Glen, South Africa
Glen, South Africa

Time filter

Source Type

News Article | February 15, 2017

Dr Johnson participated in the Salvation Army’s Angel Tree Program in which staff and patients “adopted” children in need over Christmas and purchased a gift for them. In addition, staff decorated christmas trees in various themes and raffled them off to raise money for A Spring of Hope. She opened her doors to the community for free photos with Santa. The event raised funds for A Spring of Hope which brings running water to underprivileged schools in South Africa. A Spring of Hope partners with rural schools in South Africa to deliver fresh, clean water to school children and sustainable permaculture programs. Their goal is to provide them the resources they need to promote learning and promising futures for their students. They begin by drilling boreholes (water wells) at schools, ensuring that each of their schools has access to a clean, sustainable source of water for drinking, sanitation, irrigation, and food preparation. They are supported by House of Mandela; WESSA (people caring for the earth), Rand Water Foundation, ERM Group foundation, South African Airways and Irie Foundation. “2,402 schools in South Africa have no water supply” - The world water crisis poses a serious threat to all of our futures, especially those living in poverty. In Sub-Saharan Africa, both the poverty rate and proportion of rural houses not using improved water sources are over 50%. (Source: UN MDG) The availability of clean water dramatically improves health and, hence, productivity. The lack of water in schools and homes is one of the main reasons children in developing areas do not attend school. Water is an investment in the future. Dr Johnson believes that children are our future. In the words of Dr Johnson: “Premier Smile Center is committed to giving back to local and international causes. I believe we can all make a difference in our own way.” She had challenged her patients to donate towards a borehole in one of these schools, this year. She would match every donation, dollar for dollar. The Christmas event topped off the year-long fundraising efforts and Premier Smile Center and its patients were able to raise enough money to drill a borehole in an underprivileged school in rural South Africa. Drilling for water has already started! This is just the beginning for Dr Johnson. A Spring of Hope also teaches these schools to plant vegetable gardens to supplement school meals. Their 3rd effort is sanitation. 11,450 schools still use pit latrine toilets. Combined with a lack of water to wash their hands, disease amongst the children is a major concern. Premier Smile Center is committed to fighting poverty and disease and challenges everyone to help them. About Premier Smile Center: Dr Johnson is originally from South Africa and received her dental degree in 1995. She completed a General Practice Residency at University of Illinois at Chicago. She enjoys working with people and is committed to their comfort and satisfaction. At Premier Smile Center their mission is to provide their patients with excellence in general, cosmetic and specialty dentistry. They emphasize gentle and preventative care so as to help achieve healthy teeth and gums for life. They want everyone to have a healthy, clean and white smile.

Fadal M.F.,University of Johannesburg | Haarhoff J.,University of Johannesburg | Marais S.,Rand Water
Drinking Water Engineering and Science | Year: 2012

This paper proposes a three-parameter mathematical model to describe the particle size distribution in a water sample. The proposed model offers some conceptual advantages over two other models reported on previously, and also provides a better fit to the particle counting data obtained from 321 water samples taken over three years at a large South African drinking water supplier. Using the data from raw water samples taken from a moderately turbid, large surface impoundment, as well as samples from the same water after treatment, typical ranges of the model parameters are presented for both raw and treated water. Once calibrated, the model allows the calculation and comparison of total particle number and volumes over any randomly selected size interval of interest. © 2009 Author(s).

Ramphal S.R.,Rand Water | Sibiya M.S.,Rand Water
Drinking Water Engineering and Science | Year: 2014

The size and structural characteristics of floc particles are important design and control parameters in water treatment and should be rapidly monitored with a reasonable amount of accuracy. In this study, a photometric dispersion analyser (PDA) coupled to standard jar test experiments was used to optimize coagulation-flocculation parameters while monitoring floc size and structure as well as the rate of floc formation during coagulation using alum. The optimal coagulation conditions were as follows: sample pH 8; alum dosage, 3 mg L1 as Al3+G value, 172 s1; rapid mixing time, 20 s. These conditions resulted in unstable treated water having a calcium carbonate precipitation potential (CCPP) of g15 mg L1 as CaCO3 and required a slaked lime dosage of 17 mg L1 as CaCO3 to equilibrate CCPP to acceptable levels. PDA data revealed that aggregation rate and steady-state variance are primary parameters as both have substantial influence on coagulation-flocculation efficiency. However, the average steady state ratio, although an important parameter, had a lessened impact on coagulation-flocculation efficiency. The results of this study showed that the PDA instrument is an important tool in coagulation kinetic studies and can be employed as an additional tool in the optimization of coagulation conditions. © 2014 Author(s).

Arendze S.,Rand Water | Sibiya M.,Rand Water
Journal of Water Reuse and Desalination | Year: 2014

Filtration acts as the final step in the removal of suspended matter and protozoa. The accumulated residue is removed during the backwash process and any subsequent recycling of filter backwash water could potentially re-introduce these contaminants into the main treatment process. By separating the filter backwash water from the main treatment process, factors that could interfere with the integrity of the primary treatment barriers, will be eliminated. Treatment and recovery of the filter backwash water would be beneficial in terms of water reuse, by replacing a proportion of the freshwater demand. The aim of this study was to investigate possible treatment options for the filter backwash water at Rand Water. Treatment options for filter backwash water treatment plants usually consist of a solids removal process and a disinfection process. Three solid removal processes for filter backwash water from Rand Water's filtration systems were selected for testing on an experimental basis: (1) sedimentation without flocculation, (2) sedimentation with flocculation, and (3) dissolved air flotation with flocculation. Flocculation with sedimentation produced the best results when compared to the other two treatment options evaluated. It is a simple and effective option for the treatment of filter backwash water. © IWA Publishing 2014.

Ngwenya N.,Rand Water | Ncube E.J.,Rand Water | Parsons J.,Rand Water
Reviews of Environmental Contamination and Toxicology | Year: 2013

The need for water disinfection in the developing world is undeniable. Disinfecting drinking water is critical for achieving an adequate level of removal or inactivation of pathogenic organisms that exist in raw water, for preventing recontamination of drinking water within the distribution system, and maintaining drinking water quality throughout the distribution system (USEPA 1999; AWWA 2001a; Sommer et al. 2008; WHO 2011). Waterborne diseases cause about five million human deaths per year, at least half of which are children (UNICEF 1995). Therefore, water utilities have the vital responsibility of managing water quality risks to ensure the safety and quality of water supplied to their customers. Since the beginning of the nineteenth century, inactivating and or removing pathogenic organisms (disinfection) from drinking water have been the main approaches to safeguard drinking water quality (Hrudey and Hrudey 2004). In the absence of drinking water disinfection, people are subject to falling ill from infectious diseases, caused by pathogenic bacteria, viruses, and protozoan parasites. © 2013 Springer Science+Business Media New York.

Mongalo M.,Rand Water | Sibiya M.,Rand Water | Skosana G.,Rand Water
14th Water Distribution Systems Analysis Conference 2012, WDSA 2012 | Year: 2012

Chlorine is a widely used disinfected in the world due to its disinfection ability to provide partial safe guard of water from disease causing pathogenic organisms. It is therefore important to maintain chlorine residual throughout the distribution system. In this paper a mathematical model that predicts the decay of chlorine in the Rand Water distribution system is presented. The results indicate that the nth order decay equation was able to predict for the chlorine decay for the distribution system. The decay constant varied between 0.2 - 0.38 h-1 and is directly proportional to the temperature of the water, while the reaction order varied between 1.9 - 2.6. The nth order decay model predicted chlorine decay at Rand Water more precisely in comparison with the other mathematical models tested. Copyright © (2012) by Engineers Australia.

Ncube E.J.,RSA Inc | Mohotsi M.,Rand Water
14th Water Distribution Systems Analysis Conference 2012, WDSA 2012 | Year: 2012

To maintain microbial quality, a distribution network should be designed and operated to prevent ingress of contaminants, to keep disinfectant residual concentrations within a locally predetermined range and to minimize the transit time (or age of the water after leaving the treatment works). With this in mind a study to determine the relationship between Standard Plate Counts (SPCs) and disinfectant residual in the distribution network was conducted. Data was extracted from an SQL database using Crystal reports application which is a business object tool. The statistics was calculated using the tool. The graphs were drawn using excel for simplicity purposes. This is used to identify relationships in the trend between the two parameters. The trend indicates some relationship between SPCs and chlorine in terms of compliance. The other parameters (E.coli, dissolved organic carbon (DOC) and turbidity were constantly in the region above 95% compliance except for chlorine, SPC and Total Coliforms (TCs). It was observed that a drop in the chlorine compliance results in a drop in SPC compliance. This is indicative of a relationship between the two parameters. However, this does not exclude any further impact that other parameters may have on this relationship. Copyright © (2012) by Engineers Australia.

Muzi Sibiya S.,Rand Water
Procedia Engineering | Year: 2014

A streaming current detector (SCD) is an instrument for measuring the charge that exists on small, suspended particles in water. The SCD is the instrument that can be used to measure coagulated particle stability for the feedback control of coagulant dosage. This report discusses the application of SCD as an instrument for coagulation dosage control. The SCD with automatic control of coagulant dosage consistently produced acceptable water quality, even during periods of changing raw water turbidity and varying flow rates. It minimizes under and overdosing of coagulant. It requires regular cleaning and maintenance to ensure optimum operation. The SCD is no substitute for efficient water treatment management. © 2013 The Authors.

Ramphal S.,Rand Water | Muzi Sibiya S.,Rand Water
Procedia Engineering | Year: 2014

Coagulation involves the rapid mixing of chemicals with raw water to facilitate particle destabilization. This study used a photometric dispersion analyzer (PDA) coupled to a jar stirrer to monitor kinetics during the optimization of alum. The optimal conditions were as follows: sample pH 8; alum dosage, 6 mg/l as Al3+; G-value, 116 s-1, rapid mixing time, 15 seconds. Kinetic data revealed that the aggregation rate and steady-state variance significantly influenced coagulation-flocculation performance; while average steady-state ratio displayed a minor influence on performance. The results indicated that the PDA instrument can be employed as an additional tool in the optimization of coagulation conditions. © 2013 The Authors. Published by Elsevier Ltd.

PubMed | Rand Water
Type: | Journal: Reviews of environmental contamination and toxicology | Year: 2012

Drinking water is the most important single source of human exposure to gastroenteric diseases, mainly as a result of the ingestion of microbial contaminated water. Waterborne microbial agents that pose a health risk to humans include enteropathogenic bacteria, viruses, and protozoa. Therefore, properly assessing whether these hazardous agents enter drinking water supplies, and if they do, whether they are disinfected adequately, are undoubtedly aspects critical to protecting public health. As new pathogens emerge, monitoring for relevant indicator microorganisms (e.g., process microbial indicators, fecal indicators, and index and model organisms) is crucial to ensuring drinking water safety. Another crucially important step to maintaining public health is implementing Water Safety Plans (WSPs), as is recommended by the current WHO Guidelines for Drinking Water Quality. Good WSPs include creating health-based targets that aim to reduce microbial risks and adverse health effects to which a population is exposed through drinking water. The use of disinfectants to inactivate microbial pathogens in drinking water has played a central role in reducing the incidence of waterborne diseases and is considered to be among the most successful interventions for preserving and promoting public health. Chlorine-based disinfectants are the most commonly used disinfectants and are cheap and easy to use. Free chlorine is an effective disinfectant for bacteria and viruses; however, it is not always effective against C. parvum and G. lamblia. Another limitation of using chlorination is that it produces disinfection by-products (DBPs), which pose potential health risks of their own. Currently, most drinking water regulations aggressively address DBP problems in public water distribution systems. The DBPs of most concern include the trihalomethanes (THMs), the haloacetic acids (HAAs), bromate, and chlorite. However, in the latest edition of the WHO Guidelines for Drinking Water Quality, it is recommended that water disinfection should never be compromised by attempting to control DBPs. The reason for this is that the risks of human illness and death from pathogens in drinking water are much greater than the risks from exposure to disinfectants and disinfection by-products. Nevertheless, if DBP levels exceed regulatory limits, strategies should focus on eliminating organic impurities that foster their formation, without compromising disinfection. As alternatives to chlorine, disinfectants such as chloramines, ozone, chlorine dioxide, and UV disinfection are gaining popularity. Chlorine and each of these disinfectants have individual advantage and disadvantage in terms of cost, efficacy-stability, ease of application, and nature of disinfectant by-products (DBPs). Based on efficiency, ozone is the most efficient disinfectant for inactivating bacteria, viruses, and protozoa. In contrast, chloramines are the least efficient and are not recommended for use as primary disinfectants. Chloramines are favored for secondary water disinfection, because they react more slowly than chlorine and are more persistent in distribution systems. In addition, chloramines produce lower DBP levels than does chlorine, although microbial activity in the distribution system may produce nitrate from monochloramine, when it is used as a residual disinfectant, Achieving the required levels of water quality, particularly microbial inactivation levels, while minimizing DBP formation requires the application of proper risk and disinfection management protocols. In addition, the failure of conventional treatment processes to eliminate critical waterborne pathogens in drinking water demand that improved and/or new disinfection technologies be developed. Recent research has disclosed that nanotechnology may offer solutions in this area, through the use of nanosorbents, nanocatalysts, bioactive nanoparticles, nanostructured catalytic membranes, and nanoparticle-enhanced filtration.

Loading Rand Water collaborators
Loading Rand Water collaborators