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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.
121

Assessment of Atrazine in a Rural Water Source: Rough River Lake, Kentucky

Sharp, Scotty 01 December 2006 (has links)
Atrazine [2-chloro- 4-(ethylamino)-6-(isopropylamino)-l,3,5-triazine], a widely used herbicide in US corn production, impacts quality of drinking water for many rural water supply systems. Four systems at Rough River Lake, Kentucky, have had high levels of atrazine in raw water and in some cases finished water that have exceeded the legal limit of 3 parts per billion (ppb). The Rough River Lake watershed is 1,700-km2, much of which is located in limestone karst. A hypothesis was developed stating that there would be higher concentrations of atrazine in the northeast section of the Rough River Watershed, located in Hardin County, due to the no-till corn production of the area and karst features. Surface and subsurface samples were collected from eighteen locations (including all major tributaries) within the study area. Sampling began during the Spring of 2005 growing season on a fourteen-day cycle and a twenty-eight day cycle during the fall and winter months. Atrazine concentrations rose at nearly all sites within weeks of the spring application in May, and then began to decrease by late July. Five locations had over 3 ppb for at least two sampling rounds. Two sites exceeded 10 ppb. Global Polynomial Interpolation Analysis was used as both a data exploration tool and a way to demonstrate a definite spatial and temporal pattern to atrazine within the study area. It was also concluded, the reservoir with its larger volume and lower water velocity plays a significant affect on a longer residence time of atrazine, while the tributaries showed lower concentrations of atrazine most likely due to higher velocity and smaller volume of water.
122

Take Me to the River: Revitalizing LA's Lost Monument

Childs, Erin 01 May 2012 (has links)
The tale of South Korea's Cheonggyecheon River is one to warm an urban environmentalist's heart. Cheonggyecheon runs through the center of Seoul, a bustling metropolis of ten million that has been the capital of Korea since the 14th century. The Japanese were the first to sacrice Cheonggyecheon on the altar of urbanization, turning the River into a sewage system during their 35 year occupation between 1910 and 1945. Already thusvdegraded, it was easy for later administrations to eventually completely cover the river with the Cheonggye Road and Cheonggye Elevated Highway between 1958 and 1976. Cheonggyecheon became an exemplar of the expendability of urban environments in the face of modernization and economic growth, particularly the need for transportation in a quickly developing city. In the early 1990s it was discovered that extensive repair would be necessary to maintain the Highway, and with heavy political leadership of Mayoral Candidate Myung-Bak Lee, now the president of South Korea, the decision was made to restore the river rather than repair the road (Park, 2006).
123

Reducing Lead and Selenium from Drinking Water Using Limestone-based Material

Tumati, Sindhu 01 May 2012 (has links)
Contamination of drinking water with metals is a major problem facing many areas of United States and the World. There is a need for an inexpensive remediation technology for the removal of metals in drinking water that can be applied to small rural water systems. This research will focus on the development of a process for removal of select metals from drinking water by limestone-based material. Metals in drinking water considered for this research include lead and selenium. Limestone-based material has demonstrated the potential to reduce select metals (lead, cadmium and arsenic) in drinking water, with the additional benefit of low-cost disposal of a stable waste product in ordinary landfills. Earlier research by the principal investigators using limestone-based material for drinking water treatment has clearly shown that this material can achieve metals removal of greater than 90 percent. This project will investigate techniques to improve removal efficiency of limestone-based material through adsorption and precipitation. This research will assist in the development of a granular adsorbent product that will remove metals and that can be manufactured and sold for use at the drinking water source, at point-of-use, or at point-of entry.
124

Markets for Water Quantity and Quality: Addressing Water Scarcity and Pollution in Southern Alberta

2013 September 1900 (has links)
Where water resources are scarce and water quality is diminishing, market–based instruments have better potential than government regulation alone to increase the efficiency of resource use, to reallocate water to other uses and to improve water quality in an efficient and equitable manner. The SSRB is a region in Southern Alberta known for water scarcity, growing competition for water and, an increasing threat of pollution by point and non-point sources. This research has addressed the perceptions of stakeholders about proposed system of water quality trading to supplement the existing system of government regulation and water trading. A survey was structured to examine stakeholders’ perceptions about (1) resource status; (2) their rights and responsibilities under current system of administration, and (3) their rights and responsibilities under the proposed system. Survey results revealed stakeholders concerns about the ability of both existing and proposed systems to secure their access to water if annual water supply continues to decrease. Despite concerns about increasing scarcity respondents did not perceive transferability of water licences as important due to lack of trading experience and existence of regulatory barriers that impede markets and discourage participation. Reluctance to explore markets could have been as well related to the high risk of losing the unused water. Under the proposed system stakeholders’ perceptions of their abilities to secure rights pertaining to water quality improved. However, obtained data were insufficient to judge with certainty the applicability of the proposed system in the region. Results were inconclusive to determine the extent and origin of non-point source pollution by agriculture. Also, research is needed to determine how elimination of potential institutional barriers, i.e. a risk to lose water and inability to maintain private licences to instream flow, would influence stakeholders’ perceptions about their rights and responsibilities under proposed system.
125

Maui's freshwater : status, allocation, and management for sustainability

Grubert, Emily 21 December 2010 (has links)
The water system on Maui Island in Hawaii is an integral part of the island’s infrastructure, affecting energy, agriculture, waste, and domestic systems. Both the built and the natural water systems are likely to be altered over the coming decades. Maui’s two major industries are agriculture and tourism, which compete for water and land resources. Maui faces high costs for food and fuel it must import, and agricultural efforts might shift from plantation-scale monocropping to energy production or diversified agriculture for food. Simultaneously, land use changes (like deforestation), climate change, and cyclical droughts affect Maui’s freshwater supply. Water planning and management based on careful assessment can be valuable tools for a community expecting that water will become increasingly scarce. Since water plays a large role in many other systems, choices about water allocation and use can help the island move toward solutions of multiple problems at once, including energy scarcity, coastal protection, and financial health. This work provides a dynamic snapshot of Maui’s current built and natural water systems, then analyzes two potential water management actions: pumped storage hydroelectric facilities built on existing reservoirs and use of secondary treated wastewater to irrigate biomass for power. Based on cost estimates and alternative solutions, neither of these applications are currently judged viable. / text
126

Defining Efficient Water Resource Management in the Weber Drainage Basin, Utah

Wilde, Keith D. 01 January 1976 (has links)
The Weber Basin Water Conservancy District is a state institution, but its primary function is collecting money for the U.S. Bureau of reclamation, to pay for the Weber Basin Project. Different classes of water users pay markedly different fees for identical Project services. More than half of the water developed by the Project is not used consumptively, yet supply facilities continue to be built in the Basin because they are less expensive to their owners than prices charged for the underused capacity of the Project. Paradoxically, some Basin residents are bitterly resentful to both the District and the Bureau, claiming that water rights formerly their own have, by means of the Project, been stolen. That is, both the enemies and the proponents of the Project adhere to the Western orthodoxy that water is scarce and drought imminent. The principal difficulty of this investigation lay in identifying the nature of the problem, for the situation seemed full of contradictions. Consequently, the primary contribution of the dissertation is an explanation of Basin circumstances that accounts for arresting observations without inconsistency or contradiction. The most important hypotheses are, therefore, empirical, or historical and institutional. Economics, according to Richard T. Ely and Frank H. Knight, is a set of principles concerning what ought to be, not empirical descriptions of what is. Consistent with that perspective, once the nature of the problem is clear, applications of economic principles is a prescriptive judgement of how the problem may be resolved. The most important empirical hypotheses are as follows: Water is not scarce in the Weber Basin; neither are storage and conveyance facilities. All are abundant, even redundant. Nevertheless in combination with certain institutional arrangements and sustained propaganda campaign, this very abundance contributes to persistence of the attitude that water is scarce. Redundant facilities thereby encourage even more unneeded development. What appears on first examination to be a case of misallocated water resources by discriminatory prices, turns out to be a problem of distributing the burden of paying for excessive, unwanted public works. Water itself is a free good in the Basin. Actual distribution of the repayment burden is partly ideological and partly pragmatic; partly a political choice and partly a bureaucratic decision; partly a manifestation of agrarian policy and partly what the traffic will bear. If water is free, it is not an economic good, and not a subject for economic analysis. The Basin has an ample water supply, but water may nevertheless be locally and periodically scarce. The water problem is therefore one of conveyance and timing. Control of timing requires storage. Conveyance requires energy, as well as aqueducts. In the Weber Basin, conveyance energy may be either the controlled flow of falling (mountain) water, or electrically powered pumps tapping abundant groundwater reservoirs. The water development problem is therefore, an issue of alternative capital facilities for the control and delivery of water (itself abundant). Efficient resource allocation in water development is consequently relevant at the investment level; it is not a matter of pricing water. In this case, the major investment decisions have already been implemented, and the problem is one of evaluating distribution of the repayment burden. The relevant economics literature is principles of equitable taxation, and of public utilities' pricing. Application to the basin situation produces a conclusion that present arrangements are as equitable as could be devised. Further redundant investment (inefficient use of resources), however, could be avoided if the State Engineer's Office took a harder line on requests to drill new wells. The information provided in this work could be the basis for making such a program popularly acceptable.
127

Water Resource Management : Social Behaviour, Cultural Norms and Societal Structures

Sjögren, Olivia January 2015 (has links)
Water shortage is one of the greatest challenges that the world faces today. International and national water initiatives are increasing simultaneously with the number of implemented drinking-water projects. The provision of sustainable safe drinking-water supply is here conceptualized through the Sustainable Livelihood Approach with the view of helping poor people secure their essential basic needs, improve their quality of health and increase their livelihood opportunities. However, a lot of drinking-water projects do not end up with satisfactory outcomes. Widespread results have demonstrated low quality water resource management, worsened access to water supply, constructions shutting down and not the least, that consumers have not been able to take advantage of their new basic drinking-water systems. Projects have often failed in remote rural areas in developing countries where strong social norms, cultural values and power structures prevail. The research is based on identifying and analyzing to what extent past drinking-water projects have addressed public participation and been aware of social, cultural and structural surrounding factors. By using Gunilla Åkesson’s sociological framework the research also addresses the role and value of sociological aspects in drinking-water projects. It is found that past projects have often failed to include public participation and lacked situational awareness to a sufficient extent. The research show the importance for projects staff, managers and technicians to take into account social behaviors, cultural norms and societal structures in the local environment and to provide local people with health awareness and education. By taking this into consideration it would enable people to change their behavior and take advantage of the improved drinking-water systems provided for them. In conclusion, there is a need to address more sociological aspects in water resource management in order to promote sustainable safe drinking-water supplies in remote rural areas in developing countries. It can be argued that this is not only applicable in drinking-water projects but also in other areas of fields within grass root development work.
128

Using the Rangeland Hydrology and Erosion Model to assess rangeland management practices on the Kaler Ranch

Ross, Morgan 26 July 2013 (has links)
<p> It is difficult to assess rangeland management practices at a hillslope scale because of the spatial and temporal variability of ecohydrological processes across a landscape. The Conservation Effects Assessment Project (CEAP) aims to provide a cost-effective method for quantifying benefits of conservation practices on rangelands. This study uses the Rangeland Hydrology and Erosion Model (RHEM) to develop a framework to assess rangeland management practices by quantifying sediment yield and runoff. Kaler Ranch, located in Eastern Arizona, was used as a study site because of their recently implemented rangeland conservation practices. Vegetation parameters were developed based on field data collected across the ranch and used to represent various rangeland management scenarios in RHEM. Peak flow and sediment yield rates were determined for each scenario using RHEM and were used as metrics to evaluate rangeland condition. RHEM provided an adequate method to evaluate the relative differences between upland rangeland management scenarios; however, it was less effective at evaluating changes in management practices within a riparian area.</p>
129

Integrative Control of Curly Leaf Pondweed Propagules Employing Benthic Bottom Barriers| Physical, Chemical and Thermal Approaches

Barr, Thomas Calhoun, III 21 November 2013 (has links)
<p> The effective management of submersed aquatic macrophytes depends on understanding their reproductive biology. <i>Potamogeton crispus </i> L. (curlyleaf pondweed, Potamogetonaceae) produces numerous asexual propagules that make traditional management difficult. It has spread to roughly half of the counties in California (USA) from alpine habitats such as Lake Tahoe to the tidally influenced Sacramento-San Joaquin Delta. Studies were conducted from May 2012 till October 2012 at the bench and mesocosm scales in Davis and Sacramento, California, to explore the effects of benthic barrier control measures on the propagules (turions) of <i>Potamogeton crispus. </i> The first study examined the effects of three benthic barrier materials (jute, polyethylene and rubber) on turion sprouting. Jute benthic barrier material allows some light and oxygen through the fabric, while polyethylene allows oxygen, but not light. Rubber barrier material blocks light and oxygen exchange. Turion viability, as determined by sprouting, was then assessed post-treatment. Results showed no significant differences at the bench-scale for the untreated control (100% sprouting, SE=0%), jute (100% sprouting, SE=0%), or polyethylene treatments (96.9%, SE=2.1%) (n=16 for all treatments, &alpha; = 0.05). Rubber treatments resulted in 48.4% sprouting (SE= 10.6%; n=16). Results for the mesocosm experiments showed significant differences between the control and the jute and polyethylene treatments (control = 98.4% sprouting, SE= 1.6%; jute = 71.9% sprouting, SE= 4.5%; polyethylene= 70.3% sprouting, SE= 4.7%, n=16 for all treatments). Jute and polyethylene treatments were not significantly different in the mesocosm experiment. The mesocosm experiment with the rubber barrier significantly reduced sprouting (29.7% sprouting, SE= 6.1%; n=16) compared to other treatments. While light had minimal impact on sprouting, anoxia appeared to be the main factor inhibiting sprouting using benthic bottom barriers. Barrier induced anoxic stress combined with herbicides may potentially offer enhanced efficacy. The second study explored enhancement of the impermeable rubber barrier material with dilute acetic acid loaded into cassava starch "pearls". Turions were exposed for two weeks and then assessed for viability via post-treatment sprouting protocol with and without hydrosoil at the bench- and mesocosm-scale. Results for the bench-scale showed that the 20.8 mmol L<sup>&ndash;1</sup> acetic acid treatment was not significantly different (p=.4231) compared to the untreated control (Tukey HDS; p&le;0.05). However, the 41.6 mmol L<sup>&ndash;1</sup> acetic acid treatment was highly significantly different from the control (p-value &lt; 0.0001) at the bench-scale, but did not completely inhibit sprouting (mean sprouting of 31.25% (<i>SE</i>= 11.97)). Complete inhibition of sprouting turions occurred for both experiments at and above acetic acid concentrations of 83.3 mmol L<sup>&ndash;1</sup> (SE= 0). Results showed that tapioca starch saturated with acetic acid and combined with impermeable benthic barriers may offer an effective chemical treatment for the control of <i>Potamogeton crispus.</i> The final study examined hot water exposures under the barriers to kill and inhibit sprouting in turions. Heated water circulated under an insulated benthic bottom barrier may potentially offer a simple non-chemical rapid method to target surface propagules on the sediment, subterranean propagules and young plants. Heated water was used to treat <i>P. crispus</i> turions at the bench and mesocosm scales (25&deg;C, 40&deg;C, 50&deg;C, 60&deg;, 70&deg;C and 80&deg;C exposures for 30 to 300 seconds). Heated water exposures inhibited sprouting turions at 50&deg;C and 60&deg;C at the mesocosm and the bench scales, however, did not completely inhibit sprouting for all time exposures except at the bench-scale 60&deg;C treatment for 300 seconds. For 70&deg;C and 80&deg;C treatment exposures, there was a slight difference at the 30 second exposure mark, but at 60 second and beyond, all 70&deg;C and 80&deg;C treatments provided 100% inhibition. The cost to raise the temperature 60&deg;C from ambient water temperature under the contained limited volume under insulated barriers is estimated to be approximately $2 per 9.3 m<sup>2</sup> (100 ft<sup>2</sup>) for 5 minute treatments or $3459 ha<sup>-1</sup> ($1400 acre<sup>-1</sup>).</p>
130

Examining the effect of government structure and size on the performance of Mississippi community water systems

Barrett, Jason Roy 12 May 2015 (has links)
<p> Mississippi has an abundant supply of underground aquifers which are utilized by community water systems as their source of drinking water. As the demand for water increases through the increasing population and the influx of industries, there is a need to manage the consumption and distribution of this valuable resource. Since its inception, the Mississippi drinking water industry has spawned new regulations, new management options, and creative ideas to promote a safer more efficient community water system. </p><p> The Mississippi State Department of Health-Bureau of Public Water Supply's Capacity Development Assessment is a comprehensive survey completed annually for every community water system in Mississippi. The Capacity Development Assessment will be used to gauge the quality of performance of the specified community water systems based exclusively on size classification, exclusively on government structure classification, and government structure by size classification. </p><p> Over the past 15 years, Mississippi has seen several centralization efforts occur, where a municipality, utility district, and/or a rural water association merges with one or multiple adjoining or close proximity community water systems. This results in one of the three main legal structures of government over community water systems increasing in size in an effort to heighten performance. This research has analyzed the size (population) and government structures of Mississippi community water systems and has determined that economies of scale do exist. Government structure alone does not have an effect on the performance of community water systems but size alone does have an effect on the performance of community water systems. Municipalities and rural water associations reach optimal performance at the medium size classification and utility districts reach optimal performance at the small size classification. </p><p> Regardless of the driving force, it is valuable to see that all of the Mississippi consolidating government structures are able to achieve optimal performance. Future state and/or federal legislatures, county governments, city governments, public water supply associations, and business economic drivers can benefit by knowing which structure(s) of community water system governance is the most productive and efficient when the time comes to explore the option of persuasion or mandates to increase viability or heighten performance. </p>

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