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1.
Gyoo‐Bum Kim 《水文研究》2010,24(24):3535-3546
A number of groundwater wells for agricultural activity, including rice farming and greenhouses, have been developed near streams over the past 20 years in South Korea. The result of a stream depletion calculation using an analytical solution of complimentary error function shows that groundwater pumping at 1949 wells drilled in the Gapcheon watershed can produce stream depletion. This amount is estimated at about 7% of annual baseflow and reaches as high as 18% of monthly baseflow during the maximum agricultural water consumption period in May. Agricultural wells have a larger effect on stream depletion than domestic wells because of their higher pumping rate. Stream depletion from agricultural wells located within 200 m from a stream represents 65% of the total depletion rate. Agricultural water policy for water use at nearby streams should be changed to reduce stream depletion and thereby maintain sustainable water development in South Korea. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
2.
Bredehoeft J 《Ground water》2011,49(4):468-475
An aquifer, in a stream/aquifer system, acts as a storage reservoir for groundwater. Groundwater pumping creates stream depletion that recharges the aquifer. As wells in the aquifer are moved away from the stream, the aquifer acts to filter out annual fluctuations in pumping; with distance the stream depletion tends to become equal to the total pumping averaged as an annual rate, with only a small fluctuation. This is true for both a single well and an ensemble of wells. A typical growing season in much of the western United States is 3 to 4 months. An ensemble of irrigation wells spread more or less uniformly across an aquifer several miles wide, pumping during the growing season, will deplete the stream by approximately one-third of the total amount of water pumped during the growing season. The remaining two-thirds of stream depletion occurs outside the growing season. Furthermore, it takes more than a decade of pumping for an ensemble of wells to reach a steady-state condition in which the impact on the stream is the same in succeeding years. After a decade or more of pumping, the depletion is nearly constant through the year, with only a small seasonal fluctuation: ±10%. Conversely, stream depletion following shutting down the pumping from an ensemble of wells takes more than a decade to fully recover from the prior pumping. Effectively managing a conjunctive groundwater and surface water system requires integrating the entire system into a single management institution with a long-term outlook. 相似文献
3.
This study presents analytical solutions of the three‐dimensional groundwater flow to a well in leaky confined and leaky water table wedge‐shaped aquifers. Leaky wedge‐shaped aquifers with and without storage in the aquitard are considered, and both transient and steady‐state drawdown solutions are derived. Unlike the previous solutions of the wedge‐shaped aquifers, the leakages from aquitard are considered in these solutions and unlike similar previous work for leaky aquifers, leakage from aquitards and from the water table are treated as the lower and upper boundary conditions. A special form of finite Fourier transforms is used to transform the z‐coordinate in deriving the solutions. The leakage induced by a partially penetrating pumping well in a wedge‐shaped aquifer depends on aquitard hydraulic parameters, the wedge‐shaped aquifer parameters, as well as the pumping well parameters. We calculate lateral boundary dimensionless flux at a representative line and investigate its sensitivity to the aquitard hydraulic parameters. We also investigate the effects of wedge angle, partial penetration, screen location and piezometer location on the steady‐state dimensionless drawdown for different leakage parameters. Results of our study are presented in the form of dimensionless flux‐dimensionless time and dimensionless drawdown‐leakage parameter type curves. The results are useful for evaluating the relative role of lateral wedge boundaries and leakage source on flow in wedge‐shaped aquifers. This is very useful for water management problems and for assessing groundwater pollution. The presented analytical solutions can also be used in parameter identification and in calculating stream depletion rate and volume. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
4.
Groundwater pumping from aquifers in hydraulic connection with nearby streams has the potential to cause adverse impacts by decreasing flows to levels below those necessary to maintain aquatic ecosystems. The recent passage of the Great Lakes‐St. Lawrence River Basin Water Resources Compact has brought attention to this issue in the Great Lakes region. In particular, the legislation requires the Great Lakes states to enact measures for limiting water withdrawals that can cause adverse ecosystem impacts. This study explores how both hydrogeologic and environmental flow limitations may constrain groundwater availability in the Great Lakes Basin. A methodology for calculating maximum allowable pumping rates is presented. Groundwater availability across the basin may be constrained by a combination of hydrogeologic yield and environmental flow limitations varying over both local and regional scales. The results are sensitive to factors such as pumping time, regional and local hydrogeology, streambed conductance, and streamflow depletion limits. Understanding how these restrictions constrain groundwater usage and which hydrogeologic characteristics and spatial variables have the most influence on potential streamflow depletions has important water resources policy and management implications. 相似文献
5.
Modeling Stream-Aquifer Interactions Under Seasonal Groundwater Pumping and Managed Aquifer Recharge
In South Korea, a significant amount of groundwater is used for the heating of water-curtain insulated greenhouses during the winter dry season, which had led to problems of groundwater depletion. A managed aquifer recharge (MAR) project is currently underway with the goal of preventing such groundwater depletion in a typical cultivation area, located on an alluvial aquifer near the Nam River. In the present study, FEFLOW, a three-dimensional finite element model, was used to evaluate different strategies for MAR of the cultivation areas. A conceptual model was developed to simulate the stream-aquifer dynamics under the influence of seasonal groundwater pumping and MAR. The optimal rates and duration of MAR were assessed by analyzing the recovery of the groundwater levels and the change in the groundwater temperature. The simulation results indicate that a MAR rate of 8000 m3/d effectively restores the groundwater level when the injection wells are located inside the groundwater depletion area. It is also demonstrated that starting the MAR before the beginning of the seasonal pumping is more effective. Riverbank filtration is preferable for securing the injection water owing to plentiful source of induced recharge from the river. Locating the pumping wells adjacent to the river where there are thick permeable layers could be a good strategy for minimizing decreases in the groundwater level and temperature. 相似文献
6.
In the late 1980s, dramatic increases in water use caused over‐exploitation of groundwater resources and deterioration of water quality in Seoul metropolitan city. To monitor changes in quantity of groundwater resources and their quality, the metropolitan government established a local groundwater monitoring network in 1997 consisting of 119 monitoring wells. Groundwater resources in the urban area were affected by various human activities, including underground construction such as subways, pumping for public or private water use, leaky sewer systems and pavements. The variation patterns of the groundwater levels were mainly classified into four types, reflecting natural recharge due to rainfall events during the wet season, artificial recharge from leaky sewer or water supply systems, and heavy groundwater pumping for drainage or flood control purposes at underground construction sites. Significantly decreasing trends of groundwater levels in the suburbs of Seoul indicate groundwater use for various agricultural activities. Subway construction lowered the water level by an average of 25 m. Electrical conductivity values showed a wide range, from 100 to 1800 µS/cm (mean 470 µS/cm). Groundwater temperature generally showed a stable pattern, except for some sensitive increases at relatively shallow monitoring wells. Detailed analysis of the monitored groundwater data would provide some helpful implications for optimal and efficient management of groundwater resources in this metropolitan city. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
7.
Stream-aquifer interactions: evaluation of depletion volume and residual effects from ground water pumping 总被引：8，自引：0，他引：8
Numerical modeling techniques were used to simulate stream-aquifer interactions from seasonal ground water pumping. We used stream-aquifer models in which a shallow stream penetrates the top of an aquifer that discharges ground water to the stream as base flow. Because of the pumping, the volume of base flow discharged to the stream was reduced, and as the pumping continued, infiltration from the stream to the aquifer was induced. Both base-flow reduction and stream infiltration contributed to total stream depletion. We analyzed the depletion rates and volumes of the reduced base flow and induced stream infiltration during pumping and postpumping periods. Our results suggested that for a shallow penetrating stream with a low streambed conductance, base-flow reduction accounts for a significant percentage of the total stream depletion. Its residual effects in postpumping can last very long and may continue into the next pumping season for areas where recharge is nominal. In contrast, the contribution of the induced stream infiltration to the total stream depletion is much smaller, and its effects often become negligible shortly after pumping was stopped. For areas where surface recharge replenishes the aquifer, the residual effects of base-flow reduction and thus its depletion volume will be significantly reduced. A stream of large conductance has a high hydraulic connection to the aquifer, but the relationship between stream conductance and stream depletion is not linear. 相似文献
8.
Techniques for characterizing the hydraulic properties and groundwater flow processes of aquifers are essential to design hydrogeologic conceptual models. In this study, rapid time series temperature profiles within open‐groundwater wells in fractured rock were measured using fiber optic distributed temperature sensing (FO‐DTS). To identify zones of active groundwater flow, two continuous electrical heating cables were installed alongside a FO‐DTS cable to heat the column of water within the well and to create a temperature difference between the ambient temperature of the groundwater in the aquifer and that within the well. Additional tests were performed to examine the effects of pumping on hydraulic fracture interconnectivity around the well and to identify zones of increased groundwater flow. High‐ and low‐resolution FO‐DTS cable configurations were examined to test the sensitivities of the technique and compared with downhole video footage and geophysical logging to confirm the zones of active groundwater flow. Two examples are presented to demonstrate the usefulness of this new technique for rapid characterization of fracture zones in open boreholes. The combination of the FO‐DTS and heating cable has excellent scope as a rapid appraisal tool for borehole construction design and improving hydrogeologic conceptual models. 相似文献
9.
AbstractAn analytical solution is developed to delineate the capture zone of a pumping well in an aquifer with a regional flow perpendicular to a stream, assuming a leaky layer between the stream and the aquifer. Three different scenarios are considered for different pumping rates. At low pumping rates, the capture zone boundary will be completely contained in the aquifer. At medium pumping rates, the tip of the capture zone boundary will intrude into the leaky layer. Under these two scenarios, all the pumped water is supplied from the regional groundwater flow in the aquifer. At high pumping rates, however, the capture zone boundary intersects the stream and pumped water is supplied from both the aquifer and the stream. The two critical pumping rates which separate these three scenarios, as well as the proportion of pumped water from the stream and the aquifer, are determined for different hydraulic settings.Editor D. Koutsoyiannis; Associate editor A. KoussisCitation Asadi-Aghbolaghi, M., Rakhshandehroo, G.R., and Kompani-Zare, M., 2013. An analytical approach to capture zone delineation for a well near a stream with a leaky layer. Hydrological Sciences Journal, 58 (8), 1813–1823. 相似文献
10.
Angeliki Aisopou Philip J. Binning Hans‐Jørgen Albrechtsen Poul L. Bjerg 《Ground water》2015,53(5):722-736
This study examines the effect of pumping, hydrogeology, and pesticide characteristics on pesticide concentrations in production wells using a reactive transport model in two conceptual hydrogeologic systems; a layered aquifer with and without a stream present. The pumping rate can significantly affect the pesticide breakthrough time and maximum concentration at the well. The effect of the pumping rate on the pesticide concentration depends on the hydrogeology of the aquifer; in a layered aquifer, a high pumping rate resulted in a considerably different breakthrough than a low pumping rate, while in an aquifer with a stream the effect of the pumping rate was insignificant. Pesticide application history and properties have also a great impact on the effect of the pumping rate on the concentration at the well. The findings of the study show that variable pumping rates can generate temporal variability in the concentration at the well, which helps understanding the results of groundwater monitoring programs. The results are used to provide guidance on the design of pumping and regulatory changes for the long‐term supply of safe groundwater. The fate of selected pesticides is examined, for example, if the application of bentazone in a region with a layered aquifer stops today, the concentration at the well can continue to increase for 20 years if a low pumping rate is applied. This study concludes that because of the rapid response of the pesticide concentration at the drinking water well due to changes in pumping, wellhead management is important for managing pesticide concentrations. 相似文献
11.
Water level changes in wells provide a direct measure of the impact of groundwater development at a scale of relevance for management activities. Important information about aquifer dynamics and an aquifer's future is thus often embedded in hydrographs from continuously monitored wells. Interpretation of those hydrographs using methods developed for pumping‐test analyses can provide insights that are difficult to obtain via other means. These insights are demonstrated at two sites in the High Plains aquifer in western Kansas. One site has thin unconfined and confined intervals separated by a thick aquitard. Pumping‐induced responses in the unconfined interval indicate a closed (surrounded by units of relatively low permeability) system that is vulnerable to rapid depletion with continued development. Responses in the confined interval indicate that withdrawals are largely supported by leakage. Given the potential for rapid depletion of the unconfined interval, the probable source of that leakage, it is likely that large‐scale irrigation withdrawals will not be sustainable in the confined interval beyond a decade. A second site has a relatively thick unconfined aquifer with responses that again indicate a closed system. However, unlike the first site, previously unrecognized vertical inflow can be discerned in data from the recovery periods. In years of relatively low withdrawals, this inflow can produce year‐on‐year increases in water levels, an unexpected occurrence in western Kansas. The prevalence of bounded‐aquifer responses at both sites has important ramifications for modeling studies; transmissivity values from pumping tests, for example, must be used cautiously in regional models of such systems. 相似文献
12.
Large agricultural fields in South Korea are located mostly on alluvial plains, where a significant amount of groundwater is used for heating of water‐curtain insulated greenhouses. Such greenhouses are commonly used for crop cultivation during the winter dry season from November to March. After use the groundwater is discharged directly into streams, causing groundwater depletion. A hydrogeological study was carried out in a typical agricultural area of this type, located on an alluvial aquifer near the Nakdong River. Groundwater levels, chemical characteristics, and temperatures from 68 observation wells were analyzed to determine the impacts of seasonal groundwater pumping on the groundwater system and stream‐aquifer interactions. Our results show that the groundwater system has not yet reached a state of dynamic equilibrium. Decades of excessive seasonal pumping have caused a gradual decline of groundwater levels, leading to groundwater depletion, especially in areas further from the river. Seasonal pumping has also significantly affected groundwater quality in the aquifer near the river. Groundwater temperature is decreasing (in this case a disadvantage), and saline groundwater is being diluted by induced recharge. The results of this study provide a basic outline for effective integrated water management that is widely applicable in South Korea. 相似文献
13.
Michael N. Fienen Kenneth R. Bradbury Maribeth Kniffin Paul M. Barlow 《Ground water》2018,56(1):18-31
Groundwater models often serve as management tools to evaluate competing water uses including ecosystems, irrigated agriculture, industry, municipal supply, and others. Depletion potential mapping—showing the model‐calculated potential impacts that wells have on stream baseflow—can form the basis for multiple potential management approaches in an oversubscribed basin. Specific management approaches can include scenarios proposed by stakeholders, systematic changes in well pumping based on depletion potential, and formal constrained optimization, which can be used to quantify the tradeoff between water use and stream baseflow. Variables such as the maximum amount of reduction allowed in each well and various groupings of wells using, for example, K‐means clustering considering spatial proximity and depletion potential are considered. These approaches provide a potential starting point and guidance for resource managers and stakeholders to make decisions about groundwater management in a basin, spreading responsibility in different ways. We illustrate these approaches in the Little Plover River basin in central Wisconsin, United States—home to a rich agricultural tradition, with farmland and urban areas both in close proximity to a groundwater‐dependent trout stream. Groundwater withdrawals have reduced baseflow supplying the Little Plover River below a legally established minimum. The techniques in this work were developed in response to engaged stakeholders with various interests and goals for the basin. They sought to develop a collaborative management plan at a watershed scale that restores the flow rate in the river in a manner that incorporates principles of shared governance and results in effective and minimally disruptive changes in groundwater extraction practices. 相似文献
14.
The term capture, related to the source of water derived from wells, has been used in two distinct yet related contexts by the hydrologic community. The first is a water‐budget context, in which capture refers to decreases in the rates of groundwater outflow and (or) increases in the rates of recharge along head‐dependent boundaries of an aquifer in response to pumping. The second is a transport context, in which capture zone refers to the specific flowpaths that define the three‐dimensional, volumetric portion of a groundwater flow field that discharges to a well. A closely related issue that has become associated with the source of water to wells is streamflow depletion, which refers to the reduction in streamflow caused by pumping, and is a type of capture. Rates of capture and streamflow depletion are calculated by use of water‐budget analyses, most often with groundwater‐flow models. Transport models, particularly particle‐tracking methods, are used to determine capture zones to wells. In general, however, transport methods are not useful for quantifying actual or potential streamflow depletion or other types of capture along aquifer boundaries. To clarify the sometimes subtle differences among these terms, we describe the processes and relations among capture, capture zones, and streamflow depletion, and provide proposed terminology to distinguish among them. 相似文献
15.
Ground water pumping from aquifer systems that are hydraulically connected to streams depletes streamflow. The amplitude and timing of stream depletion depend on the stream depletion factor (SDF(i)) of the pumping wells, which is a function of aquifer hydraulic characteristics and the distance from the wells to the stream. Wells located at different locations, but having the same SDF and the same rate and schedule of pumping, will deplete streamflow equally. Wells with small SDF(i) deplete streamflow approximately synchronously with pumping. Wells with large SDF(i) deplete streamflow at approximately a constant rate throughout the year, regardless of the pumping schedule. For large values of SDF(i), artificial recharge that occurs on a different schedule from pumping can offset streamflow depletion effectively. The requirements are (1) that the pumping and recharge wells both have the same SDF(i) and (2) that the annual total quantities of recharge and pumping be equal. At larger SDF(i) values, it takes longer for pumping to impact streamflow in a wide aquifer than it does in a narrow aquifer. In basins that are closed to further withdrawals because streamflow is fully allocated, water-use changes replace new allocations as the source of water for new developments. Ground water recharge can be managed to offset the impacts of new ground water developments, allowing for changes in the timing and source of withdrawals from a basin without injuring existing users or instream flows. 相似文献
16.
Influence of Hydraulic Fracturing on Overlying Aquifers in the Presence of Leaky Abandoned Wells 
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下载免费PDF全文 The association between hydrocarbon‐rich reservoirs and organic‐rich source rocks means unconventional oil and gas plays usually occur in mature sedimentary basins—where large‐scale conventional development has already taken place. Abandoned wells in proximity to hydraulic fracturing could be affected by increased fluid pressures and corresponding newly generated fractures that directly connect (frac hit) to an abandoned well or to existing fractures intersecting an abandoned well. If contaminants migrate to a pathway hydraulically connected to an abandoned well, upward leakage may occur. Potential effects of hydraulic fracturing on upward flow through a particular type of leaky abandoned well—abandoned oil and gas wells converted into water wells were investigated using numerical modeling. Several factors that affect flow to leaky wells were considered including proximity of a leaky well to hydraulic fracturing, flowback, production, and leaky well abandonment methods. The numerical model used historical records and available industry data for the Eagle Ford Shale play in south Texas. Numerical simulations indicate that upward contaminant migration could occur through leaky converted wells if certain spatial and hydraulic conditions exist. Upward flow through leaky converted wells increased with proximity to hydraulic fracturing, but decreased when flowback and production occurred. Volumetric flow rates ranged between 0 and 0.086 m3/d for hydraulic‐fracturing scenarios. Potential groundwater impacts should be paired with plausible transport mechanisms, and upward flow through leaky abandoned wells could be unrelated to hydraulic fracturing. The results also underscore the need to evaluate historical activities. 相似文献
17.
Pumping test evaluation of stream depletion parameters 总被引：1，自引：0，他引：1
18.
Abstract. We have developed a program which aids in the design and analysis of pumping tests and slug tests. In design mode, the program emphasizes calculation and plotting of the sensitivities of drawdown (or head) to well function parameters. In analysis mode, the program can analyze a given set of experimental data. For pumping tests, the program allows multiple observation wells and multiple variable-rate pumping wells. The program is written in a modular fashion, allowing easy addition of well functions to the currently existing library. An example based on a hypothetical pumping test illustrates the utility of sensitivity analysis for well test design. 相似文献
19.
The Kuwait Group consists mainly of clastic sediments overlying unconformably the Dammam Formation of Tertiary age. The Kuwait Group is generally divided into three main hydrostratigraphic units: the upper and lower aquifers separated by an aquitard. The upper aquifer is further divided into the water table aquifer, an aquitard and a semiconfined aquifer. This semiconfined unit was pumped and the drawdowns were observed in piezometers screened in various subunits of the Kuwait Group. Some pumping tests of short duration were carried out in the top water table aquifer as well. These tests showed that the subunits of the Kuwait Group are hydraulically interconnected to a varying degree.
The pumping test data were analysed using conventional analytical solutions. The semiconfined pumping test was also simulated by a quasi-three-dimensional model using a leaky multiaquifer modelling technique. The initial hydraulic parameters were improved manually in the model till best fit drawdowns were obtained.
The final parameters obtained by simulation of the pumping tests were used in designing a pilot drainage system for the control of a rising groundwater table in parts of Kuwait City. 相似文献
20.
Narayan C. Ghosh Govinda C. Mishra Cornelius S. S. Sandhu Thomas Grischek Vikrant V. Singh 《Ground water》2015,53(5):794-805
The article presents semi‐analytical mathematical models to asses (1) enhancements of seepage from a canal and (2) induced flow from a partially penetrating river in an unconfined aquifer consequent to groundwater withdrawal in a well field in the vicinity of the river and canal. The nonlinear exponential relation between seepage from a canal reach and hydraulic head in the aquifer beneath the canal reach is used for quantifying seepage from the canal reach. Hantush's (1967) basic solution for water table rise due to recharge from a rectangular spreading basin in absence of pumping well is used for generating unit pulse response function coefficients for water table rise in the aquifer. Duhamel's convolution theory and method of superposition are applied to obtain water table position due to pumping and recharge from different canal reaches. Hunt's (1999) basic solution for river depletion due to constant pumping from a well in the vicinity of a partially penetrating river is used to generate unit pulse response function coefficients. Applying convolution technique and superposition, treating the recharge from canal reaches as recharge through conceptual injection wells, river depletion consequent to variable pumping and recharge is quantified. The integrated model is applied to a case study in Haridwar (India). The well field consists of 22 pumping wells located in the vicinity of a perennial river and a canal network. The river bank filtrate portion consequent to pumping is quantified. 相似文献