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1
Eden, Susanna. "Deciding to Recharge." Diss., The University of Arizona, 1999. http://hdl.handle.net/10150/191242.
Full textAbstract:
Public water policy decision making tends to be too complex and dynamic to be described fully by traditional, rational models. Information intended to improve decisions often is rendered ineffective by a failure to understand the process. An alternative, holistic description of how such decisions actually are made is presented here and illustrated with a case study. The role of information in the process is highlighted. Development of a Regional Recharge Plan for Tucson, Arizona is analyzed as the case study. The description of how decisions are made is based on an image of public water policy decision making as 1) a structured, nested network of individuals and groups with connections to their environment through their senses, mediated by their knowledge; and 2) a nonlinear process in which decisions feed back to affect the preferences and intentions of the people involved, the structure of their interactions, and the environment in which they operate. The analytical components of this image are 1) the decision makers, 2) the relevant features of their environment, 3) the structure of their interactions, and 4) the products or outputs of their deliberations. Policy decisions analyzed by these components, in contrast to the traditional analysis, disclose a new set of relationships and suggest a new view of the uses of information. In context of information use, perhaps the most important output of the decision process is a shared interpretation of the policy issue. This interpretation sets the boundaries of the issue and the nature of issue-relevant information. Participants are unlikely to attend to information incompatible with the shared interpretation. Information is effective when used to shape the issue interpretation, fill specific gaps identified as issue-relevant during the process, rationalize choices, and reshape the issue interpretation as the issue environment evolves.
2
Eden, Susanna, and Donald R. Davis. "Deciding to Recharge." Department of Hydrology and Water Resources, University of Arizona (Tucson, AZ), 1999. http://hdl.handle.net/10150/615798.
Full textAbstract:
Public water policy decision making tends to be too complex and dynamic to be
described fully by traditional, rational models. Information intended to improve
decisions often is rendered ineffective by a failure to understand the process. An
alternative, holistic description of how such decisions actually are made is presented here
and illustrated with a case study. The role of information in the process is highlighted.
Development of a Regional Recharge Plan for Tucson, Arizona is analyzed as the case
study.
The description of how decisions are made is based on an image of public water
policy decision making as 1) a structured, nested network of individuals and groups with
connections to their environment through their senses, mediated by their knowledge; and
2) a nonlinear process in which decisions feed back to affect the preferences and
intentions of the people involved, the structure of their interactions, and the environment
in which they operate. The analytical components of this image are 1) the decision
makers, 2) the relevant features of their environment, 3) the structure of their interactions,
and 4) the products or outputs of their deliberations. Policy decisions analyzed by these
components, in contrast to the traditional analysis, disclose a new set of relationships and
suggest a new view of the uses of information.
In context of information use, perhaps the most important output of the decision
process is a shared interpretation of the policy issue. This interpretation sets the
boundaries of the issue and the nature of issue-relevant information. Participants are
unlikely to attend to information incompatible with the shared interpretation. Information
is effective when used to shape the issue interpretation, fill specific gaps identified as
issue-relevant during the process, rationalize choices, and reshape the issue interpretation
as the issue environment evolves.
3
Stinson, Christian David. "Changes in Water Quality During Recharge of Central Arizona Project Water." Thesis, The University of Arizona, 1999. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_etd_hy0011_m_sip1_w.pdf&type=application/pdf.
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4
Brown, Steven Robin 1961. "Unconfined aquifer recharge from water table configuration modeling." Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/191899.
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The potential of estimating steady recharge to deep unconfined aquifers by comparing observed water levels to the water levels produced by a series of simulated cases was examined. Finite-element simulations were performed on an idealized region to examine the sensitivity of the water table position to anisotropy, recharge, grid density, horizontal layering, and region geometry. The position of the water table was found to be particularly sensitive to region geometry, medium heterogeneity and anisotropy. A graphical method based on comparison of water levels at three observation points to simulated water levels produced a good estimate of dimensionless recharge and the anisotropy ratio. Determination of the absolute value of recharge requires accurate determination of region geometry and hydraulic conductivity so that computer simulations are representative. An analytical solution to the Boussinesq equation was found to give a poor estimate of water table position and hence recharge for this case.
5
DeCook, K. J., and L. G. Wilson. "Ground-Water Recharge from Urban Runoff and Irrigation Returns." Water Resources Research Center. The University of Arizona, 2014. http://hdl.handle.net/10150/314278.
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No date on item.Preliminary information on urban runoff from selected small watersheds in the Tucson area indicates that average annual runoff from the urbanized areas is more than four times as much as that of a comparable undeveloped desert area, and may be ten times as much in some individual years. The urban runoff contains relatively high concentrations of bacterial loading and dissolved organics; although it is not now known to be a seriously hazardous source of pollutants in ground water, urban runoff should be monitored with increasing urban growth, especially for content of organics, microorganisms, and trace metals. Additional study also should be given to the travel-time regime of runoff from the small tributary urban watershed to the major stream channels where recharge mainly occurs. Deep percolation from irrigation return flows was evaluated during a one -year study for the U.S. Geological Survey's "Southwest Alluvial Basin, Regional Aquifer System Assessment Program". Objectives of the study included (1) identifying sources of recharge information, (2) collecting and summarizing available recharge information, (3) identifying methods for interbasin transference of recharge values, (4) characterizing deep percolation models, and (5) itemizing methods for overcoming data gaps. Apparently there is a difference in opinion among irrigation experts on the extent to which recharge from deep percolation occurs. One reason for the difference of opinion is that field measurements of the flux and velocity components of deep percolation through the vadose zone are scarce, particularly for deep alluvial basins. Similarly, there is a need for a simple, theoretically-based model of deep percolation /recharge. Many of the data deficiencies could be overcome by conducting lumped and site-specific field studies. Such studies, although expensive, would be timely in light of the current interest in ground-water management.
6
Fiaschetti, Aaron A. "Assessment of ground water exchange in two stream channels and associated riparian zones, Jocko Valley, western Montana." CONNECT TO THIS TITLE ONLINE, 2006. http://etd.lib.umt.edu/theses/available/etd-03012007-100218/.
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7
Alali, Emad Hussain. "Implementing a treated wastewater recharge technique and reverse osmosis unit system for water sustainability." Access citation, abstract and download form; downloadable file 37.69 Mb, 2004. http://wwwlib.umi.com/dissertations/fullcit/3131649.
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8
Virdi, Makhan. "Time Scale of Groundwater Recharge: A Generalized Modeling Technique." Scholar Commons, 2013. http://scholarcommons.usf.edu/etd/4786.
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Estimating the quantity of water that reaches the water table following an infiltration event is vital for modeling and management of water resources. Estimating the time scale of groundwater recharge after a rainfall event is difficult because of the dependence on nonlinear soil characteristics and variability in antecedent conditions. Modeling the flow of water through the variably saturated zone is computationally intensive since it requires simulation of Richards' equation, a nonlinear partial differential equation without a closed-form analytical solution, with parametric relationships that are difficult to approximate. Hence, regional scale coupled (surface water - groundwater) hydrological models make simplistic assumptions about the quantity and timing of recharge following infiltration. For simplicity, such models assume the quantity of recharge to be a fraction of the total rainfall and the time to recharge the saturated groundwater is scaled proportionally to the depth to water table, in lieu of simulating computationally intensive flow in the variably saturated zone. In integrated or coupled (surface water - groundwater) regional scale hydrological models, better representation of the timing and quantity of groundwater recharge is required and important for water resources management. This dissertation presents a practical groundwater recharge estimation method and relationships that predict the timing and volume accumulation of groundwater recharge to moderate to deep water table settings.
This study combines theoretical, empirical, and simulation techniques to develop a relatively simple model to estimate the propagation of the soil moisture wetting front through variably saturated soil. This model estimates the time scale and progression of recharge following infiltration for a specified depth to water table, saturated hydraulic conductivity and equilibrium moisture condition. High-resolution soil moisture data from a set of experiments conducted in a laboratory soil column were used to calibrate the HYDRUS-1D model. The calibrated model was used to analyze the time scale of recharge by varying soil hydraulic properties and simulating the application of rainfall pulses of varying volume and intensities. Modeling results were used to develop an equation that relates the non-dimensional travel time of the wetting front to excess moisture moisture content above equilibrium. This research indicates that for a soil with a known retention curve, the wetting front arrival time at a given depth can be described by a power law, where the power is a function of the saturated hydraulic conductivity. This equation relates the non-dimensional travel time of the wetting front to excess moisture content above the equilibrium moisture content. Since the equilibrium moisture content is dependent on the water retention curve, the powers in the equation governing the timing of recharge depend on the saturated hydraulic conductivity for a large variation in water retention curve. Also, the power law relates recharge (normalized by applied pulse volume) to time (normalized by the time of arrival of wetting front at that depth). The resulting equations predicted the model simulated normalized (relative) recharge with root mean square errors of less than 14 percent for the tested cases.
9
Abe, Joseph M. "Economic analysis of artificial recharge and recovery of water in Butler Valley, Arizona." Thesis, The University of Arizona, 1986. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_e9791_1986_2_sip1_w.pdf&type=application/pdf.
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Sjöholm, Pia. "Groundwater Recharge in Jakkur Lake : Possibilities and Risks of Sewage Water Reuse." Thesis, Uppsala universitet, Luft-, vatten och landskapslära, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-208989.
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The aim of this project is to study the nitrate levels of the treated water flowing into Jakkur Lake in Bangalore, from the treatment plant situated at the inlet to the lake, and thereby evaluate the function of the lake as for secondary and tertiary wastewater treatment as well as an infiltration basin. Obtained nitrate levels are used as indicators to study the wastewater flow in the lake, and to find other possible inflows of sewage which can affect the lakes’ total treatment efficiency. A literature study is done on wetlands and on groundwater recharge through infiltration basins, and the possibility of recharging groundwater below Jakkur Lake is evaluated. Water samples are collected around and in the lake and the samples are tested for nitrate, pH and total dissolved solids. Extra focus is put on research on nitrates in water.The risks of groundwater recharge in Jakkur Lake include pollution of wells by bacteria, viruses, parasites and traces of medicine. Further geotechnical investigations need to be pursued mainly on the soil structure under and around the lake, and studies need to be performed on the retention time of the water in the lake. The technical limitations such as fluctuations in efficiency and pollutant migration must be minimized, which initially could be done by building a constructed wetland and controlling the inflow to the lake.
11
Herndon, Roy Lee. "Hydrogeology of Butler Valley, Arizona an artificial recharge and ground-water storage prefeasibility study /." Thesis, The University of Arizona, 1985. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_e9791_1985_316_sip1_w.pdf&type=application/pdf.
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Gregory, Lucas Frank. "Water budgets and cave recharge on juniper rangelands in the Edwards Plateau." Texas A&M University, 2005. http://hdl.handle.net/1969.1/3791.
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Increasing demand for water supplies in semi-arid regions, such as San Antonio,
has sparked an interest in potential recharge management through brush control. Two
shallow caves under woody plant cover in northern Bexar County, Texas were chosen as
study sites where a detailed water budget would be developed. The Headquarters Cave
site measures natural rainfall and cave recharge while the Bunny Hole site is
instrumented to measure throughfall, stemflow, surface runoff, and cave recharge. Large
scale rainfall simulation was used at Bunny Hole to apply water directly above the cave
footprint allowing us to determine how recharge differs between natural and simulated
rainfall events. Under natural conditions, Headquarters Cave recharged 15.05% of the
annual rainfall while Bunny Hole received 4.28%. Natural canopy throughfall measured
59.96% of the water budget; stemflow accounted for 0.48% and canopy interception was
39.56%; no surface runoff was measured. Rainfall simulations conducted at Bunny Hole
resulted in an average of 74.5% throughfall, 5.3% stemflow, 20.2% canopy interception,
2.8% surface runoff, and 6.9% cave recharge; simulation intensities were typically
higher than natural event intensities. General water budgets across the Edwards Plateau have concluded that evapotranspiration represents 65% of total annual rainfall while
percolation and storage accounts for 30% and the remaining 5% is runoff. These studies
have been focused on broad water budget parameters while this study looks at more
detailed components. No other study to date has been able to combine throughfall,
stemflow, surface runoff, and vertical recharge monitoring to quantify the water budget
in the Edwards Plateau; these parameters are instrumental in determining a detailed
water budget in juniper rangelands. Results from this study illustrate the significance of
all aspects of the water budget and are the first to yield a firm measurement of actual
upland recharge.
13
Saunders, Robert J. "Artificial Recharge of Groundwater as a Water Management Option for Eastern Maine." Fogler Library, University of Maine, 2001. http://www.library.umaine.edu/theses/pdf/SaundersRJ2001.pdf.
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Correa, Ibargüengoitia José Antonio. "Institutional innovation in water management : the case of Mexico City's recharge wells." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/59734.
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Thesis (M.C.P.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 2010.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 108-125).
This thesis explores the difference in adoption patterns of water recharge well technology in Mexico City both by local entities and the central city government. The research finds that this technology, originally designed by the central city with the stated purpose of aiding aquifer recharge, was adopted by local entities driven by concerns over flood control. Geophysical realities, complemented by political and socioeconomic factors, are key in deciding the use and type of infiltration technology by local entities. Water policy priorities at the local level are a decidedly local affair, which makes coordination difficult and thus constitutes a challenge for sustainable water management in Mexico City as a whole. Ineffective formal coordination mechanisms among the three levels of government, and the incentives that explain the uneven adoption of recharge wells by local communities, suggest an alternative approach to metropolitan water governance. In addition to traditional solutions such as regulation and formal metropolitan cooperation bodies, a third path of sustainable water management would involve a division of tasks between high and lower local level governments. Levels of government with the resources and incentives to develop technologies with systemic impacts and that address immediate needs can then "market" or "scale down" these solutions to localities whose incentive structure would lead them to, in effect, implement these solutions. In this way, collective action problems could be sidelined at the metropolitan scale.
by José Antonio Correa Ibargüengoitia.
M.C.P.
15
Dickinson, Jesse Ervin, and Jesse Ervin Dickinson. "Inferring time-varying recharge from inverse analysis of long-term water levels." Thesis, The University of Arizona, 2003. http://hdl.handle.net/10150/626918.
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Water levels in alluvial aquifers of the Southwest typically vary in response to time
varying rates of mountain-front recharge. This suggests the possibility of inferring time
varying recharge rates on the basis of long-term water-level records. Presumably, these
recharge rates depend on variations in precipitation rates due to known climate cycles
such as the El Nino/Southern Oscillation index and the Pacific Decadal Oscillation. This
investigation examined the inverse application of a one-dimensional analytical model for
periodic flow [Townley, 1995] to estimate periodic recharge variations on the basis of
water-level variations in long-tenn water-level records. Time-varying water level records
at various locations along a flow path were obtained by simulation of ground-water flow
in numerical models of idealized basins. Time-varying recharge was represented as
sinusoidal recharge of a single period or as a composite of multiple periods of length
similar to known climate cycles. Periodic water level components, reconstructed using
singular spectrum analysis (SSA), were used to calibrate the analytical model to estimate
each recharge component. The results demonstrate that periodic, time-varying recharge
rates can be estimated from hydrologic time series such as long-term water level records.
The results also demonstrate that periodic recharge estimates were most accurate in
basins with nearly uniform transmissivity, and that the accuracy of the recharge estimates
depended on the monitoring well locations.
16
Draa, Anna, and Richard L. Orndorff. "GIS-Based Analysis of Mountain Block Recharge for Owens Lake Playa, California." Arizona-Nevada Academy of Science, 2003. http://hdl.handle.net/10150/296597.
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Fischer, Sandra. "Exploring a Water Balance Method on Recharge Estimations in the Kilombero Valley, Tanzania." Thesis, Stockholms universitet, Institutionen för naturgeografi och kvartärgeologi (INK), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-92345.
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Simple models that require little input data and are easy to use is the ideal case within hydrology. Basic water balance principles often represent such approaches as the method on rainfall-runoff relationship developed by Sutcliffe et al. in India in 1981. That was tested for the Kilombero Valley in Tanzania in order to estimate the recharge to the soil and sub-surface systems. Measured annual runoff in the streams was compared to the seasonal net rainfall to give the difference as potential recharge. This was done for five separate sub-catchment where the hillslope catchments gave a smaller proportion of the net rainfall to occur as surface runoff compared to the valley-catchments. Due to the difference in hydrologic setting from the original model site in India to the Kilombero Valley (e.g. a wetland and stream type), the soil moisture recharge could not be estimated. Also, corrections are needed to the data preparation process and the state of the original stream flow data is questionable. Thus, the results were interpreted as an indication on how the water resources could be moving in the system. An explaining theory that captured the difference between the landform types is mountain system recharge. That implied that all surplus rainfall generated in the mountains has a potential to eventually recharge the groundwater. The method tested, though its simple general concepts, could not alone give satisfying results for the Kilombero Valley system. However, this study convey the importance of continuous exploration of methods to describe the environment in a simplified way.
18
Buettner, Michael W. "Groundwater manganese study of the Stevens Point Airport wellfield /." Link to full-text, 2006. http://epapers.uwsp.edu/thesis/2006/buettner.pdf.
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Schaffer, Mark Andrew. "Ground-water discharge and aquifer recharge zones near Four Corners, Gallatin County, Montana." Thesis, Montana State University, 2011. http://etd.lib.montana.edu/etd/2011/schaffer/SchafferM0511.pdf.
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The West Gallatin River is closed to new surface water appropriations. Montana law recognizes the potential for new ground-water developments to compromise existing surface-water rights. Determining the effects of new ground-water development upon existing surface-water users requires a detailed understanding of the hydrologic system and the surface and ground water exchanges, which is not available in the Four Corners area of Gallatin County Montana. Hydrologic data was collected during the 2006 water year. Data was collected on stream discharge, streambed hydraulic gradients, temperature, ground-water levels, and specific electrical conductance to characterize zones of upwelling ground water and downwelling surface water. The river and aquifer share a complex hydrologic connection. Some reaches of river gained streamflow from the aquifer and contained zones of downwelling surface water. Other reaches of river which lost water to the aquifer, contained zones of upwelling ground water. Water moved back and forth between the river and aquifer through a variety of hydrologic pathways including; seepage below irrigation canals and irrigated land, drainage ditches from irrigated lands, spring channels, and the porous alluvial riverbed. Ground-water discharge to the stream contributed 8% of the streamflow when no irrigation was occurring in November 2005. In August 2006 during the irrigation season, the volume and relative contribution of ground-water discharge increased to 28% of the streamflow. The data collected from this study was compared to historic water-level data collected during the 1950's and later in the 1990's. This study's analysis benefited from the comparison of surface-water levels to ground-water levels, streambed hydraulic gradients, continuous records of ground-water levels and temperatures from near stream wells. Data from this study indicates that a consistent zone of downwelling surface water was present north of Four Corners which had not been identified in past surveys. However, the baseline data was found to be insufficient for a comparison to this analysis due to a lack of surface water data collected in the previous studies. As a result, it remains unclear whether the zone of downwelling has always been present or represents a change to the hydrologic system at Four Corners.
20
Woodhouse, Elizabeth Gail. "Perched water in fractured, welded tuff mechanisms of formation and characteristics of recharge /." Diss., The University of Arizona, 1997. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_e9791_1997_87_sip1_w.pdf&type=application/pdf.
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Eilers, V. H. M. "The estimation of groundwater recharge by soil water balance in semi-arid regions." Thesis, Cranfield University, 2002. http://dspace.lib.cranfield.ac.uk/handle/1826/4215.
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Quantification of groundwater recharge is a crucial prerequisite for sustainable groundwater resource management, particularly in semi-arid areas where there are large demands for groundwater supplies. This research presents an alternative approach for recharge estimation based on the soil water balance technique. The purpose is to develop a model which provides a suitable balance between physical credibility and data which realistically can be gathered. A spreadsheet model was written based on the conceptual representation of the principal physical processes which actually affect recharge in a semi-arid area. Alternative procedures were included in order to represent: (a) the estimation of runoff, (b) the inclusion of the period with predominant bare soil evaporation and (c) the accounting for evapotranspiration following rainfall on dry soil. The model was tested using real data from a semi-arid region (Northeast Nigeria) making use of selected periods of days and years in order to illustrate the principal model characteristics. The results were presented in the form of diagrams and graphs helping to visualise the interactions between the physical components and the effect of the additional procedures on recharge estimation. The credibility of the model was investigated using an alternative concept of 'analysis of plausibility'. This concept makes use of as wide as possible a range of quantitative and qualitative information from the hydrological system in order to verify the robustness of the model when extensive datasets required by conventional validation techniques are not available. The results suggested that the modelled recharge is physically sound and it is in line with the overall determination of recharge in semi-arid areas by a range of methods. The soil water balance model was utilised to explore important aspects of recharge in semi-arid regions showing the effect of the field variability on the model's output. The preliminary results show that the developed concept reasonably represents the inherent field variability, thus corroborating the strength of the approach for recharge estimation in semi-arid regions.
22
Juhna, Talis. "Sorption of humic substances and microbial activity in the course of artificial recharge of groundwater." Licentiate thesis, Luleå tekniska universitet, 1999. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-17644.
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Sorption of humic subtances and metal-humate complexes on aquifer material taken from basins used for artificial recharge of groundwater was studied in batch scale experiments. Distribution of bacteria attached to the material from uppermost layer and from the horizons below the infiltration basin were measured in the field studies. Sorption of aquifer material was heterogeneous in respect to the different position and depth in the infiltration basin. Sorption depended on the numerous factors including composition of the filter sand and properties of humic matter. The heavy metals retarded during artificial groundwater recharge was in the form of metal-humate complexes, dominantly in anionic form or as particulate matter. Sorption of humic substances on the aquifer material was substantially enhanced due to the forming of complexes with heavy metals. Total bacterial number was greatest on the upper most layer of infiltration basin. Slight decreases of bacterial number was observed down to the depth of two meters. There were no significant differences in ratio among major physiological groups of heterotrophic bacteria between layer investigated. The smallest seasonal variation of bacteria was found in the deeper layer below infiltration basin.Godkänd; 1999; 20070403 (ysko)
23
Daly, Matthew H. "Hydrogeochemical response of acid-producing mine spoil aquifer to induced alkaline recharge." [Morgantown, W. Va. : West Virginia University Libraries], 1998. http://etd.wvu.edu/templates/showETD.cfm?recnum=180.
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Thesis (M.S.)--West Virginia University, 1998.Title from document title page. Document formatted into pages; contains ix, 137 p. : ill. (some col.), maps (some col.). Includes abstract. Includes bibliographical references (p. 117-124).
24
Cluff, C. Brent. "El Obeid Water Supply/Water Harvesting Potential in Western Sudan: Report to Western Sudan Agricultural Research Project, Washington State University, College of Agriculture & Home Economics." Water Resources Research Center, University of Arizona (Tucson, AZ), 1985. http://hdl.handle.net/10150/308906.
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Introduction: A trip was taken from July 3 to July 17, 1985 to Sudan to study the El Obeid compartmented reservoir system. This system supplies most of the domestic water for the city of El Obeid which has a population of 200,000 to 250,000 people. This water supply was exhausted in March of 1985 and the town was out of water until the monsoon rains began July 2, 1985. Approximately one week was spent in El Obeid and Kadugli. The remainder of the time was spent in Khartoum where the IBM PC was used. Some time was also spent in Khartoum in obtaining flattened ceramic spheres for evaporation control.
25
Abe, J. M., and B. C. Saliba. "Economic Feasibility of Artificial Recharge and Recovery of Imported Water in Butler Valley, Arizona." Arizona-Nevada Academy of Science, 1985. http://hdl.handle.net/10150/296365.
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From the Proceedings of the 1985 Meetings of the Arizona Section - American Water Resources Association and the Hydrology Section - Arizona-Nevada Academy of Science - April 27, 1985, Las Vegas, Nevada
26
Guldan, Nathan M. "Relationships between groundwater recharge dates, nitrate levels, and denitrification in a central Wisconsin watershed /." Link to Abstract, 2004. http://epapers.uwsp.edu/abstracts/2004/Guldan.pdf.
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Assefa, Kibreab. "Groundwater recharge modelling: linkage to aquifers and implications for water resources management and policy." John Wiley & Sons, 2013. http://hdl.handle.net/1993/22212.
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The main goal of this research is to develop and test a groundwater recharge estimation method that can address some of the key research priorities in groundwater. In this context use is made of various modelling tools including ArcGIS, field data (in situ observations of soil temperature and soil moisture), and soil physics as represented by a physically based vadose zone hydrologic model (HYDRUS-1D). The research is conducted in a pilot watershed in north Okanagan, Canada.
The public version of HYDUS-1D and another version with detailed freezing and thawing module are first used to investigate seasonal distribution of heat and water movement in the vadose zone. Model performance is evaluated in different scales by using field data, the gradient-based optimization algorithm of HYDRUS-1D, and ROSETTA derived prior information about soil hydraulic parameters. The latter are fitted to statistical distributions and used in Monte-Carlo experiments to assess the potential uncertainty in groundwater recharge due to model parameters. Next, the significance of the recharge estimation method for catchment scale transient groundwater modelling is demonstrated by applying uniform and variable flux boundary condition to a saturated zone transient groundwater model, MIKESHE. The results showed that the traditional uniform recharge assumption can lead to misleading decisions related to water resources management and pumping well network design.
The effect of pumping well network and the provincial Water Act on water resources sustainability are further examined in an evolving climate. The results suggest potential water resource problem in the basin, which can possibly be attributed to the previously installed pumping well network (depth and screen level), and the provincial water use policy. The findings of this study demonstrate that such problems related to inappropriate well network and water resource management can greatly be minimised with the use of the recharge estimation method developed in this study.
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Frycklund, Cristina. "Artificial recharge of groundwater for public water supply : potential and limitations in boreal conditions /." Stockholm, 1998. http://www.lib.kth.se/abs98/fryc0605.pdf.
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Choodegowda, Ravikumar B. "Modeling small reservoirs in the Great Plains to estimate overflow and ground-water recharge." Diss., Kansas State University, 2009. http://hdl.handle.net/2097/4610.
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Doctor of PhilosophyDepartment of Biological & Agricultural Engineering
James K. Koelliker
Small reservoirs catch and store water for long periods and they decrease streamflow and increase ground-water recharge. A field monitoring program provided the measured water depth for four years in several reservoirs in the Republican River Basin where there are concerns about their aggregate effects in the basin. The daily water budget operation for one reservoir was developed. Daily seepage rates were estimated by using precipitation, inflow and evaporation which was assumed equal to grass reference evapotranspiration (ET0), that average 120 to 150 cm/yr, along with the measured stage-storage and stage-surface area relationships. Two computer simulation modules, written in FORTRAN 95, were developed to estimate 1) overflow and gross seepage and 2) potential for ground-water recharge underneath the reservoir. Required daily input data are precipitation, ET0, and inflow from the watershed area. Required reservoir site characteristics include stage-storage and stage-surface area relationships, a standard seepage rate (S0) at 14 different levels in the reservoir, soil-water and plant-growth characteristics and a monthly crop-residue factor. The gross seepage module calculates water depth that determines daily overflow, the water-surface area for evaporation and the head of water on the 14 levels to cause seepage losses. If a level is not inundated, seepage is zero. If a level is inundated less than 0.3-m, S0 is used. When the water head (hL) on a level exceeds 0.3 m, the seepage rate (SL) is increased by, SL = S0 * (hL/0.3)0.25. This relationship was chosen after testing several exponent values between 0 and 1. The modules were calibrated on one reservoir and verified on two others in northwestern Kansas. Results showed runoff from the watersheds averaged about 1.2 to 1.6 cm/yr from the average annual precipitation of 46 to 62 cm. The three reservoirs reduced streamflow at the reservoir site by 74 to 97%, but 90 to 95% of the retained runoff was calculated to contribute to ground-water recharge. Several sensitivity analyses for model inputs were done. Results showed that, the ratio of the average annual inflow volume from the watershed area to the reservoir storage volume was the most sensitive input variable tested.
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Wright, Alan. "The artificial recharge of urban stormwater runoff in the Atlantis coastal aquifer." Thesis, Rhodes University, 1992. http://hdl.handle.net/10962/d1005491.
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The thesis covers the investigation of the storm water runoff and artificial recharge components of the Atlantis Water Resource Management Scheme in the Southwestern Cape. The objective of the study was to obtain an in-depth knowledge of the process of artificial recharge of urban storm water runoff, in order to identify the most efficient recharge management strategy for the Atlantis aquifer. To achieve the objective it was necessary to first study the existing knowledge on urban storm water hydrology and artificial recharge by spreading, and to create a conceptual model of what might be expected. The study area was then investigated to examine how closely the actual situation was reflected by the conceptual model, enabling recommendations to be made for the sound management of the system. The stormwater runoff component was found to differ from most urban hydrological studies as a result of its large baseflow component. The sandy nature of the catchment, small percentage area of effective impervious surface, and high groundwater table resulted in the baseflow constituting more than 40% of the total storm water runoff and accounting for over 60% of the pollution load. The "first flush" effect established as a major source of pollution in other studies, was found to be of minor significance in this study area. The overall stormwater quality (excluding the noxious industrial baseflow) was found acceptable for artificial recharge within the study area, although the baseflow from the industrial sub-catchments showed the potential for being a major source of pollution in the future. The treated wastewater used for artificial recharge prior to 1987 was found to be unacceptable for recharge purposes. The treated industrial effluent should under no circumstances be recharged up-gradient of the Witzand well field. The treated domestic effluent although of a poorer quality than the resident Witzand well field groundwater could be recharged in order to boost recharge volumes and form a buffer against further intrusion by the poor quality groundwater from the Brakkefontein area. This would however only be acceptable if strict water quality control is maintained and recharge does not take place west of the present basin. The recharge basin was found to be well situated with respect to influencing the Witzand wellfield and maintaining a groundwater buffer against poor quality groundwater flow from the northeast towards the central area of the wellfield. Unfortunately the surrounding low-lying topography and sandy retaining walls have resulted in return flow and raised groundwater-levels. The raised groundwater mound does not comply with the conceptual model and together with the sandy nature of the unsaturated zone resulted in less effective purification during infiltration. The practice of letting large portions of the basin floor dry-out during summer was shown to be beneficial and the periodic cleaning of the deeper portions of the basin essential. The artificially recharged water was found to have influenced the upper portion of the aquifer well beyond the West Coast Road. The study of groundwater quality being a good method for tracing artificially recharged water. The groundwater quality has improved as a result of artificial recharge since the removal of treated wastewater from the recharge basin. The groundwater was (ii) found to be very responsive to the slightest changes in recharge basin water quality or/and quantity. Management of the recharge basin therefore had to be very much of a compromise between qualitative and quantitative approaches. The present approach of recharging all the stormwater runoff throughout the year providing the most efficient compromise under the present conditions. The study revealed that the most efficient recharge management strategy would be the recharge of treated domestic sewage effluent in the present recharge basin and all residential storm water runoff plus industrial "storm flow" stormwater runoff in a new recharge basin located northwest of the present basin. Strict water quality control must be maintained on the water discharged into the basins and an annual wet/dry cycle implemented within the basins to boost infiltration. The entire system should continue being monitored to safe guard the groundwater resource from pollution and over exploitation.
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Frey, Andreas. "Groundwater recharge and pesticide leaching in a Triassic sandstone aquifer in South-West England." Thesis, University of Exeter, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.297614.
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Aykanat, Gokben. "Effects Of Precipitation Recharge And Artificial Discharge On Salt Water-fresh Water Interface Movement In Selcuk Sub-basin: Climatic Indications." Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613027/index.pdf.
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Fluctuations in temperature and precipitation amounts due to climate change influence recharge rate of groundwater. Any variations in the amount of precipitation recharge and artificial discharge directly affect groundwater level and so the salt water intrusion rate in the aquifers, which are in contact with sea water. The purpose of this study is to determine the overall historical precipitation recharge trend in Selçuk sub-basin and to detect whether there is a decrease or increase in recharge amounts due to climate change since 1100 BC. Besides, it covers assessing the future position of the salt water-fresh groundwater interface as a result of possible fluctuations in climate and artificial discharge. For this purpose, numerical density dependent cross sectional groundwater flow with solute transport model was conducted using finite element approach. At first, current salt water-fresh water interface and artificial discharge related head changes in the aquifer were determined. Backward modeling was utilized to obtain concentration distribution in the year 1976 representing the last stage of the undisturbed period. Then, progradation of salt water-fresh water interface since 1100 BC to 1976 was modeled using calibrated parameters and current recharge value. As a result of sea-regression model simulations (1100 BC-1976) less degree of salt water intrusion than that of currently detected in the area was obtained. The result suggests that overall recharge amount in the last 3076 years must have been less than that of 1976. Moreover, future (2010-2099) position of the interface and head changes under the influence of both climate change and increasing water demand were determined. Future model simulations indicate that salt water-fresh water interface moves farther landward. However this movement is mostly due to increasing discharge amount rather than that of climatic changes.
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Schilling, Keith Edwin. "Hydrological processes inferred from water table fluctuations, Walnut Creek, Iowa." Diss., University of Iowa, 2009. https://ir.uiowa.edu/etd/430.
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In a shallow aquifer underlain by low permeable material, groundwater recharge (R), discharge to rivers or stream as baseflow (BF), and discharge to the atmosphere as evapotranspiration (ET) are related by a simple water balance equation, R - ET - BF = ΔS. Gathering information about these processes is difficult since these processes are hidden from view, yet these processes commingle with one another at the water table surface. The main objective of this dissertation project was to evaluate how main hydrological processes can be inferred from high-resolution water table measurements collected at various sites in Walnut Creek watershed located in southern Iowa. Water table monitoring data available for analysis in the project included three main sites, covering 2573 days between 1996 to 2008 and 61,714 individual water level monitoring points. Water table fluctuations were used to estimate R across an upland-floodplain chronosequence and plant ET under three riparian land covers. High resolution hydraulic head measurements were analyzed with spectral methods to evaluate potential surface and groundwater interaction. Detailed sedimentology and water table monitoring were combined to develop a conceptual model of nitrate leaching to in the near-stream riparian zone of an incised channel. Additional soil moisture and precipitation monitoring are recommended for improved application of methods to other sites. Results from this dissertation indicate that there is a considerable amount of information about key hydrological processes to be gained by measuring water table levels at a high frequency.
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Reed, Deborah A. "Spatial and temporal biogeochemical changes of groundwater associated with managed aquifer recharge in two different geographical areas /." Connect to this title, 2007. http://theses.library.uwa.edu.au/adt-WU2008.0074.
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Barba, Ferrer Carme. "Physical, geochemical and microbial parameters driving the improvement of water quality in managed aquifer recharge." Doctoral thesis, Universitat Politècnica de Catalunya, 2018. http://hdl.handle.net/10803/671103.
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Worldwide water demand has been increasing over time, mainly due to population growth and society development. In addition, climate change is causing a significant alteration of the periodicity and intensity of precipitation and climate related events. All this implies significant challenges for a sustainable exploitation of water resources specially during water scarcity periods.
Therefore, Managed Aquifer Recharge (MAR) represents a feasibly solution to deal with future water management challenges through the storage of available water in aquifers.
The present dissertation is focused on the study of microbial, biogeochemical and physical processes related to MAR ponds, regarding both quantity and quality aspects. The knowledge about these processes has allowed to identify key issues affecting the correct operation of infiltration ponds, laying the foundations for the optimization of quantity and quality targets.
Two different sites in Llobregat River Basin were chosen as a investigation framework.
The first part of this thesis was developed in Sant Vicenç dels Horts MAR system (Barcelona), where an innovative treatment for emerging contaminants had been proved successfully. A reactive layer was put in the bottom of infiltration pond, promoting different redox conditions below the pond and enhancing the removal of dissolved organic matter as well as emergent organic contaminants. In this thesis, further work has been carried out, by investigating the role of microbial community in this removal, by means of a microbial fingerprinting study between two different scenarios. Which were (1) when no-recharge was present and (2) during a long recharge period. The microbial fingerprinting study confirmed that microbial diversity during recharge period fitted in Intermediate Disturbance Hypothesis approach. Furthermore, sequencing of prominent bands evidenced the presence of principally degradative-like microorganisms during recharge. A multivariate statistical analysis including hydrochemical, soil grain-size distribution, operational and microbial variables was also performed. Most relevant variables affecting microbial populations were identified. Likewise, the correlations between some microbial prints in the system revealed the presence of some classes and species involved in biodegradation pathways.
The second investigation was focused on the study of redox processes from the infiltration pond to the aquifer, passing through the vadose zone. The study was placed in Castellbisbal MAR system (Barcelona). This facility has a conventional surface infiltration pond without the effect of the reactive layer. The infiltration path was widely monitored and four sampling campaigns were carried out in four different moments along a one-year study. Results from in situ redox potential measurements, temperature evolution, operating conditions (water levels, flow rate and infiltration rate), characterization of the organic matter and hydrochemical composition of water were collected and analyzed. Especially, operating conditions and redox potential, where it was observed that evolution in the first meter of the infiltration profile had been related to clogging development in the pond bottom.
Finally, results from monitoring tasks were used as the basis to construct a flow and heat transport model simulating recharge process. The flow model included the decrease of hydraulic conductivity caused by clogging periods. In addition, a heat transport model was capable to calculate the modifications of hydraulic conductivity due to temporal temperature evolution. Taking into account results of heat transport model, two batch-type biogeochemical models were suggested to explain redox processes in winter and summer scenarios. Furthermore, models were capable to explain the fate of the different fractions of dissolvedLa demanda d’aigua arreu del món es preveu que continuarà augmentant a causa de l'increment de la població i el seu desenvolupament. El canvi climàtic, a més, suposarà un agreujant, ja que es preveu que alterarà la periodicitat i intensitat de les precipitacions arreu. Tot aquest marc fa que la gestió sostenible dels recursos hídrics esdevingui tot un repte, especialment durant possibles episodis de sequera. La recàrrega induïda dels aqüífers representa uns solució vàlida per emmagatzemar aigua al subsòl, i per tant, assolir alguns dels reptes que la gestió de recursos hídrics presenta. La present tesi doctoral té com a objectiu l’estudi de processos microbiològics, biogeoquímics i físics relacionats amb les basses de recàrrega. Tot aquest coneixement ha permès detectar molts dels aspectes que afecten el correcte funcionament d’aquestes infraestructures, construint les bases per a poder optimitzar-ne el funcionament. S'han triat dos emplaçaments de recàrrega induïda a la Conca del Riu Llobregat com a marc d'investigació. La primera part de la tesi s'ha efectuat al sistema de recàrrega de Sant Vicenç dels Horts (Barcelona), on hi ha instal·lada una barrera reactiva que afavoreix la degradació de contaminants emergents. Allà, s’ha investigat el paper de les comunitats microbianes mitjançant un estudi de patrons microbiològics comparant dos escenaris diferents. S’ha avaluat la contribució de les comunitats microbianes sota els efectes prolongats de la recàrrega i amb la bassa parada. Aquest estudi confirma que els efectes de la recàrrega sobre la diversitat microbiana es podrien assimilar als predits per la Hipòtesi de la Pertorbació Intermèdia. Així mateix, la seqüenciació de les bandes més prominents ha revelat que les espècies principals de microorganismes que es trobaven sota els efectes de la recàrrega tenien capacitats degradatives. A continuació s’ha efectuat un estudi estadístic multivariant, englobant variables de tipus hidroquímic, de mida i distribució de gra en sòls, de tipus operacional i microbiològiques. S’han identificat doncs, les variables més rellevants que afecten les poblacions microbianes. A més, s’han detectat correlacions entre algunes variables hidroquímiques i espècies com ara desnitrificants o metanòtrofes. La segona part de la tesi ha estat emmarcada en el sistema de recàrrega de Castellbisbal (Barcelona). Aquest sistema inclou també una bassa d’infiltració, però sense l’efecte d’una capa reactiva. A Castellbisbal s’han estudiat els processos redox en tot el perfil d’infiltració, des de l’aigua d’infiltració fins a la zona saturada de sota la bassa, passant per la zona no saturada. Tot aquest perfil es va monitoritzar i es van dur a terme quatre campanyes de mostreig durant l’any sencer que ha durat l’estudi. La monitorització ha permès obtenir resultats d’evolució de potencial redox a diferents profunditats, de la temperatura i de tots els paràmetres d’operació (nivells, cabals i taxa d’infiltració). Les campanyes de mostreig han permès caracteritzar hidroquímicament les mostres així com també caracteritzar l’origen de la matèria orgànica present. La integració de tots aquests resultats, especialment pel que fa a la monitorització del potencial redox en el primer metre de sòl ha permès evidenciar la relació que tenen tots ells amb la colmatació al llit de la bassa. El model evidencia la importància de la temperatura en els paràmetres hidràulics. Partint d’aquesta base, s’han desenvolupat dos models biogeoquímics de tipus batch amb l’objectiu d’explicar els processos redox en dos escenaris estiu-hivern. Els models, a més, inclouen diferents fraccions de matèria orgànica dissolta: de caràcter làbil, recalcitrant i una tercera, d’immòbil. S’avaluen, doncs, els canvis en les taxes de degradació de la matèria orgànica a causa de les variacions de temperatura
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Vandemoer, Catherine 1955. "The hydrogeochemistry of recharge processes and implications for water management in the southwestern United States." Diss., The University of Arizona, 1988. http://hdl.handle.net/10150/191146.
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A geochemical approach to the evaluation of the chemistry of natural recharge processes in the Tucson basin was used to identify the major minerals controlling the evolution of ground water chemistry and to assess the viability of recharging imported Central Arizona Project water supplies. Well cuttings analyses and water quality samples from over 65 wells in the basin were used as input to the geochemical computer model PATH4 (Helgeson, 1970) and the sequence of aqueous species and mineral production in a recharge reference volume examined. The study reveals that natural processes in the basin lead to the increase in dissolved solids content in ground water over time and the production of secondary minerals such as calcite, calcium montmorillonite, kaolinite and poorly crystallized alumino-silicate phases. Secondary minerals grow into aquifer pore spaces and may, over time, be responsible for the reduction in aquifer porosity and the specific capacity of wells. The recharge of imported Central Arizona Project water will lead to an increase in the dissolved solids content of ground water and may, in certain areas of the basin, lead to the enhanced production of secondary minerals. The use of CAP water as a recharge source must be guided by the geochemical factors which influence the nature and scope of reactions between CAP water and the Tucson aquifer matrix. The study demonstrates the need for and identifies water quality and aquifer matrix criteria for the assessment of sources of recharge water and recharge facility sites. The use of geochemistry as a tool for quantitatively assessing ground water quality is demonstrated.
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Barger, Erin E. "Migration of Recharge Water Downgradient from the Santa Catalina Mountains into the Tucson Basin Aquifer." Thesis, The University of Arizona, 1996. http://hdl.handle.net/10150/249235.
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Aquifers in the arid alluvial basins of the southwestern U.S. are recharged predominantly by infiltration from streams within the basins and by water entering along the margins of the basins from surrounding mountains (mountain -front recharge). The Tucson Basin of Southeastern Arizona is such a basin. The Santa Catalina Mountains form the northern boundary of this basin and receive more than twice as much precipitation (about 70 cm/yr) as the basin does (about 30 cm/yr). In this study environmental isotopes were employed to investigate the migration of precipitation basinward through joints and fractures. Water samples were obtained from springs in the Santa Catalina Mountains. Stable isotopes and thermonuclear bomb-produced tritium enabled qualitative characterizations of flow paths and flow velocities. Stable isotopic measurements fail to display a direct altitude effect. Tritium values indicate that although a few springs discharge pre-bomb water, most springs discharge waters from the 1960's or later.
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Nicholas, Hillary Dianne. "Estimating Surface Water Presence and Infiltration for Intermittent Streams in the Semi-arid Southwest." Thesis, The University of Arizona, 2012. http://hdl.handle.net/10150/238891.
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Ephemeral streams with spatially and temporally variable flow are important ecological settings in semi-arid desert environments that until now have been poorly characterized. Our quantitative analysis explores how intermittent stream hydrology varies across geomorphic (mountain streams to desert washes) and climatic gradients (150-400 mm precipitation) in Southern Arizona. Stream channels were instrumented for the first time with a co-deployment of vertical profiles of subsurface temperature sensors, and electrical resistance (ER) sensors on the bed surface. HYDRUS 1-D was used to simulate vertical unsaturated flow, and differences along hydrologic, topographic, and climatic gradients were compared. Annual surface water presence varied < 1%-82% of the year, and reach-normalized infiltration water volumes were 20,000-2,500,000 m³/(km y). Surface water presence was correlated with geomorphic gradient, and infiltration volumes were correlated with surface water presence. This sensor co-deployment method has shown that ER sensors alone are necessary to estimate infiltration in semi-arid, poorly-sorted, coarse desert channels.
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Sun, Xianfeng. "A water balance approach to groundwater recharge estimation in Montagu area of the Western Klein Karoo." Thesis, University of the Western Cape, 2005. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=init_4142_1178702615.
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This aim of this study was to improve the understanding and functioning of the Table Mountain Group aquifer system and contribute to the sustainable development of this potential source for water supply in the Montagu area.
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Rosenqvist, Lars. "Afforestation of former arable land in north-western Europe : nitrate leaching, carbon sequestration and water recharge /." Uppsala : Dept. of Forest Soils, Swedish University of Agricultural Sciences, 2007. http://epsilon.slu.se/200702.pdf.
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Sutton, Justin Corser IV. "Groundwater Recharge Areas: Identification and Protection within the Central Coast Regional Water Quality Control Board Jurisdiction." DigitalCommons@CalPoly, 2011. https://digitalcommons.calpoly.edu/theses/584.
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This master’s project was conducted under the direction of the Central Coast Regional Water Quality Control Board (Water Board) to assist with augmenting their Basin Plan. An investigation of the current practices for identifying and managing groundwater recharge areas was conducted, and strategies for protecting water quality by managing land uses in groundwater recharge areas were developed. Data sources included a review of agency documents, websites, and maps; interviews with stakeholders, and literature research. Data from these sources provided the foundation on which to base strategies for maintaining and improving groundwater quality in the Central Coast Hydrologic Region. This project recommends standard language for groundwater recharge areas, minimum criteria for identifying and mapping these areas, and protection strategies. The Water Board must establish minimum standards to protect groundwater recharge areas, and collaborate with local agencies to protect the quality of groundwater throughout their jurisdiction.
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Schilling, Keith Edwin Zhang You-Kuan. "Hydrological processes inferred from water table fluctuations, Walnut Creek, Iowa." [Iowa City, Iowa] : University of Iowa, 2009. http://ir.uiowa.edu/etd/430.
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Esposito, David M. "Hydrogeochemistry of stream channel recharge of sewage effluent, northwest of Tucson, Arizona." Diss., The University of Arizona, 1993. http://hdl.handle.net/10150/191176.
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This investigation has documented the water quality impacts of stream channel recharge of sewage effluent northwest of Tucson and has evaluated the hydrogeochemical mechanisms potentially responsible for observed water quality changes. The evaluation was accomplished partly through construction of twelve monitor wells and implementation of a quarterly water quality monitoring program for surface water and groundwater. Constituents monitored included major inorganic chemical constituents, trace inorganics, trace metals, priority pollutants/trace organics and microbiological contaminants. ¹⁵N also proved useful in the study. The significance of a reducing zone immediately beneath the bed of the Santa Cruz River with respect to denitrification was documented. Findings of this investigation indicate that while sewage effluent is of poor quality with respect to drinking water standards, groundwater recharged by sewage effluent is of improved quality. Other findings include: * Nitrate in shallow groundwater near the Santa Cruz River in the Cortaro area appears to be primarily from stream channel recharge of sewage effluent; * Nitrate-N contents of effluent recharged groundwater averaged about 5 mg/1, well below the maximum contaminant level for drinking water of 10 mg/1, representing a 75 percent loss in total nitrogen during stream channel recharge of sewage effluent (assuming no mixing); * Both stream channel recharge of sewage effluent and agricultural deep percolation contribute to nitrate in shallow groundwater near the Santa Cruz River in the Marana area; * The reducing zone beneath the Santa Cruz River may be responsible for denitrification losses of up to 5 mg/1 of nitrate-N. This would explain approximately 30 percent of nitrogen losses, on average, between effluent and recharged groundwater; * The mechanisms of cation exchange and mixing with groundwater from other sources can explain the major changes in water quality between effluent and groundwater with respect to major inorganic chemical constituents; * Renovation of effluent with respect to coliform bacteria and enteric viruses content during recharge is not complete.
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Palmqvist, Larsson Karin. "Soil Management Strategies to Establish Vegetation and Groundwater Recharge when Restoring Gravel Pits." Licentiate thesis, KTH, Land and Water Resources Engineering, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-1692.
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The removal of vegetation and overburden changes the naturalwater purifying processes and thus decreases the groundwaterprotection in gravel pit areas. The sand and gravel depositsusedfor aggregate extraction in Sweden are also often valuablefor extraction of groundwater as a drinking water resource. TheSwedish legislation requires that gravel pits be restored afterthe cessation of extraction, the aim being to reestablishvegetation and to reinstate groundwater purifyingprocesses.
The objective of this study was to improve our understandingof the processes governing groundwater protection andvegetation establishment so that these could be applied toimproving restoration methods for reestablishing naturalgroundwater protection. The focus was on the importance of soilphysical properties of the topsoil for vegetation establishmentand groundwater recharge.
Actual field methods for restoration were reviewed.Conflicts between aggregate extraction and groundwaterinterests were common. In many cases the actual restorationcarried out differed from pre-planned specifications in permitdocumentation.
Commonly available substrates that might be used forrestoration of gravel pits were investigated. The soils weredescribed as regards texture, organic content, porosity, waterretention and hydraulic conductivity. The way in which acombination of the water retention characteristic and theunsaturated conductivity influenced the behaviour of thesoil-plant-atmosphere system was demonstrated using aprocess-orientated simulation model. Plants with well-developedaboveground characteristics and shallow roots in particularexerted the highest requirements on the soil physicalproperties.
Key words:groundwater protection, soil physicalproperties, CoupModel, unsaturated conductivity, waterretention, transpiration, soil evaporation
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Woocay-Prieto, Arturo. "Groundwater hydrochemical facies, flowpaths and recharge determined by multivariate statistical, isotopic and chloride mass-balance methods." To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2008. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.
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Kasper, Joshua W. "Simulated ground-water flow at the Fairmount Site, Sussex County, Delaware (USA), with implications for nitrate transport." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 145 p, 2007. http://proquest.umi.com/pqdlink?did=1253509881&Fmt=7&clientId=79356&RQT=309&VName=PQD.
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Nickall, Enéz Sarah-Leigh. "The feasibility of artificial recharge of the Bushmans River Mouth Aquifer." Thesis, Nelson Mandela Metropolitan University, 2008. http://hdl.handle.net/10948/704.
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The main aim of the project is to investigate the feasibility of artificial recharge of the Bushmans River Mouth Aquifer in the Eastern Cape. The suggested method of recharge is through natural infiltration through a series of wetlands in the back dune area. The proposed site was the Klipfontein Vlei which is located just north of the Bushmans River Mouth. Artificial recharge is defined as augmenting the natural movement of surface water into underground formations by some method of construction, the spreading of water, or by artificially changing natural conditions. A variety of methods have been developed, including water spreading, recharging through pits and wells, and pumping to induce recharge from surface water bodies. The choice of a specific method is controlled by local topography, geology and soil conditions, and the quantity of water to be recharged and ultimate water usage. In special circumstances, land value, water quality, and climate play an important role. Artificial recharge is not a foreign concept to South Africa and this project is to test its feasibility in a back dune wetland area. Augering done in the study area revealed the dominance of sandy loam in the upper layers of the pans, loamy sand in the middle levels and the presence of some sand lenses in the lower reaches. Particle size analysis done by sieving and hydrometer test, showed a dominant 3f fraction. There was variation in modes in pan 1 from unimodal to bimodal to trimodal. Pan 2 showed no variation as all samples were unimodal and moderately well sorted. Infiltration tests were done by a double ring infiltrometer. These results showed that the infiltration rates of the pans became stable after 15 to 20 minutes, thus indicating that the soil had reached its saturation point. The resistivity surveys revealed a stepped water table. The inclination of the water is controlled by the predominately argillaceous horizons of the Bokkeveld Group. Based on the above results, it is recommended that the Klipfontein Vlei be used as an artificial recharge site.
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Glendenning, Claire. "Evaluating the impacts of rainwater harvesting (RWH) in a case study catchment: The Arvari River, Rajasthan, India." Faculty of Agriculture, Food and Natural Resources, 2009. http://hdl.handle.net/2123/5835.
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Doctor of Philosophy(PhD)In many areas of India, increasing groundwater use has led to depleted aquifers. Rainwater harvesting (RWH), the small scale collection and storage of runoff to augment groundwater stores, is seen as a solution to the deepening groundwater crisis in India. However while the social and economic gains of RWH have been highlighted, there has not yet been a thorough attempt to evaluate the impacts of RWH on larger catchment hydrological balances. The thesis here will endeavour to address this research gap through a case study of the 476 km2 ungauged semi-arid Arvari River catchment in the state of Rajasthan. Over 366 RWH structures have been built in this catchment since 1985 by the community and the local non-government organisation (NGO), Tarun Bharat Sangh (TBS). The local effects of RWH structures and general catchment characteristics were determined through field investigations during the monsoon seasons of 2007 and 2008. The analysis described large variability in both climatic patterns and recharge estimates. Potential recharge estimates from seven RWH storages, of three different sizes and in six landscape positions, were calculated using the water balance method, which were compared with recharge estimates from water level rises in twenty-nine dug wells using the water table fluctuation method. The average daily potential recharge from RWH structures is between 12 – 52 mm/day, while recharge reaching the groundwater was between 3 – 7 mm/day. The large difference between recharge estimates could be explained through soil storage, and a large lateral transmissivity in the aquifer. Approximately 7% of rainfall is recharged by RWH in the catchment, which is similar in both the comparatively wet and dry years of the field analysis. This is because the capacity of an individual structure to induce recharge is related to structure size and capacity, catchment runoff characteristics and underlying geology. Due to the large annual fluctuations in groundwater levels, the field study results suggest that RWH has a large impact on the groundwater supply, and that there is a large lateral flow of groundwater in the area. The results inferred from the field analysis were then applied to a conceptual water balance model to study catchment-scale impacts of RWH. An existing model was not used because of the paucity of data, and the need to incorporate an effective representation of RWH function and impact. The model works on a daily time step and is divided into subbasins. Within the subbasin hydrological response units (HRUs) describe the different land use/soil combinations associated with the Arvari River catchment, including irrigated agriculture. Sustainability indices, related to water from groundwater and rainfall for irrigated agriculture demand, were used to compare scenarios of management simulated in the conceptual model. The analysis shows that as RWH area increases, it reaches a limiting capacity from where developing additional RWH area does not increase the benefit to groundwater stores, but substantially reduces streamflow. This limiting capacity was also seen at the local-scale, where cumulative potential recharge from an individual RWH structure reaches a maximum daily recharge rate. These results could have important implications for RWH development, but require further research. The analysis highlighted the important link between irrigation area and RWH area. If the irrigation area is increased at the optimal level of RWH, where the sustainability indices were greatest, the resilience of the system actually decreased. Nevertheless RWH in a system increased the overall sustainability of the water demand for irrigated agriculture, compared to a system without RWH. Also RWH provided a slight buffer in the groundwater store when drought occurred. While RWH addresses the supply-side issues of groundwater operation, the institutions that form rules for groundwater use must also be considered, because of the link between irrigation area and RWH. The Arvari River Parliament, the community-based group in the case study area, was examined according to Ostrom’s factors for collective action. It was found that the major limitation for the effectiveness of this group was the minimal information available about the aquifer characteristics.
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Ayuso, Gabella Maria Neus. "Risk Assessment and Risk Management in Managed Aquifer Recharge and Recycled Water Reuse: The Case of Sabadell." Doctoral thesis, Universitat de Barcelona, 2015. http://hdl.handle.net/10803/379309.
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The increasing practice of water recycling, including or not managed aquifer recharge (MAR), requires to thoroughly assess the risks posed by it in real systems, not only in laboratory and column studies.
The present work has been developed in a case study in Sabadell, Spain. For this site, the treated effluent of the Ripoll River WWTP is discharged into the Ripoll River, thus enhancing the natural infiltration to the alluvial aquifer. Pumping of the groundwater induces a riverbed filtration process (RBF), which is one of types of MAR. The recovered water undergoes further post-treatments, including UV, chlorination and sand filtration. After the post-treatments, the water is used for park irrigation and street cleaning. This site was part of the RECLAIM WATER project, supported by the European Commission and devoted to studying MAR and the use of reclaimed water for it in different locations in Europe, as well as in other countries outside Europe. For Sabadell case study, named “RISMAR” in the present work, a risk assessment and a risk management have been developed. In addition, a quantitative microbial risk assessment (QMRA) has been developed too. QMRA is not as usually applied to recycled water schemes as it is to drinking water ones, and even less to MAR.
In order to develop the risk assessment, it was necessary to gather data on the site. Most of the data used to develop the present work were generated in the framework of the RECLAIM WATER project, and it included not only basic wastewater and surface water regular parameters and microbiological indicators, but also trace compounds, pathogens and antibiotic resistance genes. Other data were available from public institutions and previous works.
The main results of the risk assessment indicate that for the uses considered for the final treated water the risk is low and in some cases medium, with the exception of using the final treated water as drinking water. Currently, this use it is not in place at the site, and it is not expected to be in the near future. The QMRA results additionally indicate that cross-connection, swimming and the immunocompromised population would be in the limit of the acceptable level of risk. Thus, the immunocompromised population should be considered in risk assessments, as the risk for them might be much higher than for the rest of the population. The residual risks that needed to be managed and considered were posed by inorganic compounds, organic compounds, salinity and mobilization of inorganic compounds from the sediments.
Another important result of the work is that the RBF and subsurface treatment proved to be very useful in reducing the risks posed by pathogens, nutrients, organic compounds and particulates. In contraposition, other risks appeared, like the mobilization of inorganic compounds from the aquifer. Then, these positive results support the request by many authors of treating MAR as an additional treatment.
Finally, a risk management plan has been developed, integrating the results of the risk assessment. For this risk management plan, not only the critical control points are identified, as it is typical for risk managements, but the twelve elements of the framework issued by the Australian Government (NRMMC-EPHC–NHMRC, 2009) have been assessed and developed, thus supporting a robust risk management plan. Emphasis is put in corrective and preventive actions for the system, as well as in defining the critical limits, monitoring program and sampling points. Besides, validation is given the importance it has in order to ensure a proper functioning of the system.La regeneració d’aigües és una pràctica cada cop més generalitzada, que pot incloure o no recàrrega artificial d’aqüífers (MAR: Managed Aquifer Recharge), i que requereix una avaluació dels riscs en sistemes reals en ús. L’estudi actual es desenvolupà a Sabadell, Espanya. En aquest cas de MAR la recàrrega de l’aqüífer es realitza a través del llit del riu Ripoll i s’utilitza l’efluent secundari d’una depuradora. L’aigua que posteriorment s’extreu de l’aqüífer passa per un tractament ultraviolat, cloració i filtre de sorra, i s’utilitza per al reg de parcs i neteja de carrers. Aquest sistema formà part del projecte europeu RECLAIM WATER. Al present treball s’ha desenvolupat una avaluació i gestió del risc. A més a més, s’ha fet un estudi del risc probabilístic, cosa habitual en aigües potables però no en aigües regenerades o en MAR. Les dades utilitzades per a l’avaluació del risc es van generar en el marc del projecte RECLAIM WATER. Altres dades es van obtenir d’institucions públiques i altres estudis. L’avaluació del risc per als usos considerats de l’aigua recuperada i tractada indica que aquest és baix i en alguns casos moderat, amb l’excepció de l’ús com a aigua potable, que no es preveu fer a Sabadell. Els riscs residuals que cal considerar i gestionar tenen com a protagonistes els compostos inorgànics, els compostos orgànics i la salinitat. Un altre resultat important a tenir en compte és que la recàrrega a través del llit del riu és un tractament efectiu per a reduir els riscs derivats de patògens, nutrients, compostos orgànics i partícules. Aquest resultat dóna suport a la demanda de molts autors de considerar el MAR com a un tractament més. Finalment, s’ha desenvolupat un pla de gestió del risc, integrant els resultats de l’avaluació del risc. En aquest pla no només s’han identificat els punts de control crític sinó que també s’han avaluat els dotze elements de les Guies Australianes per a la gestió del risc en MAR, fent molt més robust l’estudi. L’èmfasi ha estat posat en les accions correctives i preventives, la definició dels punts de control crític, la monitorització del sistema i els punts de mostreig.
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Kovari, Jessica. "Policies and realities of wellfield and water recharge area policy a comparison between Florida and the Netherlands /." [Gainesville, Fla.] : University of Florida, 2009. http://purl.fcla.edu/fcla/etd/UFE0041320.
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