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1.
The future availability and sustainability of fresh groundwater resources in the South West district of the national capital territory (NCT) Delhi, India, have been projected. Due to a rapid decline in groundwater level and quality, the district has been required by the Government of India to regulate development of groundwater resources. Shallow groundwater is mostly saline and water resources in the area are limited. The methodology applied here involves microzonation of the district in terms of thickness of fresh groundwater and then quantification of present and future availability of freshwater in different freshwater zones, including tentative timescales. The calculation method has been aided by data on historic trends in water level at representative groundwater monitoring stations, located either in fresh groundwater zones or near to them. It is estimated that the presently available 481 million m3 of resources will be reduced to 374 million m3 by year 2007 and to 303 million m3 by the year 2012, and by the year 2022 the district will have only 176 million m3 of available fresh groundwater resources.  相似文献   

2.
The Beijing-Tianjin-Hebei Plain (BTHP) is the political, economic and cultural center of China, where groundwater is the main source of water supply to support social and economic development. Continuous overdraft of the resources has caused a persistent decline of groundwater level and formed a huge cone of depression at a regional scale. This paper addresses current groundwater situation over the BTHP area. The paper also delineates the groundwater flow field, using groundwater level data, in order to provide an effective method for the restoration of groundwater level and associated water resources management. Based on the analysis of multiple factors, such as groundwater level, soil salinization, ground subsidence, groundwater recharge and storage, urban underground space security, formation of fractures, and seawater intrusion, the threshold for groundwater level restoration is defined, and some measures for groundwater over-exploitation management are accordingly proposed. The study shows that: (i) Since the 1980s to 2020, shallow groundwater level in the western part of the BTHP area has dropped by 25 m to 60 m, while the cumulative decline of deep groundwater in the central and eastern regions is in the range of 40–80 m; (ii) The water table of the shallow groundwater within the depression zone over the Western Piedmont Plain should be controlled in the range of 15–30 m below ground level (mbgl), while the depth of groundwater level in large and medium-sized urban areas should be controlled within 20–30 mbgl. The groundwater level in the resource preservation area should be controlled within 10–15 mbgl, and the groundwater level in the area with identified soil salinization in the central and eastern plain should be controlled within 3–10 mbgl. However, for the deep groundwater in the central and eastern plainwater, the main focus of the resources management is to control the land subsidence. The water level in the severe land subsidence area should be controlled within 45–60 mbgl, and in the general subsidence area should be controlled within 30–45 mbgl; (iii) Based on the water level recovery threshold and proposed groundwater overdraft management program, if the balance of abstraction and recharge is reached in 2025, the shallow groundwater abstraction needs to be gradually reduced by about 2×108 m3. Meanwhile, the ecological water replenishment of rivers through the South-to-North Water Transfer Project should be increased to 28.58×108 m3/a, and the deep groundwater abstraction needs to be gradually reduced by 2.24×108 m3. To reach the target of shallow groundwater level in 2040, surface water replacement is recommended with a rate of 25.77×108 m3/a and the ecological water replenishment of rivers in the South-to-North Water Diversion Project should reach 33.51×108 m3/a. For deep groundwater recovery, it is recommended to replace the deep freshwater extraction with the utilization of shallow salt water by 2.82×108 m3 , in addition to the amount of 7.86×108 m3 by water diversion. The results are of great significance to the remediation of groundwater over-exploitation, the regulation of water resources development and utilization, and ecological protection in Beijing-Tianjin-Hebei plain.  相似文献   

3.
邢台市地下水水位下降严重原因分析及对策研究   总被引：1，自引：0，他引：1  
邢台市地下水水位持续下降,针对现状,从地表水资源状况、地下水资源的构成和邢台市的供用水状况进行分析找原因,并对由于地下水水位下降,引发的各种问题进行了描述,提出了建立节水型社会、优化水资源配置、防止水质污染和开发涵养水源等措施遏制地下水水位持续下降,为邢台市合理开发利用、保护和管理地下水资源提供科学依据。  相似文献   

4.
陶虹  丁佳 《地质论评》2014,60(1):231-235
关中城市群地下水自集中开采以来区域地下水位呈整体下降趋势,主要城市集中供水水源地水位降幅30~50 m,最大超过120 m。长期过量开采地下水引起了地下水位持续下降、地面沉降、地裂缝以及水质污染等环境地质问题。近年随着城市群限制开采量,地下水水位下降及其相关环境地质问题在局部地段有所缓和。本文以50年地下水动态监测数据为基础,针对关中城市群地下水动态特征及相关的环境地质问题进行研究分析,并对预防和缓解环境地质问题、合理开发地下水资源提出建议。  相似文献   

5.
Improper design, faulty planning, mismanagement and incorrect operation of irrigation schemes are the principle reasons for the deterioration of groundwater quality in a large number of countries, in particular in semi-arid and arid regions. The aim of this study is to determine the dimensions of groundwater quality after surface irrigation was begun in the semi-arid Harran Plain. Physical and chemical parameters of the groundwater including pH, temperature, electrical conductivity (EC), sodium, potassium, calcium, magnesium, chloride, bicarbonate, sulphate, nitrate, nitrite, ammonium, total phosphorus, total organic carbon and turbidity were determined monthly during the 2006 water year. The quality of the groundwater in the study area was assessed hydrochemically in order to determine its suitability for human consumption and agricultural purposes. In the general plain, the EC values measured were considerably above the guide level of 650 μS/cm, while nitrate in particular was found in almost all groundwater samples to be significantly above the maximum admissible concentration of 50 mg/l for the quality of water intended for human consumption as per the international and national standards. Total hardness reveals that a majority of the groundwater samples fall in the very hard water category. Interpretation of analytical data shows that Ca–HCO3 and Ca–SO4 are the dominant hydrochemical facies in the study area.  相似文献   

6.
A national groundwater-monitoring network consisting of 320 stations has been operated by the Ministry of Construction and Transportation and the Korea Water Resources Corporation since 1995. The network was established as a result of the Groundwater Act of Korea, and a supplementary local groundwater monitoring network containing 10,000 stations will be established throughout the country by the year 2011. A method of allocating stations and organizing the local monitoring network has been developed, based on the analytic hierarchy process (AHP), using pairwise comparison. Several evaluation criteria were selected for determining the required number of the monitoring stations at specific local districts. Weights of the selected criteria were assigned by the pairwise comparison, reflecting hydrogeological conditions and supported by pertinent questions to 93 groundwater experts. To evaluate appropriateness of this method, an example city, Jeonju, was selected where groundwater levels were monitored; seven stations were determined as to be required for the supplementary groundwater-monitoring network. The study demonstrated the usefulness of the AHP. The concepts of the development and the structure of the AHP model can be applied to site or well selections within a particular district.  相似文献   

7.
沧州市封停深层地下水井效果及水位回升机制分析   总被引：2，自引：0，他引：2  
孙淑珍 《地下水》2011,(1):16-17,164
以沧州市2005年以来封停自备井前后深层地下水水位下降、回升数据为基础,通过对深层地下水补给与释水机制及其开采过程中激发释水效应的剖析,揭示深层地下水自然释水和开采条件下释水的规律,研究本区域深层地下水水位变化原因,为深层地下水保护和修复提出措施.  相似文献   

8.
Groundwater is an important part of the global hydrological cycle. Sustainable utilization of groundwater is related to regional ecological security and food security, especially in arid and semi-arid environments. This paper reviewed the important achievements of the research on groundwater sustainability in arid and semi-arid environments during the past 30 years, and summarized the research progress in groundwater sustainability of arid and semi-arid environments from the conception evolution of groundwater sustainability, evaluation methods, influencing factors, sustainable management, and research frontiers. Our analysis suggests that groundwater in water limited environments around the world has shown unsustainable characteristics both in terms of quantity and quality. However, the existing research focuses more on the quantitative characteristics than the quality characteristics of groundwater, and thus the seriousness of the decline in groundwater sustainability is potentially underestimated. It is pointed out that more research efforts need to be done in the future in balancing the groundwater resources for human and nature, clarifying the impacts of human disturbance and climate change on groundwater sustainability, and strengthening groundwater sustainability through transboundary watershed management. We argued that the difficulty remains how to quantify the sustainable yield of a groundwater basin, and how to assess the groundwater sustainability. Further investigations are required in improving the theoretical framework of groundwater sustainability, modeling the impacts of the various alternative groundwater development scenarios, developing more flexible and efficient indicator frameworks for sustainability evaluation of groundwater system, and deploying more sophisticated groundwater monitoring network for real-time data acquisition. Finally, awareness should also be raised towards ground water sustainability both at the legal level and in the sphere of political action.  相似文献   

9.
A multi-methodological approach based on monitoring and spatio-temporal analysis of groundwater quality changes is proposed. The presented tools are simple, quick and cost-effective to give service to all sorts of users. The chief purpose of the monitoring network is the detection of the piezometric or potenziometric level in the aquifer. The spatial and multi-temporal analysis of usual chemical and physical data provides both an assessment of the spatial vulnerability of the aquifer to seawater intrusion, defining a salinity threshold between fresh groundwater and brackish groundwater and of the water quality trend in terms of salinity. The evaluation of the salinity trend or of salinity-correlated parameters highlights the effects of groundwater mismanagement. The multiparameter logging provides a rapid groundwater quality classification for each well. The whole approach allows evaluating the effects of current management criteria and designing more appropriate management targets. The Apulian karstic coastal aquifers have been selected as a case study (Southern Italy). Three types of aquifer zones can be distinguished: (1) areas with low vulnerability to seawater intrusion, (2) areas with high vulnerability and (3) areas with variable vulnerability in which the salt degradation largely depends on the ability to manage the well discharge. The water quality degradation caused by seawater intrusion appears to be a combined effect of an anomalous succession of drought periods observed from about 1980 onwards and increased groundwater pumping, particularly during drought periods. A management criterion based on aquifer zones is proposed.  相似文献   

10.
 The supraregional GIS-supported stochastical model, WEKU, for the determination of groundwater residence times in the upper aquifers of large groundwater provinces is presented. Using a two-dimensional analytical model of groundwater flow, groundwater residence times are determined within two extreme cases. In the first case, maximal groundwater residence times are calculated, representing the part of groundwater, that is drained by the main surface water of a groundwater catchment area. In the second case, minimal groundwater residence times for drainage into the nearest surface water are determined. Using explicit distribution functions of the input parameters, mean values as well as potential ranges of variations of the groundwater residence times are derived. The WEKU model has been used for the determination of groundwater residence times throughout Germany. The model results – mean values and deviations of the groundwater velocity and the maximal and minimal groundwater residence times in the upper aquifers – are presented by general maps and discussed in detail. It is shown that the groundwater residence times in the upper aquifer vary regionally, differentiated between less than 1 year and more than 2000 years. Using this information, the time scales can be specified, until measures to remediate polluted groundwater resources may lead to a substantial groundwater quality improvement in the different groundwater provinces of Germany. With respect to its supraregional scale of application, the WEKU model may serve as a useful tool for the supraregional groundwater management on a state, federal or international level. Received: 15 August 1995 · Accepted: 15 October 1995  相似文献   

11.
辽河三角洲处于陆地和海洋的结合部,蕴含丰富的资源,具有十分重要的战略地位。项目通过三年的时间,查明了辽河三角洲地区主要含水层结构:第四系含水层系统(Q)、明化镇组含水层系统(Nm)、馆陶组含水层系统(Ng)。通过设立动态监测网,建立、完善地下水动态监测体系,实现地下水位和水质的实时监测;地下水水位动态:第四系松散岩类孔隙水较为稳定,水位动态变化不大;上新近系明化镇组和馆陶组地下水,受人类活动影响较大,由于多年连续大量开采,地下水位逐年下降,已形成了2个区域性地下水降落漏斗。地下水水质动态:第四系上更新统(Q3)浅层水Cl-、SO42-、Na+及矿化度持续升高,高矿化度水分布面积扩大,水化学类型复杂化,氯化物型和钠型水分布面积增大,向周边扩散;明化镇组和馆陶组地下水,水质优良,变化不大。针对地下水超采,注重水资源合理配置,适当减少新近系地下水资源的开采,充分利用地表水资源的对策。  相似文献   

12.
预警等级及阈值的科学确定对地下水污染风险预警系统的建立起着至关重要的作用。当前我国地下水污染风险预警相关研究尚处在探索阶段,未形成科学完备的理论与方法体系。文章基于国内外已有研究报道,较系统地梳理了地下水污染风险预警相关研究,归纳总结了预警等级及阈值确定方法的研究现状,并对进一步研究做了展望。目前阈值主要的划定方法有相关标准法、临界值法、综合评判法等。相关标准法适用于大尺度宏观区域,临界值法在基础资料较完善的研究区域具有较强的针对性和准确性,而综合评判法能够处理多个变量因素,能对定性因素做出量化评价,适用于变量、定性因素较多的研究区域,为不同条件研究区地下水污染风险预警等级划分及阈值划定方法的选择提供了理论依据。最后指出在完善我国地下水污染风险预警体系理论方法的工作中,应当进一步关注:（1）多学科研究成果的交叉渗透,借助多方法交互应用;（2）加强与地下水污染相关的水文地质调查与监测工作,不断提高地下水污染调查研究程度;（3）综合分析地质、污染源、地下水价值及动态等地下水污染影响因素,以提高预警结果科学性。  相似文献   

13.
In recent years, drought has become a global issue, especially in arid and semi-arid areas. It is without doubt that the identification and monitoring of the drought phenomenon can help to reduce the damages that would occur. In addition, rain is one of the factors which directly affect the water levels of underground water reservoirs. This research applied a linear gradient regression method developed on the basis of GRACE, CHIRPS, and data from monitoring wells to investigate the groundwater storage changes.These data have been analyzed on the Google Earth Engine platform. In order to conduct temporal and spatial analyses, the water levels of the aquifer were generated from the monitoring wells and zoned into five classes. Also, the amount of water storage and rain from the year 2003 to 2017 in the West Azerbaijan Province were investigated using the GRACE satellite and the CHIRPS data, respectively. The results obtained from the GRACE satellite data show that the average water level in the underground reservoirs in Iran had started to decrease since 2008 and reached its peak in 2016 with an average decrease of 16 cm in that year. The average annual decline of groundwater level in the studied time period was 5 cm. A chart developed from the CHIRPS annual rainfall data indicates that the biggest decline in rainfall occurred in 2008, and the declining trend has remained steady. Linear analyses were made on GRACE with CHIRPS results and monitoring wells data separately, from which the correlation coefficients are between 86% and 97%, showing generally high correlations. Furthermore, the results obtained from the zoning of the aquifer showed that in the period of 2004 to 2016, due to the decrease in rainfall and the excessive withdrawal of groundwater, the water levels also decreased.  相似文献   

14.
常州市区地下水污染研究   总被引：1，自引：0，他引：1  
根据常州市地下水环境背景值、水质长期监测数据,分析常州市地下水水质演变规律。通过分析1982年至2009年水质状况,对地下水污染程度进行分级,综合评价地下水水质。并结合地下水污染因子变化规律、水化学类型变化趋势,提出地下水保护综合治理措施。  相似文献   

15.
The Cambrian-Vendian groundwater body plays an important role in drinking water supply of capital Tallinn and other settlements in northern Estonia. Water quality in this deep-seated confined groundwater body is influenced by the intrusion of present-day seawater and pumping-induced upward migration of deeper saline groundwater. The aim of this study is to evaluate the threshold values applying the methodology worked out within the EU 6th FP project “Background criteria for the identification of groundwater thresholds (BRIDGE)” and to compare the results with the values proposed by local authorities. A database containing 250 monitoring points was completed and used for the calculation of natural background levels (as the 90 and 97.7 percentile) in groundwater. The calculation of threshold values is based on natural background levels and reference values. In case of Cambrian-Vendian groundwater body the receptor is drinking water, thus limit values set by Estonian drinking water standard were used as reference values. The threshold values proposed by local authorities are more or less the same as calculated by BRIDGE methodology. Exceptionally different values are derived in case of chloride and ammonium.  相似文献   

16.
Land subsidence in Bangkok, Thailand   总被引：9，自引：0，他引：9  
Land subsidence from deep well pumping has been affecting Bangkok for the past 35 years. Its impact is particularly critical because of the flat low-lying topography and the presence of a thick soft clay layer at the ground surface that augment flood risk and foundation engineering problems, respectively. The subsidence reached its most critical state in the early 1980s when it occurred at a rate as high as 120 mm/year. The rate decreased in the subsequent period but the subsidence-affected area expanded following the growth of the city. Despite various attempts implemented to remedy the crisis, groundwater pumping from the thick aquifer system underneath the city continued to increase from 1.2 million m3/day in the early 1980s to more than 2.0 million m3/day at the turn of the century. Piezometric levels in the main aquifer layers had been drawn down by as much as 65 m. Monitoring data showed a clear correlation between the subsidence and piezometric drawdown. The data suggested that for 1 m3 of groundwater pumped out in Bangkok Plain, approximately 0.10 m3 of ground loss occurred at the surface. Significant development has been made in numerical methods for prediction of differential settlements between building foundations caused by the piezometric drawdown in the aquifers. The strict mitigation measures adopted recently, comprising a pricing policy for groundwater management, an expansion of tap water supply, and strict enforcement of groundwater laws, have resulted in a marked drop in groundwater use. However, the land subsidence will continue for a long while owing to the time-dependent consolidation behavior of the soft clay layer and clay aquitards.  相似文献   

17.
Groundwater accounts for about half of the water use for irrigation in India.The fluctuation pattern of the groundwater level is examined by observing rainfall replenishment and monitoring wells.The southern part of Rajasthan has experienced abrupt changes in rainfall and has been highly dependent on groundwater over decades.This study presents the impact of over-dependence on groundwater usage for irrigation and other purposes,spatially and temporally.Hence,the objective of this study is to examine the groundwater level trend by using statistical analysis and geospatial technique.Rainfall factor was also studied in groundwater level fluctuation during 2009-2019.To analyze the influence of each well during recharge or withdrawal of groundwater,thiessien polygonswere generated from them.In the Jakham River basin,75 wells have been identified for water level trend study using the Mann-Kendall statistical test.The statistics of trend analysis show that 15%wells are experiencing water level decline in pre-monsoon,while very low percentage of wells have such trend during post-monsoon season.The average rate of water level decline is 0.245 m/a in pre-monsoon and 0.05 m/a in post-monsoon.The aquifer recharge potential is also decreasing by year.it is expected that such type of studies will help the policy makers to adopt advanced management practices to ensure sustainable groundwater resource management.  相似文献   

18.
Seawater intrusion is a problem in the coastal areas of Korea. Most productive agricultural fields are in the western and southern coastal areas of the country where irrigation predominantly relies on groundwater. Seawater intrusion has affected agricultural productivity. To evaluate progressive encroachment of saline water, the Korean government established a seawater intrusion monitoring well network, especially in the western and southern part of the peninsula. Automatic water levels and EC monitoring and periodic chemical analysis of groundwater help track salinization. Salinization of fresh groundwater is highly associated with groundwater withdrawal. A large proportion of the groundwaters are classified as Na–Cl and Ca–Cl types. The Na–Cl types represent effects of seawater intrusion. The highest EC level was over 1.6 km inland and high Cl values were observed up to 1.2 km inland. Lower ratios of Na/Cl and SO4/Cl than seawater values indicate the seawater encroachment. A linear relation between Na and Cl represents simple mixing of the fresh groundwater with the seawater. The saline Na–Cl typed groundwaters showed Br/Cl ratios similar to or less than seawater values. The Ca–HCO3 type groundwaters had the highest Br/Cl ratios. Substantial proportions of the groundwaters showed potential for salinity and should be better managed for sustainable agriculture.  相似文献   

19.
工程措施影响滑坡地下水动态的数值模拟研究   总被引：9，自引：2，他引：7  
大多数滑坡的发生与地下水活动有关 ,地下水的动态变化直接关系到滑坡的稳定性状况。因此 ,在滑坡治理工程中 ,首先需要研究各种影响因素和工程治理措施对坡体地下水位的影响方式 ,从而正确分析滑坡成因机制和制定合理的滑坡治理方案。基于工程滑坡实例研究 ,利用数值模拟 ,揭示了滑坡治理工程中地下排水洞的排水效果 ,分析了地表水集中入渗和设置抗滑桩后地下水渗流场的变化特征。表明数值模拟研究 ,可以有效地揭示工程措施及主要影响因素对滑坡地下水动态的影响方式 ,为滑坡治理奠定必要的基础  相似文献   

20.
Large abstraction by water-wells has been causing a linear to exponential drop in groundwater level and substantial aquifer dewatering in Dhaka, Bangladesh. The city is almost entirely dependent on groundwater, which occurs beneath the area in an unconsolidated Plio-Pleistocene sandy aquifer. Analysis shows that the pattern of water-level change largely replicates the patterns of change in the rate of groundwater abstraction. Contribution of the aquifer storage to the abstraction is estimated to be more than 15% in the year 2002. This abstraction has caused a sharp drop in water level throughout the city and turned into two cones of depression in the water level. Upper parts of the aquifer are already dewatered throughout the area, with the exception of part of the northeast and southeast corner of the city. It is calculated that about 41 million cubic metres (MCM) of the aquifer dewatered by the year 1988, which increased to 2,272 MCM in the year 2002. Water-level decline may increase non-linearly due to limiting vertical recharge in areas where the aquifer is dewatered and may severely threaten the sustainability of the aquifer.  相似文献   

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