Search

The neutron activation of stable isotopes in environmental matrices, such as soil and groundwater, is a critical aspect of assessing the impact of radionuclide production facilities on the surrounding ecosystem. The envisioned Low-Energy Radioactive Ion Beams (LERIB) facility at the iThemba LABS, South Africa is anticipated to generate significant sources of ionising radiation. The study investigated the possible repercussions of neutron irradiation stemming from the facility, focusing on the activation of stable isotopic compositions in the environment. The investigation employed a combination of experimental and analytical techniques to characterize the neutron activation products in soil and groundwater samples collected from the vicinity. Samples were collected from designated areas for background radiological measurements and were irradiated with neutrons for a period of 1 h. The induced radioactivity measured by the High Purity Germanium detector included 24Na, 22Na, 54Mn, 52Mn, and 46Sc. The application of Darcy’s law for groundwater velocity suggests that radionuclides in groundwater will migrate at an average flow velocity of 0.8 m/day. The isotopes with longer half-lives have count rates at background concentrations; therefore, environmental impacts on the site and surrounding communities might be minimal. [ABSTRACT FROM AUTHOR]

Current groundwater challenges have made evident that national and international groundwater law needs a thorough revision. In this article, we explore earth system law (ESL) and rights of nature (RoN) as possible approaches to rethink groundwater law. Taking inspiration from ESL scholarship, RoN literature, Indigenous worldviews, and socio-ecological movements, we analyze law as a critical element of the human-political-social system, which creates regulatory institutions with the aim to provide a social order for humanity, an order that is being affected by deteriorating earth systems, including groundwater. Recognizing RoN and thinking law through the lenses of ESL involve a new understanding of what groundwater law could be and what the subject of the law could be. So far, little attention has been given to how these approaches can be used to redesign groundwater law, and what implications this could have on groundwater governance and sustainability. Therefore, this article explores the possibility of reforming groundwater law through the lenses of ESL and RoN. It investigates which legal mechanisms are being used to recognize RoN, and what their legal and practical implications have been so far. This article aims to contribute not only to advancing the academic debate on RoN and ESL but also to share light on different ways to reform groundwater law, which includes a new understanding of sustainability and socio-nature relations. This article is categorized under: Human Water > Rights to Water Human Water > Water Governance Science of Water > Water and Environmental Change [ABSTRACT FROM AUTHOR]

As groundwater is the primary element of life, countries all over the world are experimenting with legal reforms. The degree to which law reforms combine justice and sustainability is a crucial question. In response to this question, the present article focuses on a case study of Uttar Pradesh, India. Our response is based on a content analysis of the Uttar Pradesh Groundwater (Management and Regulation) Act, 2019, and the Uttar Pradesh Groundwater (Management and Regulation) Rules, 2020. Three conclusions emerged from our investigation. First, the 2019 Groundwater Act and the 2020 Draft Groundwater Rules are primarily motivated by concerns about resource sustainability, particularly in areas where the water table is steadily declining. Still, neither the 2019 Groundwater Act nor the 2020 Draft Groundwater Rules propose any proactive groundwater justice measures. Second, we suggest that some locally defined basic elements are critical in supporting sustainability and - to a lesser extent - groundwater justice. These characteristics include a community's ability to (1) recognize a crisis and show a willingness to address it; (2) establish a rule-bound community groundwater resource; (3) demonstrate leadership and a sense of community; and (4) make use of awareness, information, and knowledge. Our third conclusion is that there is a need for community practices and state-led groundwater law to co-evolve; this co-evolution has the potential to create groundwater arrangements that support both groundwater justice and sustainability. [ABSTRACT FROM AUTHOR]

Ren, J.; Zhuang, T.; Wang, D., and Dai, J., 2023. Water flow and heat transport in the hyporheic zone of island riparian: A field experiment and numerical simulation. Journal of Coastal Research, 39(5), 848–861. Charlotte (North Carolina), ISSN 0749-0208. Water-level fluctuation is an important factor affecting the island riparian's surface water–groundwater interaction. An island riparian section in the Yueyang section of Dongting Lake downstream of the Three Gorges Dam was selected as the research object. The dimensional transient analysis method and the numerical simulation method of temperature tracing were used to study the water exchange characteristics of the island riparian hyporheic zone. The accuracy of the flow-heat coupling model is verified by the measured data, and the influence of water-level fluctuation on the dynamic change of water and heat in the island riparian was further analyzed. Four analytical models were compared and analyzed. The results show that the dynamic change process of island riparian temperature can be accurately depicted. The vertical temperature stratification of the island riparian is obvious, and the temperature field distribution of the island riparian is affected by various factors such as water-level change, temperature change, and depth. Compared with the numerical model and the four analytical models, the vertical seepage velocity of the island riparian was calculated by the amplitude method, which conformed to the law of groundwater fluctuation and had little difference. It is found that the time period for river water to recharge the groundwater of the island riparian is much larger than the time period for the recharge of the groundwater of the island riparian; the amount of groundwater recharged by the river is larger than that of the groundwater recharge of the island riparian. [ABSTRACT FROM AUTHOR]

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Under the background of drastic global climate change, the evolution law of groundwater resources in the northeastern margin of the Tibetan Plateau presents new characteristics, and the groundwater is gradually becoming more complicated, diversified and disordered. In this study, cross-correlation analysis, wavelet analysis and cross-wavelet transform were used to explore the response mechanism and time delay effect of groundwater, exploitation amount, rainfall and surface runoff in the northeastern margin of the Tibetan Plateau. The results show that the groundwater depth increased with the increase in the exploitation amount and decreased with the increase in the rainfall-to-exploitation ration and the surface runoff-to-exploitation ratio from 1980 to 2020. On the annual scale, groundwater, rainfall and surface runoff had a strong cohesiveness period of 12a. On the monthly scale, groundwater lagged behind rainfall and surface runoff for 3 months and 2 months, respectively. The above conclusions provide a scientific theoretical basis for deepening the characteristics of groundwater endowment, the evolution law of water cycle elements and the theory of the hydrological cycle in the northeastern margin of the Tibetan Plateau. [ABSTRACT FROM AUTHOR]

The article discusses the benefits for Australia of adopting U.S. law in resolving interstate groundwater dispute resolution. It explains interstate litigation in the U.S. and the role of groundwater within it. It examines interstate disputes in Australia and the role of groundwater in the future. It explores the Australian High Court's adoption of ideas from other countries and the constitutional basis under which it can adopt U.S. Supreme Court jurisprudence in interstate water disputes.

The United States lacks any meaningful interstate groundwater regulation. Without regulation, users of groundwater will continue to deplete precious aquifers. As aquifers get further depleted, overall water security diminishes, overuse becomes more entrenched, and the adverse effects from overuse become increasingly dangerous. Climate change induced drought and the over appropriation of surface waters will intensify interstate groundwater disputes going forward. The Supreme Court recently considered one of these conflicts in Mississippi v. Tennessee. The Court held that its doctrine of equitable apportionment applied to interstate groundwater disputes. Previously, the Court had only applied equitable apportionment to interstate surface waters and border-crossing anadromous fish. The Court ultimately dismissed the case on procedural grounds, leaving open how it would equitably apportion groundwater. This Note demonstrates that the Court's surface water equitable apportionment doctrine, which primarily protects established uses, is insufficient to protect interstate groundwater resources. Protecting established uses of an overused aquifer ensures further depletion. Instead of relying on its surface water doctrine, the Court should create a new equitable apportionment doctrine for groundwater that uses proportional sustainable yield as its guiding beacon. Proportional sustainable yield allows each state to use the amount of groundwater that it contributes to the aquifer each year. In addition, Congress and federal agencies should step in to incentivize interstate groundwater compacts by offering to fund groundwater-related projects, but only after the relevant states successfully negotiate a sustainable groundwater compact. Since the problem of aquifer depletion becomes more insidious with each passing year, prompt action must be taken to bring groundwater use into balance with the rate of aquifer recharge. [ABSTRACT FROM AUTHOR]

Groundwater is an essential water source for millions of Americans, and it is invaluable for those in the western United States. It is stored in underground aquifers, geological formations of permeable rock and pore space, which lie under every state in the country. But states have no uniform standard for how they manage the withdrawal of groundwater, and even states with somewhat similar legal regimes for water use allow users to extract groundwater differently. These disparities create a resource-use environment that is ripe for conflict. An interstate groundwater dispute, however, had never been decided in the U.S. Supreme Court until November 2021. For the aquifer at issue in Mississippi v. Tennessee, the Court endorsed equitable apportionment—a legal doctrine that it had historically applied only to interstate surface water disputes—in a myopic decision. The doctrine is illsuited to emerging groundwater conflicts in the West not only because it is less feasible for a hard-to-measure resource like aquifers, but also because its emphasis on total consumption is unsustainable for the region’s arid future. The more suitable doctrine of interstate nuisance focuses on current use and works backward to determine how states can sustainably use a water resource while doing minimal harm to each other. Current and emerging conflicts in the West, including those involving the Snake Valley and Ogallala Aquifers, would benefit from the application of interstate nuisance. [ABSTRACT FROM AUTHOR]

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article addresses the decision of the U.S. Supreme Court on the case, Mississippi v. Tennessee, which marked a potential turning point for the doctrine of equitable apportionment. Topics discussed include history of equitable apportionment, use of equitable apportionment in resolving interstate water disputes, and highlights of the case.

Riverbank filtration (RBF) is increasingly being used as a relatively cheap and sustainable means to improve the quality of surface water. Due to the obvious differences in physical, chemical, and biological characteristics between river water and groundwater, there are strong and complex physical, chemical, and biogeochemical effects in the process of bank filtration. In this paper, multivariate statistical analysis was used to identify the spatial variation of hydrogeochemical groundwater in the process of bank filtration. Firstly, the evolution process of groundwater hydrochemistry during the filtration process was identified through factor analysis. According to the results, the evolution of groundwater hydrochemistry in this area is attributable to four main types of reactions: (1) Leaching; (2) Regional groundwater influence; (3) Aerobic respiration and denitrification; and (4) Mn (IV)/Fe (III)/SO42− reduction. According to the similarity of the geochemistry, the flow path could be divided into four different hydrochemical zones through cluster analysis, revealing the evolution law of groundwater hydrochemistry and its main influencing factors during riverbank infiltration. Large hydraulic gradient in The Zone Strongly Influenced by River Water (The first group) resulted in a weak effect of leaching on groundwater chemistry. Reoxygenation and microorganism respiration occurred in The Zone Moderately Influenced by River Water (The second group), The Zone Weakly Influenced by River Water (The third group), and The Zone Strongly Influenced by Regional Groundwater (The fourth group), resulting in fluctuations in Eh and pH values of groundwater. As a result, sulfate reduction and Mn (IV) and Fe (III) reduction alternated along the flow path. The Zone Strongly Influenced by Regional Groundwater (The fourth group) groundwater chemistry was mainly affected by regional groundwater. [ABSTRACT FROM AUTHOR]

To complete groundwater diversion, the complex flow law of groundwater in rocks must be investigated so that groundwater diversion can be improved. This research uses the computer finite element method (FEM), CT scanning calculation method, Avizo method, and digital core technology combined with the Fluent calculation method (FCM) to reconstruct rocks with microscopic pore structures on a computer. The numerical simulation results under different conditions show that: the total pressure change gradually decreases under different pressure gradients. In a seepage channel, the seepage path does not change with the change in seepage pressure, and the seepage velocity is the largest in the center of the pore. The longer the seepage path is, the greater the decrease in seepage velocity. Different seepage directions have similar seepage laws. The research results provide effective guidance for the project to control groundwater. [ABSTRACT FROM AUTHOR]

A set of one-dimensional experimental device for solute transport in non-penetrating fractured clay are developed, which can study the laws of groundwater flow and solute transport under different hydraulic heads, fractured aperture, and thickness of non-penetrating zones. The experimental results show that the solute will quickly reach the bottom of the clay along the non-penetrating fracture, and there is an obvious dominant flow phenomenon compared with the intact clay. According to the experimental data and numerical calculation results, the model parameters of the fracture and each soil layer were identified, and the verified numerical model was used to simulate the solute transport in the non-penetrating fractured clay. The numerical results show that the increase of the thickness for the non-penetrating zone has a significant improvement on the anti-seepage ability of clay, and the increase of the hydraulic head pressure and fractured aperture leads to a faster growth rate of the solute concentration, which indicates that the solute breaks down the lower impermeable clay layer under high head pressure. The research results are of great significance for the bottom anti-seepage layer similar to landfill projects. [ABSTRACT FROM AUTHOR]

Despite now widespread scholarly scientific acknowledgement of the ecological importance of groundwater, progress on protecting groundwater-dependent ecosystems (GDEs) in practice has been slow. Extending the legal concept of environmental water rights from the surface water context to groundwater may help to accelerate protections and to promote adaptive water governance, particularly when combined with regulatory rules. Although some groundwater law frameworks have developed regulatory rules to protect GDEs that mirror those for surface water, they have yet to develop frameworks to support environmental groundwater rights that mirror environmental surface water rights, i.e., in-ground flow rights equivalent to in-stream flow rights. These rights are generally quantified, transferable, allow in situ use or withdrawal, and are held and enforced by an identified public or private entity. Here, I first conceptualize environmental groundwater rights and then evaluate the conceptual and practical advantages and challenges for adaptive water governance of a legal framework to support them, in a way that is intended to be relevant to diverse jurisdictional contexts. To do so, I use two existing theoretical frameworks: one for evaluating alternative approaches to providing environmental water, and the second for considering the roles of law in adaptive water governance. I find that water markets and some environmental crises may present windows of opportunity for establishing environmental groundwater rights and, thereby, local-scale thresholds of minimum protection. These rights may circumvent barriers to adaptive governance that often characterize water law. They may also facilitate adaptive governance by allowing learning, revision, flexibility, and experimentation about the environmental water requirements of GDEs to fill critical knowledge gaps. A legal framework for environmental groundwater rights can also harness and legitimize local environmental and Indigenous voices and increase access to resources. When combined with larger scale regulatory rules, such a legal framework can also help to facilitate multiscalar governance. [ABSTRACT FROM AUTHOR]

The North Indian states of Punjab and Haryana (P&H) are a part of the water-rich Indo-Gangetic river basin. Despite this abundance, both states are on the cusp of a severe water crisis due to groundwater over-extraction. The proliferation of tubewells to support irrigation is responsible for more than 90 per cent of the groundwater extraction in both states. What started as a boon during the Green Revolution has given rise to a host of socio-economic and environmental issues. Overexploitation of groundwater is not a simple problem that the laws can quickly fix. In 2020, both P&H passed legislation to manage their water, including groundwater; however, these legal responses are far from what is required. This article examines the law on groundwater in P&H, focusing on the fallouts of silo-based decision-making where the different facets of water management are left to various authorities resulting in working at cross-purposes and inefficient decision-making. We argue that there is an urgent need to (1) delink groundwater rights from land rights and (2) adopt an integrated resource management strategy if P&H are to utilise their groundwater sustainably. [ABSTRACT FROM AUTHOR]

Freezing and thawing can cause dynamic fluctuations of the groundwater level, resulting in the migration and retention of LNAPLs. However, this process is difficult to observe visually, and a suitable simulation method for its quantitative calculation is lacking. In this study, a numerical simulation is established by coupling the HYDRUS-1D software and the TOUGH program to realize dynamic simulation of the entire process of soil temperature changes, water migration, water level fluctuation, and redistribution of LNAPLs during the freeze–thaw process. The results of the study show that the process of soil freezing and thawing causes water migration, which in turn causes groundwater level fluctuation, leading to the migration and redistribution of LNAPLs within the water level fluctuation zone. In this process, the soil particle size and porosity control the response degree and speed of the water level under freezing and thawing and the spatiotemporal distribution of LNAPLs by affecting the soil temperature, capillary force, and water migration. The migration ability of free LNAPLs is determined by their own density and viscosity; the retention of residual LNAPLs is affected by soil porosity and permeability as well as LNAPL viscosity. The results of this study can not only be used to develop a simulation method for the migration and retention mechanism of LNAPLs in cold regions but also serve as a scientific and theoretical basis for LNAPL pollution control in seasonal frozen soil regions. [ABSTRACT FROM AUTHOR]

Copyright of Hydrogeology & Engineering Geology / Shuiwendizhi Gongchengdizhi is the property of Hydrogeology & Engineering Geology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article focuses on Arthur Maass, professor of Government at Harvard University who was particularly interested in the comparative study of irrigation systems and wrote an important book presenting his conclusions. Topics include examines the objects of comparison were three irrigation systems in the western United States and three in Eastern Spain such as Valencia, Alicante and Murcia.

Water is considered the lifeline of our ecological existence. It not only plays an important role in the socioeconomic conditions of the state but also in the well-being of an individual. Water, which is available in many forms like surface water, groundwater, ice caps, etc., needs proper regulation and management. The groundwater, once seen as a private resource, is now considered a public resource to which the state is trustee. Groundwater management has been a burning issue worldwide, for which states have been taking vibrant steps. At the national level, some guidelines in the form of Model Bills have been framed, but the matter, as per the constitutional setup, is the domain of states. The erstwhile state of Jammu and Kashmir has taken a dynamic step to regulate water resources by enacting the Jammu and Kashmir Water Resources (Regulation and Management) Act, 2010. This paper focuses on the importance of groundwater and its management. It also underlines the private and public rights with regard to sub-surface water. Finally, it concludes with some valuable suggestions which may be taken into consideration for proper regulation and management of groundwater in the union territory of Jammu and Kashmir. [ABSTRACT FROM AUTHOR]

The article discusses the implications of the Supreme Court's 2020 Hawaii Wildlife Fund v. County of Maui decision and its impact on groundwater regulation through the Clean Water Act. It mentions argues the U.S. Environmental Protection Agency (EPA) needs to draft more specific guidance to determine when discharges to navigable waters through groundwater should require permits.

The article examines the possible effects of the expansion of federal water jurisdiction in the decision by the U.S. Supreme Court in the case County of Maui v. Hawai'i Wildlife Fund in April 2020. Other topics include the requirements under the National Pollutant Discharge Elimination System (NPDES) permit, the Clean Water Act (CWA) law, and the proposed CWA amendments to address issues on groundwater and surface water integration.

Since the late 1990s, the changing of groundwater level in the aquifer beneath Bangkok has been realized because the enforcement of groundwater laws and improvement of water supply have been adopted. Then, the groundwater with piezometric drawdown has risen to almost hydrostatic equilibrium. In the principle of soil mechanics, when the porewater pressure in soil mass increases, the effective stress decreases. This can affect underground structures. Under the soft ground condition such as Bangkok, Thailand, pile foundations are commonly constructed to support structures. With decreased effective stresses, the loss of ultimate load-carrying capacity of existing piles can occur, and the structures can be damaged. This research investigates the effects of the groundwater rising on the pile foundation in the Bangkok subsoil. An advanced numerical model with the fully coupled flow deformation analysis, both groundwater flow and soil deformation behaviors with time-dependent conditions are modeled, is conducted by using PLAXIS 2D. The results found that the calculation type of fully coupled flow deformation can express the pile-soil movement behavior. The pile-soil heave and the pile load capacity be significantly reduced during the groundwater rising event. Despite the reduction of pile load capacity with groundwater changed not enough to failure (Factor of safety <1.0), the pile stability should be concerned, and the optimum groundwater level must be controlled [ABSTRACT FROM AUTHOR]

Quarrels between states sharing a transboundary aquifer (TBA) have been relatively minor in comparison with the more boisterous disputes seen in many of the world's shared river basins. Yet, transboundary groundwater can easily serve as the basis for cross-border disagreements. Twice as many TBAs and shared groundwater bodies have been identified globally as compared to transboundary rivers and lakes, and the volume of accessible groundwater exceeds all surface waters by a factor of one hundred. Yet, the number of treaties in force for TBAs is miniscule in comparison with those for transboundary rivers and lakes. Moreover, dozens of nations exploit groundwater from a TBA, often unilaterally and without knowing the cross-border implications, or even that the aquifer is transboundary. The lack of prioritization of groundwater in international practice and law, coupled with the reality that groundwater is "out of sight," and thereby "out of mind," has relegated shared aquifers as the neglected stepchildren of international water law. But, with many of the world's nations experiencing growing water scarcity and stress, this situation undoubtedly will change. This essay highlights the growing pains of international groundwater law and the challenges for its identification and articulation. Specific hydrogeologic characteristics of various TBAs are presented and, where relevant, placed in the context of water scarcity and security and recognized international legal norms. [ABSTRACT FROM AUTHOR]

South Africa is a semi-arid country that increasingly relies on groundwater as a freshwater source for both socio-economic and environmental systems. Groundwater resources are, however, limited and fragile due to factors such as climate change, exploitation and pollution. This renders the groundwater regulatory framework essential. Yet in South Africa, groundwater governance is not strongly emphasised in the novel regulatory framework instated by the National Water Act 38 of 1998 (the NWA). Naturally, uncertainties and challenges arise as to, inter alia, the appropriate allocation and effective protection of the country's groundwater resources. This paper traces established groundwater governance practices and critically reflects on how the concept of public trusteeship, as introduced by the NWA, changes and informs the country's groundwater governance practices. [ABSTRACT FROM AUTHOR]

The article focuses on the decision of the U.S. Supreme Court in the case related to environmental law. The case discussed include County of Maui v. Hawai'i Wildlife Fund on Clean Water Act jurisdiction over groundwater discharges requires a National Pollutant Discharge Elimination System (NPDES) permit and Atlantic Richfield Company v. Gregory A. Christian, et al. on Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) and the Environmental Protection Agency (EPA).

The article discusses the components of a Sustainable Groundwater Management Act (SGMA) Groundwater Plans to make sure groundwater extraction has no adverse effects to fisheries in California. Also cited are the importance of groundwater in surface water supply to support fisheries like trout and salmon, the effect of groundwater location on groundwater pumping on fisheries, and the state's public trust law covering surface water flows.

Groundwater resources have come under increasing pressure from overuse and pollution leading to declines in both quantity and quality. As a renewable resource, the continued availability of sufficient and clean groundwater depends on its sustainable use. However, groundwater use has often been unsustainable, and in many countries—both developing and developed—legal and policy frameworks for its sustainable use remain limited and their design and implementation are under-researched. This article examines the drivers that motivate the development and implementation of legal and policy frameworks capable of ensuring the long-term sustainability of groundwater resources. Case studies conducted in Australia and Costa Rica reveal four key drivers: (i) the existence of a water crisis, (ii) awareness—which leads to information, learning and monitoring, (iii) civic leadership to foster meaningful participation and, (iv) government research and funding in order to understand the complexity of groundwater. [ABSTRACT FROM AUTHOR]

Solute transport characteristics and groundwater connection structures are mainly studied in this paper by adopting the numerical simulation and field tracer test. Firstly, the simulation method of solute transport is proposed. Then two kinds of representative geological models of tracer test are built, and the process of solute transport is simulated. The variation characteristics of solute transport under the conditions of straight pipeline and branch pipeline are summarized by analysis of the simulation results. The effects of the pipeline width, flow velocity and path difference of branch pipelines on the tracer curve are discussed. General laws of groundwater connection tracer curve are obtained. Finally, based on the field test results, and combined with engineering geological conditions, characteristics of karst groundwater systems, the groundwater connection structures are analysed and speculated in detail by the flow velocity and local monitoring curve. The results show that: (i) As the flow velocity increases, the peak of the tracer curve decreases gradually, as well as the time to peak; (ii) The peak of the tracer curve gradually decreases with the increasing pipeline width; (iii) Under the different path difference of branch pipeline, the tracer curves all present obvious 'trailing' phenomenon; (iv) The analysis process of groundwater connection structures can provide references for the same type of hydrological geological problems. [ABSTRACT FROM AUTHOR]

The article focuses on general approach to the management of groundwater in the U.S. Topics discussed include limiting use to maintain minimum stream flows or other policies; local groundwater management of aquifers; and the enactment of Endangered Species Act for governing the conservation of endangered species.

The article examines the conduit theory of the U.S. Clean Water Act (CWA) jurisdiction in 2019 over the issue of tributary groundwater pollution. Topics discussed include the passage of the CWA in 1972, the scope of the terms navigable waters and the waters of the U.S., and the adoption by the courts of the conduit theory.

Examines the policies and practices of the High Plains Underground Water Conservation District of Texas. Establishment of the district in 1951; Demand management; Ownership of groundwater by the landowner; Well-spacing requirements; Restrictions on groundwater withdrawals; Water table in the district since 1963.

The Groundwater (Sustainable Management) Bill, 2017 drafted by the Ministry of Water Resources, River Development & Ganga Rejuvenation provides a new template that states can use to adopt legislation capable of addressing the fast-increasing groundwater crisis faced by many states. This Bill follows on an earlier model bill drafted in 1970 and updated several times until 2005 on which the dozen of existing groundwater acts are based. This 1970 template is unsuited to the present needs of a country where groundwater is now the primary source of drinking water and irrigation. In particular, it fails to provide for local-level regulation of what is often known as the most local source of water and fails to provide for conservation measures at aquifer level. The 2017 Bill integrates legal developments having taking place since the 1970s, such as the decentralization reforms kick-started in the 1990s, the recognition of water as a fundamental right and its recognition as a public trust. In doing so, it provides new bases for regulating groundwater as a public resource and to take measures at aquifer level, something that is crucial to address ongoing overexploitation and falling water tables. [ABSTRACT FROM AUTHOR]

In 2017, the United States Court of Appeals for the Ninth Circuit ruled in favor of the Agua Caliente Tribe of Cahuilla Indians in a suit brought by the Tribe against two California state water agencies. In a monumental decision, the Ninth Circuit held that the Tribe had reserved rights to the groundwater underlying its reservation under the Winters doctrine, a century-old legal doctrine which governs reserved water rights on federal reservations of land. Although the core principles of the Winters doctrine are longstanding, many questions concerning the scope of the doctrine have remained unresolved. The holding of Agua Caliente is thus a historic decision, representing the only federal appellate authority explicitly extending the Winters doctrine to groundwater. Agua Caliente is a significant victory for tribal water rights and can even be called groundbreaking. However, this Chapter argues that the Ninth Circuit's ruling was not at all unprecedented. After examining the controlling case law, this Chapter concludes that the Ninth Circuit reached the correct result, as the holding in Agua Caliente aligns with Winters and its progeny. As the Supreme Court did in the Winters case that established the reserved rights doctrine, the Ninth Circuit in Agua Caliente has adhered to an enduring rule of fairness intended to give meaningful effect to the rights of Indians. [ABSTRACT FROM AUTHOR]

It is an efficient way of dynamic characteristics and driving factors analyses of groundwater system to make clear of groundwater cycle and its influence degree by anthropogenic activities. First of all, the temporal and spatial variation law of groundwater level was analyzed based on the measured data of groundwater level in People’s Victory Canal Irrigation District in 1993–2013; then, the influence degree of each influencing factor on the groundwater level was quantified by using correlation analysis; finally, the dominant driving factors influencing the evolution of groundwater level were determined using grey relational analysis. The results show that the groundwater level decreased with the decrease of precipitation, and decreased with the decrease of irrigation water from the Canal, and decreased with the increase of groundwater exploitation. Human activities played a dominant role in the variation of groundwater, and the irrigation water of wells as well as the mining of groundwater for living and industrial use was the dominant driving factors of the variation of groundwater level in the study area. [ABSTRACT FROM AUTHOR]