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Ntshingila, Sincengile Nokubonga. "Domestic water uses and value in Swaziland a contingent valuation approach /." Diss., Pretoria : [s.n.], 2006. http://upetd.up.ac.za/thesis/available/etd-02192007-171458.
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Thesis (M. Sc.(Agric))(Agricultural Economics)--University of Pretoria, 2006.Includes summary. Includes bibliographical references (leaves 81-95). Available on the Internet via the World Wide Web.
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Yohannes, Gebre Michael. "The use, maintenance and development of soil and water conservation measures by small-scale farming households in different agro-climatic zones of Northern Shewa and Southern Wello, Ethiopia /." [S.l.] : [s.n.], 1999. http://www.ub.unibe.ch/content/bibliotheken_sammlungen/sondersammlungen/dissen_bestellformular/index_ger.html.
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Krantz, Helena. "Matter that matters : A study of household routines in a process of changing water and sanitation arrangements." Doctoral thesis, Linköping : Dept. of Water and Environmental Studies, Univ, 2005. http://www.ep.liu.se/diss/arts_science/2005/316/index.html.
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Barnett, Matthew J. "A Multilevel Analysis of Social, Built, and Natural Drivers of Household Water Use in Northern Utah." The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1524163716518209.
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Breyer, Elizabeth Yancey. "Household Water Demand and Land Use Context: A Multilevel Approach." PDXScholar, 2014. https://pdxscholar.library.pdx.edu/open_access_etds/1670.
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Urban water use arises from a mix of scale-dependent biophysical and socioeconomic factors. In Portland, Oregon, single-family residential water use exhibits a tightly coupled relationship with summertime weather, although this relationship varies with land use patterns across households and neighborhoods. This thesis developed a multilevel regression model to evaluate the relative importance of weather variability, parcel land use characteristics, and neighborhood geographic context in explaining single-family residential water demand patterns in the Portland metropolitan area. The model drew on a high-resolution panel dataset of weekly mean summer water use over five years (2001-2005) for a sample of 460 single-family households spanning an urban-to-suburban gradient. Water use was found to be most elastic with respect to parcel-scale building size. Building age was negatively related to water use at both the parcel and neighborhood scale. Half the variation in water use can be attributed to between-household factors. Between-neighborhood variation exerted a modest but statistically significant effect. The analysis decomposed household temperature sensitivity into four components: a fixed effect common to all households, a household-specific deviation from the fixed effect, a separate extreme heat effect, and a land use effect, where lot size exaggerated the effect of temperature on water use. Results suggested that land use planning may be an effective non-price mechanism for long-range management of peak demand, as land use decisions have water use implications. The combined effects of population growth, urbanization, and climate change expose water providers to risk of water stress. Modeling fine-grain relationships among heat, land use, and water use across scales plays a role in long-range climate change planning and adaptation.
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Tellez, Sanchez Sarita Lucia. "Household Water Filter Use Characterization in Rural Rwanda: Signal Interpretation, Development and Validation." PDXScholar, 2016. http://pdxscholar.library.pdx.edu/open_access_etds/3026.
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Access to safe drinking water is an important health factor in many developing countries. Studies have shown that unsafe drinking water and poor sanitation practices leads to diarrheal disease, which is one of the leading causes of death of children under five in developing countries. Provision and proper use of household water filters have been shown to effectively improve health.
This thesis is focused on the refinement and validation of algorithms for data collected from pressure transducer sensors that are used in household water filters (the Vestergaard Frandsen LifeStraw Family 2.0) deployed in Rwanda by the social enterprise DelAgua Health. Statistical and signal processing techniques were used to detect the use of the LifeStraw water filters and to estimate the amount of water filtered at the time of usage. An algorithm developed by Dr. Carson Wick at Georgia Institute of Technology was the baseline for the analysis of the data. The algorithm was then refined based on data collected in the SweetLab at Portland State University, which was then applied to field data.
Laboratory results indicated that the mean error of the improved algorithm is 11.5% as compared with the baseline algorithm mean error of 39%. The validation of the algorithm with field data yielded a mean error of 5%. Errors may be attributed to real-world behavior of the water filter, electronic noise, ambient temperature, and variations in the approximation made to the field data. This work also presents some consideration of the algorithm applied to soft-sided water backpacks.
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Parker, Joanne. "Assessing the sensitivity of historic micro-component household water-use to climatic drivers." Thesis, Loughborough University, 2014. https://dspace.lboro.ac.uk/2134/14939.
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Anthropogenic climate change is arguably the greatest challenge of modern times posing significant risks to natural resources and the environment. Socio-economic change, severe droughts, and environmental concerns focus attention upon sustainability of water supplies and the ability of water utilities to meet competing demands worldwide. The 2012 Climate Change Risk Assessment identified water security as one of the most significant climate threats facing the UK. It is now recognised that household water demand management could offer a low regret adaptation measure (both financially and environmentally) given large uncertainties about future climate and non-climatic pressures. This thesis uses Anglian Water Services (AWS) Golden 100 dataset to explore the climate sensitivity of historic micro-component water-use. This work contributes to a larger integrated assessment of the South-East England water system under the EPSRC Adaptation and Resilience to a Changing Climate Coordination Network (ARCC CN). The Golden 100 is a metered record of 100 households daily water consumption by basin, bath, dishwasher, external, kitchen sink, shower, WC and washing machine use. The archive also includes socio-economic information for each household, dates of the year and daily time series of observed minimum temperature, maximum temperature, sunshine hours, soil moisture deficit, concurrent, and antecedent rainfall amounts. The methodology developed within this research provides a portable approach to error trapping, formatting and mining large, complex water sector datasets, for exploring the relative sensitivities of micro-component metered water-use to weather/non-weather variables. This research recognises both the importance of the choice to use a micro-component and the volume used. As such, logistic and linear generalised regression techniques are employed to explore the relative sensitivity of these two aspects of water-use to climatic and non-climatic variables. The 2009 UK Climate Projections (UKCP09) projections and climate analogues are then used to bound a climate sensitivity analysis of the most weather-sensitive micro-components using temperature and rainfall scenarios for the 2050s and 2080s. This research provides empirical evidence that the most weather sensitive micro-components are external and shower water-use. A key contribution of this research to existing knowledge is the non-linear response of likelihood and volume of external water-use to average air temperatures. There is an abrupt increase in the likelihood of external water-use on days above ~15??C. Climate sensitivity analysis further suggests that by the 2080s, under a hotter/drier climate, average unmetered households could be 8% more likely to use external-water and expend ~9 litres more per day during the summer. For the same parameters, high water users (defined here as the 90th percentile) could consume ~13 litres more external water per day. Importantly, this research has re-affirmed the relative importance of behavioural drivers of water-use as manifested by pronounced day of week and bank holiday signatures in both the likelihood and volume of use statistics. As such, this prompts future studies and water management efforts to consider the impact of behavioural drivers as well as climate. It must be recognised that the small sample size of the Golden 100 combined with the Hawthorn effect, self-selection and sample biases in factors such as socio-economic status, billing method and occupancy rate all limit the sample representativeness of the wider population. As such, any predictions based on the data must be treated as illustrative rather than definitive. Furthermore, the results are probably specific to the demographic and socio-economic groups comprising the sample. Nonetheless, this research sheds new light into water-use within the home thereby adding value to a dataset that was not originally collected with household-level, weather-related research in mind.
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Vanderzwaag, Jason Corey. "Use and performance of BioSand filters in Posoltega, Nicaragua." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/738.
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An evaluation of BioSand Filters, a method of Household Water Treatment, was conducted in Posoltega, Nicaragua, with objectives of determining the long-term filtration efficiency and the rate of sustained use. Field methods included microbial and turbidity water quality testing and interviews with filter users regarding the operation, maintenance and perceptions towards the filters. Of the 234 BioSand Filters installed in 1999 and 2004, only 24 were found to still be in operation. The average filtration efficiency was found to be 98% for total coliforms, 96% for E. coli and 88% for turbidity. Statistically significant effects on filtration efficiency were detected for the source contamination, the inverse of the flow rate, and the standing depth of water over the sand.
A follow-up laboratory QA/QC procedure was undertaken to validate the field methods, which consisted of membrane filtration (MF) with m coliBlue24 growth media, and SolarCult dipslides. It was found that MF with m coliBlue24 produced useful reproducible results, and is an appropriate method for conducting field water quality testing. The dipslides were found to be an appropriate tool for testing source water quality and assessing the applicability of BioSand Filters, and may be an appropriate tool for local health representatives to promote safe water practices within the community. However, the dipslides should not be used as a presence / absence test for drinking water due to the high limit of detection.
The low rate of sustained use (10%) is mostly a result of the structural failure of the concrete walls of the filter, in particular for those filters from 2004. Anecdotal evidence suggests insufficient quality control during the construction. The filtered water and the stored post-filtered water did not meet the WHO guidelines for safe drinking water on account of the presence of E. coli. Also identified were improper maintenance practices and unsafe storage of post-filtered water. These problems could have been addressed through the development of a holistic water system approach, such as the World Health Organization Water Safety Plan.
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Matikinca, Phikolomzi. "Exploring impacts and effectiveness of the City of Cape Town’s interventions on household water use practices during the drought." Master's thesis, Faculty of Science, 2019. http://hdl.handle.net/11427/31599.
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The occurrence of water crises in many parts of the world raises the need to consider more efficient and sustainable consumption of water resources. As such, many cities have prioritised water demand management strategies, which are based on price and non-price mechanisms. The literature shows no consensus as to which of these measures are most effective for managing residential water demand. To understand the impact and effectiveness of these mechanisms, there is a need to understand how people respond to them. This requires understanding materials, meanings and competences (skills and know how) that people have, which constitute elements of social practice. In 2017 and 2018, the City of Cape Town (CoCT) ramped up their price and non-price mechanisms to encourage people to save water in response to a severe drought. These mechanisms included water restrictions, increased water tariffs, and the Day Zero communication campaign. However, little is known about how effective these measures were at encouraging people to save water. There is no clear documentation of how the public understands, interprets and incorporates these mechanisms into their own household water use practices. This study explores the impacts and effectiveness of the City of Cape Town’s price and non-price mechanisms on household water use practices during the water crisis. Using information obtained through semi-structured interviews with 20 individuals living in houses where they paid their water bills, a version of social practice theory is used as a lens to understand how respondents interpreted and responded to these mechanisms when it comes to residential water use practices. This allows for an assessment of which of the CoCT’s actions are more effective in achieving sustainable water use practices. Results show that price mechanisms (water tariffs) were considered to be ineffective and did not encourage people to save water. Non-price mechanisms (water restrictions and Day Zero communication campaign) were seen as having more impact on respondents, encouraging water conservation behaviour; especially when it comes to household indoor water use activities related to hygiene. Compared to other studies which have used estimates for the water demand function, this study conducted interviews directly with households on the impact of the mechanisms. This enabled this study to explain how and why household water use practices change in response to these measures. Such qualitative information is important and contributes to a field that often uses quantitative data to suggest whether price or non-price mechanisms are effective.
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Jeffreys, Kendralyn G. "A Survey of Point of Use Household Water Treatment Options for Rural South India." Digital Archive @ GSU, 2012. http://digitalarchive.gsu.edu/iph_theses/190.
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Contaminated drinking water is one of the major health challenges facing people in the developing world. The country of India leads the world in under age five mortality due to diarrheal disease, which is attributed to water and food contamination. While the Indian government has made progress in expanding access to improved water sources in the last decade, the microbiological quality of the water is unpredictable. Point of use household water treatment systems can provide clean drinking water for people who do not have access to a clean water source. This report examines five non-electrical point of use household water treatment options which have been extensively field-tested and could potentially be used in rural, South Indian villages: chlorine disinfectant, chlorine-flocculant sachets, ceramic filters, biosand filters and solar disinfection. A case study of a village in Andhra Pradesh is presented that highlights the factors to consider when introducing a new POU technology into a community.
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Stevenson, Matthew M. "Monitoring effective use of household water treatment and safe storage technologies in Ethiopia and Ghana." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/47783.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, February 2009.Includes bibliographical references (p. 117-125).
Household water treatment and storage (HWTS) technologies dissemination is beginning to scale-up to reach the almost 900 million people without access to an improved water supply (WHO/UNICEF/JMP, 2008). Without well-informed and effective use as intended, these promising technologies will not be deployed to maximum advantage. Successful scale-up thus requires monitoring and evaluation (M&E) of behavioral indicators to achieve safe water and improved health. This thesis offers a consistent framework for the operational monitoring of Effective Use of a set of eight HWTS technologies including dilute bleach solution, Aquatabs, solar disinfection (SODIS), cloth filters, the ceramic pot filter, the biosand filter, PUR and associated safe storage practices. During late 2007, key members of the WHO-hosted International Network to Promote Household Water Treatment and Safe Storage ("The Network") who are involved with M&E of HWTS systems were contacted. A literature search on monitoring efforts involving the eight HWTS followed. The author traveled to Ethiopia and Ghana during January 2008 to investigate multiple HWTS implementations and field-test preliminary monitoring methods as part of that process. Interviews were conducted with HWTS Network partners and the users of their HWTS products, household water quality testing was conducted, and documents on usage and monitoring were collected and compiled. A framework for operational monitoring of Effective Use behaviors at the household was developed through these efforts. The framework consists of a set of Monitoring Observations specific to each technology, comprised of the five categories of Treatment, Safe Storage, Maintenance, Replacement Period, and Physical Inspection, as well as a set of common Water Quality Monitoring paramaeters.
(cont.) Field methods for measuring turbidity, residual free available chlorine, and E.coli as an indicator of microbiological water quality are described that require minimal training, time, and equipment and that are cost-effective (US $3.60 for a complete set of household tests).
by Matthew M. Stevenson.
M.Eng.
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Putnam, Merril Augusta. "Insight into the Use, Perception, and Value Surrounding Domestic Water in Peru: Envisioning Demand Management in an Intermittent, Small-City, Service Context." Scholar Commons, 2013. http://scholarcommons.usf.edu/etd/4750.
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Population growth, urbanization, degrading water quality, and climate change are making management of scarce water resources an increasingly difficult task for the domestic sector. It is recognized that in order to manage urban water resources demand management is requisite. Demand management has been experimented with in large cities of developing countries but continued focus on expanding supply overshadows its potential benefits and ultimate success. In order to manage demand, it must be measured and understood. Intermittent water services are prevalent in developing countries, but unmetered domestic water use under such conditions has not been carefully studied. This study conducted 1,149 household surveys in a small, growing, coastal city (population est. 35,645) in La Libertad, Peru. The objectives were to 1) characterize current household water use behaviors, perceptions and values as they vary among three user groups (two distinct unmetered intermittent water services and well users) and reveal the existing water use and potential household demand for water, and 2) propose demand management tactics applicable to conditions of the study site that may be generalizable to small, developing, cities. Survey results show daily per capita water use in the range of 35 to 90 L with more water being used by the group that receives water for a longer duration of time. The distribution of water was inequitable and, on average, households received water for less time than the service providers' reported duration. Demand is likely to grow due to increasing water-related infrastructure, established water behaviors, and a lack of understanding regarding regional scarcity and water conservation. Households are not satisfied with existing service conditions, particularly water quality, but due to an apparent distrust in their water providers are unwilling to pay for improvements. For domestic service to remain sustainable under the pressures of increasing water scarcity, demand management strategies, particularly education and awareness building, are likely achievable and should be adopted, complementary to supply-minded management.
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Paynter, Nathaniel Collingwood Gooch 1971. "Household water use and treatment practices in rural Nepal : BioSand evaluation and considerations for future projects." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/84284.
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Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2001.Includes bibliographical references (leaves 78-81).
by Nathaniel Collingwood Gooch Paynter.
M.Eng.
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Mohamed, Farzana S. 1977. "Household-level point-of-use water filtration system in Haiti : strategies for program management and sustainability." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/39400.
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Thesis (M.C.P.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning; and, (M.Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2001.Includes bibliographical references (p. 30-33).
The traditional approach of providing safe drinking water supplies through centralized large-scale systems has proven ineffective, costly, and elusive, particularly in serving the needs of rural populations in developing countries. The focus of safe water provision in developing countries is steadily shifting to the use of a body of smaller-scale point-of-use technologies, in which water is treated by its end user, that are cheaper, more appropriate for such contexts, and locally controlled. Oift of Water, Inc., (OWl), is a Florida-based non-profit organization that has been developing and implementing point-of-use household-level water purification projects in Haiti since its inception six years ago. In addition to providing seven Haitian communities with inexpensive point-of-use treatment systems for use in individual homes, OWl trains and actively supports a network of community technicians who are responsible for monitoring and troubleshooting filter programs, and for educating community members in the use of OWl's systems. This thesis reviews the development of OWl's programs in Haiti, recommends strategies for program management, and suggests mechanisms for ensuring program sustainability.
by Farzana S. Mohamed.
M.Eng.
M.C.P.
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Carpenter, Jacob Daniel. "An Assessment of the EMAS Pump and its Potential for Use in Household Water Systems in Uganda." Scholar Commons, 2014. https://scholarcommons.usf.edu/etd/4996.
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Rural improved water supply coverage in Uganda has stagnated around 64% for a number of years and at this point more than 10 million rural people do not have access to an improved drinking water source. It has been recognized that progress toward improved water supply coverage and increased service levels may be gained through Government and nongovernmental organization (NGO) support of private investment in household and shared water supplies, commonly known as Self-supply. Self-supply can be promoted by introducing and building local capacity in appropriate and affordable water supply technologies such as hand-dug wells, manually drilled boreholes, low-cost pumps, and rainwater harvesting. Support can also be focused on technical support, marketing, financing, and strategic subsidies that promote and enhance user investment. The Uganda Ministry of Water and Environment has embraced Self-supply as a complementary part of its water supply strategy while government and NGO programs that support Self-supply have emerged.
The EMAS Pump is a low-cost handpump appropriate for use in household water systems in the developing world. There are more than 20,000 in use in Bolivia, with many constructed through Self-supply. The EMAS Pump is constructed from simple materials costing about $US 10-30, depending largely on installation depth, and can be fabricated with simple tools in areas with no electricity. The EMAS Pump is used with low-cost groundwater sources such as hand-dug wells and manually drilled boreholes or with underground rainwater storage tanks. It can lift water from 30 m or more below ground and pump water with pressure overland
or to an elevated tank. The objectives of this research were to conduct an assessment of the EMAS Pump that considers pumping rates, required energy, and associated costs, to characterize the EMAS Pump for its potential for use in household water systems in Uganda, and to make relevant recommendations.
The potential of the EMAS Pump was assessed through testing its use with 2 subject participants (male and female) on wells of 5.1 m, 12.6 m, 17.0 m, 18.4 m, 21.1 m, and 28.3 m static water levels as part of a side-by-side comparative assessment with the Family Model version of the Rope Pump, a more widely known low-cost handpump that has recently been introduced and promoted in Uganda. Shallow and deep versions of each pump were tested on selected wells for 40-liter pumping trials. The status and feasibility of low-cost groundwater development and underground storage tanks were also explored in order to help characterize the potential of the EMAS Pump as an option for low-cost household water systems in Uganda.
In general, it was observed that the EMAS Pump performed comparably to the Rope Pump in terms of pumping rates for shallow depths, but the Rope Pump outperformed it on deeper wells. It was determined that the EMAS Pump required more energy for pumping during nearly all trials. A study of relevant supply chains in Uganda concluded that the EMAS pump has a material cost that is less than 50% of the Rope Pump for most applications and 21% of the cost for shallow wells. It was also determined that the EMAS Pump could feasibly be produced nearly anywhere in the country. There are indications that low-cost wells and underground rainwater tanks are applicable in many parts of Uganda and could be paired with an EMAS Pump to achieve significant affordability for Self-supply household water systems. Recommendations are provided in terms of the feasibility of introducing the EMAS Pump as a part of Self-supply strategy in Uganda.
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James, Ryan. "Agent-Based Model to Manage Household Water Use Through Social-Environmental Strategies of Encouragement and Peer Pressure." DigitalCommons@USU, 2019. https://digitalcommons.usu.edu/etd/7581.
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Inelastic price responses, demand hardening, and poor public awareness reduce the effectiveness of demand side strategies on water savings. This project quantified phycological household’s factors of attitudes, peer support, opportunities on water conservation with two social-environmental management strategies of encouragement and peer pressure. An agent-based model was populated with data for Logan, Utah using surveys, municipal billing, aerial imagery, weather monitoring stations, and flow, frequency, and durations of appliance use data. Results indicated those households with higher attitudes, peer support and opportunities saved the most water while peer pressure saved more than encouragement when using small and diverse social networks that could better regulate the behavior of outlier households within the network. Combined peer pressure and encouragement saved the most water as each strategy complimented one other. Managers can use results to identify and target large use households. Managers should recommend opportunities to conserve water through monthly bills and provide platforms for households to share their water use stories and information with each other.
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O'Connell, Bethesda, Deborah Slawson, Megan Quinn, Phillip R. Scheuerman, and Olushola Ogunleye. "Biosand Water Filter Evaluation: Pilot Study of Field Use Indicators in Cyegera, Rwanda." Digital Commons @ East Tennessee State University, 2018. https://dc.etsu.edu/etsu-works/5481.
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Diarrheal diseases are a global public health burden, killing 1.8 million people annually. Diarrhea disproportionately affects children and those in poverty. Most diarrheal cases can be prevented through safe drinking water, basic hygiene and/or sanitation measures, with drinking water interventions having the most impact on reducing diarrheal disease. There is no generally agreed-upon field method for determining biosand water filter effectiveness that is usable in low-resource communities. A pilot study was conducted of potential field use indicators, including the Colilert coliform presence/absence (P/A) test, hydrogen sulfide, alkalinity, hardness, pH, and fluorescently labeled latex microspheres. The study included both laboratory and field testing. The Colilert P/A test had the highest correlation to the United States Environmental Protection Agency standard method (IDEXX Quanti-trays), but more data are needed before making a recommendation. This study adds to understanding about evaluation of biosand water filters and provides preliminary data to address the need for a field use indicator for biosand water filters.
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O'Connell, Bethesda, Deborah Slawson, Megan Quinn, Phillip Scheuerman, and Olushola Ogunleye. "Biosand Water Filter Evaluation: Pilot Study of Field Use Indicators in Cyegera, Rwanda." Digital Commons @ East Tennessee State University, 2018. https://dc.etsu.edu/etsu-works/5588.
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Diarrheal diseases are a global public health burden, killing 1.8 million people annually. Diarrhea disproportionately affects children and those in poverty. Most diarrheal cases can be prevented through safe drinking water, basic hygiene and/or sanitation measures, with drinking water interventions having the most impact on reducing diarrheal disease. There is no generally agreed-upon field method for determining biosand water filter effectiveness that is usable in low-resource communities. A pilot study was conducted of potential field use indicators, including the Colilert coliform presence/absence (P/A) test, hydrogen sulfide, alkalinity, hardness, pH, and fluorescently labeled latex microspheres. The study included both laboratory and field testing. The Colilert P/A test had the highest correlation to the United States Environmental Protection Agency standard method (IDEXX Quanti-trays), but more data are needed before making a recommendation. This study adds to understanding about evaluation of biosand water filters and provides preliminary data to address the need for a field use indicator for biosand water filters.
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Omisca, Erlande. "Environmental Health in the Latin American and Caribbean Region: Use of Water Storage Containers, Water Quality, and Community Perception." Scholar Commons, 2011. http://scholarcommons.usf.edu/etd/3269.
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Water quality and availability are important issues in many developing countries where portions of populations still lack access to potable water. Throughout the English-speaking Caribbean and parts of Latin America, households and businesses invest in water supply systems even when they are connected to and pay for water services from a private or state owned provider. Inconsistent supplies of water from the water companies have led many people to invest in storage tanks which, if operated correctly, can provide water throughout the day even when the supply from the main is low or zero. While these individual systems help to guarantee a more constant supply of water, they may impact water quality when it does reach the household tap. The tanks could become breeding grounds for vectors of human disease and may also affect the concentrations of bacteria, heavy metals and organics in the water.
The goal of this research was to understand how households use water storage tanks and determine the effect of these tanks and the individual practices on water quality. Target plots were used to visualize linkages between water quality parameters and household surveys of localized water practices and perception on water quality.
The study focused on three field sites: Siparia, Trinidad and Tobago, Region 4 Subset in Guyana, and Villa Litoral, Bolivia. Convenience sampling was used to administer surveys to households in the rural areas of Siparia (39), Region 4 Subset (40), and Villa Litoral (57). The Region 4 Subset is comprised of two rural areas, Mon Repos and Mocha, and Georgetown, the country's capital.
Black, high-density polyethylene (HDPE) tanks and water storage drums are predominantly used in the field sites within Siparia and Region 4 Subset, while cement tanks, drums, and jerry cans are used in Villa Litoral. The average age of household water storage devices was 4-10 years in Siparia and Region 4 Subset, and 0- 3 years in Villa Litoral. These devices were found on various elevations to accommodate piped connection, indoor pumping, and rainwater catchment. Cleaning frequency of tanks in Siparia was every few months, while in Region 4 Subset it varied from weekly to every few months. In Villa Litoral 26.3% of the population surveyed cleaned weekly and 38.6% cleaned annually. Disinfection of water sources was practiced by 30% of residents in Siparia and 60% of residents in the Region 4 Subset. While disinfection was practiced, issues with frequency and correct dosage led to inadequate disinfection. Eighty-four percent of households in Siparia and 50% of households in Region 4 Subset disinfected on a monthly or quarterly basis. Of the households that did disinfect, the bleach and/or disinfectant used was allowed to mix for at least 30 minutes in 50% of households in Siparia and 91.6% of households in the Region 4 Subset. Disinfection was not practiced by the majority of households in Villa Litoral. With regards to health, 15% of households in Region 4 Subset and 40.4% in Villa Litoral reported recent waterborne illnesses among house members.
Water samples were taken from households in Siparia (24), Region 4 Subset (40), and Villa Litoral (26). The majority of households in all three communities relied on piped water from their respective main pump. Those who were not connected to piped water relied on rain water. In the Region 4 Subset, 18% of samples tested positive for fecal coliform and 45% for total coliform. In Villa Litoral, 85% of samples tested positive for fecal coliform and 100% for total coliform. The majority of samples from all three communities exceeded the WHO guideline values for lead (0.01 mg/L) and iron (0.3 mg/L). This was most likely due to the material used in the household plumbing and distribution pipe infrastructure as these could leach.
Five indicators (chemical and biological water quality, reach of risk, storage device, female involvement, and household belief) were conveniently projected on target plots to link the results from water quality assessments with reported household practices and beliefs. The greatest risk factors seen were poor water quality and household beliefs like the security of water storage containers and safety of stored water, perceived water description and pressure, and access to water safety media.
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Clopeck, Katherine L. (Katherine Lorraine). "Monitoring and evaluation of household water treatment and safe storage technologies : the sustained use of the KOSIM ceramic water filter in northern region Ghana." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/51653.
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Thesis (S.M. in Technology and Policy)--Massachusetts Institute of Technology, Engineering Systems Division, Technology and Policy Program, 2009.Includes bibliographical references (p. 120-123).
Today, approximately 884 million people lack access to an improved drinking water (WHO and UNICEF, 2008). According to the World Health Organization (WHO), contaminated water and poor sanitation cause 30,000 deaths worldwide each day (WHO and UNICEF, 2008). Household drinking water and safe storage (HWTS), is a new health intervention that enables people to treat water in their own homes. Today, hundreds of non-profit organizations, for-profit business, social enterprises, academic institutions, faith-based organizations and governments are working around the world to promote HWTS technologies, especially to those people most in need. This thesis uses Pure Home Water (PHW), a small non-profit in Northern Region Ghana, as a case study to evaluate the use of a widespread HWTS technology, the ceramic pot filter. During the months of January, June and July 2008, I surveyed 309 of Pure Home Water's rural customers who had purchased a KOSIM filter between 2005 and 2008 to determine both the sustained use of the KOSIM ceramic pot filter and the factors that contribute to sustained use or disuse. I also conducted water quality analysis using the Colilert® and the 3MTM PetrifilmTM tests to evaluate the performance of the KOSIM filter in the field. Forty-six percent of PHW's rural customers were still using the KOSIM ceramic pot filter at the time of the interview. The survey results indicated that household income, reported water source, and the price paid for the filter are each associated with sustained use or disuse of the KOSIM filter.
(cont.) The average total coliform (TC) and E.coli counts for KOSIM-filtered water using the lower test detection limit of the 3MTMPetrifilmTM/Colilert® test combination were 323 CFU/100 mL and 7 CFU/100 mL respectively, which corresponds to a "low" risk level (WHO, 1997). The average TC and E.coli counts for KOSIM-filtered water using the upper test detection limits increased to 1,097 CFU/100 mL and 37 CFU/mL respectively. These results correspond to an "intermediate" risk level (WHO, 1997). On average, the KOSIM water filter removes 96.2% of TC (1.42 log reduction) and 89.2% (0.99 log reduction) of E.coli using the lower test detection limit. The average TC and E.coli reductions using the upper test detection limits are 88.8% (0.95 log reduction) and 82% (0.75 log reduction) respectively. Key Words: monitoring and evaluation, household water treatment and safe storage, household surveys, ceramic filter, sustained use, Millennium Development Goals, Ghana, Pure Home Water
by Katherine L. Glopeck.
S.M.in Technology and Policy
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Rameck, Makokove. "Determining the association between household drinking water handling practices and bacteriological quality of drinking water at the point-of-use in the rural communities of Murewa district, Zimbabwe." University of the Western Cape, 2018. http://hdl.handle.net/11394/6859.
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Magister Public Health - MPHThere is growing awareness that drinking water can become contaminated following its collection from safe communal sources such as boreholes, as well as during transportation and storage in the house. Drinking water is the most important source of gastroentric diseases worldwide, mainly due to post collection contamination of drinking water. Globally, waterborne diseases are a major public health problem, causing millions of deaths annually. Aim: To determine the association between household drinking water handling practices and bacteriological quality of drinking water at the point-of-use in the rural communities of Murewa district in Zimbabwe.
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Reygadas, Robles Gil Fermin. "User Compliance, Field Efficacy, and Greenhouse Gas Emissions of an Ultraviolet Water Disinfection System and other Drinking Water Treatment Alternatives for Rural Households in Mexico." Thesis, University of California, Berkeley, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3685996.
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Many households in developing countries rely on contaminated and untreated drinking water sources, contributing to gastrointestinal illness and other health risks. Even piped water quality is often unreliable because of poorly-maintained treatment or distribution systems. Household water treatment (HWT) systems aim to enable users to treat their water at the point of use, making it safe to drink. While some HWT options have been successful in improving health in developing countries, low adoption and sustained use outside pilot projects and epidemiological trials remains one of the current challenges with this approach. Furthermore, Quantitative Microbiological Risk Assessment models predict that the health benefits from water quality interventions drop significantly with even occasional consumption of contaminated water. Therefore, to be effective, HWT options need to achieve high user compliance rates and provide safe water reliably.
I begin my thesis with an interdisciplinary analysis of the field of water, health, and development, followed by a description of my research study site. Using an interdisciplinary research approach, grounded in the local context, I led the development of an ultraviolet (UV) water disinfection system for rural households. This included an iterative process of design and field tests to create a user-friendly system and laboratory research to improve the performance of the technology. I also collaborated with a non-profit organization based in Mexico in the design of an implementation program to support the adoption and consistent use of the UV system.
Then I present the design and application of a stepped-wedge cluster randomized trial in rural Mexico to evaluate compliance with the implementation program and field efficacy of the UV system. I developed a framework that disaggregates and measures the components of compliance from initial adoption of a safe water practice to exclusive consumption of safe water. I applied this framework to measure compliance across intervention and control groups and to test if additional program components that improve convenience to users can be a cost-effective approach to increase compliance. I present evidence that the implementation program significantly improved compliance with the habit of consuming safe water, when compared to the practice of purchasing water bottled in reusable 20 L containers in the control group. The additional program components proved to be a cost-effective strategy to increase compliance immediately post-intervention, but their impact degraded with time. By analyzing results across different compliance components, I find limitations of the current HWT approach. I present the rational for pilot testing strategies outside the current HWT paradigm, such as expanding a narrow focus on drinking water to making all domestic water safe to drink or switching from a product-based to a service delivery model.
As a second component of the randomized trial, I present a series of controlled comparisons to evaluate the field efficacy of the UV system using E. coli as a fecal contamination indicator in drinking water. I use an as-treated-analysis to isolate the impact of the system and contrast these results with an impact evaluation of the implementation program led by a research colleague. I also created a drinking water reliability framework to compare potential contamination impacts from different household water management practices and a logistic regression model to assess household risk factors for post-UV-treatment contamination. I show that treating water with the UV system and storing it in 20 L narrow-necked containers, allowed households to significantly improve their drinking water quality and gain access to a more reliable source of safe water.
In the final chapter I investigate the greenhouse gas (GHG) emissions associated with the use of HWT technologies in Mexico. I do that by carrying out a literature review of existing studies assessing energy use of water treatment technologies; using secondary data to perform a life cycle assessment (LCA) capturing the embedded CO2 equivalent emissions of individual HWT products; and developing model to calculate a metric of GHG emissions per volume of water used representative of the HWT sector in Mexico. Filtration, ozone, and UV disinfection technologies resulted in similar LCA emissions, while reverse osmosis had emissions five times higher than the average of the rest. I also find GHG emissions of HWT to be 30 times lower than water bottled in 20 L reusable containers. In a context in which mortgage institutions have created green credit mechanisms, this result is useful for expanding financing options for HWT products, which are often more cost-effective than bottled water, but require a higher capital investment. (Abstract shortened by UMI.)
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Crane, Justin P. Whittington Dale. "Determining whether household water and sanitation indicators can be used for ex-ante evaluations to identify the poor in developing countries." Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2006. http://dc.lib.unc.edu/u?/etd,534.
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Thesis (M.S.)--University of North Carolina at Chapel Hill, 2006.Title from electronic title page (viewed Oct. 10, 2007). "... in partial fulfillment of the requirements for the degree of Master of Science in the Department of Environmental Sciences and Engineering, School of Public Health." Discipline: Environmental Sciences and Engineering; Department/School: Public Health.
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Peabody, Duncan. "Field and Laboratory Comparison of the Hydraulic Performance of Two Ceramic Pot Water Filters." Scholar Commons, 2012. http://scholarcommons.usf.edu/etd/4199.
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Currently 884 million people worldwide are living without access to an improved source of drinking water (WHO/UNICEF, 2011). Piped-water on premises is the ultimate goal of World Health Organization (WHO) due to the ability to treat all of the water and distribute it safely in pressurized pipes. However, Household Water Treatment and Safe Storage (HWTS) is an option for improving the quality of drinking water where that infrastructure is not yet developed, especially where there is a risk of recontamination between point of collection and point of use (Clasen, 2006).
This study analyzed one such HWTS, the ceramic pot water filter. The study compared the hydraulic properties of the FilterPure (FP) and Potters for Peace (PFP) ceramic pot filters through a thirteen-month field study in the Dominican Republic and laboratory studies at the University of South Florida.
In the field study 55 filters were tested for first hour flow rate and hydraulic conductivity. Eight first hour flow rate tests were conducted in the field on one month intervals during months 7- 13. FP filters had an average first hour flow rate of 553 ml/hr and PFP Filters had a first hour flow rate of 395 ml/hr. No significant change in first hour flow rate was observed over time in FP filters. PFP experienced an average increase of 31 ml/hr per month during the seven-month testing period.
Falling head tests were conducted on four filters in the laboratory and the flow rate was modeled to determine hydraulic conductivity. Hydraulic conductivity values for FP filters ranged from k = 0.0495 - 0.0831 cm/hr and for PFP filters ranged from k = 0.0136 - 0.0389 cm/hr.
Eight out of 29 (26%) Potters for Peace filters in the field had first hour flow rates of less than 250 ml/hr by month nine of the study and had to be replaced and removed from the study. In total 24 of 55 (44%) filters (8 FP and 16 PFP) had to be removed from the study due to several reasons discussed in this thesis.
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Ngai, Tommy Ka Kit. "How small non-governmental organizations can improve their program implementation strategies to increase the adoption and sustained use of household water treatment systems in the developing world." Thesis, University of Cambridge, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.609902.
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DAMANHURI, IMAM-SLAMET TRI-PADMI. "Contribution a la mise au point de tests d'activite biologique pour les dechets soumis a biodegradation." Paris 7, 1987. http://www.theses.fr/1987PA077029.
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L'utilisation du substrat enzymatique, le ttc, dans le test d'activite deshydrogenasique, permet d'evaluer l'activite de la biomasse active dans des milieux varies telle une boue activee, un milieu liquide anaerobie tel des lisiers, ou un milieu heterogene comme des ordures menageres. Ce test permet de prevoir l'apparition d'un phenomene de gonflement des boues en presence de germes filamenteux. Il est utilisable egalement comme outil toxicologique, puisqu'il permet d'identifier le mode d'action du toxique sur le systeme enzymatique controle. Dans les milieux heterogenes naturels, comme dans une decharge d'ordures menageres, il permet d'avoir une indication sur le potentiel energetique d'un dechet ou sur l'age d'un dechet ou d'un produit organique en cours de stabilisation
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Bolton, Martin. "Design and development of an improved low-cost ceramic water filter based on the existing Potpaz home water treatment device for use within rural households of the Vhembe region." Thesis, 2012. http://hdl.handle.net/10210/4513.
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M.Tech.This project aimed to develop the Potpaz ceramic water filter into an improved filter design optimally suited to South African rural conditions, to provide potable water rather than contaminated water to households. Communities that do not have access to in-house treated water often end up with a contaminated water supply, as the water to be consumed is usually sourced from communal water collection points and stored in containers. There is evidence that the water consumed at point-of-use in rural areas is not always of a potable quality due to possible contamination between collection and consumption. The existing Potpaz home water treatment device has been scientifically proven to return contaminated water to a potable state. A limited number have been imported to South Africa for use in a project that studied the effect of household point-of-use treatment on the health of the consumer. It was not at all certain whether the households would use these devices effectively because this filter was not part of their everyday water system. Part of investigating whether or not they would effectively use this filter was the inclusion of industrial design within the filter assessment section of a larger research project conducted in the Vhembe region to understand the requirements of the user. Industrial design concerns itself with the requirements of the user, as well as knowledge regarding product design, development and manufacturing. Households that took part in the point-of-use project used the Potpaz home water treatment device for more than two months and were approached to provide feedback regarding its use. From the feedback, it became evident that there were aspects of the Potpaz design that needed modification towards an improved water filter more suited for its intended use in rural households. An Action Researchinfluenced methodology and User Centred Design approach informed the collection of original data and feedback on areas of improvement. This, together with visits to local shops and community potters, provided sufficient background to understand the needs and preferences of the intended rural users regarding the use of the device. This informed the design process and increased the chances of developing a readily accepted, more suitable product to the intended users and the domestic environment in which they live. To achieve this, this project focused on the following aspects regarding Potpaz filters: placement, use and design aspects of usability and ergonomics. Development of the improved filter design culminated in rapid prototyping of a scale model and the fabrication of a full-size working model allowing for physical interface to evaluate the success of the design solution.
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"Point of use water treatment options in rural Cambodia households: An analysis of the effectiveness of solar water disinfection in Rovieng District, Preah Vihear Province, Cambodia." Tulane University, 2006.
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Arouna, Aminou [Verfasser]. "Domestic and agricultural water use by rural households in the Oueme River Basin (Benin) : an economic analysis using recent econometric approaches / presented by Aminou Arouna." 2009. http://d-nb.info/998073024/34.
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Ketzenberger, Brent A. "Part I - Water use by kitchen food waste disposers in households Part II - Effect of ground food wastes on septic tank/soil absorption fields - critical review of literature /." 1995. http://catalog.hathitrust.org/api/volumes/oclc/33114729.html.
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Thesis (M.S.)--University of Wisconsin--Madison, 1995.Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 90-91).
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Msimango, Langalibalele Innocent. "A critical evaluation of urban water management: comparative case studies of Meadowlands Township, Soweto and Florida suburb, Roodepoort." Diss., 2018. http://hdl.handle.net/10500/25156.
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Water is a vital component for human survival but unsustainable patterns of water consumption are still evident internationally. In South Africa, water conservation has traditionally been limited to the responsibility of the state, with little effort being made by the consumers. However, as water scarcity increasingly becomes a problem, government and residents need to find out how urban South Africans can access water and implement water conservation methods in their homes without the support of government supervision programmes. This study explores the relationship between urban residences in two different parts of Johannesburg (Meadowlands in Soweto and Florida in Roodepoort) and their consumption, perception and usage of water and its conservation. Based on interviews with residents from different backgrounds, the results of this research show that residents have varied but generally limited concern for water issues. Findings from this study indicate that for a resident to conserve water, the type of abode in which he/she lives is irrelevant. Whether the resident lives in suburban home or small government funded housing, the attitudes of the interviewees and the perceptions which they expressed regarding solutions to the water dilemma proved to be similar: people in these urban areas are aware of the importance of water conservation, however, there is limited practice thereof.Geography
M. Sc. (Geography)
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Argo, Emily E. "Factors Influencing Household Outdoor Residential Water Use Decisions in Suburban Boston (USA)." 2016. https://scholarworks.umass.edu/masters_theses_2/405.
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Water withdrawals for human use can reduce water in lakes and streams, with significant consequences for aquatic biota. Urbanization, particularly large lawn areas associated with low-density residential development, increases demand on freshwater resources. Outdoor water use accounts for the largest proportion of residential water use during the summer months, which corresponds to the lowest water levels in freshwater ecosystems. Prior studies have sought to understand property features associated with the highest water use; however, these studies do not consider other types of water use nor do they capture the decisions by residents that result in outdoor water use. Understanding these decisions is critical for developing policies and education tools that reduce outdoor water use by changing people’s water use behavior. Focusing on the Ipswich River Watershed, which has been impacted by extreme low flows due to water withdrawals, a mixed-methods approach was used to understand residents’ outdoor water use and the factors influencing the amount and timing of water use. To quantify water use meters were placed on outdoor spigots at residences, participants were provided with a written survey before and after water metering, and in-person interviews were conducted. Irrigation systems used the most water; however, garden watering occurred as frequently as lawn irrigation and many participants indicated that their garden was a primary factor in water use decisions. Participants’ water use decisions fell into categories from habitual (i.e., watering at the same time of day) to purely cognitive (i.e., watering based on weather and plant needs). While many participants felt that water conservation was necessary, their willingness to implement landscape-level conservation practices, such as rain barrels, did not differ from participants who believed water conservation was unnecessary. Interestingly, many residents reduced their outdoor water use behavior and increased their concern for other environmental issues in response to study participation. To have the greatest impact on overall water use, efforts should focus on residents running irrigation systems on a schedule. Outreach should emphasize individualized approaches to water conservation, regardless of water source (public or private), and include information and conservation options specific to the water needs of the individual property.
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WANG, BO-YANG, and 王柏揚. "Study of Activated Carbon Water Treatment and UV Sterilization Equipment for Household Use." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/ejg8xn.
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碩士國立高雄應用科技大學
電機工程系博碩士班
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Holding a cup of handmade beverage or sugary drink in hand seems very common in Taiwan. A lot of children even drink beverage instead of water. However, drinking too much beverage with sugar、spices and artificial additives will cause obesity、diabetes、 metabolic disease and have negative impact to health. Considering to our health, we should cultivate the habit of drinking water since childhood. Drinking proper amount of water can improve blood circulation, transfer nutrient, and eliminate body toxicant. Moreover, it can increase metabolism, provide lubrication of joints、organs and tissues、and regulate the temperature of the body to maintain our health. The water purification plants in Taiwan have equipped with full water quality inspection system which can test more than twenty items of water quality. The results can conduct quality control and serve as the basis of quality assurance. However, because of the regional and seasonal factors in Taiwan, water source and quality change frequently. Traditional purification procedure may not provide clean household water. Therefore, many families boil water to sterilize their drinking water. Nonetheless, boiling cannot ensure safety of drinking water. Therefore, different types of water purification equipment come on the market. Selection of water purification facility becomes an important matter. In order to learn the water quality condition in different areas, the selection of the water purification facility in this research should pay attention to the average water quality of water purification plants in these areas. Besides, whether the water purification facility passes national certification or not also needs to be checked out. To ensure the water quality of water purification facility, the examination content also needs to be compared. This research adopts high-density activated carbon filter with ultraviolet lamp to filter water. Free available residual chlorine, total dissolved solids, and total number of clump are used to ensure that the filtering function of the water purification facility can control the water quality.
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CHIU, PIN-YU, and 邱品瑜. "Evaluation of Household Water Use Behavior on Greenhouse Gas Emissions from Water Supply System by System Dynamic：A Case Study of Taipei City." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/tsw9j7.
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碩士國立臺北大學
自然資源與環境管理研究所
106
Above 60% portable water in Taiwan are unusable and directly flow into the ocean due to geospatial and temporal distribution. Therefore, Taiwan is ranked the 20th country with water shortage. Households are the main user of the water supplied by water supply system according to the manual published by the Water Resources Agency in Taiwan (2007) and living habits and education would affect usage of water (SWMM, 2012). General public should improve their conscious about water usage. This study used questionnaires to closely understand living habits of water usage from households in Taipei City. Evaluating generated greenhouse gases from water usage and monetizing them into environmental costs leading to increasing water price. In addition, the System Dynamic (SD) model was used to connect the results of questionnaires and mathematical equations. The results of study would be helpful to promote water resources sustainability and treasure limited water resources. According using water saving measures can reduce water consumption by 5% to 20% (Sønderlund et al., 2014). Therefore, this study is used to set five scenarios to simulate household water consumption changes. The results of study showed that the water supply system consumed about 5.427-) of greenhouse gas. In order to encourage prople to cherish the use of water, this study use reasonable price formula to calculate new water price 9.85 NT dollar per unit. This water price includes the environmental cost 0.03 NT dollar per unit. Looking at the System Dynamic (SD) simulation results, the total water consumption with scenario1 is 1.520(m3) lower than the baseline year, with drop of 5%, scenario2 is 2.902(m3) lower than the baseline year, with drop of 9%, scenario3 is 4.164(m3) lower than the baseline year, with drop of 13%, scenario4 is 5.320(m3) lower than the baseline year, with drop of 17%, scenario5 is 6.272(m3) lower than the baseline year, with drop of 20%.
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Ramulongo, Luvhimba. "An evaluation of urban household water demand and consumption in Vhembe District: a case study of Makhado Local Municipality, Limpopo, South Africa." Diss., 2016. http://hdl.handle.net/11602/822.
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Hung, Stephanie. "Evaluating the Toxicity and Formation of Halobenzoquinones in Point-of-Use Chlorinated Drinking Water." 2018. https://scholarworks.umass.edu/masters_theses_2/734.
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Chlorine has effectively reduced the prevalence of waterborne diseases, however there are secondary consequences to this public health advancement. Disinfection byproducts (DBPs) are chemicals formed when chlorine reacts with natural organic matter (NOM) in water. A new class of DBPs, halobenzoquinones (HBQs), has recently been identified and data suggests it could be potentially carcinogenic and up to 1000 times more toxic than some regulated DBPs. So far, in vitro studies have assessed HBQ toxicity without taking into account its transformation in cell media into potentially less toxic compounds. This study evaluated the toxic effects of one HBQ, 2,6-DCBQ, and its transformed derivatives on colon epithelial and liver hepatoma cell lines by measuring intracellular reactive oxygen species production and cell viability post-DCBQ exposure. In addition, to better quantify the trade-off between exposure to waterborne pathogens and 2,6-DCBQ, the inactivation of a virus indicator (MS2), and formation of DCBQ were determined in chlorinated surface waters. Dose-dependent toxic effects were observed in both cell lines and transformed DCBQs were observed to be less toxic than their parent compound. MS2 inactivation occurred immediately post-chlorination, but DCBQ was detected simultaneously. Such findings indicate that this compound is toxic to human cells, including colon epithelial cells, which may be pertinent due to the possible association between chlorinated waters and colon cancer. Findings also suggest this DBP may be relevant in developing countries because HBQs may form in point-of-use chlorinated drinking waters. Furthermore, observed reduction in toxicity of media-transformed DCBQs calls current literature on HBQ toxicity into question.
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Singh, Urisha. "The health-related microbial quality of drinking water from ground tanks, standpipes and community tankers at source and point-of-use in eThekwini Municipality : implications of storage containers, household demographics, socio-economic issues, hygiene and sanitation practices on drinking water quality and health." Thesis, 2009. http://hdl.handle.net/10413/8362.
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The aim of this study was to investigate the microbiological quality of drinking water at the
source (taps at eThekwini laboratories, standpipes and mobile community tankers) and
corresponding point-of-use (storage containers and ground tanks) supplied to peri-urban areas
in Durban by eThekwini Municipality. It also aimed to identify factors associated with
deterioration in water quality such as storage of water, household demographics, hygiene and
sanitation practices. In order to determine the microbial quality of drinking water, the pour
plate method (for enumeration of heterotrophic organisms) and the membrane filtration
technique (for total coliforms and E. coli enumeration) were used. Conductivity, turbidity, pH
and total and residual chlorine levels of drinking water were measured. Microbial and
physico-chemical data was collated and statistically analysed with epidemiological data from
an associated study to determine the link between microbial quality of drinking water,
household demographics, health outcomes, socio-economic status, hygiene and sanitation
practices. Findings showed that all point-of-use water was unsafe for human consumption as
a result of either poor source water quality, in the case of standpipes, and microbial
contamination at the point-of-use, in the case of ground tanks and community tankers. The
latter could be attributed to unsanitary environments, poor hygiene practices or poor wateruse
behaviour. Households which included children aged 0-5 years and in which open-top
containers were used for water storage had the highest rates of diarrhoea and vomiting. Water
from ground tanks had the best microbial quality but people in households using this water
presented with the highest rate of diarrhoea. Therefore provision of microbially safe drinking
water will not reduce the rate of health outcomes if addressed in isolation. In order to reduce
water-associated illness, provision of safe and adequate amounts of water, hygiene and
sanitation education and education on water-use behaviour should be provided as a package.
The provision of improved water delivery systems does not ensure that drinking water is safe
for human consumption. Measures, such as point-of-use water treatment should be
considered to ensure that drinking water provided at the source and point-of-use is
microbially safe for human consumption.Thesis (M.Sc.)-University of KwaZulu-Natal, 2009.
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Ntema, Vusi McMillan. "Detection of Vibrio cholerae and Vibrio parahaemolyticus by molecular and culture methods from source water to household container-stored water at the point-of-use in rural Vhembe communities in South Africa." Thesis, 2010. http://hdl.handle.net/10210/3100.
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M.Tech.With the recent cholera outbreak in Zimbabwe and the outbreak taking a sub-regional dimension with cholera cases being reported from neighbouring countries like Botswana and South Africa, there was a need to monitor drinking water from environmental water sources as well as household water-storage containers at the point-of-use in rural communities. Although conventional culture-based microbiological methods for the identification of Vibrio species from environmental water samples are reliable, they require several days to complete (Khan and Cerniglia, 1994). Culture dependent and culture independent methods for the detection of Vibrio cholerae and Vibrio parahaemolyticus from water samples were optimised during the current study. With these methods, the occurrence and distribution of V. cholerae and V. parahaemolyticus in source waters as well as in household container stored-waters at the point-of-use in the Nwanedi Catchment, was determined. The culture based approach analyses involved the enrichment of water samples in alkaline peptone water (APW) for 18 hours at 37°C followed by culture on selective thiosulfate-citrate-bile salts-sucrose (TCBS) agar. Typical colonies on TCBS agar were confirmed using the API 20NE as well as the two multiplex polymerase chain reactions (m-PCR). The culture independent PCR approach was done by filtering 100 ml of the water sample onto polycarbonate membranes followed by DNA extraction from the bacteria captured on the membranes using an adaptation of the in-house DNA extraction method used in the laboratory. This DNA was used as template for the m-PCR’s. For the culture based PCR detection, 100 ml water was filtered onto nitrocellulose membranes followed by 18 hours enrichment in APW. DNA was then extracted from the enrichment broth and subsequently used as template for the m-PCR’s. All water samples were analysed with all three methods to compare the results and determine the most effective method for the detection of the two-selected Vibrio species present in water samples. PCR analyses were performed using two m-PCR assays targeting the SodB (V. cholerae species), FlaE (V. parahaemolyticus species) and 16S rRNA (Vibrio and Enterobacteriacea species) genes (Multiplex 1) and the V. cholerae O1 and V. cholerae O139 rfb genes, ctxA (cholera toxin) gene and 16S rRNA gene (Multiplex 2). The 16S rRNA primers were included in the Multiplex PCR’s as an internal control. The m-PCR assays were 100% specific for total and toxigenic V. cholerae and total V. parahaemolyticus when using target bacteria and various other non-target bacteria. The m-PCR assays when coupled with an 18 hours enrichment step could detect as few as 4-10 V. cholerae and V. parahaemolyticus cells in pure cultures as well as in spiked environmental water samples. Fifty water-storage containers and 56 environmental water samples (river, spring and borehole) from rural households in the Vhembe district of the Limpopo Province of South Africa were tested for the presence of selected Vibrio’s, using (1) the standard culture based approach, (2) PCR detection without enrichment and (3) PCR with a brief pre-enrichment. Container water samples were collected before [referred to as free volume (FV) of water] and after dislodging of the biofilm [referred to as dislodged biofilm (BD)] from the inner sidewalls of containers. Of the samples analysed with the standard cultured based technique combined with colony confirmation using m-PCR 1, 34 (12.8%) tested positive for the presence of V. cholerae (SodB gene), 2 (1.3%) for the presence of V. parahaemolyticus (FlaE gene) and all the samples tested positive for the 16S rRNA gene. In contrast, only 1 (0.6%) tested positive for the presence of V. cholerae and 0 (0%) for the presence of V. parahaemolyticus when the isolates were confirmed with API 20NE. With the culture dependant PCR method, 65 (41.7%) of the samples tested positive for the presence of V. cholerae, 3 (1.9%) for the presence of V. parahaemolyticus and all the samples tested positive for the 16S rRNA gene. Seventeen (10.9%) of the samples tested positive for the presence of V. cholerae (SodB) and 16S rRNA genes, 0 (0%) for the presence of V. parahaemolyticus (FlaE gene) with the culture independent direct PCR detection protocol. All the samples that tested positive for V. cholerae with any of the three methods were tested for the presence of toxigenic V. cholerae species with the second multiplex PCR. Six of the source water samples tested positive for V. cholerae O1 as well as the cholera toxin genes. Of the 56 source water samples, 14 (25%) were positive for V. cholerae and 0 (0%) were positive for V. parahaemolyticus with one or all of the methods. Six (10.7%) of the V. cholerae positive samples tested positive for V. cholerae O1 rfb gene, and ctxA gene (cholera toxin). Thirty (60%) of the 50 FV and 28 (56%) of the DB water samples tested positive for V. cholerae, and 3 (6%) of the FV and 0 (0%) of the DB samples tested positive for V. parahaemolyticus with one or all of the methods. None of the positive V. cholerae samples tested positive for the presence of toxigenic V. cholerae. The results presented suggest that the use of culture-based techniques alone is inadequate for detection of selected Vibrio’s in the environmental water samples and that such techniques are not enough to guarantee satisfactory protection of human health. The combination of filtration, enrichment, DNA extraction and m-PCR method provide a sensitive and specific method for the detection of V. cholerae and V. parahaemolyticus in environmental water samples. This method proved to be the most effective for detection and identification of selected Vibrio’s when compared to the culture based method and PCR without enrichment method. The inclusion of an enrichment period allows for the detection of culturable bacteria which is crucial as PCR detection does not give indications on the viability of the detected material. The enrichment period will also dilute any inhibitors for the m-PCR’s that may be present. Detection of V. cholerae and V. parahaemolyticus in the source water used by the population and in the water-storage containers indicates possible seeding of containers with Vibrio species from the source water. Furthermore, the detection of these organisms in DB samples indicates that these organisms attach to containers’ inner sidewalls, forming biofilms, further sustaining their occurrence and proliferation. The detection of V. cholerae and V. parahaemolyticus in household water-storage containers certainly places the consumers at risk of infection of diseases caused by these organisms.