Search

South African rivers generally receive waste from inadequate wastewater infrastructure, mines, and farming activities, among others. The uMsunduzi River in KwaZulu-Natal, South Africa, is among these recipients with recorded poor to very poor water quality. To identify parts of the uMsunduzi River that are polluted by Cryptosporidium and Escherichia coli (E. coli), this study mapped out pollutants emanating from point and non-point sources using the Soil and Water Assessment Tool (SWAT). Streamflow calibration in the upper and lower reaches of the catchment showed good performance with R² of 0.64 and 0.58, respectively. SWAT water quality output data were combined with a Quantitative Microbial Risk Assessment (QMRA) to understand the microbial health implications for people using river water for drinking, recreational swimming, and non-competitive canoeing. QMRA results for Cryptosporidium and pathogenic E. coli showed that the probability of infection for most users exceeds the acceptable level for drinking and recreation as outlined in the South African water quality guidelines, and by the World Health Organization (WHO). The results of this study can be used as a baseline to assess the economic and health implications of different management plans, resulting in better-informed, cost-effective, and impactful decision-making. [ABSTRACT FROM AUTHOR]

There has been a rising interest in the levels, diversity and potential impacts of yeasts in aquatic environments. Some of the species isolated from such niches are known pathogens or have pathogenic and antifungal resistance features. This deems it necessary to understand the characteristics and potential health implications of such environmental yeasts species. Studies on these subjects are limited. Most studies on aquatic yeasts have linked them to water pollution. However, the current gold standards to determine microbial pollution of water use bacteria as the main indicator organisms. Including yeasts in water quality standards may provide a different dimension on the quality of water when determining its fit-for-use properties. Pathogenic yeasts cause superficial infections or life-threatening infections, especially in immunocompromised people. Some of the yeast species isolated in recent studies were resistant to commonly used antifungal agents of clinical and veterinary relevance. With the high prevalence rate of HIV in sub-Saharan Africa, particularly in South Africa, antifungal resistance is a public concern as it poses serious medical and economic challenges. Most available studies are concerned with clinical environments only. There is, thus, a need to review the literature that also focuses on aquatic environments. [ABSTRACT FROM AUTHOR]

weight factors (WFs) were developed for surface raw water pollution indicator variables in Vaal River's Upper and Middle Vaal sub-basins, in South Africa. The overall objective was to formulate a quantifiable ranking system to indicate importance of pollutant variables given their established effects on human and environmental health. Multi-criteria decision analysis (MCDA) was applied to qualitative data that were obtained from South Africa's target water quality ranges as well as from literature which represented expert opinion. The human and environmental health effect choice sets were ranked from ito 5 on nine pollutant variable criteria: NH3/NH4+, Cl-, conductivity (EC), dissolved oxygen (Do), pH, F, NO3-/NO2-, PO43- and SO42-. The weighted-sum method (WSM) then assigned highest and lowest normalised weights (NWs) to F- and Cl-, respectively, for human health effects (ϵhh) alternative. Highest and lowest NWs were assigned to NH3/NH4+ and EC, respectively, for environmental health effects (ϵhh) alternative. After aggregating the ϵhh and ϵeh WFs, resultant values ranked the variables from highest to lowest as follows: F-> NO3-/NO2->/NH3/NH4+>DO> pH>SO42->PO43-> EC>Cl-. The results represented the importance of variables given their established effects on human and environmental health. It was concluded that WFS provided a quantifiable barometer which could signal harmful exposure to elucidate negative effects of using polluted surface raw water in the study area. The values could be incorporated into water quality models like water quality indices. The approach could be used to develop WFs for other sites, taking into account issues like the site's pollution variables of concern as well as using a ranking key constructed from established literature. [ABSTRACT FROM AUTHOR]

South Africa is a country of contrasts with far ranging variations in climate, precipitation rates, cultures, demographics, housing levels, education, wealth and skills levels. These differences have an impact on water services delivery as do expectations, affordability and available resources. Although South Africa has made much progress in supplying drinking water, the same cannot be said regarding water quality throughout the country. A concerted effort is currently underway to correct this situation and as part of this drive, water safety plans (WSP) are promoted. Rand Water, the largest water services provider in South Africa, used the World Health Organization (WHO) WSP framework as a guide for the development of its own WSP which was implemented in 2003. Through the process of implementation, Rand Water found the WHO WSP to be much more than just another integrated quality system. [ABSTRACT FROM AUTHOR]

A short-term assessment of water, sanitation, hygiene and home-based care services in two rural and two peri-urban communities in South Africa was made using specially designed questionnaires. The results from this assessment indicated the shortcomings of various sections in the service provision to people affected and living with HIV/AIDS in South Africa. This paper is a summarised version of the assessment and aims to give an indication of the inadequacies of some of these services. [ABSTRACT FROM AUTHOR]

The South African Department of Water Affairs and Forestry (DWAF) has started developing a strategy to regulate activities and water uses by the agricultural sector that could impact on the water resource quality. The aim would not be to over-regulate the sector, but to protect the water resource where necessary. Most of these activities constitute diffuse sources of potential pollution. The strategic process will start with investigative discussions with major stakeholders and determining the strategic context and current situation. The latter will consist of a detailed literature and stakeholder survey, and an evaluation of existing agricultural activities. The next steps of determining a vision and the setting of strategic objectives will be done with active participation by the major players. An action plan will be developed to achieve the set objectives. Important components of the strategy will be to: classify activities according to their risk to the water resource, taking into account the sensitivity of the water resource; set regulatory measures in accordance with the risk posed by the activity (measures could include the promulgation of regulations, general authorisations and/or issuing of licenses); harmonise and link the process with existing relevant processes and guidelines within DWAF and other government departments; review existing guidelines; sign agreements with relevant government departments and the agricultural sector; and provide training, built capacity and raise awareness during and after the process. [ABSTRACT FROM AUTHOR]

A survey of the microbiological quality of water from 194 boreholes (97 privately owned and 97 communal boreholes) in the rural Thitale-Hlanganani area of the Limpopo Province, South Africa was carried out between August 2002 and August 2003. Very little information on the microbiological quality of privately-owned boreholes in rural communities is available raising concerns about the safety of these groundwater supplies. In this study, levels of total coliforms, thermotolerant (faecal) coliforms, faecal enterococci, Clostridium perfringens (vegetative cells and spores) and somatic coliphages were determined for community and privately-owned borehole water. The average counts for total coliforms, faecal coliforms, faecal enterococci and Clostfidium perfringens exceeded the South African recommended guideline limits of 0-10 counts.100 ml-1 for total coliforms and 0 counts. 100 ml-1 for faecal coliforms, faecal enterococci and Clostridium perfringens respectively. Comparisons between the levels of indicator bacteria present in private and communal boreholes during dry seasons indicated a statistical difference for faecal enterococci bacteria (p = 0.005) and Clostridium perfringens (p = 0.08). Comparisons between the levels of indicator bacteria present in private and communal boreholes during rainy seasons indicated statistical differences between total coliforms (p = 0.05), faecal coliforms (p = 0.03) and Clostridium perfringens (p = 0.009) bacteria. No significant differences in the presence of somatic coliphages in both private and communal borehole water were see. The results indicated the need for environmental impact assessment studies to monitor the microbiological quality of groundwater sources in rural communities. [ABSTRACT FROM AUTHOR]

The concept of safe water is defined by three principles: the health-related quality must be suitable, the supply/source must be accessible and the water must constantly be available in quantities sufficient for the intended use. If any one (or more) of these three elements is missing from a water services improvement programme, providing safe water is not successfully achieved. A study in a deep rural area in South Africa showed that providing small communities, using untreated river water as their only water source, with good quality water through a piped distribution system and accessible at communal taps did not fall within our parameters of safe water. The parameters for measuring the three principles were: absence of Escherichia coli in drinking water samples; accessibility by improving tap distances to within 200 m from each household; availability by assessing whether households have at least 25 L per person per day. Results show that although E. coli levels were reduced significantly, households were still consuming water with E. coli numbers at non-compliant levels. Access (distance) was improved from an average of 750 m from households to river source to an average of 120 m to new on-tap source points. This did not result in significant increases in household quantities, which on average remained around 18 L per person per day. [ABSTRACT FROM AUTHOR]

A customised Water-related Quantitative Microbial Risk Assessment (WRQMRA) process was used to determine risk of infection to water ingested by users in the south-eastern Free State, South Africa. The WRQMRA consisted of an observed-adverse-effect-level approach (OAELA) and a quantitative microbial risk assessment (QMRA). The OAELA was based on the occurrence of E. coli in the study waters to determine the possible risk of infection and the QMRA probable risk of infection by salmonellae. The WRQMRA was applied to recreational surface resource waters as well as waters from an unprotected spring and waters from the treated municipal supply that were stored in containers for domestic purposes. E. coli numbers were measured against expected infection levels expressed in water quality guidelines, while Salmonella counts were calculated to give the probable infection risk (Pi). Ingestion was based on intake volumes compiled for the various water uses. E. coli occurred in numbers <106 in the surface waters, while the untreated spring and treated supply water contained E. coli of <10² and <10¹ respectively. Salmonella occurred in numbers of <10³ in recreational waters, and <10-1 in water used for domestic purposes. A single exposure to the mean (as well as 95th percentile) risk was calculated using a β-Poisson dose-response model at ingestion volumes of 100 mL (for full-contact recreation) and 1,318 mL (for domestic water use). Both the OAELA and the QMRA approaches indicated a risk of infection to recreational and domestic water users, even for a single exposure event, with the OAELA either over- or under-estimating the risk of infection for singular exposure events. This indicated that this method, used on its own, could not reliably predict a realistic risk of infection. It is recommended that the full WRQMRA process be used, and further developed to address several uncertainties that became evident during this study. [ABSTRACT FROM AUTHOR]

The microbial quality of several, usually untreated, surface domestic water sources, used by rural communities in the Venda Region of South Africa, was assessed to gauge their fitness for human consumption and to highlight the possible impact of waterborne diseases. The water sources studied were six points on the Levubu River and the rivers Mutale, Ngwedi, Tshinane, Makonde, Mutshindudi and Mudaswali. Total and faecal coliform, heterotrophic bacteria, enterococci and coliphage counts were used as indicators/surrogates to estimate the degree of bacterial and viral contamination respectively by standard methods. The presence of potential bacterial agents of diarrhoea such as Salmonella, Shigella, Campylobacter, Plesiomonas, Aeromonas and Vibrio was also determined. Results showed that the ranges of counts with regard to all the water sources investigated were 2.9 × 102 - 6.3 × 104 CFU/100 mL for faecal coliforms, 6.0 × 102 - 3.7 × 104 CFU/100 mL for total coliforms, 1.8 × 102 - 1.3 × 106 CFU/mL for heterotrophic plate count, 1.0 × 101 - 3.7 × 104 CFU/100 mL for enterococci and 0-13 PFU/100 mL for coliphages. These values are far higher than the acceptable maximum limits prescribed for South Africa by the Dept of Water & Forestry and the Water Research Commission - 0 CFU/100 mL, 5 CFU/100 mL, 1.0 × 102 CFU/mL, 0 CFU/100 mL and 1 PFU/100 mL for faecal coliforms, total coliforms, heterotrophic bacteria, enterococci and coliphages respectively. Salmonella, Shigella, Vibrio cholerae, Campylobacter, Aeromonas and Plesiomonas were isolated from several of the water sources investigated. The use of these water sources for drinking and domestic purposes poses a serious threat to the health and well being of the users and calls for urgent government intervention. [ABSTRACT FROM AUTHOR]

To investigate the effect of long storage and household containers on the microbiological quality of water in a rural community, borehole water from the reservoir and seven standpipes was used. Borehole water was stored for a period of 72 h in household containers (polyethylene-PE and galvanised steel-GS), which are commonly used by the rural community of Mgquba village. Heterotrophic plate count (HPC) and faecal coliform bacteria were used as the main parameters. Standard spread plate procedure and membrane filtration method were used to enumerate HPC and faecal coliform bacteria respectively. The results of this study revealed three factors that affected the microbiological quality of drinking groundwater used by the rural community of Mgquba village: the intake water, the duration of storage and the household container. The initial levels of faecal coliform (range of faecal coliforms: 0.1–2 cfu · 100 m-1 in the reservoir water, 0–57 cfu · 100 ml-1 in the standpipe water) and HPC bacteria (average counts: 5 log cfu · ml-1 in the reservoir water, 7 log cfu · ml-1 in the standpipe water) in both reservoir and standpipe waters far exceeded the limit allowed by the South African Water Quality Guidelines for Domestic Use (no risk target water quality range: 0 count · 100 ml-1 for faecal coliforms, 0–100 counts · ml -1 for HPC bacteria). The persistence of faecal coliforms in polyethylene-stored water was observed after 72 h of storage while their complete elimination in the galvanized steel-stored water occurred after 48 h of storage. Escherichia coli was the most dominant faecal coliform found in the initial and stored waters. Although the yield of HPC bacteria increased in water samples during storage in both polyethylene and galvanised steel containers, the microbiological quality of drinking groundwater deteriorated consistently with the length of the storage. Water stored for 72 h displayed a higher yield of HPC (average counts: 7 log-8 log cfu · ml-1 in PE-stored water, 6 log-8 log cfu · ml-1 in GS-stored water) than the water stored for 48 h or 24 h (average counts: S log-8 log cfu · ml-1 in PE-stored water, 5 log-7 log cfu · ml-1 in GS-stored water). Statistical analysis indicated a significantly higher number of HPC bacteria in the water stored in polyethylene than in the water stored in galvanised steel (P=0.02). Significant differences in HPC bacteria were also noted within household container-stored water from standpipes (P=0.0001 for PE, P=0.0002 for GS). [ABSTRACT FROM AUTHOR]

Analyzes the training and education needs and programs for water practitioners to address the problem of severe water supply and water quality problems in South Africa. Training of technical staff to operate and maintain water treatment and supply schemes; Education of high-level scientists and engineers to develop technologies.

Discusses an integrated water quality monitoring system for ambient water quality and point and nonpoint sources of aquatic pollution in South Africa. Integrated catchment management; Elements of a managed water cycle and spatial desegregation; Standard spatial organization for water quality monitoring.

Describes an approach to effective water quality management in South Africa. Integrated catchment management; Water policy; Resource allocation for pollution discharge; Water quality protection.

A situational analysis of a peri-urban catchment experiencing microbial water quality problems was carried out using data collected over two and a half years. The water and land use in the area was determined. The main sources of pollution were identified and the effects of dilution and bacterial die-off on water quality were evaluated by modelling the level of faecal coliforms along the length of the river using the QUAL2E model. As a result of the assessment, water quality goals were set for the catchment and suggestions were made for the improvement of microbial quality. Certain areas of the catchment are densely populated and both developed and informal settlements exist. Water is mainly used for domestic and recreational purposes. The river receives diffuse source discharges as well as point source discharges from four wastewater treatment plants and an industrial site. Assessment of indicator organism and pathogen analyses indicated that the main factors affecting the microbial quality were discharges from the sewage plants and runoff from informal settlement areas. The industrial activities in the catchment did not have a major effect. Modelling runs predicting faecal coliform levels demonstrated that bacterial die-off did not result in a significant improvement to the microbial water quality in the catchment. [ABSTRACT FROM AUTHOR]

Efforts to provide water to developing communities in South Africa have resulted in various types of water supplies being used. This study examined the relationship between the type of water supply and the quality of water used. Source (communal taps, private outdoor and indoor taps) and point-of-use water samples were examined for heterotrophic plate counts (HPC), total and faecal coliforms, E. coli, and coliphages. Ten percent of samples were also analysed for enteric viruses, Giardia and Cryptosporidium. Approximately 320 households were included in a case-control study. In addition, a cross-sectional study was conducted. Both studies examined the relationship between different types of water facilities and diarrhoea among pre-school children. The source water was of good microbial quality, but water quality was found to have deteriorated significantly after handling and storage in both case and control households, exceeding drinking water quality guideline values by 1-6 orders of magnitude. Coliphage counts were low for all water samples tested. Enteric viruses and Cryptosporidium oocysts were not detected. Giardia cysts were detected on one occasion in case and control in-house samples. Comparisons of whether in-house water, after handling and storage, complied with water quality guideline values demonstrated households using communal taps to have significantly poorer quality than households using private outdoor or indoor taps for HPC and E. coli (χ² = 14.9, P = 0.001 χ² = 6.6, P = 0.04 respectively). A similar trend (although not statistically significant) was observed for the other microbial indicators. The cross-sectional study demonstrated an apparent decrease in health risk associated with private outdoor taps in comparison to communal taps. This study suggests that a private outdoor tap is the minimum level of water supply in order to ensure the supply of safe water to developing communities. [ABSTRACT FROM AUTHOR]

South Africa is currently experiencing rapid urbanization, much of which is in under-serviced and informal settlements. This has resultedin significant nonpoint source related water quality problems in these settlements. Although contamination of water resources is a physical process, which is related to the settlement character and service levels, the institutional and socio-economic conditions in the settlements largely govern its manageability. Understanding the settlement characteristics that exacerbate or mitigate water quality problems istherefore necessary for the identification and selection of appropriate management solutions. This paper outlines the key physical, institutional and socio-economic factors that contribute to water quality impacts from peri-urban settlements, and explores the implications ofthese characteristics for management of the nonpoint source impacts. [ABSTRACT FROM AUTHOR]

South Africa currently has one of the highest rates of urbanization in the world causing a significant increase in surface water runoff. This, in turn, causes increased flooding and a significant decrease in water quality due primarily to the accumulation of pollutants. The need exists to manage urban stormwater runoff on an integrated catchment basis, thereby reducing the negative impact of urbanization on the environment and quality of life. In this paper, details on how existing problem areas can be identified and ranked, the use of Best Management Practices (BMPs) to reduce the impacts of urbanization on the environment and the effectiveness of BMP's are discussed and illustrated, based on expertise gained from studies in South Africa as well as visits to the USA and Australia. [ABSTRACT FROM AUTHOR]