, heterotrophic plate count (HPC) bacteria, total coliforms, faecal coliforms, faecal streptococci, and staphylococci were enumerated on appropriate selective media using standard procedures. In the water from Sonderwater, faecal indicator bacteria were isolated, but none were found in the water from Ganyesa. Heterotrophic plate count bacteria and total coliforms were detected at levels above the standard in water samples from both areas. Staphylococci and faecal streptococci were present in low numbers in the water from both sites. Faecal coliforms isolated from Sonderwater showed multiple antibiotic resistances to beta-lactams. Identification of faecal coliforms from Sonderwater by API 20E strips and sequencing showed that they were Aeromonas spp. and Enterobacter spp.. Bacteria in the water from Sonderwater were tested for the potential to form biofilms. Scanning electron microscopy revealed multi-species biofilms developing in the water container after 5 days of storage. Water was sampled from four areas outside of Potchefstroom to determine a settlement gradient in water quality. Areas ranged from a formal area, through an established informal area and a newly established informal area to the newest established informal area. The water from these areas was classified as hard according to physico-chemical parameters measured, and TDS for the water from all areas were above the standard for domestic use. The established informal area had high numbers of total coliforms present in the water. Staphylococci and HPC bacteria were detected in levels higher than the standard for domestic use in all water samples. No faecal coliforms were found in the water from any of the areas. There was no visible gradient in the water quality between the areas. The water samples collected from rural, peri-urban and urban schools were also analysed in terms of physico-chemical and microbiological parameters. Water from all schools was classified as hard water. Only one school (peri-urban) had a pH above the standard. One rural school and one peri-urban school had TDS and electrical conductivity levels above the standard for domestic use. All rural and peri-urban schools had alarmingly high levels of nitrates present in the water. These schools receive groundwater as drinking water. Total coliform bacteria were present at high levels in all water samples from the schools. Rural and peri-urban schools presented levels of staphylococci and HPC bacteria higher than the standard for domestic use. Streptococci were present in water from some of the rural and peri-urban schools and one urban school. Faecal coliform/faecal streptococci ratios for rural schools indicated faecal pollution potentially of human origin, and in other schools faecal pollution from both human and animal origin. Before the vacation, faecal coliform bacteria were detected in water from all rural schools, two peri-urban schools and one urban school. After the vacation, faecal coliforms were only detected in water from two rural schools and one peri-urban school. Faecal coliforms identified and characterized showed multiple antibiotic resistances to beta-lactams, oxy-tetracycline and trimethoprim. Identification by API 20E strips and sequencing confirmed that faecal coliforms from schools were Escherichia coli and Klebsiella spp. It was concluded that water from Sonderwater were of poor quality and water from Ganyesa were acceptable with only the nitrates a troubling factor. There was no settlement gradient observed in terms of water quality between areas. Water from rural schools were generally of unacceptable quality in terms of both physico-chemical and microbiological parameters. The water quality of these schools was also very poor when compared to urban schools. Periurban schools had water quality better than rural schools, but poorer than urban schools. Surveys of water quality are recommended for all areas sampled, and education on the sanitary quality of water and related health implications is advisable for residents of informal and rural areas. / Thesis: B.Sc. Microbiology and Biochemistry School of Environmental Science and Development Faculty of Natural Sciences North-West University: Potchefstroom campus 2006.

Bacterial water pollution is a significant problem because it is associated with reduction in the ‘quality’ of water systems with a potential impact on human health. Faecal indicator bacteria (FIB) are usually used to monitor the quality of water, and to indicate the presence of pathogens in water bodies. However, enumeration alone does not enable identification of the precise origin of these pathogens. This study aimed to monitor the quality of bathing water and associated fresh water in and out of the ‘bathing season’ in the UK, and to evaluate the use of microbial source tracking (MST) such as the host-specific based polymerase chain reaction (PCR) and quantitative PCR (qPCR) to recognize human and other animal sources of faecal pollution. The culture-dependent EU method of estimating FIB in water and sediment samples was performed on beach in the South Sands, Kingsbridge estuary, Devon, UK- a previously ‘problematic’ site. FIB were present at significant levels in the sediments, especially mud, as well as fresh water from the stream and pond flowing onto South Sands beach. However, the quality of bathing water was deemed to be ‘good’ and met with the EU bathing water directive 2006. Using MST it was possible to successfully classify the nature of the source from which the bacteria came. PCR was applied to detect the Bacteroides species 16S rRNA genetic markers from human sewage and animal faeces. All water and sediment samples displayed positive results with a general Bacteroides marker indicating the presence of Bacteroides species. Host-specific PCR showed the human Bacteroides genetic marker only in the sediment of the stream. However, limitations in the ‘types’ of probes available and in the persistence of these markers were identified. Thus, novel dog-specific Bacteroides conventional PCR and qPCR primer sets were developed to amplify a section of the 16S rRNA gene unique to the Bacteroides genetic marker from domestic dog faeces, and these were successfully used to quantify those markers in water samples at a ‘dog permitted’ and ‘dog banned’ beach (Bigbury-on-Sea, Devon, UK). Generic, human and dog Bacteroides PCR primer sets were also used to evaluate the persistence of Bacteroides genetic markers in controlled microcosms of water and sediment at differing salinities (< 0.5 and 34 psu) and temperature (10 and 17 ºC). The rates of decline were found did not differ significantly over 14 and 16 days for the water and sediment microcosms, respectively. Beach sediments which were studied in this project may act as a reservoir for adhesive FIB, and this was confirmed using fluorescence in situ hybridisation (FISH). The similarity in the persistence of these Bacteroides 16S rRNA genetic markers in environmental water and sediment suggests that viable but non-culturable (VBNC) Bacteroides spp. do not persist in the natural environment for long. Therefore, 16S rRNA genetic markers can be of value as additional faecal indicators of bathing water pollution and in source tracking. Thus, in this study MST methods were successfully used and in future applications, dog-specific primer sets can be added to the suite of host-specific Bacteroides genetic markers available to identify the source(s) of problem bacteria found on failing beaches.

Dans de nombreux pays en développement, la qualité médiocre de l'eau constitue une menace majeure pour la santé humaine. Par ailleurs, le manque d'accès à l'eau potable et à l'assainissement sont un frein majeur au développement. La Fleuve Rouge est le deuxième plus grand fleuve au Vietnam et constitue la principale source d'eau pour la population du Nord-Vietnam. Cette thèse présente les résultats des observations et de la modélisation des bactéries indicatrices de la contamination fécales (BICF) et du carbone organique (CO) dans la Fleuve Rouge. Le modèle Seneque/RIVERSTRAHLER utilisant l’ensemble des données recueillies a permis d'étudier la dynamique et la répartition saisonnière des BICF et du CO dans la Fleuve Rouge et ses affluents. Un scénario, basé sur l’évolution démographique et les changements d’usage des terres prévus à l'horizon 2050, a montré une augmentation limitée des nombres des BICF par rapport à la situation actuelle. Ceci est particulièrement le cas pour la ville d’Hanoi même si la population devrait tripler d'ici 2050. Les apports en CO et la respiration hétérotrophe résultant du CO abouti à un système qui est une forte source en CO2 pour l’atmosphère. Les résultats du modèle reflètent également l'importance des différents usages des terres, le débit et la prédominance des sources diffuses relatifs aux sources ponctuelles sur les BIFC et CO dans le Fleuve Rouge. Cette thèse fournit de nouvelles informations sur les teneurs en BICF et CO dans la Fleuve Rouge ainsi qu’une base de discussion pour les décideurs sur la gestion future des eaux usées rejetés dans ce Fleuve. / In many developing countries, poor water quality poses a major threat to human health and the lack of access to clean drinking water and adequate sanitation continues is a major brake on development. The Red River is the second largest river in Vietnam and constitutes the main water source for the population of North Vietnam. This thesis presents the results from observations and modeling of both faecal indicator bacteria (FIB) and organic carbon (OC) in the Red River system, North Vietnam. The objective of this work was to measure FIB numbers and OC concentrations in this system and then to model these parameters in order to investigate scenarios for 2050 when population in the area is estimated to have doubled. The dataset was then modeled using the Seneque/Riverstrahler model in order to investigate the dynamics and seasonal distribution of FIB and OC in the Red River and its upstream tributaries. A scenario, based on the predicted changes in future demographics and land use in the Red River system for the 2050 horizon, showed only a limited increase of FIB numbers compared with the present situation. This was particularly the case in Hanoi even though the population is expected to triple by 2050. The OC inputs and the resulting heterotrophic respiration of this OC resulted in a system that was a strong CO2 source. The model results also reflected the importance of land use, discharge and the dominance of non-point sources over point sources for FIB and OC in the Red River. This thesis provides some new information on FIB in the Red River as well as providing a base for discussion with decision makers on the future management of wastewater in the Red River.