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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

On the Distributional Implications of Safe Drinking Water Standards

Cory, Dennis C., Taylor, Lester D. 28 March 2017 (has links)
The provision of safe drinking water provides a dramatic example of the inherent complexity involved in incorporating environmental justice (EJ) considerations into the implementation and enforcement of new environmental standards. To promote substantive EJ, implementation policy must be concerned with the net risk reduction of new and revised regulations. The regulatory concern is that higher water bills for low-income customers of small public water systems may result in less disposable income for other health-related goods and services. In the net, this trade-off may be welfare decreasing, not increasing. Advocates of Health–Health Analysis have argued that the reduction in health-related spending creates a problem for traditional benefit-cost analysis since the long-run health implications of this reduction are not considered. The results of this investigation tend to support this contention. An evaluation of the internal structure of consumption expenditures reveals that low-expenditure households can be expected to react to an increase in the relative price of housing-related goods and services due to a water-rate hike by reducing both housing and health-related expenditures. That is, the representative low-expenditure household re-establishes equilibrium by not only decreasing housing-related spending, but also by decreasing spending on health-related expenditures in a modest but significant way. These results reflect the fact that expenditures on housing are a major proportion of overall household spending, and that accommodating drinking water surcharges exacerbates both health and food security concerns for low-expenditures households.
2

Synthesis of silver nanoparticles and investigating their antimicrobial effects

Sithole, Zimasa N. January 2015 (has links)
>Magister Scientiae - MSc / Water is essential for life, yet access to safe drinking water is still a major concern worldwide due to waterborne diseases. The current study proposes silver nanoparticles (AgNPs) as an antibacterial agent. Silver nanoparticles were synthesised using different reductants and stabilisers, and the resulting structures were characterised with Ultra-violet visible (UV-vis) spectroscopy, transmission electron microscopy (TEM), energy-dispersive spectroscopy (EDS) analysis. The antibacterial properties of the AgNPs were tested against a panel of 5 indicator organisms: Cupriavidus metallidurans, Staphylococcus epidermidis, Mycobacterium smegmatis, Bacillus cereus and a multi-drug resistant Escherichia coli 1699. Spherical AgNPs that absorbed at around 400 nm, with diameters ranging between 18.8-26.4 nm or 5.4-13.1 nm were prepared by ascorbic acid or sodium borohydride respectively. The optimum processing conditions that produced 6±1.8 nm spherical nanoparticles included maintaining the temperature at 0 ⁰C, the pH at 9.78 and the NaBH4/Ag/PVP ratio at 16:1:10. Exposing AgNPs to light for 6 hours did not alter the particle size rather it changed the particles shape from spherical to icosahedral. Stirring caused particles to agglomerate, however, no agitation resulted in the formation of irregular structures of different sizes. Sensitivity to the AgNPs ranged between 25 % and 100 % reduced bacterial growth depending on the strains used and the concentration of the AgNPs. The Gram negative bacteria were more sensitive to AgNPs than Gram positive bacteria. However silver ions were more toxic than AgNPs for all but one of the strains tested, B. cereus was completely resistant to both Ag+ and AgNPs. C. metallidurans and E.coli (1699) showed a dose dependent sensitivity to AgNPs and the minimum inhibitory concentrations were established at 50 and 20 mg/L AgNPs respectively. C. metallidurans and E.coli (1699) were also eradicated by 10 mg/L Ag+. The E. coli TEM images showed accumulation of AgNPs within the cells, cell shrinking and leakage of cellular components. This suggests that AgNPs have a similar toxicity effect on bacterial cells as Ag+.
3

A Comparative Analysis of Wellhead Protection: Virginia and Massachusetts

Raftery, Kelley Lynne 12 June 2002 (has links)
Proactive drinking water programs assist communities in the long-term protection of their water supply. The 1986 amendments to the Safe Drinking Water Act (SDWA) seek to protect groundwater sources of public drinking water. 42 United States Code Section 300h-7 created the Wellhead Protection Program. The 1986 SDWA Amendments require all states to submit a Wellhead Protection Program for public groundwater drinking sources. The 1996 SDWA Amendments require all states to submit Source Water Assessment Plans for both groundwater and surface water sources. The 1986 and 1996 SDWA Amendments aim to protect public health by preventing contamination of drinking water sources. <p> This paper compares and contrasts the effectiveness of groundwater Wellhead Protection Programs (WHPP) in Virginia and Massachusetts. These states take different management approaches to protect public groundwater drinking sources. Virginia encourages local governments to participate voluntarily in wellhead protection activities. Massachusetts requires all municipal and private suppliers that provide public drinking water to adopt a WHPP. The relative success achieved by Massachusetts and Virginia was evaluated with two measures: percentage of wellhead protection programs implemented and the percentage of state reported drinking water quality violations. / Master of Urban and Regional Planning
4

High-Frequency Nitrate Monitoring in Dynamic River Systems: the Case of Three Iowa Rivers in the Mississippi Basin

Banerjee, Malini De 01 July 2013 (has links)
High frequency water quality monitoring presents unique and unlimited opportunities of exploring spatio-temporal variation in water quality. Knowledge gained from analyzing high frequency water quality data can provide more clarity regarding transportation and processing of water constituents over time and space and scale. This study analyzes high frequency discharge, nitrate load and concentration data for three watersheds of different sizes - Cedar River Watershed, North Raccoon and Middle Raccoon. Each of these sites were monitored for 2-3 calendar years. Sudden spikes in discharge, nitrate concentration and load data, also defined as "events" were analyzed in great detail to understand the patterns in event occurrence and event intensity. Smaller watersheds seemed to have sharper and "flashier" events compared to bigger watersheds. Nitrate concentration events were flatter in shape compared to discharge and nitrogen load events. The relationship between nitrogen concentration and discharge was found to be varying over time, unlike the relationship between nitrate load and discharge, which were almost perfectly correlated for most site-year combinations. Based on more than 40,000 simulations, it was determined that high frequency water quality sampling is not only efficient in capturing minute spatio-temporal variations but can also capture nitrate exceedances to a greater degree. High frequency sampling was also associated with higher yield ratio in nitrate load estimates, not only during high flow periods, but also during the non-high-flow period.
5

Environmental impacts of toxic substances: improving coastal resiliency in Florida

Korman, Aaron Manuel 01 October 2021 (has links)
Anthropogenic effects are causing significant environmental degradation, and regardless of actions taken to mitigate further changes, humans and animals will have to live with these impacts (IPCC 2019). Rapid population growth in coastal regions, saltwater intrusion (SWI), lowering water quality, and increased presence of toxic materials are degrading coastal resiliency. An important and popular coastal region for the United States is the state of Florida, and it is also an area extremely vulnerable to aspects of climate change such as sea-level rise (SLR) (Noss 2011). This project analyzes how the state is currently experiencing the direct and indirect impacts of toxic materials on the state’s people, environment, and economy. It will do so through analysis of the performance of federal legislation created with the intent to protect human and environmental health, quantification of current rates of using toxic chemicals and potential pollution, as well as quantifying effects of both anthropogenic and natural toxic materials on Florida’s housing market. It was anticipated that legislation such as the Safe Drinking Water Act (SDWA) to ensure strict enforcement of drinking water standards and the Emergency Planning Community Right to Know Act (EPCRA) to prevent toxic pollution would be present in the vulnerable region. Also that natural phenomenon such as the harmful algal blooms significantly degrade the housing market through decreasing income through tourism and lowering housing prices in coastal neighborhoods. This project found that the SDWA is not being enforced, EPCRA data shows a huge risk to potential exposures from large storms, and that algal blooms are significant to housing prices in the state. Using these scientific findings to improve policy and appropriately communicating complex scientific topics to the public is extremely important. Doing so will enable a higher level of coastal resiliency as communities continue attempt to mitigate climate change, but also learn to understand current impacts and better live in a degrading environment.
6

Estimation of Number of People Living in Developing Countries that Received Water from a Spring Source

Shinde, Prapti 17 March 2019 (has links)
In the year 2000, 170 countries decided to stand together and solve some primary and common global problems like poor health, water, and sanitation. Obtaining access to safe drinking water is every individual’s right. The UN defines safe drinking water as “the water required for each personal or domestic use must be safe, therefore free from micro-organisms, chemical substances and radiological hazards that constitute a threat to a person's health” (UNDESA, 2014). This thesis focuses on identifying the number of people who potentially receive spring water from a piped source in rural mountainous areas. There are three significant steps and data requirements which are necessary to meet this study’s objective. These are to: 1) obtain data classifying the various sources of drinking water in each country by specifying the percentage of population served by a particular water in rural and urban areas, 2) determine the number of countries which are undeveloped or developing, and 3) identify specific countries which are defined as mountainous (and thus likely to have spring fed piped water systems) based on elevation and slope in order to estimate the number of people living in mountainous areas. Results show that 183.54 (million) people were estimated to receive piped water from the springs in mountainous areas. Approximately, 34% of the population is from the Eastern Asia and South-Eastern Asia regions, and 33% reside in the Latin America and Caribbean Islands. These were followed by Western Asia and North Africa Regions with 15% and Central Asia and Southern Asia Regions with 14% of their population estimated to receive piped spring water.
7

AN INTERNSHIP IN WATER UTILITY STAKEHOLDER RELATIONS

Vieux, Micah Steven 09 May 2013 (has links)
No description available.
8

OUTREACH COORDINATOR FOR THE UNREGULATED CONTAMINANT MONITORING REGULATION: AN INTERNSHIP WITH THE UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

Wagner, Cory J. January 2003 (has links)
No description available.
9

Household access to water and willingness to pay in South Africa: evidence from the 2007 General Household Survey

Kimbung,Ngum Julious January 2011 (has links)
<p>This study assesses the present level of household water access and the willingness to pay in South Africa. Although the general literature informs that progress has been made in positing South Africa above the levels found in most African countries, there are some marked inequalities among the population groups and across the provinces, with some performing well and others poorly in this regard. The study looks at the extent to which households differ in terms of water access and willingness to pay according to the province of residence. The study focuses on household heads / male and female, through different social and demographic attributes, by taking account of variables such as age, education&nbsp / attainment, geographic areas, and population group to name but a few. The data used in this study comes from the 2007 General Household Survey (GHS) conducted by Statistics South Africa. The scope is national and employs cross tabulation and logistic regression to establish relationships and the likelihood of living in a household with access to safe&nbsp / drinking water in South Africa. Results presented in this study suggest that the difference is determined by socio- demographic characteristics of each household such as age, gender, population group, level of education, employment status income, dwelling unit, dwelling ownership, living quarters,household size and income. It throws more light as to what needs to be taken into account when considering demand and supply of and priorities for water intervention from the household perspective.</p>
10

Household access to water and willingness to pay in South Africa: evidence from the 2007 General Household Survey

Kimbung,Ngum Julious January 2011 (has links)
<p>This study assesses the present level of household water access and the willingness to pay in South Africa. Although the general literature informs that progress has been made in positing South Africa above the levels found in most African countries, there are some marked inequalities among the population groups and across the provinces, with some performing well and others poorly in this regard. The study looks at the extent to which households differ in terms of water access and willingness to pay according to the province of residence. The study focuses on household heads / male and female, through different social and demographic attributes, by taking account of variables such as age, education&nbsp / attainment, geographic areas, and population group to name but a few. The data used in this study comes from the 2007 General Household Survey (GHS) conducted by Statistics South Africa. The scope is national and employs cross tabulation and logistic regression to establish relationships and the likelihood of living in a household with access to safe&nbsp / drinking water in South Africa. Results presented in this study suggest that the difference is determined by socio- demographic characteristics of each household such as age, gender, population group, level of education, employment status income, dwelling unit, dwelling ownership, living quarters,household size and income. It throws more light as to what needs to be taken into account when considering demand and supply of and priorities for water intervention from the household perspective.</p>

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