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Arizona Wells: Low Yielding Domestic Water WellsUhlman, Kristine, Artiola, Janick 01 1900 (has links)
3 pp. / Arizona Well Owner's Guide to Water Supply / To develop a ground water resource, it is necessary to design and construct a well capable of yielding a pumping rate compatible with the needs of the water well owner. Sufficient and sustained well yields are highly dependent on the characteristics of the aquifer, the construction of the well, and the maintenance of the well. Causes of low-yielding wells are explained and practices to restore well performance are recommended.
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Hydrogeological Assessment for a Suitable Location of a Reservoir Lake in George County, MississippiLadner, Corey T (Cory Tanner) 17 August 2013 (has links)
The construction of a reservoir lake was proposed in 2010 for George County, Mississippi, USA. The proposed reservoir would be designed to serve primarily for industrial water storage. As the preliminary portion of the reservoir project, a baseline watershed assessment was performed for the purpose of identifying a reservoir site with potential to fill a lake volume capable of providing a sufficient water supply to prevent the Pascagoula River near Graham Ferry, Mississippi from dropping below a measured 7Q10 base flow when 100 million gallons of water per day are withdrawn from the river for industrial use. The initial focus of the assessment was on three watersheds Big Creek, Big and Little Cedar Creek, and Escatawpa River. Evaluations of surface water quantity and quality measurements along with reservoir daily water storage models suggested two reservoirs were suitable for continuation of the reservoir project.
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Using SLEUTH Land Cover Predictions to Estimate Changes in Runoff Quality and Quantity in the Delmarva PeninsulaCiavola, Suzanne J. 04 May 2011 (has links)
Anticipating future trends in land development and climate change is a constant challenge for engineers and planners who wish to effectively compensate for the resulting changes in stormwater runoff that will inevitably follow. This study is a regional attempt at predicting how predicted changes in land cover will affect runoff characteristics in a number of watersheds throughout the Delmarva Peninsula when compared to the current state. To predict changes in land cover and the associated land use, the SLEUTH model coupled with PED utilized a number of different inputs including population growth trends, existing geography, current land planning policies as well as different growth factors to predict where urban growth is most likely to occur. The model creates maps which show the approximate location of predicted growth for the year 2030.
Using SLEUTH output, the magnitude of changes that can occur in runoff quality and quantity due to land cover changes were estimated in each of the seventeen representative watersheds that were chosen within the Delmarva Peninsula. Changes in water quality were calculated based on nutrient loading rates for sediment, phosphorus, and nitrogen. These nutrient loading rates correspond to different land uses within different county segments in the peninsula. The expected changes in water quantity were quantified using the United States Department of Agriculture's Natural Resources Conservation Services' TR-20 which estimated the peak flows for each watershed based on watershed's size, land cover, soils, and slope.
Evaluating the magnitude of these potential changes in the Delmarva Peninsula provides an important look into the effects of increased urban development on the predominantly agrarian land mass, the majority of which drains to the Chesapeake Bay. / Master of Science
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Advancing cumulative effects assessment methodology for river systemsSeitz, Nicole Elyse 14 April 2011
Increased land use intensity has adversely affected aquatic ecosystems within Canada. Activities that occur over the landscape are individually minor but collectively significant when added to other past, present, and reasonably foreseeable future actions, and are defined as cumulative effects. Existing approaches to cumulative effects assessment for river systems within Canada are ineffective. This thesis aims to improve the practice of cumulative effects assessment by evaluating current methodology for linking landscape change and river response over a large spatiotemporal scale. As part of this goal, I offer a framework for better incorporating science into current practices for cumulative effects assessment. The framework addresses the challenges involved in cumulative effects assessment, such as defining appropriate spatial and temporal scale, complex ecological and hydrologic pathways, predictive analysis, and monitoring. I then test the framework over a large spatiotemporal scale using a case study of the lower reaches of the Athabasca River Basin, Alberta. Three objectives are addressed: 1) changes in land use and land cover in the lower ARB for several census dates (1981, 1986, 1991, 1996, 2001) between 1976 (historic) and 2006 (current day) are identified; 2) linkages between landscape change and river water quality and quantity response are evaluated; and 3) results of the different methods used to link landscape stressors with stream responses are compared. Results show that the landscape has changed dramatically between 1976 and 2006, documented by increases in forest harvesting, oil sands developments, and agricultural intensity. Secondly, results suggest that linear regression tests combined with regression trees are useful for capturing the strongest associations between landscape stressors and river response variables. For instance, water abstraction and agricultural activities have a significant impact on solute concentrations. This suggests that water abstraction and agriculture are important indicators to consider when conducting a watershed cumulative effect assessment on a similar spatiotemporal scale. The thesis has strong implications for the need for improved water quality and quantity monitoring of Canada‟s rivers. The research provides a means of identifying appropriate tools for improved watershed cumulative effects assessment for scientists and land managers involved in the environmental impact assessment process and protection of Canada‟s watersheds.
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Advancing cumulative effects assessment methodology for river systemsSeitz, Nicole Elyse 14 April 2011 (has links)
Increased land use intensity has adversely affected aquatic ecosystems within Canada. Activities that occur over the landscape are individually minor but collectively significant when added to other past, present, and reasonably foreseeable future actions, and are defined as cumulative effects. Existing approaches to cumulative effects assessment for river systems within Canada are ineffective. This thesis aims to improve the practice of cumulative effects assessment by evaluating current methodology for linking landscape change and river response over a large spatiotemporal scale. As part of this goal, I offer a framework for better incorporating science into current practices for cumulative effects assessment. The framework addresses the challenges involved in cumulative effects assessment, such as defining appropriate spatial and temporal scale, complex ecological and hydrologic pathways, predictive analysis, and monitoring. I then test the framework over a large spatiotemporal scale using a case study of the lower reaches of the Athabasca River Basin, Alberta. Three objectives are addressed: 1) changes in land use and land cover in the lower ARB for several census dates (1981, 1986, 1991, 1996, 2001) between 1976 (historic) and 2006 (current day) are identified; 2) linkages between landscape change and river water quality and quantity response are evaluated; and 3) results of the different methods used to link landscape stressors with stream responses are compared. Results show that the landscape has changed dramatically between 1976 and 2006, documented by increases in forest harvesting, oil sands developments, and agricultural intensity. Secondly, results suggest that linear regression tests combined with regression trees are useful for capturing the strongest associations between landscape stressors and river response variables. For instance, water abstraction and agricultural activities have a significant impact on solute concentrations. This suggests that water abstraction and agriculture are important indicators to consider when conducting a watershed cumulative effect assessment on a similar spatiotemporal scale. The thesis has strong implications for the need for improved water quality and quantity monitoring of Canada‟s rivers. The research provides a means of identifying appropriate tools for improved watershed cumulative effects assessment for scientists and land managers involved in the environmental impact assessment process and protection of Canada‟s watersheds.
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Confronting the Water Crisis of Beijing Municipality in a Systems Perspective : Focusing on Water Quantity and Quality ChangesMa, Jin January 2011 (has links)
In recent decades, water systems worldwide are under crisis due to excessive human interventions particularly in the arid and semi-arid regions. In many cities, the water quantity situation has become more and more serious, caused either by absolute water shortage or water pollution. Considering population growth and fast urbanization, ensuring adequate water supply with acceptable water quality is crucial to socio-economic development in the coming decades. In this context, one key point is to (re-)address various water problems in a more holistic way. This study explores the emerging water crisis events in Beijing Municipality so as to have a better understanding of water systems changes and to make more sustainable water-related decisions. The changes of water quantity and water quality in the region are analyzed in a systems perspective; and opportunities towards improved performance of Beijing’s water systems are discussed. In order to aid in water systems analysis, a conceptual framework is developed, with a focus on identifying the most important interactions of the urban water sector. The results of the study show that the emerging water crisis events in the Beijing region are caused by a variety of inter-related factors, both external and internal. The external factor is mainly the decreasing upstream surface water inflow into the Guanting and Miyun reservoirs. The internal factors include precipitation variation, excessive water withdrawals, increasing water demands for different purposes and a large amount of pollutants discharged to the receiving water bodies. These factors together have caused tremendous water systems changes in Beijing Municipality from both the water quantity and water quality perspectives. In order to alleviate the serious water situation in Beijing Municipality, many further efforts are required in the dynamic socioeconomic and ecological context. Although tremendous work has been carried out by water-related institutions to prevent flood and ensure water supply, water resources development, planning and management must be addressed employing systems thinking and in a more holistic way. This is crucial for balancing the tradeoffs of water quantity and water quality in the Beijing region. Besides the experimental inter-basin water transfer activities, water demand management and pollution reduction and prevention should be the top priority on the agenda of the Beijing government in the long term. Moreover, only at a river basin level may various upstream-downstream conflicts be alleviated by wiser water allocation among administrative regions, as well as taking the ecological water demand into consideration. Finally, considering the current water situation and water management system, the following three aspects of improvement are emphasized in the present study, including a promoted water centric value, institutional capacity building and employing economic principles for water resources management.
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Access to drinking water in low-and middle-income countries: monitoring and assessmentCassivi, Alexandra 02 September 2020 (has links)
Lack of access to drinking water remains widespread as 2.1 billion people live without safely managed service that includes improved water sources located on premises, available when needed, and free from contamination. Monitoring global access to drinking water is complex, yet essential, particularly in settings where households need to fetch water to meet their basic needs, as multiple factors that relate to accessibility, quantity and quality ought to be considered. The overall objective of this observational study is to increase knowledge surrounding monitoring and assessment of access to drinking water supply in low-and middle-income countries. The dissertation was comprised of five manuscripts which address the objective using various approaches including systematic review (manuscript 1), secondary data analysis (manuscript 2), and primary data analysis (manuscripts 3-5) to gather evidence towards improving access to drinking water. Primary data were collected through a seasonal cohort study conducted in Southern Malawi that included 375 households randomly selected in three different urban and rural sites. Methods used included structured questionnaires, observations, GPS-based measurements, and water quality testing. Findings from this study highlight the importance of conducting appropriate assessment of household behaviours in accessing drinking water in view of improving reliability of the indicators and methods used to monitor access to water. Seasonal variations that may affect water sources' reliability and household’s needs should be put forward to improve benefits of improving access to water and sustainable health outcomes. Further to target reliable and continuous availability from an improved water source at proximity to the household, interventions should aim to ensure safe quality of water at the point of use for mitigating the effect of post-collection contamination, and ensure sufficient quantities of water to allocate for personal and domestic hygiene. Focusing on the benefits of improving access to water at the point of consumption is essential to generate more realistic estimations, suitable interventions and appropriate responses to need. / Graduate
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Drinking Water Infrastructure Assessment with Teleconnection Signals, Satellite Data Fusion and MiningImen, Sanaz 01 January 2015 (has links)
Adjustment of the drinking water treatment process as a simultaneous response to climate variations and water quality impact has been a grand challenge in water resource management in recent years. This desired and preferred capability depends on timely and quantitative knowledge to monitor the quality and availability of water. This issue is of great importance for the largest reservoir in the United States, Lake Mead, which is located in the proximity of a big metropolitan region - Las Vegas, Nevada. The water quality in Lake Mead is impaired by forest fires, soil erosion, and land use changes in nearby watersheds and wastewater effluents from the Las Vegas Wash. In addition, more than a decade of drought has caused a sharp drop by about 100 feet in the elevation of Lake Mead. These hydrological processes in the drought event led to the increased concentration of total organic carbon (TOC) and total suspended solids (TSS) in the lake. TOC in surface water is known as a precursor of disinfection byproducts in drinking water, and high TSS concentration in source water is a threat leading to possible clogging in the water treatment process. Since Lake Mead is a principal source of drinking water for over 25 million people, high concentrations of TOC and TSS may have a potential health impact. Therefore, it is crucial to develop an early warning system which is able to support rapid forecasting of water quality and availability. In this study, the creation of the nowcasting water quality model with satellite remote sensing technologies lays down the foundation for monitoring TSS and TOC, on a near real-time basis. Yet the novelty of this study lies in the development of a forecasting model to predict TOC and TSS values with the aid of remote sensing technologies on a daily basis. The forecasting process is aided by an iterative scheme via updating the daily satellite imagery in concert with retrieving the long-term memory from the past states with the aid of nonlinear autoregressive neural network with external input on a rolling basis onward. To account for the potential impact of long-term hydrological droughts, teleconnection signals were included on a seasonal basis in the Upper Colorado River basin which provides 97% of the inflow into Lake Mead. Identification of teleconnection patterns at a local scale is challenging, largely due to the coexistence of non-stationary and non-linear signals embedded within the ocean-atmosphere system. Empirical mode decomposition as well as wavelet analysis are utilized to extract the intrinsic trend and the dominant oscillation of the sea surface temperature (SST) and precipitation time series. After finding possible associations between the dominant oscillation of seasonal precipitation and global SST through lagged correlation analysis, the statistically significant index regions in the oceans are extracted. With these characterized associations, individual contribution of these SST forcing regions that are linked to the related precipitation responses are further quantified through the use of the extreme learning machine. Results indicate that the non-leading SST regions also contribute saliently to the terrestrial precipitation variability compared to some of the known leading SST regions and confirm the capability of predicting the hydrological drought events one season ahead of time. With such an integrated advancement, an early warning system can be constructed to bridge the current gap in source water monitoring for water supply.
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Impacts of Land Cover and Climate Change on Water Resources in Suasco River WatershedTalib, Ammara 23 November 2015 (has links)
Hydrological balance and biogeochemical processes in watershed are significantly influenced by changes in land use land cover (LULC) and climate change. Those changes can influence interception, evapotranspiration (ET), infiltration, soil moisture, water balance and biogeochemical cycling of carbon, nitrogen and other elements at regional to global scales. The impacts of these hydrological disturbances are generally reflected in form of increasing runoff rate and volume, more intense and frequent floods, decreasing groundwater recharge and base flow, elevated levels of sediments and increase in concentration of nutrients in both streams and shallow groundwater. Water quality of Sudbury, Assabet and Concord (SuAsCo) watershed in Massachusetts is also compromised because of influx of runoff, sediments and nutrients. There is a crucial need to evaluate the synergistic effects of LULC change and climate change on the water quality and water quantity in a watershed system. A watershed simulation model is used to simulate hydrologic processes and water quality changes in sediment loads, total nitrogen (TN), and total phosphorus (TP). The model is calibrated and validated with field-measured data. Climatic scenarios are represented by downscaled regional projections from Global Climate Model (GCM) models and regional built out scenarios of LULC are used to assess the impacts of projected LULC and climate change on water quality and water quantity. Simultaneous changes in LULC and climate significantly affect the water resources in the SuAsCo River watershed. Change in climate increased ET (4.7 %) because of high temperature, but independent change in land cover reduced ET (6.5%) because of less available vegetation. Combined change in land cover and climate reduced ET (2.1%) overall, which indicates that land cover change has significant impact on ET. Change in climate increased total run off (6%) and this increase is more significant as compared to 2.7 % increase in total runoff caused by land cover change. Change in land cover increased surface runoff more significantly (69.2%) than 7.9 % increase caused by climate change. Combined change in land cover and climate further increased the average storm peak volume (12.8 percent) because of high precipitation and impervious area in future. There is a potential for reducing runoff, sediments and nutrients loads by using conservation policies and adaptation strategies. This research provides valuable information about the dynamics of watershed system, as well as the complex processes that impair water resources.
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Measuring and Understanding Effects of Prescribed Fire in a Headwater CatchmentErwin, Elizabeth G. 11 July 2019 (has links)
Headwater catchments play a large role in the storage and release of water and chemical constituents, thereby influencing downstream flows and water quality. Recent advances in water quality monitoring technologies have created an opportunity to better assess water chemistry variation by using high temporal resolution, in situ sensors. However, despite these new technologies, there have been limited studies on installation approaches and their effects on sensor measurements. Accurate in situ monitoring is particularly important to capture catchment disturbance effects that may be highly dynamic over time (e.g., following storms) or limited in duration. For example, prescribed fire is a commonly applied forest management tool, but there remain questions regarding how this disturbance affects catchment soils and resultant stream water chemistry. Effective assessment of prescribed fire thus requires coupled monitoring of both soil properties and water chemistry. In this thesis, I addressed two linked objectives: i) assess the effects of commonly used protective housings on in situ sensor measurements (Chapter 2) and ii) evaluate prescribed burn effects in a southwestern Virginia, USA headwater catchment (Chapter 3). In Chapter 2, I compared four different housing types (mesh, screen, holes, and open) using in situ specific conductance measurements over time and from salt tracer injections for discharge estimates. This study demonstrated substantial effects from some of the housing types evaluated, where flow resistance reduced water exchange between stream water and water in contact with the sensor. From these findings, I suggest that in situ water quality sensors should be deployed in housing types with large openings perpendicular to flow. In Chapter 3, I assessed prescribed fire effects on soil properties (particle size, aggregate stability, and chemistry), stream discharge, and fine-scale water chemistry dynamics. Findings demonstrated some significant differences following fire in soil properties (e.g., overall decrease in aggregate stability, general decreases in total carbon and nitrogen of mineral soils), water quality (e.g., increased levels of DOC, turbidity, and nitrate) and discharge (increases in stage and flow). While these changes were statistically significant, differences in parameters before and after fire were generally small. Future work should examine if these effects persist through time, and whether the minor level of disturbance observed in this study results in any negative environmental impacts. / Master of Science / Headwater catchments (where precipitation first becomes streamflow) provide important aquatic habitat and regulate downstream water flows and chemistry. Recent advances in water quality monitoring technologies have created an opportunity to better assess water chemistry variability by using high frequency, submerged water quality sensors. However, these new technologies present new, unique challenges, such as measurement errors that may be induced by different installation methodologies. Accurate measurements are particularly important to evaluate how changes in catchment conditions (e.g., soils, vegetation) impact local and downstream water quality. For example, prescribed fire is a commonly used forest management tool, but questions remain about how it affects catchment soils and headwater stream chemistry. Consequently, understanding the effects of this and other catchment disturbances requires coupled monitoring of both soil properties and water quality. In this thesis, I addressed two objectives: i) assess the effects of commonly used protective housings on water quality sensor measurements (Chapter 2) and ii) evaluate prescribed burn effects in a southwestern Virginia, USA headwater catchment (Chapter 3). In Chapter 2, I demonstrated substantial effects from some of the housings evaluated and suggest that water quality sensors should be deployed in housing types with large openings perpendicular to flow. In Chapter 3, I demonstrated some significant effects of prescribed fire on soil properties (e.g. overall decrease in soil stability, general decreases in total carbon and nitrogen of mineral soils), water quality (e.g., increased levels of dissolved organic matter, turbidity, and nitrate) and flow (increases in stream water levels and flow). While these changes were statistically significant, differences in parameters before and after fire were generally small. Future work should examine if these effects persist through time, and whether this minor level of disturbance causes any negative environmental impacts.
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