Search Results (16)

Kern County is one of the most valuable agricultural counties in the nation. This, however, is being put in jeopardy with the recently implemented Sustainable Groundwater Management Act (SGMA) in response to the ongoing California drought and extensive groundwater pumping for irrigation. The Groundwater Sustainability Agencies (GSAs) are responsible for developing Groundwater Sustainability Plans to address the new SGMA policies. The objective of this paper is to examine the Kern Groundwater Sustainability Plan (KGSP), determine its strengths and weaknesses, and provide recommendations for the updated plan released in 2025. The plan performs well in defining criteria that must be met, but fails to address how these goals will be implemented. Based on our policy analysis, our recommendations include standardizing groundwater management terms across sub-basins, defining clear measurements of undesirable results, utilizing financial (dis)incentives to encourage groundwater users to manage water sustainably, and increasing interconnections between local and state organizations. Importantly, improving this policy process for the SGMA may be an example for critically overdrafted groundwater basins globally on how to more sustainably manage their groundwater. Full article

The Central Valley of California is one of the most prolific agricultural regions in the world. Agriculture is reliant on the conjunctive use of surface-water and groundwater. The lack of available surface-water and land-use changes have led to pumping-induced groundwater-level and storage declines, land subsidence, changes to streamflow and the environment, and the degradation of water quality. As a result, in part, the Sustainable Groundwater Management Act (SGMA) was developed. An examination of the components of SGMA and contextualizing regional model applications within the SGMA framework was undertaken to better understand and quantify many of the components of SGMA. Specifically, the U.S. Geological Survey (USGS) updated the Central Valley Hydrologic Model (CVHM) to assess hydrologic system responses to climatic variation, surface-water availability, land-use changes, and groundwater pumping. MODFLOW-OWHM has been enhanced to simulate the timing of land subsidence and attribute its inelastic and elastic portions. In addition to extending CVHM through 2019, the new version, CVHM2, includes several enhancements as follows: managed aquifer recharge (MAR), pumping with multi-aquifer wells, inflows from ungauged watersheds, and more detailed water-balance subregions, streamflow network, diversions, tile drains, land use, aquifer properties, and groundwater level and land subsidence observations. Combined with historical approximations, CVHM2 estimates approximately 158 km³ of storage loss in the Central Valley from pre-development to 2019. About 15% of the total storage loss is permanent loss of storage from subsidence that has caused damage to infrastructure. Climate extremes will likely complicate the efforts of water managers to store more water in the ground. CVHM2 can provide data in the form of aggregated input datasets, simulate climatic variations and changes, land-use changes or water management scenarios, and resulting changes in groundwater levels, storage, and land subsidence to assist decision-makers in the conjunctive management of water supplies. Full article

The Punjab Preservation of Subsoil Water Act 2009 is a legislative measure introduced to address the critical issue of groundwater depletion in Punjab, India. This research examines the implications of this Act and the rising groundwater scarcity in Punjab. Using qualitative research methods, including GIS mapping, it evaluates the postimplementation impact of the Act on groundwater conservation and water availability and assesses its effectiveness in achieving its objectives. This study reveals that the government’s policies favoring wheat and rice have significantly contributed to the expansion of these crops, resulting in imbalanced agricultural practices. While the overall groundwater development in Punjab decreased from 170% in 2009 to 165% in 2017, a district-wise analysis reveals that the fall in the groundwater exploitation level in seven districts outperforms the rise in the exploitation level in the other thirteen districts of the state, showing overall minor or no improvement. This study proposes a multifaceted approach combining command-and-control measures with self-regulation incentives. It highlights the potential of incentivizing farmers to adopt sustainable practices, diversify crops, and implement water-efficient technologies. This paper also suggests the importance of involving stakeholders and the community in groundwater management, emphasizing the need for participatory approaches to ensure the long-term sustainability of water resources. While this study provides valuable insights, it is essential to acknowledge that its scope is limited to a qualitative assessment, and there may be challenges in generalizing the findings to all regions facing groundwater depletion. Full article

Groundwater is a valuable source of water for human consumption, and its quality is a current issue worldwide. Understanding carbon and water cycling presents the basis of biogeochemical reactions occurring in the aquifer; therefore, understanding their interaction is imperative for sustainable water management. In the paper, this interaction was investigated within the complex surface water (SW)–groundwater (GW) system in the Varaždin region (Croatia) by using a multi-parameter approach: δ¹³C_DIC values, carbon species (DIC, DOC), δ¹⁸O and δ²H values, geochemical indicators (T, pH, DO, EC), and δ¹³C measurements in solids. Both δ¹⁸O/δ²H and δ¹³C_DIC were recognized as good indicators to differentiate shallow and deep GW. Transit time of water (TT) was evaluated as an important parameter in controlling carbon cycling within the SW–GW system. Shallow GW is characterized by shorter TT, seasonal changes in carbon species and δ¹³C_DIC, and lower possibility of carbon capture in the system. Deep GW has longer TT without pronounced seasonal changes in carbon species and δ¹³C_DIC. The conceptual model of the carbon cycle revealed major sources and sinks of CO₂ in the study area. Our results suggest that GW acts as both source and sink for CO₂, depending on the prevailing geochemical process. Surface waters are primarily a source of CO₂, excluding the gravel pit, which acts primarily as a sink for CO₂. Our study shows that the current SW–GW dynamics regulate carbon balance without having negative impacts on groundwater quality but also demonstrates that implementing carbon cycle in water management studies is of vital importance for sustainable use of groundwater. Full article

Quantification of the water budget of an arid inland river ecosystem is essential but still a challenge for the sustainable development of water resources. In situ observed data were used to analyze the monthly and annual water budgets and the soil hydrological cycle for six typical ecosystems in the Heihe River Basin (HRB). The two-source model was used to partition evapotranspiration (ET) into transpiration (T) and evaporation, after which the validated model was applied to quantitatively analyze the biological water use fraction [T/Ecosystem Water Supply (WS)] for different ecosystems. There were differences in the water budgets of the different ecosystems due to differences in climate, vegetation, soil, and external inputs. Precipitation in the HRB decreased from upstream to downstream, whereas there was a gradual increase in ET. External sources of water (e.g., natural runoff from upstream, irrigation in the middle reaches, and groundwater recharge in the lower reaches) to soil layers played an important role in regulating the water budgets of HRB ecosystems. Cropland obtained the maximum biological water use fraction (0.50), followed by Populus euphratica (0.49), alpine meadow (0.49), alpine swamp meadow (0.44), Tamarix ramosissima (0.42), and Kalidium foliatum (0.4). The soil water residence time (at a depth of 40 cm) varied from 14 d to 97 d (average of 60 d). The order of plant species in terms of soil water residence time was: K. foliatum (88 d) > T. ramosissima (72 d) > alpine meadow (68 d) > alpine swamp meadow (63 d) > cropland (53 d) > P. euphratica forest (20 d). Differences in the biological water use fraction and soil water residence time could be attributed to the characteristics of the water budget for each ecosystem. This study quantified the water budget, biological water use, and soil hydrological cycle across typical ecosystems in HRB, and can act as a reference for ecosystem management of the arid inland river basin. Full article

California has unsustainable use of agricultural water and energy, as well as problems of severe drought, nitrate pollution and groundwater salinity. As the leading producer and exporter of agricultural produce in the United States, 5.6 percent of California’s energy is currently used for pumping groundwater. These problems and new regulatory policies (e.g., Sustainable Groundwater Management Act, Irrigated Lands Regulatory Program) pressure growers to schedule, account and maintain records of water, energy and nutrients needed for crop and soil management. Growers require varying levels of decision support to integrate different irrigation strategies into farm operations. Decision support can come from the public or private sector, where there are many tradeoffs between cost, underlying science, user friendliness and overall challenges in farm integration. Thus, effective irrigation management requires clear definitions, decision support and guidelines for how to incorporate and evaluate the water–nutrient–energy nexus benefits of different practices and combinations of practices under shifting water governance. The California Energy Commission-sponsored Energy Product Evaluation Hub (Cal-EPE Hub) project has a mission of providing science-based evaluation of energy-saving technologies as a direct result of improved water management for irrigation in agriculture, including current and future irrigation decision support systems in California. This project incorporates end-user perceptions into evaluations of existing decision support tools in partnership with government, agricultural and private stakeholders. In this article, we review the policy context and science underlying the available irrigation decision support systems (IDSS), discuss the benefits/tradeoffs and report on their efficacy and ease of use for the most prevalent cropping systems in California. Finally, we identify research and knowledge-to-action gaps for incorporating irrigation decision support systems into new incentives and requirements for reporting water and energy consumption as well as salinity and nitrogen management in the state of California. Full article

Human activities mostly impact the trend and direction of rainwater, groundwater, and other river basin resources in the watershed in Africa. These activities alter river flows and the quality of usable water supplies at both highlands and lowlands. A watershed is indeed a conserved area of land that collects rain, sleet and snow, and empties or penetrates groundwater sources. The act of managing the activities around the watershed is integrated watershed management, which considers the social, economic, and environmental issues in tandem with the human, institutional, natural, and sustainability systems, which are the key drivers as identified in this study, as well as community interests and participation, to manage groundwater resources sustainably. These watersheds, river basins, and groundwater resources provide important services for communities and biodiversity. This paper reveals that the best way to protect groundwater resources is on a watershed basis using sustainable management measures. This technique enables us to handle a variety of concerns and objectives while also allowing us to plan in a complicated and uncertain environment. Sustaining a regional and sub-regional watershed involves cooperation and participation from a wide range of community interests and water users, including municipalities, companies, people, agencies, and landowners, for stakeholders’ input to be successful. All of the strategies and plans are produced with regard to one another, as well as the overall conditions of the watershed, local land uses, and specific regional transboundary issues. Full article

Groundwater is an essential source of drinking and irrigation water. However, elevated Fe and Mn concentrations in groundwater have been found in recent decades, which can adversely affect human health and decrease crop quality and yields. The roles of hydrogeochemical changes and groundwater pollution (exogenous reductive material inputs) in this have not been studied adequately. We determined the distribution of Fe and Mn concentrations in groundwater in the Songnen Plain, northeast China, which is known for elevated Fe and Mn concentrations, and investigated the factors and mechanisms involved in causing the elevated concentrations. Chemical and statistical analyses indicated that the Fe and Mn concentrations in groundwater significantly correlated with climate parameters (precipitation and temperature), surface features (altitude, distance from a river, soil type, soil texture, and land use type) and hydrogeochemical characteristics (chemical oxygen demand and NH₄⁺, NO₃⁻, and P concentrations). In particular, the Fe and Mn concentrations in groundwater are higher in areas containing paddy fields and water bodies than other land use type areas. Areas with groundwater containing ultra-high Fe and Mn concentrations have almost all of the favorable factors. The main reasons for the elevated Fe and Mn concentrations in groundwater in the study area are the Fe/Mn mineral-rich strata and soil with abundant organic matter acting as sources of Fe and Mn to the groundwater and the reductive environment in the lower terrain and areas containing water bodies favoring Fe and Mn dissolution in the groundwater. Inputs of pollutants from agricultural activities have caused the Fe and Mn concentrations in groundwater to increase. Future studies should be performed to study interactions between pollutants from agricultural activities and Fe and Mn in groundwater and develop environmental management strategies for preventing future increases in Fe and Mn concentrations and promoting sustainable development of agriculture. Full article

The Sustainable Groundwater Management Act (SGMA) of 2014 and the Central Valley Salinity Alternatives for Long-Term Sustainability (CVSALTS) initiative were conceived to reverse years of inaction on the over-pumping of groundwater and salination of rivers that both threaten agricultural sustainability in the State of California. These largely stakeholder-led, innovative policy actions were supported by modern tools of remote sensing and Geographic Information System technology that allowed stakeholders to make adjustments to existing resource management and jurisdictional boundaries to form policy-mandated Groundwater Sustainability Agencies (GSAs) and Salinity Management Areas (SMAs) to address future management responsibilities. Additional resources mobilized by the California Department of Water Resources (CDWR) and other water resource and water quality management agencies have been effective in encouraging the use of spreadsheet accounting and numerical simulation models to develop robust and coherent quantitative understanding of the current state and likely problems that will be encountered to achieve resource sustainability. This activity has revealed flaws and inconsistencies in the conceptual models underpinning this activity. Two case studies are described that illustrate the disparity in the challenges faced by GSAs in subregions charged with developing consensus-based Groundwater Sustainability Plans (GSPs). These case studies also illustrate the unique aspect of SGMA: that alongside mandates and guidelines being imposed statewide, local leadership and advocacy can play an important role in achieving long-term SGMA and CVSALTS goals. Full article

The Indus basin of Pakistan occupies about 16 million ha (Mha) of land. The Indus River and its tributaries are the primary sources of surface water. An estimated 122 km³ of surface water is diverted annually through an extensive canal system to irrigate this land. These surface water supplies are insufficient to meet the crop water requirements for the intensive cropping system practiced in the Indus basin. The shortfall in surface water is met by exploiting groundwater. Currently, about 62 km³ of groundwater is pumped annually by 1.36 million private and public tube wells. About 1.0 million tubewells are working only in the Punjab province. Small private tubewells account for about 80% of the pumped volume. Inadequate water allocation along the irrigation canals allows excessive water use by head-end farmers, resulting in waterlogging. In contrast, the less productive use of erratic supplies by tail-end farmers often results in soil salinity. The major issues faced by irrigated agriculture in Pakistan are low crop yields and water use efficiency, increasing soil salinization, water quality deterioration, and inefficient drainage effluent disposal. Currently, 4.5 Mha (about 30% of the total irrigated area) suffers from adverse salinity levels. Critical governance issues include inequitable water distribution, minimizing the extent to which salt is mobilized, controlling excessive groundwater pumping, and immediate repair and maintenance of the infrastructure. This paper suggests several options to improve governance, water and salt management to support sustainable irrigated agriculture in Pakistan. In saline groundwater areas, the rotational priorities should be reorganized to match the delivery schedules as closely as possible to crop demand, while emphasizing the reliability of irrigation schedules. Wherever possible, public tubewells should pump fresh groundwater into distributaries to increase water availability at the tail ends. Any substantial reform to make water delivery more flexible and responsive would require an amendment to the existing law and reconfiguration of the entire infrastructure, including thousands of kilometers of channels and almost 60,000 outlets to farmer groups. Within the existing political economy of Pakistan, changing the current water allocation and distribution laws without modernizing the infrastructure would be complicated. A realistic reform program should prioritize interventions that do not require amendment of the Acts or reconstruction of the entire system and are relatively inexpensive. If successful, such interventions may provide the basis for further, more substantial reforms. The present rotational water supply system should continue, with investments focusing on lining channels to ensure equitable water distribution and reduce waterlogging at the head ends. Besides that, the reuse of drainage water should be encouraged to minimize disposal volumes. The timely availability of farm inputs can improve individual farmers’ productivity. Farmers will need to have access to new information on improved irrigation management and soil reclamation approaches. Simultaneously, the government should focus more on the management of drainage and salinity. Full article

A combined hydrogeochemical and hydrodynamic characterization for the assessment of key aspects related to groundwater resources management was performed in a highly productive agricultural basin of the Thessaly region in central Greece. A complementary suite of tools and methods—including graphical processing, hydrogeochemical modeling, multivariate statistics and environmental isotopes—have been applied to a comprehensive dataset of physicochemical analyses and water level measurements. Results revealed that the initial hydrogeochemistry of groundwater was progressively impacted by secondary phenomena (e.g., ion exchange and redox reactions) which were clearly delineated into distinct zones according to data processing. The progressive evolution of groundwater was further verified by the variation of the saturation indices of critical minerals. In addition, the combined use of water level measurements delineated the major pathways of groundwater flow. Interestingly, the additional joint assessment of environmental isotopes revealed a new pathway from E–NE (which had never before been validated), thus highlighting the importance of the joint tools/methods application in complex scientific tasks. The application of multivariate statistics identified the dominant processes that control hydrogeochemistry and fit well with identified hydrodynamic mechanisms. These included (as dominant factor) the salinization impact due to the combined use of irrigation water return and evaporitic mineral leaching, as well as the impact of the geogenic calcareous substrate (mainly karstic calcareous formations and dolostones). Secondary factors, acting as processes (e.g., redox and ion exchange), were identified and found to be in line with initial assessment, thus validating the overall characterization. Finally, the outcomes may prove to be valuable in the progression toward sustainable groundwater resources management. The results have provided spatial and temporal information for significant parameters, sources, and processes—which, as a methodological approach, could be adopted in similar cases of other catchments. Full article

This paper reports an empirical evaluation of a new serious game created to foster learning about collaborative management of common pool resources. Stakeholders (n = 41) involved in the implementation of California’s Sustainable Groundwater Management Act were recruited to play a new serious game designed to illustrate how alternative water management strategies, including pumping restrictions and simple trading schemes, affect supply. In the game, a group of six players set in a groundwater basin area enact the allocation, needs, and use of water in rounds representing annual seasons. Pre-post surveys found that the gameplay increased perceived interdependence among stakeholders, and optimism about the groundwater management process. Qualitative feedback suggested that participants gained new insights into the nature of common pool resources and the needs of other stakeholders. Serious games may be useful in fostering attitudes, such as interdependence needed for successful collaborative planning and governance. Full article

This paper provides a chronology and overview of events and policy initiatives aimed at addressing irrigation sustainability issues in the San Joaquin River Basin (SJRB) of California. Although the SJRB was selected in this case study, many of the same resource management issues are being played out in arid, agricultural regions around the world. The first part of this paper provides an introduction to some of the early issues impacting the expansion of irrigated agriculture primarily on the west side of the San Joaquin Valley and the policy and capital investments that were used to address salinity impairments to the use of the San Joaquin River (SJR) as an irrigation water supply. Irrigated agriculture requires large quantities of water if it is to be sustained, as well as supply water of adequate quality for the crop being grown. The second part of the paper addresses these supply issues and a period of excessive groundwater pumping that resulted in widespread land subsidence. A joint federal and state policy response that resulted in the facilities to import Delta water provided a remedy that lasted almost 50 years until the Sustainable Groundwater Management Act of 2014 was passed in the legislature to address a recurrence of the same issue. The paper describes the current state of basin-scale simulation modeling that many areas, including California, are using to craft a future sustainable groundwater resource management policy. The third section of the paper deals with unique water quality issues that arose in connection with the selenium crisis at Kesterson Reservoir and the significant threats to irrigation sustainability on the west side of the San Joaquin Valley that followed. The eventual policy response to this crisis was incremental, spanning two decades of University of California-led research programs focused on finding permanent solutions to the salt and selenium contamination problems constraining irrigated agriculture, primarily on the west side. Arid-zone agricultural drainage-induced water quality problems are becoming more ubiquitous worldwide. One policy approach that found traction in California is an innovative variant on the traditional Total Maximum Daily Load (TMDL) approach to salinity regulation, which has features in common with a scheme in Australia’s Hunter River Basin. The paper describes the real-time salinity management (RTSM) concept, which is geared to improving coordination of west side agricultural and wetland exports of salt load with east side tributary reservoir release flows to improve compliance with river salinity objectives. RTSM is a concept that requires access to continuous flow and electrical conductivity data from sensor networks located along the San Joaquin River and its major tributaries and a simulation model-based decision support designed to make salt load assimilative capacity forecasts. Web-based information dissemination and data sharing innovations are described with an emphasis on experience with stakeholder engagement and participation. The last decade has seen wide-scale, global deployment of similar technologies for enhancing irrigation agriculture productivity and protecting environmental resources. Full article

In many areas of the world, groundwater resources are increasingly stressed, and unsustainable use has become common. Where existing mechanisms for governing groundwater are ineffective or nonexistent, new ones need to be developed. Local level groundwater governance provides an intriguing alternative to top-down models, with the promise of enabling management to better match the diversity of physical and social conditions in groundwater basins. One such example is emerging in California, USA, where new state law requires new local agencies to self-organize and act to achieve sustainable groundwater management. In this article, we draw on insights from research on common pool resource management and natural resources governance to develop guidelines for institutional design for local groundwater governance, grounded in California’s developing experience. We offer nine criteria that can be used as principles or standards in the evaluation of institutional design for local level groundwater governance: scale, human capacity, funding, authority, independence, representation, participation, accountability, and transparency. We assert that local governance holds promise as an alternative to centralized governance in some settings but that its success will depend heavily on the details of its implementation. Further, for local implementation to achieve its promise, there remain important complementary roles for centralized governance. California’s developing experience with local level groundwater management in dozens of basins across the state provides a unique opportunity to test and assess the importance and influence of these criteria. Full article

Korea has been operating groundwater monitoring systems since 1996 as the Groundwater Act enacted in 1994 enforces nationwide monitoring. Currently, there are six main groundwater monitoring networks operated by different government ministries with different purposes: National Groundwater Monitoring Network (NGMN), Groundwater Quality Monitoring Network (GQMN), Seawater Intrusion Monitoring Network (SIMN), Rural Groundwater Monitoring Network (RGMN), Subsidiary Groundwater Monitoring Network (SGMN), and Drinking Water Monitoring Network (DWMN). The Networks have a total of over 3500 monitoring wells and the majority of them are now equipped with automatic data loggers and remote terminal units. Most of the monitoring data are available to the public through internet websites. These Networks have provided scientific data for designing groundwater management plans and contributed to securing the groundwater resource particularly for recent prolonged drought seasons. Each Network, however, utilizes its own well-specifications, probes, and telecommunication protocols with minimal communication with other Networks, and thus duplicate installations of monitoring wells are not uncommon among different Networks. This mini-review introduces the current regulations and the Groundwater Monitoring Networks operated in Korea and provides some suggestions to improve the sustainability of the current groundwater monitoring system in Korea. Full article