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Statistical Analysis and Mechanistic Modeling of Water Quality: Hillsborough Bay, FloridaHackett, Keith 01 January 2011 (has links)
Nutrient pollution has been identified as a significant threat to U.S. coastal and estuarine water quality. Though coastal and estuarine waters need nutrients to maintain a healthy, productive ecosystem, excess nutrients can lead to eutrophication. There are significant potential negative consequences associated with eutrophication, including loss of habitat, loss of economic activity, and direct threats to human health. Hillsborough Bay experienced eutrophication in the 1960s and 1970s due to a rapidly growing population and associated increases in nutrient pollution. These eutrophic conditions led to more frequent phytoplankton and macroalgae blooms and declines in seagrasses. To address these problems, a series of actions were taken including legislation limiting nutrient concentrations from domestic wastewater treatment plants, development of water quality and nutrient loading targets, and establishment of seagrass restoration and protection goals. Since the 1970s, water quality improvements and increasing seagrass acreages have been documented throughout Tampa Bay. In the current study, a series of analyses and tools are developed to obtain a more in depth understanding of water quality in Hillsborough Bay. The first tool is a linked hydrodynamic and water quality model (Environmental Fluid Dynamics Code) of Hillsborough Bay which can be employed to predict water quality responses to proposed management actions. In the second part of the study, a series of water quality indices were evaluated. The most appropriate index for determining overall water quality in Hillsborough Bay was identified. Chlorophyll a is one of the constituents in the water quality index and is currently used to evaluate annual water quality conditions in Hillsborough Bay. Therefore, the statistical distribution that describes chlorophyll a concentrations in Hillsborough Bay was identified and robust confidence intervals were developed to better understand the uncertainty associated with chlorophyll a measurements. Previous work linked chlorophyll a concentrations in Hillsborough Bay to explanatory variables based on monthly estimates. These relationships were used to develop water quality targets for the system. In this study, the previously developed relationship was revisited, resulting in an improved statistical model that is more robust. This improved model can also be used to evaluate the previously proposed targets and to better predict future changes due to climate change, sea level rise, and management actions. Lastly, a new method was developed to estimate atmospheric temperature in the contiguous United States.
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Examining the Economic Costs and Sources of Potable and Nonpotable Water in Northern MexicoMarlor, Kathryn Marie 01 January 2012 (has links)
Water availability and the cost of different water sources have been studied at great length. However, information is still needed to determine the policy directions to be undertaken by nations that have not yet achieved universal coverage of an improved water source. To further examine differences in water availability and pricing in the context of the developing world, three communities in Northern Mexico were surveyed to determine the differences in water distribution schemes and associated costs between rural and urban centers. It was observed that rural communities without a piped water supply paid 13 percent more for potable water supplies and 39 percent more for nonpotable water supplies than urban communities with a piped water source. A relationship between access to piped water and the probability of contracting diarrhea was also observed, with households with access to piped water having a lower probability of contracting diarrhea than those households without, and experiencing a lower number of days per month with diarrhea, on average. This leads to the observation that rural communities, who typically are less likely to be able to afford a piped distribution system, are paying more for their water supplies than nearby urban centers, both in terms of the money spent each month for water resources, and the costs associated with contracting and treating diarrhea. Steps should be taken by Mexico and other developing nations to ensure that water is distributed equally and priced fairly, so that the more impoverished subsets of their populations are not paying higher prices for their water.
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Sustainable Livelihood Analysis of an Irrigation Project in Ta Haen, Cambodia.Rehberger Bescos, Irene 01 January 2012 (has links)
This study examines potential livelihood outcomes from a recently established irrigation project in Ta Haen, Cambodia, in a sustainable livelihoods framework. The aim of this SAUCE irrigation project is to provide water for drinking and irrigation purposes with the goal of enhancing food by producing an extra rice harvest, the staple, per year. Field research conducted in December 2011 provided qualitative data from questionnaires, key informant interviews, and participant and direct observation, in addition to quantitative data from water quality analysis focusing on arsenic (a potential risk), pH, EC and temperature. Most of the people in the village did not obtain an extra rice harvest in this first year of the project. However, they did plant other crops along the Ta Haen riverbanks. Average arsenic concentration was 32 ppb, above WHO guideline value (10 ppb). However, dose response data is uncertain at levels below 50 ppb, which makes river water use acceptable given that this is a major water source for the community. Preliminary results suggest that project sustainability and positive livelihood outcomes depend upon improving overall agricultural and water management practices by addressing quality issues, rationing water, and removing invasive water hyacinths that affect water quantity.
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Assessment of a Modified Double Agar Layer Method to Detect Bacteriophage for Assessing the Potential of Wastewater Reuse in Rural BoliviaHadley, Sakira N. 01 January 2013 (has links)
Water scarcity is a global concern that impacts many developing countries, forcing people to depend on unclean water sources for domestic, agricultural, and industrial needs. Wastewater is an alternative water source that contains nutrients needed for crop growth. Wastewater reuse for agriculture can cause public health problems because of human exposure to pathogens. Pathogen monitoring is essential to evaluate the compliance of wastewater with established World Health Organization (WHO) and U.S. Environmental Protection Agency (EPA) wastewater reuse guidelines. Indicator organisms are commonly used to detect pathogens in water and wastewater because they are quick and easy to measure, non-pathogenic, and have simple and inexpensive methods of detection.
The objective of this research was to develop a modified double agar layer assay method that can be conducted in the field to quantify bacteriophage to assess the quality of wastewater for agricultural reuse. Results from the modified double agar layer assay were used to investigate the potential of somatic coliphage as an indicator organism for assessing the potential presence of enteric viruses in developing world treated wastewater, and to use the criteria of a good indicator organism to compare the potential of two commonly used indicator organisms, somatic coliphage and fecal coliforms, as an indicator of enteric viruses in wastewater.
A modified EPA double agar layer method was developed and deployed in a developing world rural community to effectively quantify the concentration of somatic coliphage in a community managed wastewater treatment system composed of a Upflow Anaerobic Sludge Blanket (UASB) reactor followed by two maturation lagoons. The modified method served as a good indicator of enteric viruses in the water. Somatic coliphages were easily detected and quantified in the field setting using a modified double agar layer method. Somatic coliphage was found to be a potential indicator for enteric viruses rather than fecal coliforms because of their similarity in characteristics and resistances to wastewater treatment. The concentration of somatic coliphage was only reduced by 1.05 log units across the two series maturation lagoon system. Previous literature suggested removal would range from 2.1 to 4.6 log units. Influent wastewater (previously treated by an UASB reactor) had a concentration of 4.38 E+06 PFU/ 100 mL (standard deviation = ±3.7E+06, n = 9) and the treated effluent contained 3.90 E+05 PFU/100 mL (standard deviation = ± 4.5E+05, n = 8) of somatic coliphages. Results suggest that somatic coliphage is a good potential indicator for enteric viruses in wastewater but further research needs to be done.
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Turning Water into Wine: The Political Economy of the Environment in Southern California's Wine CountrySimms, Jason 01 January 2013 (has links)
This dissertation examines questions of water sustainability in contexts of wine production and state-led neoliberal development in the Temecula Valley, southern California, where wine tourism is at present being harnessed as an engine of economic growth. Natural and anthropogenic forces, such as global climate change, desertification, urban development, and the marketization and commodification of natural resources, affect the distribution and availability of water throughout the globe. As a result, the use of water, and associated political and environmental processes and consequences, in the production of global commodities, including wheat, citrus, and coffee, recently have come under increased scrutiny. Given wine's importance as a global commodity, and the concurrent growth of wine tourism as a worldwide phenomenon, local and regional water systems experience increasing strain to meet heightened demand for wine and the associated influx of tourists.
This dissertation presents an ethnographic account of water use in the production of wine in Temecula, a desert-like setting already deficient in water that faces increasing human-induced pressures on its limited supply. Despite its social importance, very few dedicated ethnographies of wine and winemaking within the United States exist.
This dissertation also describes the waterworld of Temecula, using (and critiquing) the model presented by Ben Orlove and Steven C. Caton that examines water in terms of value, equity, governance, politics, and knowledge systems, showing how these elements manifest in three "sites": the watershed, the water regime, and the waterscape. In Temecula, the winery serves as a central locus within the waterworld, a contested representation of the interests, goals, and perspectives of primary actors and stakeholders, while also serving as an important vector of landscape transformation through time. Despite this, no anthropological treatment examining water and winemaking within broader frameworks of the political economy of the environment and historical ecology is extant, a lacuna that this dissertation addresses.
Throughout 2012, I conducted ethnographic fieldwork including archival research, interviews, and participant-observation. For the majority of my fieldwork, I spent time at an established winery in Temecula, during which I participated in many tasks related to wine production, with a focus on water use. Throughout this process, I interviewed dozens of people, including long-time residents, early pioneers in the Temecula wine industry, winery and vineyard employees, water management professionals at local and state levels, environmental service technicians, and many others.
This dissertation demonstrates that under conditions of neoliberal development in challenging economic times in Temecula, environmental concerns such as water availability and sustainability are suppressed or downplayed in order to prioritize goals related to economic growth and development. Ultimately I suggest that developers and local business leaders are guiding this political legerdemain, even if only implicitly, above the din of objections from at least a good number of area wineries, vineyards, and residents. Also, I suggest that as an applied outcome, the totality of potential costs and outcomes at all scales, including regional, must be considered, rather than obfuscated, simplified, or restricted to a local boundary, especially in terms of natural resources and their governance, when such areas lie within locales inexorably connected within a delicate ecological web.
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Flexible Urban Water Distribution SystemsTsegaye, Seneshaw Amare 01 January 2013 (has links)
With increasing global change pressures such as urbanization and climate change, cities of the future will experience difficulties in efficiently managing scarcer and less reliable water resources. However, projections of future global change pressures are plagued with uncertainties. This increases the difficulty in developing urban water systems that are adaptable to future uncertainty.
A major component of an urban water system is the distribution system, which constitutes approximately 80-85% of the total cost of the water supply system (Swamee and Sharma, 2008). Traditionally, water distribution systems (WDS) are designed using deterministic assumptions of main model input variables such as water availability and water demand. However, these deterministic assumptions are no longer valid due to the inherent uncertainties associated with them. Hence, a new design approach is required, one that recognizes these inherent uncertainties and develops more adaptable and flexible systems capable of using their active capacity to act or respond to future alterations in a timely, performance-efficient, and cost-effective manner.
This study develops a framework for the design of flexible WDS that are adaptable to new, different, or changing requirements. The framework consists of two main parts.
The first part consists of several components that are important in the pre and post--processing of the least-cost design methodology of a flexible WDS. These components include: the description of uncertainties affecting WDS design, identification of potential flexibility options for WDS, generation of flexibility through optimization, and a method for assessing of flexibility. For assessment a suite of performance metrics is developed that reflect the degree of flexibility of a distribution system. These metrics focus on the capability of the WDS to respond and react to future changes. The uncertainties description focuses on the spatial and temporal variation of future demand.
The second part consists of two optimization models for the design of centralized and decentralized WDS respectively. The first model generates flexible, staged development plans for the incremental growth of a centralized WDS. The second model supports the development of clustered/decentralized WDS. It is argued that these clustered systems promote flexibility as they provide internal degrees of freedom, allowing many different combinations of distribution systems to be considered. For both models a unique genetic algorithm based flexibility optimization (GAFO) model was developed that maximizes the flexibility of a WDS at the least cost.
The efficacy of the developed framework and tools are demonstrated through two case study applications on real networks in Uganda. The first application looks at the design of a centralized WDS in Mbale, a small town in Eastern Uganda. Results from this application indicate that the flexibility framework is able to generate a more flexible design of the centralized system that is 4% - 50% less expensive than a conventionally designed system when compared against several future scenarios. In addition, this application highlights that the flexible design has a lower regret under different scenarios when compared to the conventionally designed system (a difference of 11.2m3/US$). The second application analyzes the design of a decentralized network in the town of Aura, a small town in Northern Uganda. A comparison of a decentralized system to a centralized system is performed, and the results indicate that the decentralized system is 24% - 34% less expensive and that these cost savings are associated with the ability of the decentralized system to be staged in a way that traces the urban growth trajectory more closely. The decentralized clustered WDS also has a lower regret (a difference of 17.7m3/US$) associated with the potential future conditions in comparison with the conventionally centralized system and hence is more flexible.
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Improving Summer Drought Prediction in the Apalachicola-Chattahoochee- Flint River Basin with Empirical DownscalingDean, John Robert 16 July 2008 (has links)
The Georgia General Assembly, like many states, has enacted pre-defined, comprehensive, drought-mitigation apparatus, but they need rainfall outlooks. Global circulation models (GCMs) provide rainfall outlooks, but they are too spatially course for jurisdictional impact assessment. To wed these efforts, spatially averaged, time-smoothed, daily precipitation observations from the National Weather Service cooperative network are fitted to eight points of 700 mbar atmospheric data from the NCEP/NCAR Reanalysis Project for climate downscaling and drought prediction in the Apalachicola-Chattahoochee-Flint (ACF) river basin. The domain is regionalized with a factor analysis to create specialized models. All models complied well with mathematical assumptions, though the residuals were somewhat skewed and flattened. All models had an R-squared > 0.2. The models revealed map points to the south to be especially influential. A leave-one-out cross-validation showed the models to be unbiased with a percent error of < 20%. Atmospheric parameters are estimated for 2008–2011 with GCMs and empirical extrapolations. The transfer function was invoked on both these data sets for drought predictions. All models and data indicate drought especially for 2010 and especially in the south.
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Evaluating the Effectiveness of Regulatory Stormwater Monitoring Protocols on Groundwater Quality in Urbanized Karst RegionsNedvidek, Daniel C. 01 August 2014 (has links)
Non-point pollution from stormwater runoff is one of the greatest threats to water quality in the United States today, particularly in urban karst settings. In these settings, the use of karst features and injection wells for stormwater management results in virtually untreated water being directed into the karst aquifer. Currently, no policies exist specifically to provide water quality protections to karst environments. This study utilized a combination of karst stormwater quality data, along with survey data collected from MS4 Phase II communities, and an analysis of current federal, local, and state water quality regulations, to assess the need for karst-specific water quality regulations. Water quality data indicate that significant levels of contamination are mobilized during storm events, and often are directed into the karst system via Class V injection wells. Survey data collected from MS4 stakeholders in the karst regions of Kentucky indicate stakeholders are generally unable to explain local karst regulations or the steps taken to develop them. This confusion comes in part from insufficient progress on evaluation criteria available for the MS4 Minimum Control Measures (MCMs). Karst waters are often placed into the legal “gray zone” due in part to differences in definitions of key terms in state and federal regulations. This study recommends the development of regulations specific to karst waters at the state and federal levels through either the adaptation of existing or creation of new policies, which place an emphasis on the integration of water quality monitoring and karst education.
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Ground Water Flow and Water Resources Investigation of the Auburn, Summers and Shakertown Springs Karst Ground Water Basins, Logan and Simpson Counties, KentuckyHowcroft, William 01 December 1992 (has links)
The City of Auburn is faced with a number of problems relating to its dependency on two karst springs, Auburn and Summers Springs, to meet its water requirements. Besides being extremely vulnerable to contamination, the springs often discharge and insufficient volume of water needed for public consumption and dilution of the City’s treated wastewater. Thus the City wishes to find an additional source of water and views nearby Shakertown Spring as a possibility. The study has three main objectives: 1) delineation of the Auburn, Summers, and Shakertown Springs ground water basins, 2) determination of the volume of available water at each spring, and 3) investigation of additional potential water supplies as alternatives to the use of Shakertown Spring. A well survey and karst hydrogeological inventory, supplemented by dye tracing, were conducted to reveal water table information necessary for ground water basin delineation and construction of a potentiometric map. Water monitoring stations were constructed at the three springs, discharge measurements performed and stage monitored over a fifteen month period. The Auburn, Summers, and SHakertown Springs Karst Ground Water Basins are estimated to possess areas of 9.74, 3.49 and 19.02 square miles (25.23, 9.04, and 49.26 square kilometers) respectively. Summers Spring was found to have an estimated base flow discharge of 1 – 2 cubic feet per second (cfs) (0.03 – 0.06 cubic meters per second (cms)) and Shakertown Spring an estimated base flow discharge of 8 – 9 cfs (0.2-0.3 cms). Estimation of base flow discharge at Auburn Spring was not possible due to the location of the City’s water intake pipe at the spring head. However, a minimum discharge of .22 cfs (0.01 cms) was recorded on thirteen separate occasions during the period monitored. Five alternatives for the City of Auburn, including Shakertown Spring and two additional, though smaller, water sources are presented. The best source of water for the City must be decided with consideration of cost and need. A potentiometric map depicting ground water basins, water table contours and subsurface flow routes is presented as a tool for the City of Auburn to aid in decisions regarding its water resources.
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Addressing Water Resource Issues In Barbados Through An Isotopic and Atmospheric Characterization of Precipitation VariabilityHall, Veronica 01 May 2014 (has links)
Numerous studies have analyzed isotopic variation of meteoric and dripwater in karst environments for paleoclimate reconstructions or aquifer recharge capacity. What is poorly understood is how the isotopic signal of δ18O and δ2H is transferred through the hydrologic cycle based upon storm type, frequency, intensity, and teleconnection activity in the tropical karst areas. At Harrison’s Cave, Barbados, a Hobo Onset event data logger was attached to a tipping bucket rain gauge to count the tips and record the total rainfall every 10 minutes. In the cave a Hobo data logger was used to record relative humidity and temperature at 10-minute intervals. Rainwater, dripwater, and stream water samples were collected at a weekly resolution and refrigerated before sample analysis. The study period was from July, 2012 to October, 2013, with data from the data loggers only until June, 2013 due to inability to reach the study site. The samples were analyzed using the Picarro Cavity Ring Down Spectroscopy Unit-Water L1102-I through laboratories at the University of Kentucky and the University of Utah. The samples were reported in per mil and calibrated. The teleconnection (NAO, AMO, and ENSO) and other atmospheric data were obtained from the Climate Prediction Center or the NOAA Earth System Research Laboratory-Physical Sciences Division. The weekly isotope signatures were linearly regressed against total rainfall for Harrison’s Cave and surface temperature with no statistically significant correlation, indicating the amount effect was not present at a weekly resolution. The amountweighted precipitation δ18O values were calculated on a monthly basis and compared to TRMM monthly rainfall and island-wide monthly rainfall, and a statistically significant negative correlation was found between both datasets. This confirmed that the amount effect dominates the island’s rainfall isotopic signature at a monthly resolution, and that specific atmospheric influences represented in weekly rainfall were less influential on a weekly basis. It is hypothesized that the variation in weekly rainfall is due to quick initiating, rain-out, and dissipation of convective storm systems over the island. In terms of evaporative influences, the samples do not deviate much from the Global Meteoric Water Line (GMWL), indicating minimal evaporation, which is typical for tropical locations. When the d-excess parameters were calculated, there were distinct variations with minimal evaporation occurring in the 2013 calendar year. This is attributed to coastal storm formation in the tropics.
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