-
The Role of Executive Function in Bridging the Intention-Behaviour Gap for Binge-Drinking in University Students
04 June 2012University of SydneyMullan, Barbara;Wong, Cara;Allom, Vanessa;Pack, SophiaBackground Alcohol consumption contributes to a significant proportion of disease and the high prevalence amongst young adults is a worldwide health concern. Purpose To determine which aspects of executive function (EF) distinguish binge-drinkers from non binge-drinkers and to establish the role of EF in predicting behaviour. Methods Self-report questionnaires, four tests of self-regulation and a behaviour measure were administered to 153 students. Results The Theory of Planned Behaviour model was significant in predicting both intentions and behaviour. Although binge-drinkers and non binge-drinkers were found to differ on three of the four measures of EF, none predicted additional variance in behaviour. Planning ability and inhibition control moderated the relationship between intention and behaviour such that for individuals who intended to binge-drink, those with high planning ability or high inhibitory control were more likely to avoid doing so. Conclusions Interventions targeting binge-drinking behaviour should aim to develop planning skills and inhibitory control.
-
Household water efficiency strategies in Cornwall, SW of England
11 October 2016University of SydneySharpe, Richard A.;Osborne, Nicholas J.;Skerratt, GlynnDemand-side measures are thought to be a sustainable approach to meeting the future supply-demand balance. We assess the uptake of domestic demand-side measures and potential factors that may promote the uptake of water efficiency devices. Fifty-one face-to-face questionnaires were used to collect demographic and household characteristics data. We use descriptive statistics and univariate models to assess factors promoting water efficiency. Fifty-one adult participants aged between 30 and 64 years provided data on water consumption and efficiency. Participants investigating water saving solutions and homeowners were more likely to utilise water efficiency devices. Targeted factors shown to promote consumer up-take of water efficiency measures along with strategies utilising low-cost efficiency devices provide a cost-effective means to reduce water consumption.
-
Communicating about risk: strategies for situations where public concern is high but the risk is low.
15 February 2017University of SydneyHooker, C;Capon, A;Leask, JIn this article, we summarise research that identifies best practice for communicating about hazards where the risk is low but public concern is high. We apply Peter Sandman’s ‘risk = hazard + outrage’ formulation to these risks, and review factors associated with the amplification of risk signals. We discuss the structures that determine the success of risk communication strategies, such as the capacity for early communication to ‘capture’ the dominant representation of risk issues, the importance of communicating uncertainty, and the usefulness of engaging with communities. We argue that, when facing trade-offs in probable outcomes from communication, it is always best to choose strategies that maintain or build trust, even at the cost of initial overreactions. We discuss these features of successful risk communication in relation to a range of specific examples, particularly opposition to community water fluoridation, Ebola, and routine childhood immunisation.
-
Expectancy in double-blind placebo-controlled trials: An example from alcohol dependence
17 January 2019University of SydneyColagiuri, Ben;Morley, Kirsten;Boakes, Robert A;Haber, PaulBackground: Double-blind placebo-controlled trials are intended to control for the impact of expectancy on outcomes. Whether they always achieve this is, however, questionable. Methods: Reanalysis of a clinical trial of naltrexone and acamprosate for alcohol dependence investigated this issue further. In this trial, 169 alcohol dependent patients received naltrexone, acamprosate, or placebo for 12 weeks. In addition to being assessed on various indices of alcohol dependence, they were asked whether they believed they received active medication or placebo. Results: While there were no differences in outcomes between treatment groups, those who believed they had been taking active medication consumed fewer alcoholic drinks and reported less alcohol dependence and cravings. That is, irrespective of actual treatment, perceived medication allocation predicted health outcomes. Conclusions: These results highlight the differences between treatment administration in clinical trials and standard medical practice, a discrepancy that may sometimes decrease the validity of these types of trials
-
Pain From Bluebottle Jellyfish Stings
26 May 2020University of SydneyLi, Li;McGee, Richard G;Webster, Angela CAn 11‐year‐old girl presented to the emergency department with severe pain after a jellyfish sting at a New South Wales beach. Bluebottle (Physalia) jellyfish was deemed the most likely cause considering her geographical location. The Australian Resuscitation Council Guideline (2010) suggests immersing in water as hot as can be tolerated for 20 min for treating pain from jellyfish stings. This guideline was written based on past case reports, books and randomised controlled trials (RCTs). We performed a search to assess the most current evidence for relief of pain from Bluebottle jellyfish stings, which yielded two systematic reviews and seven RCT s. Both systematic reviews had similar conclusions, with one of the RCT s used in both reviews showing the most relevance to our presenting patient in terms of demographics, location and jellyfish type. This journal club article is an appraisal of this RCT by Loten et al . and the validity of its conclusion that hot water immersion is most effective for the relief of pain from Bluebottle stings.
-
A longitudinal study of the influence of comorbidities and lifestyle factors on low back pain in older men
11 June 2020University of SydneyParreira, P;Maher, C;Ferreira, M;Machado, G;Blyth, F;Naganathan, V;Waite, L;Seibel, M;Handelsmann, D;Cumming, ROlder adults are largely under-represented in low back pain (LBP) research. In light of the ageing population, it is crucial to understand the influence of comorbidities and lifestyle factors on the risk and prognosis of LBP in older adults. The aims of this study were to describe the course of LBP in older men; to investigate whether comorbidities/lifestyle factors can predict the course of LBP in older men; to assess if comorbidities/lifestyle factors increase the risk of developing LBP in older men. The study sample comprised 1685 older men living in suburban Sydney, Australia. Low back pain, sociodemographic measures, lifestyle factors, and comorbidities were assessed. Of the 1012 men with LBP at baseline, 58% still reported having pain at the 24-month follow-up. Of those without pain at baseline (n = 673), 28% reported pain at follow-up. The odds of persistent pain at 24 months increased with each additional alcoholic drink/wk (odds ratio [OR] = 1.10, 95% confidence interval [CI]: 1.01-1.22; P = 0.03) and each additional unit of body mass index (OR = 1.28, 95% CI: 1.04-1.60; P = 0.02), but reduced for men who speak English at home (OR = 0.58, 95% CI: 0.35-0.96; P = 0.03). In older men, free of LBP at baseline (n = 673), for every additional comorbidity there was an increased risk of developing LBP (OR = 1.17, 95% CI: 1.00-1.37; P = 0.05). These results demonstrate the influence of lifestyle factors and comorbidities on LBP in older men and suggest that the consideration of these issues in management may improve outcomes.
-
Location and primary health care reform
09 July 2020University of SydneyC, Gemma;Ward, Jeanette EA fresh examination of potential preventable hospitalisation rates gives new insights and strategic direction
-
Health risks, preventive behaviours and respiratory illnesses at the 2019 arbaeen: Implications for covid-19 and other pandemics
06 April 2021University of SydneyAl-Ansari, F.;Mirzaei, M.;Al-Ansari, B.;Al-Ansari, M.B.;Abdulzahra, M.S.;Rashid, H.;Hill-Cawthorne, G.A.;Ansari, M.A.;Negin, J.;Conigrave, K.COVID-19 poses grave challenges for mass gatherings. One of the world's largest annual gatherings, Arbaeen, occurs in Iraq. We studied respiratory symptoms and risk and protective factors using representative sampling of Arbaeen pilgrims in 2019 to inform prevention of COVID-19 transmission. Structured sampling was used to recruit walking pilgrims. A questionnaire asked about respiratory symptoms, risk, and preventive factors, including hygiene-related resources of toilet facilities. The commonest symptom reported by the 1842 participants (63.3% male, 36.7% fe-male) was cough (25.6%). Eating in mawkibs (rest areas) with indoor kitchens and drinking only packaged water were associated with lower risk of cough (AOR = 0.72, CI = 0.56-0.94; AOR = 0.60; CI = 0.45-0.78, p < 0.05). Facemask use was associated with increased risk of cough (AOR = 2.71, CI = 2.08-3.53, p < 0.05). Handwashing was not protective against cough, or against (one or more of) cough, fever, or breathlessness in multivariate analysis. Toilet facilities often lacked running water (32.1%) and soap (26.1%), and had shared hand towels (17%). To reduce risk of respiratory infections including COVID-19 during Arbaeen or other mass gatherings, needs include running water, soap, and hygienic hand drying options or hand sanitiser. Education on proper handwashing and facemask approaches and monitoring around food preparation and eating spaces are needed.
-
An Observational Assessment of Australian Apple Production Practices for Microbial Control
07 April 2021University of SydneyFrankish, Elizabeth J.;Bozkurt, Hayriye;Ross, Thomas;Phan-Thien, Kim-Yen;Luning, Pieternel A.;Bell, Tina L.;McConchie, RobynFood safety management criteria are often described in general terms rather than specific actions and potentially introduces subjectivity to interpretation and implementation. In the tree fruit sector, management systems would be more useful if developed with specific reference to production and processing practices used. There is insufficient evidence that requirements for the Australian tree fruit industry are appropriate to control foodborne pathogen contamination of ready-to-eat products. Thus, the purpose of this study was to explore industry interpretations of food safety guidelines by describing the application of controls in Australian orchards and packhouses and to evaluate production practices by characterising potential microbial risks in the apple industry, quantifying microbial load in wash water and fruit, and assessing fruit quality as indicators. Thirteen orchards and packhouses across Australia were visited from July 2016 to April 2018 to observe apple orchard practices, packhouse systems, wash water controls, general hygiene and to evaluate the presence of Escherichia coli, Salmonella spp. and Listeria spp. on multiple apple cultivars. The assessment revealed that the inconsistent application of water sanitation resulted in variable control of wash water quality and hygiene, but the prevalence of pathogens on apples was less than 2%. Variation in practices could increase the risk of foodborne illness to consumers if contamination occurs. The Australian apple industry could benefit from a better understanding of effective risk mitigation strategies, consistent industry application of food safety controls and improved evidence of controls achieving desired food safety outcomes.
-
COVID-19, indigenous peoples, local communities and natural resource governance
02 June 2021University of SydneyWalters, G.;Broome, N.P.;Cracco, M.;Dash, T.;Dudley, N.;El�as, S.;Hymas, O.;Mangubhai, S.;Mohan, V.;Niederberger, T.;Kema, C.A.N.-K.;Lio, A.O.;Raveloson, N.;Rubis, J.;Toviehou, S.A.R.M.;Vliet, N.V.We report on how the COVID-19 pandemic is affecting Indigenous peoples and local communities (IPLCs), especially those who govern, manage and conserve their lands and waters. We explore the themes of access and use of natural resources, solidarity, decision-making, the role of governments and IPLCs in managing COVID-19, and the uptake of traditional medicine. These themes are explored through a global online survey in English, Spanish and French. We collected and analysed 133 surveys from 40 countries, using SenseMaker®, a software that enables analysis of micronarratives based on how respondents classify their own stories. We explore the themes further through case studies from Benin, Fiji, France, Gabon, Guyana, Guatemala, India and Madagascar, highlighting challenges and opportunities in how IPLCs responded to COVID-19. Our study underscores the importance of self-empowerment and recognition of IPLC rights, which allows them to use traditional medicines, meet subsistence requirements during lockdowns, help community members and neighbours to sustain livelihoods, and to govern, defend and conserve their territories. We propose key actions to support IPLCs navigate future pandemics while protecting their lands and waters.
-
Community perspectives on the covid-19 response, zimbabwe [Perspectives communautaires dans la lutte contre la covid-19 au zimbabwe] [Opiniones de la comunidad sobre la respuesta a la covid-19, zimbabue]
02 June 2021University of SydneyMackworth-Young, C.R.S.;Chingono, R.;Mavodza, C.;McHugh, G.;Tembo, M.;Chikwari, C.D.;Weiss, H.A.;Rusakaniko, S.;Ruzario, S.;Bernays, S.;Ferrand, R.A.Objective To investigate community and health-care workers' perspectives on the coronavirus disease 2019 (COVID-19) pandemic and on early pandemic responses during the first 2 weeks of national lockdown in Zimbabwe. Methods Rapid qualitative research was carried out between March and April 2020 via phone interviews with one representative from each of four community-based organizations and 16 health-care workers involved in a trial of community-based services for young people. In addition, information on COVID-19 was collected from social media platforms, news outlets and government announcements. Data were analysed thematically. Findings Four themes emerged: (i) individuals were overloaded with information but lacked trusted sources, which resulted in widespread fear and unanswered questions; (ii) communities had limited ability to comply with prevention measures, such as social distancing, because access to long-term food supplies and water at home was limited and because income had to be earned daily; (iii) health-care workers perceived themselves to be vulnerable and undervalued because of a shortage of personal protective equipment and inadequate pay; and (iv) other health conditions were sidelined because resources were redirected, with potentially wide-reaching implications. Conclusion It is important that prevention measures against COVID-19 are appropriate for the local context. In Zimbabwe, communities require support with basic needs and access to reliable information to enable them to follow prevention measures. In addition, health-care workers urgently need personal protective equipment and adequate salaries. Essential health-care services and medications for conditions other than COVID-19 must also continue to be provided to help reduce excess mortality and morbidity.
-
Psychological Consequences of the Flint Water Crisis: A Scoping Review
10 June 2021University of SydneyBrooks, S.K.;Patel, S.S.Objective: To summarize existing literature on the mental health impact of the Flint Water Crisis. Methods: In March 2020, we searched 5 databases for literature exploring the psychological consequences of the crisis. Main findings were extracted. Results: 32 citations were screened and 11 included in the review. Results suggest a negative psychological effect caused by the water crisis, including anxiety and health worries, exacerbated by lowered trust in public health officials, uncertainty about the long-term impacts of the crisis, financial hardships, stigma, and difficulties seeking help. There was evidence that concerns about tap water continued even after the state of emergency was lifted. Conclusions: With a possible compound effect to residents of Flint with the recent COVID-19 pandemic, the results highlight the need for more resources for psychological health interventions in Flint as well as a need for local governments and health authorities to regain the trust of those affected by the Flint Water Crisis.
-
Ethics Guidance for Environmental Scientists Engaged in Surveillance of Wastewater for SARS-CoV-2.
06 July 2021University of SydneyHrudey, Steve E;Silva, Diego S;Shelley, Jacob;Pons, Wendy;Isaac-Renton, Judy;Chik, Alex Ho-Shing;Conant, BernadetteThe COVID-19 pandemic has given rise to rapid and widespread international pursuit of wastewater surveillance for genetic signals of SARS-CoV-2, the virus causing the pandemic. Environmental scientists and engineers familiar with the techniques required for this endeavor have responded. Many of the environmental scientists engaged in these investigations have not necessarily had experience with the ethical obligations associated with generating and handling human health data. The Canadian Water Network facilitated adoption of these surveillance methods by creating a national coalition, which included a public health advisory group that recognized a need for ethics guidance for the wastewater approach to public health surveillance. This Policy Analysis addresses that need and is based on a review of relevant ethics literature tightly focused on ethics applicable to public health surveillance. That review revealed that classical health bioethics governing clinical practice and general public health ethics guidance did not adequately address key issues in wastewater surveillance. The 2017 World Health Organization guidelines, directly based on a systematic literature review, specifically addressed ethical issues in public health surveillance. The application of relevant ethical guidance to wastewater surveillance is analyzed and summarized for environmental scientists.
-
2D materials and its heterostructured photocatalysts: Synthesis, properties, functionalization and applications in environmental remediation
19 October 2021University of SydneyGarg, Anushka;Basu, Soumen;Shetti, Nagaraj P.;Reddy, Kakarla RaghavaThe pharmaceuticals and organic dyes form a large group of contaminants contributing to depleting the water quality and posing a threat to both flora and fauna. These contaminants are generally released from textile and other industrial processes. The recent spread of Covid-19 worldwide has encouraged the infected population to intake antibiotics and antivirals for their recovery as well as a non-infected group to boost their immunity and prevent the spread. As the intake rate increases, the release of eliminated pharmaceuticals into the water bodies increases. Therefore, several techniques have been developed for the efficient degradation of pharmaceuticals in water. In this review, a detailed contribution of different researchers and scientists for the efficient removal of several antibiotics such as chloramphenicol, chlortetracycline, ciprofloxacin, tylosin, etc. is explained. Various routes for both human and veterinary medicines have been explained in detail. An exhaustive collection of bibliographical data has been done with articles in respective domains. Two dimensional (2D) materials and their composites due to their magnificent properties have been in the limelight for ages and have been exploited for potential applications in different areas such as sensing, drug delivery, batteries, and most importantly wastewater treatment. Several techniques with the help of different 2D composites such as photocatalysis, visible light degradation, electrocatalysis, dielectric barrier discharge system, and sonocatalysis have been emphasized to gain knowledge about the current trend and future prospects.
-
Ethnicity and media: a study of English and non-English language print media coverage of water issues in Sydney
28 October 2021University of SydneyYan, Liping;McManus, Phil;Duncan, ElizabethIt is critical to understand how matters relating to water are reported, or ignored, among linguistically diverse media and to understand the possible influence this may have on the conception of water issues among ethnically diverse groups. This research analysed five daily newspapers published in Sydney between 2011 and 2012 in three languages (English, Chinese and Korean) and found that water issues were presented differently by newspapers across language divides in Sydney. These differences may contribute to diverse conceptual constructions of water problems and water management among ethnically diverse communities. After allowing for the influence of other variables, this research highlights the necessity to investigate media construction of water issues in various Non-English language publications as an important approach to improving situated and place-based water awareness in an ethnically diverse city.
-
Indigenous Australian drinking patterns
01 December 2021University of SydneyZheng, Catherine;Conigrave, James;Conigrave, Katherine;Wilson, Scott;Perry, Jimmy;Chikritzhs, Tanya;Fitts, Michelle;Lee, K S KylieBackground Measuring self-reported alcohol use is challenging in any population, including when episodic drinking may be common. Drinking among Indigenous Australians has been shown to vary greatly within and between communities. However, most survey methods assume ‘regular’ patterns of drinking. National estimates have also been shown to underestimate alcohol use among this group. This paper describes drinking patterns in two representative community samples (urban and remote). Methods Indigenous Australians (aged 16+ years) in two South Australian sites were recruited to complete the Grog Survey App. The App is a validated, interactive tablet-based survey tool, designed to help Indigenous Australians describe their drinking. Drinking patterns were described using medians and interquartile ranges; gender and remoteness were compared using Wilcoxon rank-sum tests. Spearman correlations explored the relationship between drinking patterns and age. Logistic regressions tested if beverage or container preference differed by remoteness or gender. Results Three-quarters of participants (77.0%, n=597/775) were current drinkers. Median standard drinks quarters of current drinkers (73.7%) reported a period without drinking (median: 60 days). Remote drinkers were more likely to drink beer. Improvised containers were used by 40.5% of drinkers. Conclusions Episodic drinking with extended ‘dry’ periods and from non-standard drinking containers was common in this representative sample of Indigenous Australians. The diversity of container use and beverage preference, by gender and remoteness, illustrates nuances in drinking patterns between communities. It shows the importance of community-level data to inform local strategies addressing alcohol misuse.
-
Correlations for maximum penetration heights of transitional plane fountains in linearly stratified fluids
20 December 2021University of SydneyInam, Mohammad;Lin, WenxianIn this study, a series of three-dimensional direct numerical simulations (DNS) were carried out using ANSYS Fluent for transitional plane fountains in linearly stratified fluids with the Reynolds number (Re), Froude number (Fr) and dimensionless temperature stratification parameter (s) over 28 ≤ Re ≤ 300, 3 ≤ Fr ≤ 10, and 0.1 ≤ s ≤ 0.5, to study and quantify the effects of these governing parameters on the maximum fountain penetration height, including the initial one during the early developing stage and the time-averaged one at the quasi-steady state, as well as the time to reach the initial maximum penetration height. The results show that both the initial and time-averaged maximum fountain heights as well as the time to attain the initial maximum fountain height increase with Fr but decrease with s, whereas the effect of Re is negligible, and the fluctuations of the maximum fountain penetration height at some specific locations at the quasi-steady state also follow the similar trends. Empirical correlations to quantify the effects of Fr, s and Re on these bulk fountain behavior parameters were obtained from the DNS results over the ranges of Fr, s and Re considered.
-
Interaction behavior of triple transitional round fountains in a homogeneous fluid
20 December 2021University of SydneyMahmud, Hasan;Lin, Wenxian;Gao, Wenfeng;Armfield, Steven;He, YingheIn this study, the PIV and flow visualization techniques and three-dimensional di- rect numerical simulation are used to investigate the behavior of triple transitional round fountains, which are aligned along a straight line, interacting with each other in a homo- geneous fluid over the ranges of 1 ≤ Fr ≤ 10 and 100 ≤ Re ≤ 1000, at a fixed spacing of D/X0 = 6, where Re and F r are the Reynolds and Froude numbers, D is the spacing between the two neighbouring fountain sources, and X0 is the radius of orifices at the fountain source, respectively. The results show that the interaction behavior of triple transitional round fountains, over the ranges of Re and Fr studied, is dominated by the bobbing and flapping motions, and is either steady, or unsteady weakly multi-modal, or unsteady strongly multi-modal. In a steady interaction, the bobbing-flapping motions are only present in its initial development stage and the interaction will attain a steady state in the later stage in which the bobbing-flapping motions are no longer present. In contrast, in an unsteady interaction, the interaction remains unsteady all the time and the bobbing-flapping motions are present at all stages. Among all cases considered, a steady interaction occurs at Re ≤ 300 with Fr = 1 and at Re = 100 with Fr ≤ 5; an unsteady weakly multi-modal interaction occurs at Re = 100 with 6 ≤ F r ≤ 10, at 200 ≤ Re ≤ 300 with 2 ≤ Fr ≤ 10, and at Re = 400 with Fr = 1; and an unsteady strongly multi-modal interaction occurs at 600 ≤ Re ≤ 1000 with Fr = 1 and at 400 ≤ Re ≤ 1000 with2 ≤ F r ≤ 10. Such interaction behavior is found to be similar to that of twin transitional round fountains over comparable ranges of Re and Fr, as discovered by us in an earlier study. It is also found that the two interaction regions formed by the three fountains have essentially symmetrical behavior about the middle fountain for all cases considered. Furthermore, the maximum fountain penetration heights and the maximum thicknesses of the interaction regions of the triple transitional round fountains are quantified with the experimental and numerical results and compared to the available scalings for single fountains at comparable Fr and Re values. Several scaling relations are then developed for these parameters over the ranges of Fr and Re considered.
-
Drinking risk varies within and between Australian Aboriginal and Torres Strait Islander samples: a meta-analysis to identify sources of heterogeneity
22 December 2021University of SydneyConigrave, James;Lee, Kylie;Zheng, Catherine;Wilson, Scott;Perry, Jimmy;Chikritzhs, Tanya;Slade, Tim;Morley, Kirsten;Room, Robin;Callinan, Sarah;Hayman, Noel;Conigrave, KatherineBackground and Aims To reduce health and social inequities, it is important to understand how drinking patterns vary within and between Indigenous peoples. We aimed to assess variability in estimates of Indigenous Australian drinking patterns and to identify demographic and methodological factors associated with this. Design A three-level meta-analysis of Australian Aboriginal and Torres Strait Islander (‘Indigenous’) drinking patterns [International Prospective Register of Systematic Reviews (PROSPERO) no. CRD42018103209]. Setting Australia. Participants Indigenous Australians. Measurements The primary outcomes extracted were drinking status, single-occasion risk and life-time risk. Moderation analysis was performed to identify potential sources of heterogeneity. Moderators included gender, age, socio-economic status, local alcohol restrictions, sample population, remoteness, Australian state or territory, publication year, Indigenous involvement in survey design or delivery and cultural adaptations. Findings A systematic review of the literature revealed 41 eligible studies. For all primary outcomes, considerable heterogeneity was identified within ( urn:x-wiley:09652140:media:add15015:add15015-math-0001 = 51.39–68.80%) and between ( urn:x-wiley:09652140:media:add15015:add15015-math-0002 = 29.27–47.36%) samples. The pooled proportions (P) of current drinkers [P = 0.59, 95% confidence interval (CI) = 0.53–0.65], single-occasion (P = 0.34, 95% CI = 0.24–0.44) and life-time (P = 0.21, 95% CI = 0.15–0.29) risk were all moderated by gender, age, remoteness and measurement tool. Reference period moderated proportions of participants at single-occasion risk. Conclusions Indigenous Australian drinking patterns vary within and between communities. Initiatives to reduce high-risk drinking should take account of this variability.
-
Patterns of drinking in Aboriginal and Torres Strait Islander peoples as self-reported on the Grog Survey App: A representative urban and remote sample
22 December 2021University of SydneyZheng, Catherine;Conigrave, James;Conigrave, Katherine;Wilson, Scott;Perry, Jimmy;Chikritzhs, Tanya;Fitts, Michelle;Lee, KylieIntroduction: Measuring self-reported alcohol use is challenging in any population, including when episodic drinking may be common. Drinking among Indigenous Australians has been shown to vary greatly within and between communities. However, most survey methods assume 'regular' patterns of drinking. National estimates have also been shown to underestimate alcohol use among this group. This paper describes drinking patterns in two representative community samples (urban and remote). Methods: Indigenous Australians (aged 16+ years) in two South Australian sites were recruited to complete the Grog Survey App. The App is a validated, interactive tablet-based survey tool, designed to help Indigenous Australians describe their drinking. Drinking patterns were described using medians and interquartile ranges; gender and remoteness were compared using Wilcoxon rank-sum tests. Spearman correlations explored the relationship between drinking patterns and age. Logistic regressions tested if beverage or container preference differed by remoteness or gender. Results: Three-quarters of participants (77.0%, n = 597/775) were current drinkers. Median standard drinks per occasion was 7.8 (78 g), 1.3 drinking occasions per month (median). Three-quarters of current drinkers (73.7%) reported a period without drinking (median: 60 days). Remote drinkers were more likely to drink beer. Improvised containers were used by 40.5% of drinkers. Discussion and conclusions: Episodic drinking with extended 'dry' periods and from non-standard drinking containers was common in this representative sample of Indigenous Australians. The diversity of container use and beverage preference, by gender and remoteness, illustrates nuances in drinking patterns between communities. It shows the importance of community-level data to inform local strategies addressing alcohol misuse.
-
The new humanitarian crisis in Ukraine: Coping with the public health impact of hybrid warfare, mass migration, and mental health trauma.
28 April 2022University of SydneyPatel, Sonny S;Erickson, Timothy BOne of the largest mass movements of displaced people from their homelands in recent history must be recognized and assisted by the Free World. The unprovoked Russian attacks on Ukraine during February-March 2022 will leave long-lasting devastating effects on millions of innocent victims. Nations worldwide, especially NATO member countries, will need to intervene to ameliorate the situation. This letter describes major public health issues apart from the COVID-19 pandemic that are emerging concerns, such as shortages of healthcare professionals, chronic care treatments and health prevention services, disinformation communication campaigns affecting the healthcare infrastructure, and the generational impact of the conflict on people's mental health. A global response and public health support need immediate action including humanitarian assistance, food security, clean water supplies, adequate shelter, and safe transportation out of the active military zones.
-
Molecular Monitoring of SARS-CoV‑2 in Different Sewage Plants in Venice and the Implications for Genetic Surveillance
04 July 2022University of SydneyBrian, Irene;Manuzzi, Alice;Rovere, Giulia Dalla;Giussani, Edoardo;Palumbo, Elisa;Fusaro, Alice;Bonfante, Francesco;Bortolami, Alessio;Quaranta, Erika Giorgia;Monne, Isabella;Patarnello, Tomaso;Bargelloni, Luca;Terregino, Calogero;Holmes, Edward C.;Todesco, Giovanna;Sorrentino, Francesco;Berton, Andrea;Badetti, Christian;Carrer, Claudio;Ferrari, Giorgio;Zincone, Cinzia;Milan, Massimo;Panzarin, ValentinaThe analysis of different samples from the purification lines in WWTPs provides valuable data on SARS-CoV-2 prevalence, the predominant variants, and decontamination efficacy.
-
Variability in practices for drinking water vaccination of meat chickens against infectious laryngotracheitis
27 September 2022University of SydneyGroves, Peter J.;Assen, Awol M.;Etherington, Ashley;Stillman, Mark;Alfirevich, Sheridan;Gerber, Priscilla F.;Langfield, Alex-Kate;Walkden-Brown, Stephen W.Context: Drinking water vaccination of young meat chickens with Infectious Laryngotracheitis (ILT) vaccine is problematic. Vaccine failure and adverse vaccine reactions are frequently reported. Variations in the technique of applying ILT vaccines by this mass vaccination method need to be understood to contribute to improving the success of vaccination. Aims: This study aimed to examine variations in the techniques of application of Infectious Laryngotracheitis vaccines via drinking water for young meat chickens. Methods: Drinking water vaccination techniques were observed and recorded across 52 broiler flocks during ILT outbreaks in three geographic areas of Australia. Descriptive statistics for all variables were computed and variations between integrator company procedures were statistically compared. Key results: Despite rigorous standard operating procedures, wide variations were observed in time of water deprivation prior to vaccination (3–15 min), time drinking water was stabilised prior to addition of vaccine and the type of stabiliser product used, time to activate the flock following filling of the water lines with vaccine (10–127 min), time for the vaccine to be consumed (36–226 min) and the volume of drinking water per bird used to provide the vaccine (11–48 mL/bird). Conclusions: Variation in vaccination technique can affect the success of drinking water vaccination against ILT in young meat chickens. Implications: Understanding the importance of the variable factors in vaccine application method can improve the success of water vaccination against ILT.
-
The roles of metal-organic frameworks in modulating water permeability of graphene oxide-based carbon membranes
21 December 2022University of SydneySui, Xiao;Ding, Hongru;Yuan, Ziwen;Leong, Chanel F.;Goh, Kunli;Li, Wei;Yang, Nuo;D'Alessandro, Deanna M.;Chen, YuanGraphene oxide (GO) can be processed into carbon membranes with unique water permeability and molecular selectivity. Metal-organic frameworks (MOFs) have been proposed as filler materials to enhance water permeability of laminar GO-based carbon membranes. However, it remains unclear how the enhancement arises. Herein, we combined experimental and molecular simulation studies to provide critical insights into the water transport behaviors of GO/MOF composite membranes. The water permeability enhancement was found to be directly correlated to the increase in the average interlayer spacing between GO nanosheets. The simulation results indicate a slower water transport through nanochannels in MOFs than in nanochannels formed by GO nanosheets. A small amount of MOF particles only serves as a blockage in laminar GO membranes, suppressing their water permeability. In contrast, a large amount of MOF particles increases the interlayer spacing between GO nanosheets and creates very fast water transport stretches. Besides, some large gaps are formed between non-smooth MOF particles and GO nanosheets, adding supplementary water channels to deliver higher water permeability. We envision a shift in future research direction to exploit the selective adsorption capacity of MOFs other than leveraging them as fast water transport channels to realize their potential water treatment applications.
-
Don't Go in the Water: On Pathological Jurisdiction Splitting
01 January 2020University of PennsylvaniaColburn, Jamison E.Waters and water rights have endured (or induced) a uniquely pathological tendency in our tradition to split up the authority to declare the operative legal interests therein. By studying three seemingly unrelated areas of waters and water rights law, this tendency is brought out in its essence and linked to explicit foundations and likely causes. Ultimately, this kind of extreme jurisdiction splitting is rendering our waters ungovernable, forcing even the most basic legal questions to go undecided. The last part of the article introduces three different reform pathways but cautions against the search for quick fixes of any kind.
-
Come Hell or High-Water: Challenges for Adapting Pacific Northwest Water Law
01 January 2020University of PennsylvaniaFowler, Lara;Caccese, Robert T.The Pacific Northwest region of the United States has been recognized as a leader in crafting water laws that work to balance human needs and ecological considerations. However, this region is experiencing changing dynamics that test the strength of existing water policies and laws. Such dynamics include increasing populations, new and exempt uses, quantification of tribal treaty rights, species protection, renegotiation of the Columbia River Treaty, and the impacts of a changing climate. Together, these dynamics are stressing the legal framework, which remains vital to ensuring sustainable water supplies now and into the future. The history behind water resources management in Oregon, Washing- ton, Idaho, and Montana provides the foundation for the laws in place today. Although all four states share regulatory features, nuances specific to each state have tremendously affected their governance structures and ability to adapt to changing dynamics. Although a challenge to meet these changing dynamics, collaborative efforts offer creative opportunities for meeting current and future needs.
-
Implementing a New Data Model for Simulating Processes
15 May 2006University of EdinburghReitsma, Femke;Albrecht, JochenThe paper describes the development of a new methodological approach for simulating geographic processes through the development of a data model that represents a process. This methodology complements existing approaches to dynamic modelling, which focus on the states of the system at each time step, by storing and representing the processes that are implicit in the model. The data model, called nen, focuses existing modelling approaches on representing and storing process information, which provides advantages for querying and analyzing processes. The flux simulation framework was created utilizing the nen data model to represent processes. This simulator includes basic classes for developing a domain specific simulation and a set of query tools for inquiring after the results of a simulation. The methodology is prototyped with a watershed runoff simulation.
-
Fouling in greywater recycling by direct ultrafiltration
01 November 2010University of EdinburghNghiem, Long D.;Oschmann, Nadine;Schäfer, AndreaGreywater is no doubt a valuable resource that can be used to alleviate water shortage and increase water conservation in individual households. It is particularly important for arid and semiarid regions like Australia. Treated greywater can also be used for many activities within the household such as toilet flushing, garden watering, car washing, or pavement cleansing. This study examines the fouling behaviour of submerged ultrafiltration membranes in greywater recycling under concentration variation of common greywater constituents. The results indicate that the use of ultrafiltration directly for greywater recycling in individual households is promising. As expected, increase in particulate matter concentration results in a thicker cake layer. However, hydraulic resistance of such cake layers depends on the presence of other constituents namely calcium and organic matter, which play a major role in membrane fouling. Fouling increases linearly with organic matter concentration, while the presence of a small amount of calcium may enhance fouling significantly.
-
Relevance of the precautionary principle in water recycling
01 November 2010University of EdinburghSchäfer, Andrea;Beder, SIn an engineering context the precautionary principle is often perceived as an excuse to do nothing or a substantial barrier to technical progress. The precautionary principle requires that remedial measures be taken in situations of scientific uncertainty where evidence of harm cannot be proven but potential damage to human or environmental health is significant. In this paper the scope of the precautionary principle in water recycling is discussed. It is clear that uncertainties and risks exist in many areas of water recycling. Those risks are closely linked to the risks of sewage discharge. Hence water recycling has two main areas of concern (i) the dilemma that minimising potential environmental harm by reducing effluent discharge may increase potential harm through reducing the water flow in receiving waters and (ii) the consequences of using recycled water of varying quality for a number of applications. The precautionary principle can be regarded as an opportunity to improve water recycling practice and in fact increase the scope of ecologically sustainable water recycling. Hence the precautionary principle has an important role to play as a guide in decision making and in dealing with the vast number of risks and uncertainties in water recycling.
-
Fouling autopsy of hollow-fibre MF membranes in wastewater reclamation
01 November 2010University of EdinburghNghiem, Long D.;Schäfer, AndreaFouling in membrane filtration processes is problematic but inevitable as it occurs with the retention of contaminants that accumulate on the membrane surface. The causes of fouling are often specific, depending upon feed water constituents, the membrane, and the operation regime. Therefore, it is desirable that a thorough investigation is performed on fouled membrane elements of the affected plant. This technique is known as “membrane autopsy”, which identifies the cause of poor membrane performance, and hence, gives the opportunity to rectify or mitigate the problem and improve future plant design. The cause of membrane fouling at a small water recycling plant using a hollow-fibre microfiltration system was investigated. A membrane autopsy protocol was developed for water recycling applications that consists of four major steps: (1) tensile testing to investigate the membrane mechanical integrity, (2) direct visual inspection, (3) membrane surface analysis using field-emission environmental scanning electron microscopy (as well as atomic force microscopy, although it is not used in this case) techniques, and (4) foulant constituent analysis. Results obtained from this study indicate that the membrane was fouled by a mixture of colloids and organic matters, enhanced by the presence of multivalent cations. Possible measures to mitigate fouling in this particular case have also been suggested.
-
Desalination using electrodialysis as a function of voltage and salt concentration
01 November 2010University of EdinburghBanasiak, Laura J.;Kruttschnitt, Thomas W.;Schäfer, AndreaElectrodialysis is a process that competes with reverse osmosis for desalination and the removal of specific inorganic contaminants. Desalination experiments were carried out on aqueous solutions containing 5 and 10 g/L NaCl to determine the optimum operating conditions of an electrodialysis (ED) system. Further desalination of aqueous solutions containing 1, 5, 10, 20, 25 and 35 g/L NaCl at an optimum applied voltage of 12 V was conducted to determine the influence of initial salt concentration on the desalination process. The possibility of removing fluoride and nitrate from a groundwater containing about 4.3 g/L NaCl, as well as 2.8 and 31.3 mg/L of fluoride and nitrate respectively, as a function of applied voltage was also investigated. A laboratory electrodialysis stack containing seven cation-exchange membranes and six anion-exchange membranes of 56 cm2 effective area was used. From these studies it is demonstrated that electrodialysis is an effective method for the removal of fluoride and nitrate from brackish groundwater and that real groundwater showed a slower desalination behaviour. Fouling of the membranes was observed.
-
Bisphenol A retention in the direct ultrafiltration of greywater
01 November 2010University of EdinburghSchäfer, Andrea;Nghiem, Long D.;Oschmann, NadineDecentralised treatment is an increasing trend in the attempts to manage water more wisely in light of water restrictions, overconsumption and drought. Greywater is a fraction of household wastewater that offers the potential to be treated locally and then reused for garden irrigation, car washing and toilet flushing. In this paper the performance of submerged and direct ultrafiltration (UF) of synthetic greywater was investigated with regards to organic trace contaminant, namely bisphenol A (BPA), and fouling. The synthetic greywater solution consisted of inorganic particulates (kaolin), organic fibres (cellulose), protein (casein), surfactant (sodium dodecyl sulphate, SDS), humic acid (HA), calcium, sodium chloride electrolyte and sodium bicarbonate buffer. Results indicate that UF can remove 30–45% of BPA. This removal is attributed to partitioning of the compound to the membrane material, suspended and dissolved solids as well as the fouling layer. Humic acid and calcium were the main contributors to fouling, which also affected BPA retention. Fouling increased with an increase in HA concentration, which calcium contributed most to fouling at a concentration of about 0.5 mM. At higher concentration of calcium aggregation appeared to reduce fouling significantly. The implications of this study are that trace contaminant–solute interactions play an important role for retention potential and this relationship offers room for optimization by selecting particulate additives with a high affinity for target compounds. This is of particular importance if such contaminants are a concern (which is dependent on the product water application) and in the absence of biological treatment which is in this case not desired. The separation of greywater into fractions of low and high strength is of advantage if this can eliminate the presence of humic substances.
-
A performance comparison of individual and combined treatment modules for water recycling
01 November 2010University of EdinburghKhan, Stuart;Wintgens, Thomas;Sherman, Paul;Zaricky, Jan;Schäfer, AndreaAn Advanced Water Recycling Demonstration Plant (AWRDP) was commissioned and constructed by the Queensland State Government in Australia. The AWRDP was used to study the effectiveness of a variety treatment processes in the upgrading of municipal wastewater for water recycling applications. The AWRDP consists of eight modules, each housing an individual specific treatment process. These processes are flocculation, filtration, dissolved air flotation, ozonation, biological activated carbon adsorption, microfiltration, reverse osmosis and ultraviolet disinfection. The individual performances of the treatment processes were determined, as well as their interdependence in series. A range of chemical water quality parameters were investigated. The study provides a broad process comparison on the basis of an important catalogue of these key parameters. This will be valuable in the selection and optimisation of treatment processes trains in full-scale water recycling applications.
-
Testing of a hybrid membrane system for groundwater desalination in an Australian national park
01 November 2010University of EdinburghSchäfer, Andrea;Richards, Bryce S.The results of a field trial desalinating brackish bore water in an Australian remote national park site are reported in this paper. Two membranes, operated with varying operation pressures, were tested with regards to flux, recovery, retention, power and specific energy consumption. The aim of such a performance evaluation is the determination of a safe operating window when the system is driven with solar energy and hence a variable power source. Submerged ultrafiltration was effective in reducing high feedwater turbidity of up to 370 NTU. For the system, designed for a production of about 1000 L/d for remote communities, the specific energy consumption (SEC) was below 5 W.h/L when operated at a pressure above 7 bar. Retention of multivalent ions was stable at > 98% while the retention of monovalent ions varied between 88 and 95% depending on system pressure with a maximum between 7 and 10 bar.
-
Membranes and renewable energy — a new era of sustainable development for developing countries
01 November 2010University of EdinburghSchäfer, Andrea;Broeckmann, Andreas;Richards, BryceThis article outlines the combination of a small scale hybrid ultrafiltration and nanofiltration/reverse osmosis system with solar energy. The system is targeted to remote communities with access to either contaminated surface or brackish water. The treatment accomplishes dual barrier disinfection, desalination, and removal of trace contaminants such as arsenic. Investigation of the system is carried out for a variable power source that leads to fluctuations in feed flow and recovery. Those variations may affect water quality and fouling and to ensure satisfactory performance in locations far from qualified maintenance personnel this information needs to be integrated into process design and operation procedures. The system exhibits a very low specific energy consumption and is able to desalinate brackish water to drinking water guidelines. Trace contaminant removal is under investigation and results are not presented in this paper.
-
Occurrence of pharmaceutically active and non-steroidal estrogenic compounds in three different wastewater recycling schemes in Australia
01 November 2010University of EdinburghAl-Rifai, Jawad H.;Gabelish, Candace L.;Schäfer, AndreaThe discovery that natural and synthetic chemicals, in the form of excreted hormones and pharmaceuticals, as well as a vast array of compounds with domestic and industrial applications, can enter the environment via wastewater treatment plants and cause a wide variety of environmental and health problems even at very low concentrations, suggests the need for improvement of water recycling. Three Australian wastewater recycling schemes, two of which employ reverse osmosis (RO) technology, the other applying ozonation and biological activated carbon filtration, have been studied for their ability to remove trace organic contaminants including 11 pharmaceutically active compounds and two non-steroidal estrogenic compounds. Contaminant concentrations were determined using a sensitive analytical method comprising solid phase extraction, derivatization and GC with MS using selected ion monitoring. In raw wastewater, concentrations of analgesics and non-steroidal anti-inflammatory medications were comparable to those found in wastewaters around the world. Remarkably, removal efficiencies for the three schemes were superior to literature values and RO was responsible for the greatest proportion of contaminant removal. The ability of RO membranes to concentrate many of the compounds was demonstrated and highlights the need for continued research into monitoring wastewater treatment, concentrate disposal, improved water recycling schemes and ultimately, safer water and a cleaner environment.
-
Renewable Energy Powered Membrane Technology. 1. Development and Characterization of a Photovoltaic Hybrid Membrane System
01 November 2010University of EdinburghSchäfer, Andrea;Broeckmann, Andreas;Richards, BryceIn isolated communities where potable water sources as well as energy grids are limited or nonexistent, treating brackish groundwater aquifers with small-scale desalination systems can be a viable alternative to existing water infrastructures. Given the unavailability of power in many such situations, renewable energy is an obvious solution to power such systems. However, renewable energy is an intermittent power supply and with regards to the performance of intermittently operated desalination systems, only very limited experience exists, both with regards to efficiency as well as water quality. In this paper, this lack of knowledge is addressed by evaluating a system operated with varying parameters (pressure and flow) with constant power as a step toward defining a safe operating window, and they provide a basis for interpreting future data obtained with a renewable energy source. Field trials were performed on a brackish (5300 mg/L TDS; 8290 μS/cm) bore in Central Australia with a photovoltaic-powered membrane filtration (PV-membrane) system. Four nanofiltration and reverse osmosis membranes (BW30, ESPA4, NF90, TFC−S) and a number of operation parameter combinations (transmembrane pressure, feed flow, TFC-S) and operating parameters transmembrane pressure and feed flow were investigated to find the best operating conditions for maximum drinking water production and minimum specific energy consumption (SEC). The ESPA4 membrane performed best for this brackish source, producing 250 L/h of excellent drinking water (257 mg/L TDS; 400 μS/cm) at an SEC of 1.2 kWh/m3. The issue of brine disposal or reuse is also discussed and the article compares the salinity of the produced brine with livestock water. Since the feedwater is disinfected physically using ultrafiltration (UF), the brine is free from bacteria and most viruses and hence can be seen more as a reusable product stream than a waste stream with a disposal problem.
-
Binding of Estrone to Microfiltration Hollow Fibre Membranes in Filtration of Solutions Containing Trace Estrone
08 November 2010University of EdinburghChang, Sheng;Waite, T. D.;Schäfer, Andrea;Fane, Anthony G.Increased concern is being paid to the health and environmental risk caused by trace natural and synthetic hormones discharged from sewage treatment plant (STPs). This study, which is part of a larger project on investigation of hybrid membrane processes for trace hormones removal, focuses on binding of hormones to microfiltration hollow fibre membranes in filtration of solutions containing trace hormones. The adsorption capacity of the membrane, kinetics of adsorption and desorption of to/from microfiltration hollow fibre membranes, and the factors affecting adsorption to the membranes have been studied using estrone as model solute. The experiments showed that the adsorption of estrone to the microfiltration membranes could result in high retention of estrone molecules. However, since the mechanism of retention is adsorption rather than sieving, the retention decreases with increase in the amount of estrone accumulated on the membrane and breakthrough occurs when the accumulated estrone on the membrane reaches an equilibrium concentration corresponding to the feed concentration. For long-term operation, although membranes could be saturated by hormone molecules the membrane processes could still have a function of buffer for instantaneous high hormones concentration because the saturation surface concentration increased with the increase in the feed concentration. In addition, the experiments also indicated that the adsorption capacity of the membranes for hormones could be affected by membrane types, pH, affinity of hormones to water, as well as the presence of other organics. These results are of relevance to the potential release of trace hormones from water treatment systems where microfiltration membranes are used as a process barrier.
-
Adsorptive interactions between membranes and trace contaminants
09 November 2010University of EdinburghNghiem, L. D.;Schäfer, Andrea;Waite, T. D.Widespread occurrences of endocrine-disrupting chemicals (EDCs) in waterways have attracted a great attention of the scientific community. While scientific evidence associated with human health is restricted due to the long-term effects, impacts of EDCs on trout at the common concentration encountered in sewage effluent have been confirmed by both in vitro and in vivo studies. The impacts of steroid estrogens such as estrone, estradiol (natural hormones) and ethinylestradiol (a synthetic hormone) are often more serious than other synthetic EDCs as they have far higher endocrine-disrupting potency, despite of their low concentration. This paper investigates retention and adsorptive behavior of the natural hormones estrone by two commercial reverse osmosis membranes TFC-S and X-20, using dead end stirred cell systems. While an adsorptive process that reaches a breakthrough governs the retention of estrone by the TFC-S membrane; a sieving mechanism is responsible for the high removal of estrone using the X-20 membrane.
-
Particle interactions and removal of trace contaminants from water and wastewaters
09 November 2010University of EdinburghSchäfer, Andrea;Mastrup, M.;Jensen, R. LundThe adsorption of trace contaminants on natural particles is of great interest as this adsorption enhances the possibility of removing these with low pressure filtration such as MF and UF. This study shows that natural hormones such as estrone and estradiol will adsorb to natural particles both organic and inorganic. Experiments have shown that the adsorption capacity of organics is a factor of 10 higher than for inorganics. Ultrafiltration of a solution containing NOM and estrone also indicated this adsorption as the retention of estrone showed strong relationship to the concentration of organic material in the permeate. For practical application of this finding it was investigated if it applied to activated sludge. It was found that activated sludge does adsorb the natural hormones and that activated sludge during ultrafiltration develops a dynamic membrane which enhances the retention of the hormones.
-
Adsorption of trace steroid estrogens to hydrophobic hollow fibre membranes
10 November 2010University of EdinburghChang, Sheng;Waite, T. D.;Schäfer, Andrea;Fane, Anthony G.This paper discusses adsorption of estrone to microfiltration hollow fibre membrane from aqueous phase using estrone as the model compounds. The partitioning of estrone between membrane and aqueous phase at equilibrium state, the concept of membrane retention towards estrone caused by adsorption, adsorption kinetics, and the application potential of membrane adsorption have been assessed through batch adsorption and dead-end filtration of solution containing trace estrone. The results show that adsorption could result in significant accumulation of estrone on membrane surface. The partition of estrone between membranes and aqueous phase can be characterized by the Freundlich equation. The microfiltration membrane could exhibit high retention to estrone due to adsorption but the retention decrease with the increase in estrone amount accumulated on the membrane surface. Implication of this study is of an important nature, especially in drinking water applications. Contaminants such as natural and synthetic hormones may accumulate on the membranes and desorb during backwash or membrane cleaning. Further studies are needed to address risk issues involved.
-
Adsorption of Estrone on nanofiltration and reverse osmosis membranes in water and wastewater treatment
10 November 2010University of EdinburghNghiem, D.L.;Schäfer, Andrea;Waite, T.D.Adsorption of the trace contaminant estrone, a natural hormone and commonly abundant in surface waters and in treated as well as untreated wastewaters, to eight commercial nanofiltration (NF) and reverse osmosis (RO) membranes was investigated under welldefined conditions. Experiments were conducted in stainless steel stirred cells by spiking trace levels (100ng.L-1) of estrone into five different matrices, namely MilliQ water, a bicarbonate solution, synthetic natural waters containing natural organics, and secondary effluent. Results show that estrone is adsorbed to the membranes to varying degrees with extent of adsorption influenced by the feedwater composition with different mechanisms of association controlling adsorption to different membrane types. Increase in membrane resistance is typically observed to result in decrease in extent of estrone adsorption.
-
The role of endocrine disrupters in water recycling: risk or mania?
10 November 2010University of EdinburghNghiem, L.D.;McCutcheon, J.;Schäfer, Andrea;Elimelech, M.The widespread occurrence of endocrine disrupting chemicals (EDCs), such as steroid hormones, in secondary wastewater effluents has become a major concern in the water recycling practice. This paper investigates the risk of steroid hormone breakthrough during nanofiltration membrane filtration in water recycling applications. The results indicate a dynamic equilibrium between adsorption and desorption of steroid hormone with regard to the membrane. This equilibrium can be pH dependent and there is a possibility for release of steroid hormones at high pH during membrane cleaning procedures or erratic pH variations. Increase in water recovery can severely increase the hormone breakthrough concentration. The results also indicate a possibility of accumulation of steroid hormones in the NF membrane, followed by subsequent release.
-
Removal of hormones and pharmaceuticals in the Advanced Water Recycling Demonstration Plant in Queensland, Australia
10 November 2010University of EdinburghKhan, S.J.;Wintgens, T.;Sherman, P.;Zaricky, J.;Schäfer, AndreaAn advanced water recycling demonstration plant was employed to investigate the effectiveness of a number of treatment technologies in the removal of some residuals of commonly prescribed pharmaceuticals as well as natural and synthetic hormones found in sewage. Analysis of targeted compounds was carried out by solid-phase extraction (SPE) and gas chromatography-mass spectrometry (GC-MS). Initial tests were undertaken to determine the background concentrations of the analytes during various stages of treatment. Subsequent tests, undertaken by spiking with standard solutions of the target compounds provided further information on the removal efficiencies of some selected treatment modules. The results of the study indicate that while ozonation, microfiltration and nanofiltration were partially effective; treatment by reverse osmosis was the most universally successful in the removal of the target residuals. While significantly more data is required for a full evaluation, this initial investigation suggests that reverse osmosis may be an effective means of removing a wider range of pharmaceutically active residuals and hormones from treated sewage.
-
Chemical drinking water quality in Ghana: Water costs and scope for advanced treatment
15 November 2010University of EdinburghRossiter, Helfrid M.A.;Owusu, Peter A;Awuah, Esi;MacDonald, Alan M;Schäfer, AndreaTo reduce child mortality and improve health in Ghana boreholes and wells are being installed across the country by the private sector, NGOs and the Ghanaian government. Water quality is not generally monitored once a water source has been improved. Water supplies were sampled across Ghana from mostly boreholes, wells and rivers as well as some piped water from the different regions and analysed for the chemical quality. Chemical water quality was found to exceed the WHO guidelines in 38% of samples, while pH varied from 3.7 to 8.9. Excess levels of nitrate (NO3 -) were found in 21% of the samples, manganese (Mn) and fluoride (F-) in 11% and 6.7%, respectively. Heavy metals such as lead (Pb), arsenic (As) and uranium (U) were localised to mining areas. Elements without health based guideline values such as aluminium (Al, 95%) and chloride (Cl, 5.7%) were found above the provisional guideline value. Economic information was gathered to identify water costs and ability to pay. Capital costs of wells and boreholes are about £1200 and £3800 respectively. The majority of installation costs are generally paid by government or NGO, while the maintenance is expected to be covered by the community. At least 58% of the communities had a water payment system in place, either an annual fee/one-off fee or “pay-as-you-fetch”. The annual fee was between £0.3-21, while the boreholes had a water collection fee of £0.07-0.7/m3, many wells were free. Interestingly, the most expensive water (£2.9-3.5/m3) was brought by truck. Many groundwater sources were not used due to poor chemical water quality. Considering the cost of unsuccessful borehole development, the potential for integrating suitable water treatment into the capital and maintenance costs of water sources is discussed. Additionally, many sources were not in use due to lack of water capacity, equipment malfunction or lack of economic resources to repair and maintain equipment. Those issues need to be addressed in combination with water quality, coordinated water supply provision and possible treatment to ensure sustainability of improved water resources.
-
Application of solar-powered desalination in a remote town in South Australia
15 November 2010University of EdinburghDe Munari, Annalisa;Capão, D.P.S;Richards, B.S.;Schäfer, AndreaCoober Pedy is a remote town in South Australia with abundant solar radiation and scarce and low quality water, where a reverse osmosis plant has been operating since 1967. This paper evaluates the feasibility of powering the plant with solar or photovoltaic (PV) panels whilst avoiding energy storage in batteries. Pilot tests were performed in October 2005 with a small scale PV-powered hybrid ultrafiltration-reverse osmosis (UF/RO) membrane filtration system. The performance of the system in Coober Pedy is presented over different operating conditions and two available brackish feed waters. The system has been shown to tolerate well the power variation during clear sky days due to direct use of PV panels, producing 764 L of water per solar day with average specific energy consumption of 3.2 kWh.m-3 when treating the groundwater with conductivity of 7.4 mS.cm-1. It has been concluded that a reverse osmosis plant utilising UF pre-treatment and powered by PV panels without battery storage is a promising alternative for Coober Pedy to overcome currently high energy costs for the existing RO plant.
-
Physico-chemical water quality in Ghana: Prospects for water supply technology implementation
15 November 2010University of EdinburghSchäfer, Andrea;Rossiter, H.M.A.;Owusu, P.A.;Richards, B.S.;Awuah, E.During an extensive sampling trial in Ghana, a number of physico-chemical water quality problems have been identified. For example, pH values of the collected samples ranged from 3.69 to 8.88, while conductivity ranged from 10 to 45,000 mS/cm and turbidity from 0 to >542 NTU. Many water samples analysed breached the drinking water quality guidelines. High levels of heavy metals were found and also locations high in sulphate and nitrate. In some regions chemical contaminants such as fluoride occur naturally and result in a significant number of boreholes being capped. While such capping results in the protection of the population of exposure to such chemicals, it may increase the risk for microbiological safety if surface water sources are used.
-
Impact of speciation on fluoride, arsenic and magnesium retention by nanofiltration/reverse osmosis in remote Australian communities
15 November 2010University of EdinburghRichards, L. A.;Richards, B. S.;Rossiter, H.M.A.;Schäfer, AndreaIn order to provide safe drinking water in isolated communities where water supply and electrical infrastructure is limited, a system combining solar energy and advanced water treatment technology (a two-staged membrane process with ultrafiltration followed by nanofiltration/reverse osmosis) has been developed. The objective of this study is to model the speciation of commonly occurring and sometimes health-threatening trace contaminants, and then to evaluate the impact of speciation on fluoride, arsenic, and magnesium retention by nanofiltration/reverse osmosis. A series of experiments were performed in central Australia in late 2005 to assess elemental retention with four different membrane modules (BW30, ESPA4, NF90, and TFC-S) at various pH values between 3 and 11 at two different source waters (Pine Hill Station and Ti Tree Farm). The removal of fluoride and arsenic was observed to be independent of pH, while magnesium removal is pH dependent. Compound speciation is considered to explain dependence observations. Membrane type was found to impact retention. The results obtained in this study will provide valuable information on the reliability and the optimization windows of the renewable energy powered desalination system that has been developed
-
Removal of inorganic trace contaminants by electrodialysis in a remote Australian community
15 November 2010University of EdinburghBanasiak, Laura J.;Schäfer, AndreaWater provision for developing countries is a critical issue as a vast number of lives are lost annually due to lack of access to safe drinking water. The presence and fate of inorganic trace contaminants is of particular concern. Trace inorganic contaminants have been found in elevated concentrations in drinking waters supplied directly from brackish groundwaters in developing countries. Desalination and the removal of trace inorganic contaminants from bore water sources from a remote community in Australia using electrodialysis (ED) were investigated. The influence of applied voltage on the removal of the trace contaminants was evaluated. While the results from this study demonstrated that ED is an effectual method for the removal of total dissolved solids and a number of trace inorganic contaminants from brackish groundwaters to below drinking water guideline levels, the deposition of trace contaminants on the membranes (fouling) influenced the ED process in relation to ionic flux and the effectiveness of trace contaminant removal.
-
Adsorption of the Endocrine-Active Compound Estrone on Microfiltration Hollow Fiber Membranes
16 November 2010University of EdinburghChang, Sheng;Waite, T. David;Schäfer, Andrea;Fane, Anthony G.Results of studies reported here show that adsorption could result in considerable accumulation of hormones on hydrophobic hollow fibre membrane surfaces during filtration of trace-hormone containing feed solutions with a linear adsorption isotherm applicable over the majority of the estrone concentration range examined (2.6 to 154 ng/L). Models based on both diffusion and surface reaction limitation were used to describe the kinetics of estrone adsorption to the membranes tested. Results indicate that the rate of adsorption of estrone to the hollow fibre membranes was limited principally by surface reaction rate rather than the rate of diffusive transport to membrane surface sites. Both adsorption and desorption kinetics were satisfactorily described by pseudo-first order expressions. These results are of environmental significance, especially in drinking water applications, where contaminants such as natural and synthetic hormones may accumulate on the membranes and desorb during backwashing and membrane cleaning.
-
Predicting Fate of the Contraceptive Pill in Wastewater Treatment and Discharge
16 November 2010University of EdinburghMastrup, M.;Schäfer, Andrea;Khan, S.J.The risk of endocrine disrupters to humans and wildlife is to date poorly understood, although evidence of effects is now widespread. In understanding the risk, an important step is the determination of the partitioning, as well as chemical and biochemical transformation, of compounds in the environment, the water cycle and the food chain. This is a complex task and this paper is a first step towards estimating some of these factors from a largely theoretical approach. A chemical fate model is used to predict the fate of the contraceptive drug 17a-ethinylestradiol (EE2). The example of the contraceptive pill is chosen to follow the journey of the drug from human ingestion and excretion to treatment in a sewage treatment plant (STP) using fugacity-based fate models, followed by discharge into a receiving river and eventually into the estuary/sea. The model predicts how EE2 will partition into the different compartments during each stage of this journey and thereby infiltrate into the food chain. The results suggest that a person would have to ingest more than 30,000 portions of fish to consume an equivalent to a single average dose of the contraceptive pill. While this scenario is highly unlikely, the biochemical consequence of the contraceptive pill is greatly significant. Furthermore, there are many identified similarly estrogenic compounds in the environment while this study only considers one. Cumulative effects of such compounds as well as degradation into other potent compounds may be anticipated. An important message in this paper is the interrelation of wastewater effluent discharge and eventual human exposure of marginally degradable and lipophilic chemicals. While at present the main concerns regarding endocrine disrupters appear to be the fear of their occurrence in drinking water sources, it is clear that the domains of wastewater treatment and discharge, water supply and contamination of food should not be treated as separate issues. The model suggests that exposure from food (contaminated by effluent) may be much more significant than from drinking water.
-
Impediments to municipal water recycling in Australia
16 November 2010University of EdinburghKhan, S;Schäfer, Andrea;Sherman, PLocal authorities in Australia face two great challenges when managing municipal waters: Meeting future demands for clean water; and Preserving and enhancing the health of waterways. Municipal water recycling provides a means to achieve these objectives by providing an alternative source of water as well as reducing sewage effluent discharges. This paper identifies the key factors impeding the rate of growth of water recycling in Australia. Such knowledge will be crucial to our effective allocation of efforts and resources required for a rapid and sustainable change in the way we manage our water. While Australia currently recycles around 11 per cent of effluents from sewage treatment plants, there is substantial scope for increase.
-
Estrogenic hormone removal from wastewater using NF/RO membranes
16 November 2010University of EdinburghNghiem, L.D.;Manis, A.;Soldenhoff, K.;Schäfer, AndreaThis paper investigates the separation process of two estrogenic hormones, estrone and estradiol, using eight commercial NF and low pressure RO membranes. The results indicate that the separation mechanism of estrone and estradiol in membrane filtration processes is similar. While estrogenic hormone retention by porous membranes decreases with decreasing adsorption and the subsequent retention is relatively low, tight NF and RO membranes can retain estrogenic hormones effectively. It appears that the presence of organic matter in solution can enhance retention due to the interaction of such substances with estrogenic hormones. The results also suggest that physicochemical interactions within the membrane can play an important role. There is no cross flow effect on retention, whereas an increase in transmembrane pressure may lead to a decrease in steroid hormones retention for some membranes.
-
Renewable energy powered membrane technology. 2. The effect of energy fluctuations on performance of a photovoltaic hybrid membrane system
16 November 2010University of EdinburghRichards, B.S.;Capão, D.P.S.;Schäfer, AndreaThis paper reports on the performance fluctuations during the operation of a batteryless hybrid ultrafiltration – nanofiltration / reverse osmosis (UF-NF/RO) membrane desalination system powered by photovoltaics treating brackish groundwater in outback Australia. The renewable energy powered membrane (RE-membrane) system is designed to supply clean drinking water to a remote community of about 50 inhabitants. The performance of the RE-membrane system over four different solar days is summarised using four different NF membranes (BW30, NF90, ESPA4, TFC-S), and examined in more detail for the BW30 membrane. On an Australian spring day, the system produced 1.1 m3 of permeate with an average conductivity of 0.28 mS.cm-1, recovering 28% of the brackish (8.29 mS.cm-1 conductivity) feedwater with an average specific energy consumption of 2.3 kWh.m-3. The RE-membrane system tolerated large fluctuations in solar irradiance (500 – 1200 W.m-2), resulting in only small increases in the permeate conductivity. When equipped with the NF90 (cloudy day) and ESPA4 (rainy day) membranes, the system was able to produce 1.36 m-3 and 0.85 m-3 of good quality permeate, respectively. The TFC-S membrane was not able to produce adequate water quality from the bore water tested. It is concluded that batteryless operation is a simple and robust way to operate such systems under conditions ranging from clear skies to medium cloud cover.
-
Membrane filtration in water recycling: removal of natural hormones
16 November 2010University of EdinburghNghiem, L.D.;Schäfer, Andrea;Waite, T.D.Recent detections of endocrine-disrupting chemicals (EDCs) in effluent are of great concern by sections of the community associated with the issue of reclaimed water recycling. In vitro and in vivo studies by many researchers have confirmed the impacts of EDCs on trout at the common concentration encountered in sewage effluent. Amongst many types of EDCs the impacts of steroid estrogens such as estrone, estradiol (natural hormones) and ethinylestradiol (a synthetic hormone) are prominent as they have far higher endocrine-disrupting potency than other synthetic EDCs (Johnson and Stumpter, 2001). Performance of conventional wastewater treatment of different plants on removal of these compounds varies greatly and, concentrations of some steroid estrogens in secondary effluent are still able enough to harm wildlife such as fish in particular (Johnson and Stumpter, 2001). In spite of the magnitude of this problem, research on the removal of EDCs in water and wastewater treatment remains to date very limited due to their relatively low concentration and the associated analytical difficulties.
-
Assessment of Trace Estrogenic Contaminants Removal by Coagulant Addition, Powdered Activated Carbon Adsorption and Powdered Activated Carbon/Microfiltration Processes
16 November 2010University of EdinburghChang, Sheng;Waite, T. David;Ong, Peter E. A.;Schäfer, Andrea;Fane, Anthony G.Increasing attention is being paid to health and environmental risk as a result of the presence of trace steroid estrogens in the effluent discharged from municipal sewage treatment plants. This paper focuses on assessment of removal of these trace compounds using 3H-labelled estrone as the model compound. Jar tests over a range of ferric chloride dosage and pH conditions showed that coagulation was ineffective in removal of estrone from secondary effluent. The experiments showed that the combination of PAC and microfiltration could be effective for removal of trace estrone from water. The rate and extent of estrone removal by PAC are functions of PAC dosage and retention time of PAC in the system. Mathematical analysis of the results using a homogeneous surface diffusion model (HSMD) indicates that the adsorption of estrone on PAC can be limited by film diffusion and internal surface diffusion. The surface and film mass transfer coefficients were determined to be 9.72 x 10-10 cm2/min and 1.963 cm/min, respectively, under the conditions used.
-
The role of membrane processes in municipal wastewater reclamation and reuse
16 November 2010University of EdinburghWintgens, T.;Melin, T.;Schäfer, Andrea;Khan, S.;Muston, M.;Bixio, D.;Thoeye, C.Wastewater reuse presents a promising solution to the growing pressure on water resources. However, wastewater reuse implementation faces obstacles that include insufficient public acceptance, technical, economic and hygienic risks and further uncertainties caused by a lack of awareness, accepted standards, uniform guidelines and legislation. So far, there are no supranational regulations on water reuse in Europe and further development is slowed by lack of widely accepted standards e.g. in terms of required water quality, treatment technology and distribution system design and operation. Treatment technology encompasses a vast number of options and membrane processes are regarded as key elements of advanced wastewater reclamation and reuse schemes and are included in a number of prominent schemes world-wide, e.g. for artificial groundwater recharge, indirect potable reuse as well as for industrial process water production. For dual reticulation purposes in urban areas two types of systems have been built, a centralised type of treatment with dual membrane processes, including e.g. microfiltration (MF) and reverse osmosis (RO), and small scale systems using membrane bioreactors. This paper will provide an overview of the status of membranes processes in wastewater reclamation and reuse world-wide and will depict their potential role in promoting more sustainable water use patterns.
-
Fouling mechanisms of submerged ultrafiltration membranes in greywater recycling
16 November 2010University of EdinburghOschmann, Nadine;Nghiem, L. D.;Schäfer, AndreaThis study examined the influence of greywater constituents on the fouling behaviour of submerged hollow fibre UF membranes during greywater treatment for recycling purposes. Experiments were carried out on a bench-scale equipment using a Zenon ZW1 module. The membrane was operated under constant flux where an increase in transmembrane pressure was used to determine the extent of fouling. Wastewater constituent variables used in this study were kaolin, cellulose, humic acid, surfactant, and calcium concentration. Results indicate that during filtration of synthetic greywater multivalent ions like calcium played an important role. Depending on concentration agglomerates of different structure and size were formed and the structure and size determined the extent of fouling and retention. It was also shown that the surfactant sodium dodecyl sulphate (SDS) may cause fouling through particle stabilisation and strongly interacts with calcium enhancing calcium retention especially in the critical micelle concentration (cmc) region. It is hypothesized that SDS competes with humic acids (HAs) for adsorption sites resulting in lower UV254nm retention. Solution chemistry and cake deposition also influence the retention and hence product water quality.
-
Performance of a small solar-powered hybrid membrane system for remote communities under varying feedwater salinities
16 November 2010University of EdinburghSchäfer, Andrea;Remy, C.;Richards, B.S.An estimated 1 billion people are living both without access to clean drinking water or electricity. The small photovoltaic (PV)-powered hybrid membrane system described here is designed to address the plight of some of these people. PV and membrane technologies are chosen due to suitability for operation in remote and often harsh conditions. An ultrafiltration (UF) pre-treatment is included to remove bacteria and most pathogens, while a reverse osmosis (RO) or nanofiltration (NF) membrane desalinates the brackish feedwater. Several parameters were examined in order to optimise the system performance, including i) feed salt concentration, ii) operating pressure, iii) system recovery, iv) specific energy consumption (SEC, kWh/m3), and v) salt retention. In addition, experiments were performed over a whole day to determine system performance under varying levels of solar radiation. The minimum SEC (relatively high due to the current single-pass mode of operation) varies from 5.5 kWh/m3 at a feed concentration of 1 g/L salt to 26 kWh/m3 at a feed concentration of 7.5 g/L salt, which is the upper limit of the system in terms of salt concentration.
-
Removal and fouling mechanisms in nanofiltration of polysaccharide solutions
16 November 2010University of EdinburghBroeckmann, A.;Wintgens, T.;Schäfer, AndreaTubular membrane filtration is an important process when feed waters with a relatively high solids content are filtered. Such solids would normally have to be removed in a pre-treatment stage if spiral wound modules are to be used. High solids content occurs for example in high turbidity surface waters, wastewaters that contain fibrous materials or in waters where coagulants are added. Tubular membranes can be used directly in nanofiltration (NF) and in this study fouling by a solution containing polysaccharides is examined. The study was designed in view of a wastewater recycling application where polysaccharides like cellulose are a major constituent of the effluent organic matter (EfOM) and colloidal organics. The investigation was performed with various organic compounds and varying solution chemistry namely pH and ionic strength. Two solutes in several concentrations have been used: Cellulose (particulate) and microcrystalline cellulose (colloidal) in addition with various CaCl2 and NaCl concentrations. The operating parameters investigated were cross flow velocity, transmembrane pressure (TMP) and pH. Membranes were cleaned after each filtration experiment and flux recovery was measured. As a general trend, it was observed that with increasing cellulose concentration fouling increases and that solution chemistry plays an important role in the association of foulants with the membranes. The permeability decreases for high and neutral pH conditions in the presence of salt ions. Calcium affects the flux more than sodium. The permeability at acidic pH values is relatively low and not influenced by the ions as much as for other pH conditions. Electrostatic interactions between membrane, salt ions and cellulose can explain this behaviour. Calcium ions were confirmed to play an important role in membrane fouling. Increasing cross flow velocity decreases the reversible fouling but increases the irreversible fouling.
-
System design and performance testing of a hybrid membrane — photovltaic desalination system
16 November 2010University of EdinburghMasson, Laurent;Richards, B. S.;Schäfer, AndreaIn some areas limited water resources combined with the fast growing population are leading to a crucial situation because of the increase in water demand. Besides, an estimated one billion people are living both without access to clean drinking water or electricity. Therefore, a stand alone photovoltaic-power based hybrid membrane desalination prototype has been designed to meet this challenge. Several parameters were examined in order to optimise the system performance, including i) feed water salt concentration, ii) operating pressure, iii) system recovery, iv) specific energy consumption (SEC) and v) salt retention. With a SEC varying from 2.2 to 7.7 kWh.m-3, the installation designed for remote villages is able to produce up to 1.2 m3.d-1.
-
Setting the standard for research excellence
04 August 2016University of EdinburghTate, Dominic;Green, RobFeature article in CILIP Update about the Jisc pathfinder project LOCH (Lessons in Open Access Compliance)
-
Focus on 14 sewage treatment plants in the Mpumalanga Province, South Africa in order to gauge the efficiency of wastewater treatment
09 February 2016University of the WitwatersrandSamie, A;Obi, C L;Ingumbor, J A;et alIn order to identify the treatment methods used in different sewage treatment plants (STPs) in the Mpumalanga Province and to determine the efficiency of wastewater treatment by these plants, municipal STPs were surveyed, and raw and treated wastewater samples collected. A total of 14 STPs were visited and the collected samples were analysed for physicochemical and microbiological parameters using standard methods. The treatment methods identified included ponds, activated sludge and trickling filters. The reduction of turbidity by the plants varied between 6.2 and 99.6% while conductivity, pH and temperature varied slightly between the influent and the effluent wastewater. Thirteen (92.8%) of the plants used chlorine for disinfection of the final effluent, however only 2 (14.2%) of the plants managed to produce effluent with 0 (zero) faecal conforms per 100 m€. Common pathogenic bacteria isolated from the final effluent included Salmonella, Shigella, Escherichia coli, Vibrio spp. and Enterococcus spp. The final effluent was used for irrigation and recycling purposes in 4 plants, all the other treatment plants discharged the effluent into the river or to the environment. The present study indicated that there is a move toward the renovation of wastewater treatment by the municipalities in the Mpumalanga Province with the adoption of biological treatment. All the STPs reduced the turbidity of wastewater as well as the different microbial indicators counts; however, several pathogenic bacterial organisms could still be detected in the final effluent. Further studies are needed to confirm the role of the treatment procedures on nutrient reduction and elimination of other viral and parasitic pathogens by the sewage treatment plants.
-
Comparison of three fluorosis indices in a Namibian community with twice optimum fluoride in the drinking water
29 April 2016University of the WitwatersrandCleaton-Jones, P.;Hargreaves, J. A.In Otjiwarongo, a town in Namibia with twice the optimum fluoride in the drinking water (1.56 ppm) the Dean (Dean, Arnold and Elvove, 1942), Thylstrup and Fejerskov (Thylstrup and Fejerskov, 1978) and TSIF (Horowitz et al, 1984) indices of fluorosis were compared in permanent teeth of the children aged 11 y living in the region. Fluorosis severety was skewed in all instances to lower scores within each index. With the Thylstrup and Fejerskov and TSIF indices it was possible to compare fluorosis by individual teeth; the former was significantly more sensitive in diagnosis (56 per cent vs 50 per cent prevalence). It is recommended that the aims of a fluorosis investigation be carefully detailed before selecting the fluorosis index to be used. If detailed information on individual teeth related to fluoride ingestion is needed the Thylstrup and Fejerskov index is recommended, especially in areas with raised fluoride intakes where it is anticipated that the fluorosis levels will be mainly in the low levels of severity
-
Permanent denition caries in KwaZulu and Namibia 11-year-olds
29 April 2016University of the WitwatersrandHargreaves, J. A.;Cleaton-Jones, P.;Matejka, J.;et alThe permanent dentitions of 11-year-old children in Namibia (n = 295) and KwaZulu (n = 308) living in rural and urban areas were examined using WHO caries diagnostic criteria. In low fluoride areas (less than 0.15 ppmF) significantly more caries was present in rural compared to urban KwaZulu but the prevalences in rural and urban Namibia were similar although significantly higher than in an area with 1.56ppmF in the drinking water. There was significantly more caries in rural Namibia than KwaZulu but the urban prevalences in both regions were similar. It is suggested that the urban findings are useful predictors for the needs of 11-year-old black children but local baseline surveys should be undertaken before considering dental programmes, treatment or preventive, for different rural communities in South Africa.
-
Water use efficiency of Manihot Esculenta Crantz under drip irrigation system in South Western Nigeria.
04 November 2016University of the WitwatersrandOlanrewaju, O.O.;Olufayo, A.A.;Oguntunde, P.G.;Ilemobade, A.A.Field experiments was conducted at Teaching and Research Farm, Federal University of Technology, Akure between November 2006 and November 2007 to find out the water use efficiency under drip irrigation system and effect on the growth and yield of Cassava (Manihot esculenta Crantz). A popular hybrid of cassava TMS 30572 was tried as a test crop. The soil of the experimental site was moderately drained, loamy sand. The experiments were laid out in a 4 × 4 × 2 randomised complete block design (RCBD) consisting of 4 treatments, 4 replicates and 2 varieties using a spacing of (1m × 0.8m) for mechanical harvesting. The results indicated that the highest moisture content was recorded at depth of 40cm during the late stage of tuber development and the highest biomass yield was recorded under full irrigation treatment than in other treatments. The yield of cassava ranged from 21.87 to 14.13 t ha-1 in all the treatments except for the control that has 8.45 t ha-1 while the water use efficiency ranged from 19.18 to 23.63 kg ha-1mm. Irrigation through full treatment registered the highest mean tuber yield of 21.87 t ha-1 while the least tuber yield was associated with the control treatment. The height and stem diameter of cassava also responded higher under full treatment of available water. This study demonstrated that medium irrigation (60% AW) could be best option in terms of water efficiency.
-
Treated wastewater reuse in South Africa: Overview, potential and challenges.
04 November 2016University of the WitwatersrandAdewumi, J.R.;Ilemobade, A.A.;Van Zyl, J.E.Many communities in South Africa struggle to access reliable and adequate quantities of potable water for diverse water requirements. This is against the backdrop of decreasing freshwater availability and increasing water demands. Currently, interest in the reuse of wastewater for non-drinking water requirements is increasing. This paper therefore provides an overview of the South African water resources situation and wastewater 1 generation in order to put the need for wastewater reuse into perspective. Potential for broader implementation and parameters influencing wastewater reuse based on local attitudes and experience were discussed with recommendations to facilitate broader implementation of wastewater reuse. This paper concludes that significant potential exists for implementing wastewater reuse for large non-drinking applications (e.g. landscape irrigation and industrial processes) in arid areas of South Africa especially Western Cape Province. Parameters highlighted from local attitudes and experience to influence broader implementation in addition to aridity include distance from source, retrofitting versus new installations, quantity of reuse, tariffs, source quality, public health, willingness, public trust and knowledge, and regulations and guidelines for reuse. Prior to implementation, it is recommended that these parameters be addressed.
-
Using genetics to prioritise headwater stream fish populations of the Marico barb, Enteromius motebensis Steindachner 1894, for conservation action.
11 October 2017University of the Witwatersrandvan der Walt, K.-A.;Swartz, E.R.;Woodford, D.J.;Weyl, O.South Africa has a relatively large number of threatened freshwater fish species and limited resources to implement conservation programs. Enteromius motebensis was regionally prioritised for action because of its conservation status and flagship status in a nationally important aquatic ecosystem. Genetic diversity of E. motebensis in headwater refugia of the Groot Marico River Catchment was assessed to determine if genetic diversity is important for conservation planning for this species. The results of the genetic analysis indicate that some prioritisation was possible, with two populations showing evidence of recent isolation. Conservation implications: We recommend that at least three populations be prioritised for conservation action to ensure maintenance of most of the remaining genetic diversity of the species.
-
Generalized storage-yield-reliability relationships for analysing shopping centre rainwater harvesting systems.
27 November 2017University of the WitwatersrandNdiritu, John;Moodley, Yashiren;Guliwe, MondliThe objective of this study was to develop guidelines for analysing rainwater harvesting (RWH) systems of shopping centres in South Africa. A model consisting of three dimensionless relationships relating rainwater supply and demand to storage capacity, yield and reliability was formulated. Data from daily simulation of potential RWHsystems of 19 shopping were used to obtain the relationships. The simulations revealed within-year storage behaviour with considerable variation of annual yield. By applying the Weibull plotting position formula, yield-reliability relationships were derived. The aim to maximize yield and reliability whilst minimizing storage identified Pareto-optimal combinations of the three variables and these combinations were used to develop two dimensionless relationships. An additional relationship based on the dependence of the slope of the yield-reliability plots on yield was formulated to enable analysis of hydrologically non-optimal systems. Verification tests using four RWH systems obtained results that matched those from simulation and the model could therefore be applied for RWH feasibility analysis and preliminary design. This study highlights the need to incorporate inter-annual variability in RWH analysis and shows how reliability can be used to quantify this. This study further demonstrates how reliability can be fully integrated into regression relationships for generalized RWH analysis.
-
Review of available data for a South African Inventory of Inland Aquatic Ecosystems SAIIAE
23 April 2019University of the WitwatersrandVan Deventer, Heidi;Petersen, Chantel;Mbona, Namhla;Smith-Adao, Lindie;Skowno, Andrew;Nel, Jeanne LThe National Biodiversity Assessment of 2011 found freshwater ecosystems to be highly threatened and poorly protected. However, a number of studies have shown that the National Wetland Map (NWM) Version 4 represents less than 54% of wetlands mapped at a fine scale. A more comprehensive South African Inventory of Inland Aquatic Ecosystems (SAIIAE) would greatly improve the assessment of wetland ecosystem types and their condition and conservation status, and is crucial for monitoring trends to inform decision making and planning. In preparation for the third National Biodiversity Assessment of 2018, a review was undertaken to identify possible data sources that could contribute to the SAIIAE. The objectives of the study were to (i) assess which type of information is available for developing a SAIIAE; and (ii) list and understand the availability of fine-scale wetland data for updating the NWM. A variety of data related to species occurrence and distribution, extent and type of inland wetlands and rivers, as well as datasets which describe regional settings of inland aquatic ecosystems, were found across a number of institutions. Fine-scale spatial data amounted to more than double the extent of inland wetlands mapped by remote sensing at a country-wide scale. Nearly 5 million ha of fine-scale data were collected from a diverse number of institutions, with the majority (73%) of these data mapped by Government (3 681 503 ha or 3% of South Africa). It is estimated that < 8% of the sub-quaternary catchments of South Africa had complete wetland data sets, primarily in the Gauteng, Mpumalanga and Western Cape Provinces. Accuracy assessment reports and confidence ratings were however not consistently available for the wetland datasets. Inland wetlands in the majority of South Africa (84%) therefore remain poorly represented. We recommend future steps to improve the SAIIAE, including improving the representation of inland wetland ecosystem types and focusing on accuracy assessment.
-
The right of access to adequate water [discussion of Mazibuko v The City of Johannesburg Case no 13865/06]
01 September 2009North West UniversityJansen van Rensburg, LindaThe Constitution of the Republic of South Africa, 1996 guarantees everyone the right to access to adequate water and places an obligation on the state to take reasonable measures, within its available resources, to achieve the progressive realisation of this right. This discussion focuses on the possible implications of the recent High Court case of Mazibuko v The City of Johannesburg case no 13865/06 for socio-economic jurisprudence in South Africa.
-
On the use of diatom-based biological monitoring Part 2: A comparison of the response of SASS 5 and diatom indices to water quality and habitat variation
02 September 2009North West UniversityVan Rensburg, Leon;De la Rey, Pieter Arno;Roux, H.;Vosloo, A.Due to the fact that South Africa is a water-scarce country, integrated water resource management based on sound information is essential. Bio-indicators have provided valuable information for water resource management in recent years and have enjoyed increasing popularity. Bio-indicators especially stepped to the forefront with the realisation that aquatic eco-systems are not only a source of water but also deliver several goods and services, as well as being essential for industrial growth and quality of life of many South Africans. This study aimed to quantitatively test two kinds of biomonitoring tools namely diatom-based (SPI and BDI) and macro-invertebrate based (SASS 5) in order to assess their applicability in South African River systems; and whether any additional information can be gained by using the two tools in tandem. The results showed that diatom indices are affected more by changes in water quality than SASS 5, while SASS 5 displayed a higher dependency on habitat quality, as measured by IHAS, than the diatom indices. It is therefore suggested that the two indices be utilised as complementary indicators for integrated assessment of river health.
-
A physical environmental management perspective on municipal water supply: proposals for Tlokwe City Council
17 December 2009North West UniversityNealer, Eric;Raga, KishoreAll South Africans, especially, those involved with the development and management of its water resources should be aware that South Africa is generally an arid to semi-arid region, with an average rainfall of approximately 500 mm per annum, compared to a world average of 860mm. Consequently, potable water is a very scarce resource, and is often the biggest prohibiting factor for development of, for example, new residential areas in a town or city. Hence a public service rendering municipality like the Tlokwe (Potchefstroom) City Council will have to, in its quest to manage its potable water supply more effectively, efficiently and economically, take cognisance of aspects such as: · The origin of its potable water; · The nature and extent of the storage and treatment of the potable water; · The manner in which the potable water is distributed to the users and consumers; and · The manner in which the wastewater is collected, treated and managed. The authors of this article are of the opinion that the aforementioned can only be taken care of effectively by incorporating a physical environmental management perspective in its municipal governance.
-
A short comparative history of wells and toilets in South Africa and Finland
07 January 2011North West UniversityHaarhoff, Johannes;Juuti, Petri;Mäki, HThis paper describes the technological development of wells and toilets and the cultural practices related to them in two countries, South Africa and Finland, from the Middle Ages to modern times. Wells and toilets have always been linked to the well-being of humans and they still are the most common technical systems in the service of mankind. They are simple to build, but if they are constructed improperly or stop functioning properly, they may endanger the health of both humans and the environment. The solutions used for getting clean water or for disposal of excrement have always been a matter of life and death for human settlements. Located on opposite sides of the world, the climate and natural resources of South Africa and Finland are very different. However, surprisingly similar solutions, for example wind turbines to pump water, have been used in rural areas. Furthermore, urbanization and industrialization occurred in both countries at approximately the same time in the 19th century, which caused increasing environmental problems in Finnish and South African urban areas. The transition to modern water supply and waste disposal systems was a very demanding process for municipal administrations in both countries.
-
Aspects of irrigation development in the Netherlands East Indies
07 January 2011North West UniversityErtsen, Maurits WThe ‘Romijn’ discharge measurement structure was developed in the Netherlands East Indies. By the end of the colonial period in the 1930s, it had become the standard structure in irrigation. The Romijn design is not only still the main discharge measurement structure in Indonesia, it is also used in Dutch water management practice and education. The question of continuity is at the heart of concepts such as ‘technological tradition’ or ‘technological regime’, and this continuity links the information embodied in a community of practitioners with the hardware and software the members master. Such communities define accepted modes of technical operation. Engineering education is an important mechanism in preference-guided selection of design solutions, and obtaining an engineering degree is much like passing the preparatory requirements for community membership. When, in 1967, a civil engineering student from Delft Polytechnic presented his final paper for an irrigation design to his supervisors, the first question they asked was why he had not used a Romijn weir as an off-take structure. The Dutch irrigation regime, which consists of the explicit and implicit rules of Dutch irrigation design, is the central subject of this paper. In this paper I shall discuss two related issues: (1) how the Netherlands East Indies irrigation regime developed, and (2) how the (dis)continuities in irrigation education and practice following Indonesian independence can be understood. Naturally, while discussion of these issues, to a certain extent at least, depends on the data available, it also depends on the researcher’s perspective.
-
Some human actions in the destruction and construction of culture and nature – the Merafong region as a case study
10 January 2011North West UniversityVan Eeden, Elize SFor at least the past 180 years the Merafong Municipal region in the Gauteng Province of South Africa, (of which the Wonderfontein Catchment forms a part) has strongly relied on the primary sector for its economic existence and development. In the process some human actions, also related to serious water contamination/pollution, have resulted in phases of constructions1 as well as economic and health destructions. Differences over whose environment and whose nature it is spontaneously developed, with sometimes less friendly outcomes. The ‘end result’ up to 2006 is a complicated scenario experience, similar to that of many other regions or local areas, but also very unique and somewhat frightening. The long term focus of this article is to exchange knowledge2 on the region with the objective to contribute towards creating a sustainable environment by ensuring closer co-operation between the various economic active cultures operating or functioning in the Merafong municipal region. In this article four aspects are covered.
-
The Vaal River Barrage, South Africa’s hardest working water way: an historical contemplation
11 January 2011North West UniversityTempelhoff, J.W.N.;Munnik, Victor;Viljoen, MornéSouth Africa’s Vaal River is the country’s hardest working rivers. It has been instrumental in securing valuable water supplies in the development of the country’s economic hub – the Gauteng Province. Since the mid-twentieth century there have been increasing indications of water pollution threatening the storage facility of the Vaal River Barrage, built by the water utility, Rand Water, at the start of the twentieth century. Currently, as a result of a variety of factors, untreated wastewater is posing a severe environmental threat in the Vaal River Barrage Catchment area. In the article attention is given to the origins of pollution and recent events that had the effect of mobilising grassroots anger in civil society with the state of affairs. The article forms part of a transdisciplinary research project that is currently conducted at North-West University’s Vaal Triangle campus in Vanderbijlpark.
-
Hidden benefits of public private partnerships: the case of water pressure management in Sebokeng
12 January 2011North West UniversityMckenzie, R S;Wegelin, W;Mohajaneand, P;Shabalala, SMany water distribution systems in South Africa are deteriorating due to many years of neglect resulting in a serious maintenance backlog. Recent government legislation has introduced free basic water to all South Africans up to a limit of 6 Kl/month per property which in turn causes certain confusion regarding payment among many residents. These key issues and others have led to serious problems with service delivery specifically in the low income areas where the maintenance has been neglected for more than 30 years in some cases. The potential for support from the Private Sector has been highlighted at the highest levels within government as a possible solution to addressing the existing backlogs despite the fact that there are relatively few successful projects to support this view. This paper presents the results after 30 months of operation of a small scale public private partnership in one of the largest low income areas in South Africa where the Sebokeng/Evaton Pressure Management Project was commissioned in July 2005. The savings both in terms of volume of water saved as well as financial savings to the municipality are impressive and exceed all initial expectations. The most interesting a1spect of the project, however, is not the savings achieved from the installation, but the numerous other additional benefits that have materialised which were not originally anticipated when the project was commissioned. Such benefits, include the identification of many network problems that had been undetected for more than 9 years as well the sudden interest in helping the residents by several government and semi-government organisations. These organisations were unable or unwilling to provide any support to the area prior to the successful Public Private Partnership. The project represents a significant advancement in Public-Private Partnerships (PPP’s) and clearly demonstrates that small scale Public Private Partnerships can be viable despite the general view that this type of project is confined to large scale initiatives due to the effort and expense in developing the PPP type of contract. The paper provides details of the processes involved in setting up and implementing such a project and highlights that the model used by the Project Team to address leakage in Sebokeng and Evaton can be adapted for use in other areas and other applications to improve service delivery throughout South Africa as well as elsewhere in the world where conditions permit. The paper presents the results from the project after the first 30 months of operation and summarises some of the many additional benefits that have arisen from the project.
-
Water users’ associations from the users’ perspective: local water management at Thabina irrigation scheme, Limpopo, South Africa
13 January 2011North West UniversityOrne-Gliemann, MaudAt a time when the South African water department and a circle of water experts in the country are defining their position on water users’ associations (WUAs), this paper looks at people’s actions and perceptions of local water management as a fundamental factor to understanding small farmers’ interactions with these newly established institutions. It presents the preliminary results of a community study conducted at Thabina irrigation scheme, Limpopo, between September 2007 and April 2008. This study offers an original approach to analyzing the scheme’s difficulties and, without providing a representative image of smallholder irrigation schemes in South Africa, it allows for interesting preliminary reflections around small farmers’ perceptions of water management and local water management institutions. The study of perceptions is not new, nor does it belong as an analytical tool to one or other academic discipline. In order to fully grasp this complex and multidimensional object, a transdisciplinary approach is therefore applied and implemented in the field by using an innovative set of methods: interviews, verbal associations and participatory photography. The advantages and difficulties related to the use of a perception and transdisciplinary approach are discussed.
-
Environmental ethics and crime in the water affairs of the Wonderfontein Spruit Catchment, Gauteng, South Africa
13 January 2011North West UniversityVan Eeden, Elize S;Liefferink, M;Tempelhoff, EThis article provides an analysis of the water history regarding the Wonderfontein Spruit Catchment in the former Far West Rand in South Africa. The major scope for discussion is a short analysis of environmental ethics and crime in this area in the past, and how it has affected man and environment as analysed from a 21st Century perspective. The Wonderfontein Spruit Catchment forms part of the present-day Merafong municipal area, formerly Carletonville. Although voices of concern have featured prominently since the 1960s and even earlier, no extraordinary ethical approach towards this environment and its inhabitants is recorded in history. Bibliographic sources of the Wonderfontein Spruit Catchment currently number over 5000 entries. Despite this impressive production resulting from especially research, reports and whistle blowing in the past 55 years, the area was exposed to limited and insufficient ethically inspired actions, that should have had the ingredients to confirm a positive approach by primary role players regarding environmental management.
-
Privatisation and water governance in Africa: implications of a rights-based approach
13 January 2011North West UniversityOlowu, 'DejoEarly in the post-independence era, the control of water resources in many African states was a task of central planning. Regrettably, water management soon became a miry adventure in most African states largely because of warped planning and implementation. This article examines the phenomenon of private sector involvement in water resources management and seeks to understand the effect of such involvement on the right to water in Africa in the context of the Millennium Development Goals. The article explores the continuing relationship between African governments and non-state actors in the management of water resources in the privatisation age. The article further analyses the role of various national water governance initiatives vis-à-vis the efficient management of water resources and the sharp contradictions in their frameworks from a rights-based perspective. It evaluates the normative frameworks of access to water as a human right in Africa and contends that the human being must be placed at the centre of water discourses in assessing all role actors and their responsibilities. Extrapolating from experiences from various states within and outside Africa, this article advocates a rights-based approach to water issues and its value for the ultimate purpose of humancentred development.
-
“Crossing over”: appropriate private sector principles, to operate more reliable public sector water services
13 January 2011North West UniversityWall, KPrivate sector institutions utilise many different business methods, some of which can selectively be adapted for use by organisations outside the private sector, to the benefit of their service delivery responsibilities. But the best of the appropriate practices from the private sector have often “not crossed over”. The Water Research Commission (WRC) of South Africa, working in collaboration with the Council for Scientific and Industrial Research (CSIR), finds that the concept of franchising, so successfully used by the private sector to deliver many goods and services, if applied to water services operation and maintenance, could alleviate and address many challenges in the management of water services. At the same time, franchising could provide an ideal stimulus to support the development of local enterprises, all within the municipal service delivery environment. Franchisee water service providers, dependent for their livelihood on the success of their business, would have a strong incentive to perform, and would also enjoy the benefit of the franchisor’s expert guidance and quality assurance. Some areas for potential franchising include meter management, billing, plumbing, pressure management, sewer maintenance, and wastewater treatment processes. The help from the franchisor would be of particular value to water services authorities at a distance from the major urban centres. Few of these authorities can afford to employ competent qualified staff, and often non-compliance with the laid down performance standards is a direct consequence of this lack. Significant improvements would soon be seen if the generally under-qualified and under-resourced water services staff could have this ongoing support, mentoring and quality control — or if the authority could enter into partnerships with small local enterprises or NGOs which would, through franchising, enjoy the necessary ongoing support, mentoring and quality control, and would have quick access to expert assistance when they needed it.
-
Neighbourhood effects and household responses to water supply problems in Nigerian cities
13 January 2011North West UniversityAcey, CharismaBetween 1990 and 2004, Nigeria’s urban population jumped to nearly half the national population, while access to improved sources of water in urban areas dropped by nearly 15 per cent during the same period. This paper presents preliminary results on the relationship between water supply, neighbourhood characteristics, and household strategies in response to dissatisfaction with water provision as reported by 389 respondents in 10 neighbourhoods in Lagos and Benin City, Nigeria between October 2007 and February 2008. In this paper, a conceptual model of consumer demand for water is used, based upon Hirschman’s exit, voice and loyalty (EVL) framework. The model explicitly factors in the quality of water provision and variables at the household and neighbourhood levels that could affect perceptions about quality and the strategies that households use to cope with inadequate public services. Preliminary results show that reported household strategies to secure water are affected by community-level factors such as the range, cost, and quality of water supply alternatives, as well as neighbourhood composition. Furthermore, the percentage of urban migrants and households that live in rented flats in a neighbourhood seems to be associated with the use of exit strategies (as opposed to voice) in response to problems with their primary water supply.
-
Disinfection by-products and extractable organic compounds in South African tap water
14 January 2011North West UniversityNothnagel, C.;Kotte, K.;Pienaar, J.J.;Van Zyl, P.G.;Beukes, J.P.An important step in urban purification of drinking water is disinfection by e.g. chlorination where potential pathogenic micro-organisms in the water supply are killed. The presence of organic material in natural water leads to the formation of organic byproducts during disinfection. Over 500 of these disinfection by-products (DBPs) have been identified and many more are estimated to form during the disinfection step. Several DBPs such as trihalomethanes (THMs), which is carcinogenic, poses serious health risks to the community. There is very few quantitative data available which realizes the actual levels of these compounds present in drinking water. The levels of four THMs present in drinking water were measured. It included chloroform, bromodichloromethane, chlorodibromomethane and bromoform. Although microbiological parameters are considered to get more attention than disinfection by-products, the measurement of the levels of these compounds in South-African drinking water is essential together with establishing minimum acceptable concentration levels. The target range for total trihalomethanes (TTHMs) established by the US EPA at the end of 2003 is 0-0.08ug/mL. The aim of this paper is to create an awareness of the problem as well as presenting preliminary results obtained with the method of analysis. Preliminary results indicate that urgent attention must be given to the regulation and monitoring of DBPs in South African drinking water.
-
Black workers, typhoid fever and the construction of the Berg River – Saldanha military water pipeline, 1942 – 1943
14 January 2011North West UniversityVisser, G E;Monama, F LWar creates a huge need for labour to support the war efforts of the belligerent parties. In South Africa tens of thousands of ‘non-white’ workers were mobilised during the Second World War to satisfy the Union Defence Force’s (UDF’s) labour needs at home and abroad. This article, firstly, outlines the role of ‘non-white people’, particularly black Africans, in the UDF with special reference to those employed within the Union of South Africa. Secondly, it briefly delineates typhoid fever as an historical thorn in the flesh of military forces up to the early 20th century. It then looks briefly into the incidence of and perceptions on typhoid fever as a killer disease in South Africa on the eve of the Second World War. Against that background, the article investigates the employment of black workers on the construction of the Berg River-Saldanha Bay military water pipeline and the UDF’s response to the threat and subsequent outbreak of typhoid fever amongst the workers at the Berg River intake site in 1943. The article concludes that the public health authorities and UDF were aware of the threat of typhoid fever with regard to the Berg River water scheme, but did not take sufficient precautionary measures, which could have had serious repercussions for the Allied war effort. This incident should serve as a warning to the South African National Defence Force when deploying on peace support operations on the African continent where typhoid fever remains a serious threat next to Hiv/Aids.
-
Controlling the farmer: colonial and postcolonial irrigation interventions in Africa
14 January 2011North West UniversityErtsen, Maurits WAiming at full control over farmer actions was a shared characteristic of colonial irrigation engineering approaches. However, the way control was sought in African irrigation projects was different from Asian colonies. This paper traces the origins of colonial approaches to irrigation development in Africa and the continuities between colonial and post-colonial approaches. The Kano River Project in Nigeria, part of a larger irrigation development program from the late 1960s and early 1970s, serves as a typical example of a post-colonial irrigation system in which engineers drew upon colonial experiences. The Dutch engineers responsible for developing the system applied technologies from the Netherlands East Indies to regulate water flows in the system. At the same time, they engaged in a debate on how to organize farmers in the project to ensure efficient and rational use of water in irrigated farming. They joined project managers in viewing strong control over farmer production – a central feature of African colonial irrigation projects – as key to success. However, given the social conditions in the Kano area, particularly landownership, this strong control proved difficult to realize.
-
Conceptualisation of the consequences of land use decisions on water resources in the central region of South Africa: an agent based modelling perspective
14 January 2011North West UniversityWoyessa, Y E;Welderufael, W A;Kinyua, J D MOver the past few decades, numerous researchers have improved measurements of land use change through representation of much more complex processes of land use and its impact on water resources. Understanding the causes of land use change has moved from a simplistic representation of a few driving forces to a much more detailed understanding that involves situation-specific interactions among a large number of factors at different spatial and temporal scales using agent-based models. The agentbased perspective is centred on the general nature and rules of land use decision making by individuals and represents the motivations behind decisions and the external factors that influence decisions about land use. In this paper, an attempt is made to conceptualise the social and biophysical interactions as the driving forces that lead to decisions of land use, and its potential impact on water resource, including factors such as interventions and technologies that influence the decision of land use change in rural agricultural areas. The development of the conceptual model was done through a series of meetings and workshops and by visualising the relationships between the different factors, such as biophysical and socio-economic factors, using a brain mapping technique. The resulting conceptual model illustrates the main domains of the environment, the socioeconomic factors, and captures all the factors and their interaction that lead to decision in land use change. The socio-economic factors and their interaction will be captured by the ABM module while the biophysical factors that have direct impact on runoff and stream flow could be handled by the hydrologic module which will then be integrated into the ABM model. This, however, is a primary effort in the development of an ABM within the Modder River Basin system and needs continues refinement for optimum functionality and simulation of the real world.
-
The tragedy of the water commons: the case of the Lower Orange water management area
14 January 2011North West UniversityGouws, C MIn the human environment there is a tendency to refer to resources, such as land and water which do not specifically belong to any single individual, as the ‘commons’. Garret Hardin wrote his famous paper called: “The Tragedy of the Commons” in which he highlighted the problem inhabitants of the world face regarding the growing population and depletion of natural resources. He proposed that limits must be placed on the liberal use of natural resources, which usually involve some kind of legislation. South Africa, as a semi-arid country, needs to manage the water as a commons to ensure that all inhabitants of the country have access to safe drinking water as instructed by the Constitution of the Republic of South Africa Act No. 108 of 1996 and subsequently preserved in the National Water Act No 36 of 1998. The significance of Hardin’s theory to South Africa becomes evident in the necessity of the mentioned acts, which involve the establishment of Catchment Management Agencies (CMAs) and Water User Associations (WUAs). These institutions must ensure the involvement of all stakeholders and water users to manage the resource optimally. Establishing these institutions, however, proved to be difficult and their efficiency questioned, thus illustrating a “tragedy within the tragedy”. This article considers the case of the Lower Orange Catchment Management Agency and the Upington Islands Water User Association in the //Khara Hais local municipality, to illustrate the thus far failing efforts taken by this region to manage the water resource.
-
Recent trends in South African water historiography
14 January 2011North West UniversityTempelhoff, J W NThe discipline of water history is relatively young but since the 1990s there has been growing interest in the field. In this article an exposition is provided on the origins of the discipline of water history as a subdivision of environmental history. The discussion then turns to an outline of recent developments in the historiography of water history in South Africa. Attention is also given to the possibility of extending the study of this discipline into a number of allied fields.
-
The devil is in the detail – an analysis of the DBSA’s ‘Access to Sanitation’ indicator
18 January 2011North West UniversityIngle, M KWhen using indicator values to measure change over an interval of time, the general understanding of the factor being analysed may have been modified during the period under review. Altered definitions of ‘urban’, or ‘poverty’, provide common instances of this phenomenon. This article outlines a similar situation with respect to the ‘access to sanitation’ indicator as it features in the Development Bank of Southern Africa’s series of Development Reports. These publications are often referred to as a ready source of useful information. It is shown how an altered understanding of what constituted ‘sanitation’ in South Africa came to influence the relevant indicator values. This change, if not taken into account, could result in planning calculations yielding invalid conclusions. The article deals with the casual use of ready-to-hand indicators by nonspecialist practitioners, and about how easy it is to be misled on occasion.
-
The role of science in deepening democracy: the case for water in post-Apartheid South Africa
19 January 2011North West UniversityTurton, ASouth Africa is a water constrained country with a complex history of resource capture and human rights abuses. Science, as practiced by the national science councils, could play a significant role in deepening our democracy. This paper explores two possible paradigms - one where science is divorced from the national constitution, and the other where our science is embedded in the national constitution. The paper argues that the latter approach would make our national science more relevant, but of necessity would embroil it in issues of historic legacy and therefore become “messy”.
-
Slow-onset disaster and sustainable livelihoods: the Vaal River in the vicinity of Parys
19 January 2011North West UniversityVan Riet, G;Tempelhoff, J W NThis article is based on data gathered during a research project commissioned by the Fezile Dabi District Municipality in the northern part of South Africa’s Free State Province. The research team (which included the authors) was asked to investigate allegations of pollution of tap water, as well as sewage from the local wastewater treatment plant flowing into the Vaal River in the town of Parys on the banks of the Vaal River. The authors adopt a sustainable livelihoods approach in analysing data gathered by way of unstructured interviews in and around Parys in June–July 2008. They argue that actual and perceived levels of pollution are eroding various local livelihood assets and it is posited that the situation constitutes an unfolding slow-onset disaster. It is imperative that shocks such as sewerage spills and rumours of polluted potable water are addressed to ensure that these do not become long-term negative trends.
-
Legal issues concerning mine closure and social responsibility on the West Rand
20 January 2011North West UniversityVan Eeden, Elize S;Liefferink, M;Durand, J FMining and, especially, gold and uranium mining have played a major role in the economy, history, and demography of South Africa. The contribution of the mines to the economy of South Africa over the past century has been overvalued, while the social injustices and negative environmental impacts that accompanied mining have been underplayed or ignored by the mining houses and government. The environmental situation has worsened significantly over the past few years due to the abandonment and pending closure of most of these mines. A reluctance is perceived on the part of the mining companies, and even government, to take responsibility for the damage caused by pollution, ecological degradation, and impact on human health by mining. Instead, the current informal policy appears to take smaller companies to court on minor environmental injustices to, perhaps, impress the broader public, while one of the biggest environmental concerns is stylishly treated. The inability of government to address the damage by mines effectively is in conflict with the National Water Act, the National Environmental Management Act, the Mineral and Petroleum Resources Act, the National Nuclear Regulator Act, and the Constitution of South Africa. The authors propose a multidisciplinary approach to address water-related environmental injustices on the West Rand and Far West Rand. We also describe the application of the National Environmental Management Act of South Africa (Act No. 107 of 1998) in the Wonderfonteinspruit and Tweelopiespruit Catchments and the current water quality situation.
-
Doddington Court: 160 Victoria Embankment, Durban.
05 January 2012North West UniversityFerreira, Philna• Opsomming: Doddington Court, met sy treffende steenwerkstruktuur, is sowel boeiend as amusant vanweë 'n eienaardige samevoeging van allerlei argitektoniese aspekte. Die ontwerp eerbiedig die inwoners se privaatheid, terwyl bekwame vakmanskap en deurgaanse deeglikheid opvallend is. Uiteenlopende dekoratiewe details is met oorleg geïntegreer. Die geheel bekoor vanweë die unieke sintese van styl en die aanwesigheid van eg-menslike elemente in hierdie tegnologiese eeu.
-
Parys on the Vaal.
09 January 2012North West UniversityOberholster, A G• Opsomming: Parys is in 1876 op die plaas Klipspruit aangelê. Die ontdekking van goud op die Witwatersrand in 1886 het baie vir die vooruitgang van die dorp beteken en in 1890 was dit een van die tien grootste dorpe in die OVS. Die Tweede Vryheidsoorlog het egter alle ontwikkeling tot stilstand gedwing. In 1905 is die spoorlyn na Parys voltooi en in 1910 is 'n dam in die Vaalrivier gebou wat die dorp se landboupotensiaal verhoog en watersportgeriewe geskep het. Verskillende nywerhede en sakeondernemings het mettertyd op die dorp gevestig geraak sodat Parys vandag 'n aantreklike en vooruitstrewende dorp met meer as 8 000 Blanke inwoners is.
-
Cape Town in 1829.
11 January 2012North West UniversityPhillips, H• Opsomming: Na die Britse besetting van die Kaap (1806) het die bevolking van die moederstad stadig toegeneem; teen 1829 was die inwonertal ruim 18000 en het bestaan uit invloedryke Engelse handelaars, Hollandssprekende persone, Vry Swartes en slawe. Onhigiëniese toestande het oor die algemeen geheers en gesondheidsdienste het veel te wense oorgelaat. Die lewensomstandighede van minder gegoede Blankes en die Vry Swartes was haglik en is vererger deur armoede, swak behuising, siektes en selfs epidemies. Deur Ordonnansie 50 van 1828 is die inheemse bevolkingsgroepe weliswaar met persone van Europese herkoms gelykgestel; die beginsel van integrasie was ook sosiaal aanvaarbaar. Tog was die gemeenskap nag op ʼn stelsel van slawerny aangewys en rassedifferensiasie in die samelewing was steeds merkbaar. Die handel en algemene vooruitgang is voorts deur ontoereikende hawegeriewe gestrem. Strate was stowwerig en onverlig, terwyl die oop waterkanale (gragte) vuil en ongesond was. In hierdie stadium het enkele klein woonbuurte (soos Seepunt en Wynberg) reeds bestaan; die plaaslike bestuur van Kaapstad was in die hande van die magistraat en amptenare war deur die regering aangestel is. ʼn Hooggeregshof is in die lewe geroep en tien advokate en elf prokureurs het teen 1829 in Kaapstad gepraktiseer. In teenstelling met die betreklik swak maatskaplike toestande, is ruim voorsien vir die opvoedkundige en godsdienstige behoeftes van die inwoners. Ook die kulturele lewe aan die Kaap was lewendig en ontspanningsgeriewe redelik goed. Teen 1829 was Kaapstad inderdaad besig om, veral onder die invloed van Britse immigrante, ʼn nuwe vorm aan te neem.
-
Through Livingstone’s eyes: perspectives on water in nineteenth-century Southern Africa (1849-56)
19 January 2012North West UniversityTempelhoff, Johann W N• Opsomming: David Livingstone (1813–1873) was deel van ‘n merkwaardige geslag ontdekkingsreisigers wat in die negentiende eeu Afrika vir die Engelssprekende wêreld oopgestel het. In Missionary travels and researches in South Africa (1858), ‘n klassieke reisbeskrywing, maak hy onder meer telkens mededelings aan mense in Brittanje en Noord-Amerika in verband met die wyse waarop hy die wateromgewing in suider-Afrika ervaar het terwyl hy op reis was in die streek. Livingstone se waarnemings werp waardevolle lig oor die wyse waarop inheemse gemeenskappe met die wateromgewing omgegaan het. Ook is daar aanduidings van die wyse waarop hulle die beskikbare waterbronne bestuur het. Ook word kennis geneem van Victoriaanse perspektiewe oor water in suider-Afrika.
-
Progress towards legislative transformation: a critical assessment of the 1956 and 1998 water acts regarding municipal water supply.
20 January 2012North West UniversityNealer, Eric J.;Raga, Kishore• Opsomming: Inwoners van Suid-Afrika behoort deurlopend herinner te word dat hulle ‘n waterarmland bewoon en dat kennis oor die fisiese omgewing en die aard en omvang van effektiewe openbare bestuur van watervoorsiening van strategiese belang is. Die oppervlakte- en grondwater wat in die rivieropvanggebiede saamvloei is hidrologies en geohidrologies verbind deur die hidrologiese kringloop. Laasgenoemde manifesteer in ‘n natuurlike omgewing wat nie net gekenmerk word deur ‘n toestand van wye diversiteit en kompleksiteit nie, maar ook deur die behoefte aan goed gestruktureerde openbare dienslewering op veral die plaaslike regeringsfeer. Teen die einde van April 1994 was die voorsiening van openbare drinkwater en basiese sanitasiedienste aan al die landsinwoners op al die owerheidsfeer- en veral die plaaslike regeringsfeeragendas die hoogste in die openbare diens geskiedenis van Suid-Afrika. Gevolglik is die Regering nie net meer gemoeid met die verskaffing van genoegsame drinkwater alleen nie, maar ook met die fasilitering van die implementering van ‘n holistiese en geïntegreerde benadering aangaande die effektiewe, doeltreffende en ekonomiese bestuur van die ontwikkeling, vervoer, opgaar, behandeling en verspreiding van water. As die enigste bestuurder en bewaarder van die land se waterbronne is die Departement van Waterwese en Bosbou (DWAF) sedert veral die oorgang na ‘n demokratiese bestel in 1994 proaktief in die evaluering van bestaande beleidsdokumente sowel as die voortbring van verbeterde wette en uitvoerbare openbare beleid aangaande waterbestuursaspekte in die land. Dit is ook opmerklik dat primêre nasionale wetgewing aangaande die bestuur van openbare water sedert die 1956 - en die jongste 1998 waterwetgewing transformasie ondergaan het en dat die mees optimale voertuig tot meer effektiewe, doeltreffende en ekonomiese implementering van die nuwe getransformeerde openbare waterverwante wetgewing die 284 munisipaliteite in die land is. Dit is dan ook op hierdie regeringsfeer waar die spreekwoordelike ‘motorkarwiel die teerpad tref’ en die sukses al dan nie, van nuut geïmplementeerde openbare beleid evalueer kan word. Die fokus van die artikel is om vanuit ‘n dissiplinêr geïntegreerde perspektief die toepassing van watergewing in Suid-Afrika op munisipale owerheidsfeer krities in oënskou te neem.
-
Challenges associated with living in karst environments, such as the historical Cradle of Humankind.
23 January 2012North West UniversityDurand, J FrancoisDie unieke geologiese aard van die Wieg-van-die-Mens-Wêrelderfenisgebied (Cradle of Humankind) noord van Krugersdorp, bied sekere uitdagings vir die mense wat daar woon en werk. Hierdie gebied vorm deel van ‘n reuse dolomitiese afsetting wat deur verwering, hoofsaaklik deur die werking van water, in ‘n tipiese karstlandskap verander is gekenmerk deur grotte, sinkgate, ondergrondse mere en akwifere. Karstsisteme bied skuiling aan ‘n verskeidenheid organismes soos grotwonende vlêrmuise en grondwaterwonende amfipode. ‘n Baie spesifieke ekotoon tussen die suidelike grasveld en noordelike bosveld wat deur ‘n unieke versameling silwerblaar plante gekenmerk word kom in hierdie gebied voor. Benewens hierdie belangrike biologiese aspekte, is hierdie gebied wêreldbekend vir sy ongeëwenaarde fossielrykdom. Die onoordeelkundige gebruik van hulpbronne binne hierdie gebied kan onherstelbare skade aan hierdie unieke erfenis berokken. Besoedeling van die grondwater wat die enigste drinkwater in die gebied is, kan ernstige gesondheidgevare vir die inwoners van hierdie gebied inhou. ‘n Opvoedkundige program oor die bewaring van die karstsisteem, gemik op volwassenes sowel as kinders, geletterdes en ongeletterdes wat in hierdie gebied woon en werk kan tot die volhoubare benutting en bewoning van hierdie gebied lei. ‘n Kundige bevolking sal ook bewus wees van negatiewe antropogeniese impakte wat die karstsisteem vanuit die aangrensende gebiede mag bedreig, en kan met die hulp van die owerhede teen diesulke oortreders optree.
-
Conflicting perceptions over water distribution in Sibasa-Thohoyandou area: interpreting local narratives.
23 January 2012North West UniversityWuriga, RabsonThe state perceives water as an economic commodity, even if its existing policy treats it as a national resource that should be freely accessed for basic usage. Research suggests many residents of the Sibasa-Thohoyandou area in the Limpopo Province, perceive water as a free natural resource that should not be paid for. As a result of this perception, most of the local residents are not paying for water services. In response to that, the municipality is faced with a cost-recovery problem – hence they restrict water reticulation. Residents concede that paying is a last resort because they are in need of water. Research was conducted on this issue after it surfaced as an apparent problem in the local media. The article explores and attempts to interpret the conflicting narratives on water procurement and distribution in the Sibasa-Thohoyandou area.