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Water resource planners and managers in the Mid‐Atlantic United States typically determine the sufficiency of water supplies to meet demand by comparing (1) water use as reported to the state by individual water users to (2) metrics of water availability calculated from observed water monitoring networks. This paper focuses on determining whether this means of measuring water use is sufficient for proactive and sustainable management of water resources. The Potomac basin study area illustrates the point that, while state‐reported water use databases typically cover the largest individual water users, unreported water uses can cumulatively comprise a substantial portion of the overall water use. If left unaccounted for, the system is vulnerable to human demand exceeding supplies, with attendant detrimental effects to aquatic habitats and organisms, especially given the exacerbating effects of climate change on the variability of water supplies. Planners and managers are therefore encouraged to consider the full spectrum of water uses, regardless of state reporting requirements. [ABSTRACT FROM AUTHOR]

Real water saving is a important concept in water resources management, which can express previous failures in reducing agricultural water consumption, despite increasing irrigation efficiency. In the present research, while calculating the water requirement for the cultivation of the cropping pattern document in Khuzestan province of Iran and harvesting the intended yield, the crop substitution and changing the planting date method (in four scenarios) has been considered as a sustainable solution to reduce the actual agricultural water consumption. Scenarios 1 to 4, respectively, included replacing part of the cultivated area of sugarcane, fodder corn, and rice with sugar beet, fodder sorghum, and sesame, in 3 consecutive years, and changing the planting date of watermelon and tomato from summer to winter in 1 year. For this purpose, the actual evapotranspiration was determined using FAO-56 Penman–Monteith equations and the expected crop yield at the county scale. Then, using the history of cultivation of different crops in each county and the subwatershed map of the Khuzestan province, the actual evapotranspiration, net irrigation requirement, and water withdrawal from rivers in each subwatershed of Khuzestan province were determined. Results showed that implementation of scenarios 1, 2, 3, and 4 can reduce 551, 25, 194, and 79 hm3 of actual water consumption and decreases 2,160, 104, 775, and 303 hm3 of water withdrawal, respectively. If all the scenarios are implemented together, it can be expected that the reduction in actual agricultural water consumption and its water withdrawal will be equivalent to 5% and 20% of the rivers discharge in Khuzestan province, with a probability of 80%. By considering the real water saving, economic, and social criteria, it can be concluded that replacing sugarcane with sugar beet is the first priority of implementation, whereas changing rice with sesame is the last priority of implementation. Practical Applications: Water reduction consumption is one the most challenging issues in agricultural water management. We know that agriculture consumes mostly fresh water to produce all kinds of agricultural products. The water is converted from liquid to vapor and removed from the target catchment area by atmospheric currents. Therefore, one of the most useful ways to reduce actual water consumption in agriculture is to improve the cropping pattern. Modifying the cropping pattern can challenge the indigenous knowledge of farmers and affect their habits as well as reduce the income of local communities in some cases. Therefore, it is important to pay attention to the profit of the replaced crop and the level of familiarity of the farmer with how to cultivate it in determining the cropping pattern. This research examines the modification of the cropping pattern in Khuzestan province of Iran, which includes replacement of sugarcane, fodder corn, and rice with sugar beet, sorghum, and sesame, respectively, to reduce agricultural water consumption. For this purpose, the reduction of water consumption, reduction of farmer's income, and social tendencies have been seen in the defined scenarios. [ABSTRACT FROM AUTHOR]

Estimation of human water withdrawals is more important now than ever due to uncertain water supplies, population growth, and climate change. Fourteen percent of the total water withdrawal in the United States is used for public supply, typically including deliveries to domestic, commercial, and occasionally including industrial, irrigation, and thermoelectric water withdrawal. Stewards of water resources in the USA require estimates of water withdrawals to manage and plan for future demands and sustainable water supplies. This study compiled the most comprehensive conterminous United States water withdrawal data set to date and developed a machine learning framework for estimating public supply withdrawals and associated uncertainty for the period 2000–2020. The modeling approach provides service area resolution estimates to allow for annual and monthly water withdrawal estimation while incorporating a complex array of driving factors that include hydroclimatic, demographic, socioeconomic, geographic, and land use factors. Model results reveal highly variable and lognormally distributed per‐capita water withdrawal, spanning from 30 to 650 gallons per capita per day (GPCD), across community, regional, and national scales, with pronounced seasonal variations. Analysis of estimated withdrawal trends indicates that the national annual average withdrawal experienced a decline at a rate of 0.58 GPCD/year during the period from 2000 to 2020. Model interpretation reveals a complex interplay between public supply withdrawal and key predictors, including population size, warm‐season precipitation, counts of large buildings and houses, and areas of urban and commercial land use. The developed models can forecast future public supply driven by various climate, demographic, and socioeconomic scenarios. Key Points: Consistent, reproducible estimates of monthly water withdrawals were generated at the spatial resolution of USA water service areasSpatial and temporal variability of public supply withdrawal is driven by a complex array of explanatory featuresAn operational machine learning framework was developed to estimate water withdrawals, prediction uncertainty, and feature importance [ABSTRACT FROM AUTHOR]

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Coal-fired power generation occupies a dominant position in China's power sector and is known for its high water requirement. Limited research exists on how water withdrawal for coal-fired power generation responds to policy and technical factors, as well as spatial variations in the future. To address this gap, this study utilizes a geospatial dataset at the coal-fired power unit level and an improved calculation method for water withdrawal to investigate the evolving trend of water withdrawal in coal-fired power generation, considering the influences of carbon emission reduction, adaptive water-saving measures, and phaseout strategies. The results demonstrate that the improved water withdrawal calculation method yields superior simulation outcomes compared to existing approaches. The study reveals substantial variations in coal-fired power generation under different carbon emission reduction scenarios. Despite the business-as-usual (BAU) scenario where coal-fired power generation continues to dominate the power sector, implementing various adaptive water-saving scenarios results in national water withdrawal estimates ranging from 42.9 to 59.4 billion m3 in 2050. In contrast, water withdrawal is reduced by 37.6% to 42.9% under the 2.0℃ target scenario and by 86.5% to 97.5% under the 1.5℃ target scenario. Technological advancements play a crucial role in reducing water withdrawal for coal-fired power generation, particularly in northwest China. The transformation of cooling systems significantly decreases water withdrawal nationwide and in the regions that predominantly relied on once-through cooling. The deployment of carbon capture and storage (CCS) technology in coal-fired power plants in the northwest region creates short-term pressure on regional water resources. Under strict carbon emissions constraints, adopting the phaseout strategy with guaranteed lifetime results in relatively higher water withdrawal for coal-fired power generation, and the variations in coal-fired power plants configuration across provinces lead to different responses in water withdrawal changes when facing the same unit retirement strategy.

Enhancing the comprehension of alterations in land use holds paramount importance for water management in semi-arid regions due to its effects on hydrology and agricultural economics. Allowing agricultural land to lie fallow has emerged as a technique to decrease water use. This research employs the methodology of system dynamics modeling to evaluate the hydrologic and agricultural economic ramifications of employing the fallowing strategy, which aims to preserve water resources in interconnected socio-hydrologic systems. This strategy is explored across three different crops, focusing on the Mesilla–Rincon Valley (MRV) in southern New Mexico. The study's timeline spans from 2022 to 2050 with historical background from 1969 and encompasses various dimensions, including water availability, land utilization, and agricultural economics. Three types of crops were selected for the fallowing strategy, including cotton, alfalfa/hay, and chile. For each crop, 2500 acres of it would be designated for fallowing separately in two subsequent years, allowing the land to be cultivated in the third year and recurring such pattern. Simulation findings across scenarios (GFDL, UKMO, and NCAR) indicate that water withdrawals for all crops decreased significantly, ranging from approximately 2.69% to 4.37%. Similarly, agriculture income experienced reductions, varying from around 1.53% to 2.26%. Also, surface water and groundwater withdrawals are represented as percentages. The data illustrate significant reductions in water withdrawals across all scenarios. For instance, in the GFDL scenario, surface water withdrawal decreased by approximately 1.85% for cotton, 2.56% for alfalfa/hay, and 1.58% for chile. Similarly, groundwater withdrawals saw substantial reductions, such as 14.93% for cotton, 20.44% for alfalfa/hay, and 12.62% for chile. These numbers emphasize the urgent need for sustainable water management practices to address the challenges posed by reduced water availability. [ABSTRACT FROM AUTHOR]

Assessment of nutritional water productivity (NWP) combines a metric of crop or livestock production per unit water consumed and human nutritional value of the food produced. As such, it can rationalize the use of scarce water for a portfolio of crop and livestock production systems that jointly match human nutritional needs and reduce water scarcity impacts. However, a comprehensive search and review of 40 NWP studies highlighted that current NWP studies vary widely in terms of their methodological approaches, the data and tools used and the water flows and nutrient content accounted for. Most of the studies accounted for evapotranspiration stemming from precipitation and technical water, and/or inclusion of the withdrawn technical water. Water scarcity was only addressed in four studies. The reported NWP values also varied for accounting of macro- (energy, protein, fat and carbohydrates) and micro-nutrient (minerals and vitamins) content. The methodological differences, however, severely limit the informative value of reported NWP values. A multidisciplinary research effort is required to further develop standardized metrics for NWP, including its local environmental water scarcity impacts. A robust NWP analysis framework in agriculture should focus on the integration of assessments of NWP and water scarcity impact (WSI), and development of more field measurements and locally calibrated and validated agrohydrological and farm production models to quantify reliable NWP values and their associated WSI of agriculture production systems worldwide. [ABSTRACT FROM AUTHOR]

The High Plains aquifer (HPA) is the primary water source for agricultural irrigation in the US Great Plains. The water levels in many locations of the aquifer have declined steadily over the past several decades because the rate of water withdrawals exceeds recharge, which has been a serious concern to the water resources management in the region. We evaluated temporal trends and variations in agricultural water use and hydroclimatic variables including precipitation, air temperature, reference evapotranspiration, runoff, groundwater level, and terrestrial water storage across the HPA region for different periods from 1985 to 2020 at the grid, county, or region scale. The results showed that water withdrawals decreased from 21.3 km3/year in 1985 to 18.2 km3/year in 2015, while irrigated croplands increased from 71,928 km2 in 1985 to 78,464 km2 in 2015 in the entire HPA. The hydroclimatic time‐series showed wetting trends in most of the northern HPA, but drying and warming trends in the southern region from 1985 to 2020. The groundwater level time‐series indicated flat trends in the north, but significant declining in the central and southern HPA. Trends in irrigation water withdrawals and irrigation area across the HPA were controlled by the advancement of irrigation systems and technologies and the management of sustainable water use, but also were affected by dynamical changes in the hydroclimatic conditions. [ABSTRACT FROM AUTHOR]

Quantifying the contributions of climate change (CC) and human activities (HA) to streamflow alteration is significant for effective water resources management. However, numerous studies fail to differentiate the individual impacts of various HA on streamflow. In this study, a comprehensive streamflow attribution framework that incorporates climate, vegetation, and water withdrawal (WW) was proposed. In this framework, traditional streamflow attribution methods such as statistical analysis (Double Mass Curve and Slope Change Ratio of Accumulative Quantity), elasticity (Budyko), and modeling simulation (Variable Infiltration Capacity and Long Short-term Memory) are employed to separate the influence of meteorological factors (MF) on streamflow. Subsequently, the impacts of WW on streamflow are assessed using global WW data. The Residual Analysis method is utilized to quantify the effects of vegetation alteration caused by both CC (Lcc) and HA (Lha) on streamflow alteration. To demonstrate the applicability of our proposed framework, two stations, Xianyang and Huaxian, located within the Weihe River Basin in Northwest China were selected as the case study area. The results demonstrated that compared to the baseline period (1961–1990), the average contributions of MF, Lcc, Lha, and WW to streamflow reduction during the variation periods (1991–2019) were as follows: for the Xianyang station, 26.0%, 13.5%, 30.9%, and 29.6% respectively; and for the Huaxian station, 28.9%, 5.5%, 17.7%, and 47.9% respectively. Additionally, during the variation periods, the contributions of CC and HA to vegetation variation were 30.5% and 69.5% respectively in Xianyang, and 23.7% and 76.3% respectively in Huaxian. The framework developed herein also provides a solution for quantifying the indirect effects of CC on streamflow through vegetation. [ABSTRACT FROM AUTHOR]

Water management statistics of the state water cadaster of the Republic of Belarus was used to analyze the dynamics of water use over 2000–2019. The study is based on the statistical methods for the analysis of time series and the relative characteristics of water use dynamics. Trends and priorities were revealed in water use in the country as a whole and at the level of administrative regions. It is shown that in 2000–2019, water intake in the country decreased by 28%, and the use of water for drinking and industrial needs dropped by more than 30%. Comparative analysis revealed differences in water use between regions expressed in the relative characteristics: total water intake, the volume of groundwater development and surface water extraction, the amounts of water use for different purposes. In the majority of administrative regions of the country (102 out of 118), the main source of water supply is groundwater, the development of which exceeds the extraction of surface water, and in 36 regions, water supply relies completely on groundwater. The administrative regions are grouped by the priority objectives of water use. It is found that two water use objectives are of priority in 78 regions; these are household and agricultural needs, met by groundwater. The differentiation of the volumes of water withdrawal and water use priorities at the regional level is determined by population size, the development level of material production branches, and their water demand. [ABSTRACT FROM AUTHOR]

Aquifer surveillance is key to understanding the dynamics of groundwater reservoirs. Attention should be focused on developing strategies to monitor and mitigate the adverse consequences of overexploitation. In this context, ground surface deformation monitoring allows us to estimate the spatial and temporal distribution of groundwater levels, determine the recharge times of the aquifers, and calibrate the hydrological models. This study proposes a methodology for implementing advanced multitemporal differential interferometry (InSAR) techniques for water withdrawal surveillance and early warning assessment. For this, large open-access images were used, a total of 145 SAR images from the Sentinel 1 C-band satellite provided by the Copernicus mission of the European Space Agency. InSAR processing was carried out with an algorithm based on parallel computing technology implemented in cloud infrastructure, optimizing complex workflows and processing times. The surveillance period records 6-years of satellite observation from September 2016 to December 2021 over the city of Chillan (Chile), an area exposed to urban development and intensive agriculture, where ~80 wells are located. The groundwater flow path spans from the Andes Mountain range to the Pacific Ocean, crossing the Itata river basin in the Chilean central valley. InSAR validation measurements were carried out by comparing the results with the values of continuous GNSS stations available in the area of interest. The performance analysis is based on spatial analysis, time series, meteorological stations data, and static level measurements, as well as hydrogeological structure. The results indicate seasonal variations in winter and summer, which corresponds to the recovery and drawdown periods with velocities > −10 mm/year, and an aquifer deterioration trend of up to 60 mm registered in the satellite SAR observation period. Our results show an efficient tool to monitor aquifer conditions, including irreversible consolidation and storage capacity loss, allowing timely decision making to avoid harmful exploitation. [ABSTRACT FROM AUTHOR]

Water is one of the natural resource due balance if our planet and the life on it have to sustain and economic development to be expected in the future. The increase in population of the world and level of wealth of humans is expected to withdraw more freshwater. However, since water is already one of the limited resources, global per capital water available surely drops and water shortage happens. Pollution of ground and surface water by dissolved salts are increasing and exacerbating this water shortage situation. The sources of these dissolved salts (such as primary and secondary salinity-causing agents) are known to change the chemical constituent of water. Once contributing factors for water scarcity are identified, future man should work on it to overcome the challenge. This paper therefore began with global water resource information and indicated different levels of scarcity to give overall clues on the situation. Salinity description, its global status, causative factors and challenges were revised before possible recommendations were indicated as indispensable solution.

China’s population–income structure has undergone significant changes. However, the impact of population expansion and changes in consumption patterns of specific income groups on regional water withdrawal has not been quantitatively assessed. Here we incorporate multiregional input–output (MRIO) tables with national survey data to capture the water footprint (WF) in the consumption of each income group in China by considering each group’s consumption patterns and population changes. The results show that the middle and rich classes contributed 83% (2012) and 89% (2015) of embodied water withdrawal, respectively. Among the driving factors leading to changes in water withdrawal, changes in consumption patterns and the population–income structure led to increases of approximately 15.4 billion m3and 12.4 billion m3, respectively. Households on the East Coast (EC), and South Coast (SC), as well as in Central China (CC), and Southwest (SW) were the key contributors to the increase. Our findings highlight essential water conservation policies to consider to meet the needs of transforming society.

Enhancing the comprehension of alterations in land use holds paramount importance for water management in semi-arid regions due to its effects on hydrology and agricultural economics. Allowing agricultural land to lie fallow has emerged as a technique to decrease water use. This research employs the methodology of system dynamics modeling to evaluate the hydrologic and agricultural economic ramifications of employing the fallowing strategy, which aims to preserve water resources in interconnected socio-hydrologic systems. This strategy is explored across three different crops, focusing on the Mesilla–Rincon Valley (MRV) in southern New Mexico. The study’s timeline spans from 2022 to 2050 with historical background from 1969 and encompasses various dimensions, including water availability, land utilization, and agricultural economics. Three types of crops were selected for the fallowing strategy, including cotton, alfalfa/hay, and chile. For each crop, 2500 acres of it would be designated for fallowing separately in two subsequent years, allowing the land to be cultivated in the third year and recurring such pattern. Simulation findings across scenarios (GFDL, UKMO, and NCAR) indicate that water withdrawals for all crops decreased significantly, ranging from approximately 2.69% to 4.37%. Similarly, agriculture income experienced reductions, varying from around 1.53% to 2.26%. Also, surface water and groundwater withdrawals are represented as percentages. The data illustrate significant reductions in water withdrawals across all scenarios. For instance, in the GFDL scenario, surface water withdrawal decreased by approximately 1.85% for cotton, 2.56% for alfalfa/hay, and 1.58% for chile. Similarly, groundwater withdrawals saw substantial reductions, such as 14.93% for cotton, 20.44% for alfalfa/hay, and 12.62% for chile. These numbers emphasize the urgent need for sustainable water management practices to address the challenges posed by reduced water availability.

Assessment of nutritional water productivity (NWP) combines a metric of crop or livestock production per unit water consumed and human nutritional value of the food produced. As such, it can rationalize the use of scarce water for a portfolio of crop and livestock production systems that jointly match human nutritional needs and reduce water scarcity impacts. However, a comprehensive search and review of 40 NWP studies highlighted that current NWP studies vary widely in terms of their methodological approaches, the data and tools used and the water flows and nutrient content accounted for. Most of the studies accounted for evapotranspiration stemming from precipitation and technical water, and/or inclusion of the withdrawn technical water. Water scarcity was only addressed in four studies. The reported NWP values also varied for accounting of macro- (energy, protein, fat and carbohydrates) and micro-nutrient (minerals and vitamins) content. The methodological differences, however, severely limit the informative value of reported NWP values. A multidisciplinary research effort is required to further develop standardized metrics for NWP, including its local environmental water scarcity impacts. A robust NWP analysis framework in agriculture should focus on the integration of assessments of NWP and water scarcity impact (WSI), and development of more field measurements and locally calibrated and validated agrohydrological and farm production models to quantify reliable NWP values and their associated WSI of agriculture production systems worldwide.

Study region: Northern part of China (NPC) Study focus: Along with rapid economic development and population growth, the NPC has been identified as a water scarcity hotspot. Previous studies attributed the intensified water scarcity primarily to increasing human water withdrawal over the NPC in the 20th century. However, water withdrawal has stagnated since the beginning of 21st century, which raises a question of whether the trend of water scarcity changes, particularly when considering the contribution of water availability that is subject to climate variability. Based on the water stress index (WSI), we detected the trends of water scarcity by a piecewise linear regression approach and investigated their associated drivers in the NPC by using survey-based datasets and hydro-climate model simulations. New hydrological insights for the region: Results show that the trends of WSI changed from positive to negative after 2001. Increased water withdrawal was the dominant factor for the aggravated water scarcity before 2001. However, as the rising precipitation offsets the effect of increasing evapotranspiration, climate change has increased water availability and become the major contributor to the alleviated water scarcity during 2001–2020. Furthermore, future projections suggest that climate change would further alleviate future water scarcity over the NPC by increasing water availability. The results suggest the growing role of climate change in affecting water scarcity, which are significant for guiding regional water policy-making.

Water resources are one of the most important features of the environment to meet human needs. In the current research, morphological, quantitative and qualitative hydrological, and land use factors as well as the combined factor, which is the combination of effective variables of the aforementioned factors, have been used to estimate River Water Withdrawal (RWW) for agricultural uses. Lavasanat and Qazvin are selected as study areas, located in the Namak Lake basin in Iran, with Bsk and Csa climate categories, respectively. Estimation of RWW is performed using single and Wavelet–hybrid (W-hybrid) data-driven methods, including Artificial Neural Networks (ANNs), Wavelet–ANN (WANNs), Adaptive Neuro-Fuzzy Inference System (ANFIS), Wavelet–ANFIS (WANFIS), Gene Expression Programming (GEP), and Wavelet–GEP (WGEP). Due to the evaluation criteria, the performance of the WGEP model is the best among the others for estimating RWW variables in both study areas. Considering the W-hybrid models with data de-noising for estimating RWW in the Lavasanat and Qazvin study areas, the obtained values of RMSE for WGEP11 to WGEP15 and WGEP21 to WGEP25 equal 67.268, 54.659, 80.871, 50.796, 15.676 and 105.532, 96.615, 105.018, 160.961, 44.332, respectively. The results indicate that WGEP and ANN are the best and poorest models in both study areas without regarding climate condition effects. Also, a combined factor which includes River Width (RW), minimum flow rate (QMin), average flow rate (QMean), Electrical Conductivity (EC), and Cultivated Area (CA) variables is introduced as the best factor to estimate RWW variables compared with the other factors in both the Bsk and Csa climate categories. On the other hand, qualitative hydrological and land use factors were the weakest ones to estimate RWW variables in the Bsk and Csa climate categories, respectively. Therefore, the current study explores how the mathematical relations for estimating RWW have a significant effect on water resources management and planning by policymakers in the future. HIGHLIGHTS River Water Withdrawal (RWW) for agricultural purposes was estimated using data-driven methods.; The impact of climatic condition, river morphology, quantitative and qualitative hydrological characteristics, and land use features on RWW estimation was assessed.; De-noising the data and developing the combined factor could improve the model's performance.;

Study region: Italy Study focus: Groundwater recharge (GR) is the amount of water that infiltrates into the soil recharging aquifers. For Italy, we applied a water balance method for estimating GR, along with other balance components, using gratis/libre open access data and open source software. The results were compared with the data available from the literature on Central Italy, to validate the model and to investigate the variation in the GR, while considering different lithologies. The comparison of the GR results with anthropogenic water withdrawals enabled the evaluation of sustainable water use in Italy. The proposed approach can provide quantitative data in line with the Goal 6 (Targets 6.4 and 6.5) of the 2030 Agenda for Sustainable Development of United Nations (https://sdgs.un.org). New hydrological insights for the region: In Italy, the annual averaged GR is ~110 × 109 m3. This estimate may vary for specific years; in 1992 and 2015, the GR exceeded the value by 3% and 27%, respectively. According to these and related estimations, the 1981–2010 average groundwater withdrawals for civil, industrial and agricultural use were estimated to be ~14% of the averaged GR for the same period. In 1992, the withdrawals for the mineral water industry was about 0.01% of the GR and that for civil use was ~10% in 2015. In this study, we observed significant differences in the GR at the regional level, mostly influenced by the precipitation distribution and elevation.

Irrigation is the dominant section of human water use, exerting essential impacts on hydrological processes and water resources. To more realistically simulate irrigation processes in water‐rich regions, an irrigation scheme is incorporated into a land surface‐hydrological model. It calculates the irrigation water requirement according to meteorological conditions, cropping area and growing stage, and root‐zone soil moisture, and determines the irrigation water withdrawal based on the available water resources as well as describing water extraction and irrigation processes in the model. The coupled model is applied to the Yangtze River Basin (YRB) in China, and verified using the observed daily river discharge from 1987 to 1990, evapotranspiration and irrigation amounts from 1999 to 2003. The results first show that the model can well reproduce hydrological processes within the basin, and the simulated irrigation largely agrees with the observation, in terms of annual irrigation and its spatial pattern. Second, inclusion of irrigation processes allows the model to better estimate evapotranspiration, with relative biases decreased from about −10% to −3%. It is also found that in comparison to arid/semi‐arid areas, although presenting a less effect on river discharge and groundwater, the irrigation in the YRB significantly alters hydrological processes through water redistribution. The irrigation‐induced evapotranspiration increment and runoff decrease indicate a shift in the surface water and energy balance, implying a potential effect on the atmosphere. Therefore, representing irrigation processes properly is important, particularly for understanding the coupling effect of the nature‐human system and improving the hydrological prediction accuracy. Plain Language Summary: As the human population has dramatically increased, the agricultural irrigation has grown rapidly over the past 200 years. The critical implications of irrigation on water resources exert through impact on hydrological processes and further influence on weather and climate via the surface energy balance. Representing irrigation processes in the hydrological models or in the climate models is meaningful for improving accuracy of hydrological predictions. Therefore, we described irrigation processes in a land surface‐hydrological model, and the coupled model was used for the YRB in China and verified. It has confirmed that the model appropriately reproduces the hydrological processes impacted by climate variability and human activities. In the future, we intend to use the model to study the coupling effect of the nature‐human systems, which is expected to contribute to sustainable water resources management. Key Points: We developed a land surface‐hydrological model that describes irrigation processes by incorporating an irrigation schemeWe used the Global Crop Water Model method to more realistically estimate irrigation and described water extraction and irrigation processesWe conducted verification in terms of river discharge, evapotranspiration, and irrigation water amount to evaluate model performance [ABSTRACT FROM AUTHOR]

With an increase in population and economic development, water withdrawals are close to or even exceed the amount of water available in many regions of the world. Modelling water withdrawals could help water planners improve the efficiency of water use, water resources allocation, and management in order to alleviate water crises. However, minimal information has been obtained on how water withdrawals have changed over space and time, especially on a regional or local scale. This research proposes a data-driven framework to help estimate county-level distribution of water withdrawals. Using this framework, spatial statistical methods are used to estimate water withdrawals for agricultural, industrial, and domestic purposes in the Huaihe River watershed in China for the period 1978–2018. Total water withdrawals were found to have more than doubled, from 292.55 × 108 m3 in 1978 to 642.93 × 108 m3 in 2009, and decreased to 602.63 × 108 m3 in 2018. Agricultural water increased from 208.17 × 108 m3 in 1978 to 435.80 × 108 m3 in 2009 and decreased to 360.84 × 108 m3 in 2018. Industrial and domestic water usage constantly increased throughout the 1978–2018 period. In 1978, industrial and domestic demands were 20.35 × 108 m3 and 60.04 × 108 m3, respectively, and up until 2018, the figures were 105.58 × 108 m3 and 136.20 × 108 m3. From a spatial distribution perspective, Moran's I statistical results show that the total water withdrawal has significant spatial autocorrelation during 1978–2018. The overall trend was a gradual increase in 1978–2010 with withdrawal beginning to decline in 2010–2018. The results of Getis-Ord Gi* statistical calculations showed spatially contiguous clusters of total water withdrawal in the Huaihe River watershed during 1978–2010, and the spatial agglomeration weakened from 2010 to 2018. This study provides a data-driven framework for assessing water withdrawals to enable a deeper understanding of competing water use among economic sectors as well as water withdrawal modelled with proper data resource and method. [ABSTRACT FROM AUTHOR]

Abstract Irrigation is the dominant section of human water use, exerting essential impacts on hydrological processes and water resources. To more realistically simulate irrigation processes in water‐rich regions, an irrigation scheme is incorporated into a land surface‐hydrological model. It calculates the irrigation water requirement according to meteorological conditions, cropping area and growing stage, and root‐zone soil moisture, and determines the irrigation water withdrawal based on the available water resources as well as describing water extraction and irrigation processes in the model. The coupled model is applied to the Yangtze River Basin (YRB) in China, and verified using the observed daily river discharge from 1987 to 1990, evapotranspiration and irrigation amounts from 1999 to 2003. The results first show that the model can well reproduce hydrological processes within the basin, and the simulated irrigation largely agrees with the observation, in terms of annual irrigation and its spatial pattern. Second, inclusion of irrigation processes allows the model to better estimate evapotranspiration, with relative biases decreased from about −10% to −3%. It is also found that in comparison to arid/semi‐arid areas, although presenting a less effect on river discharge and groundwater, the irrigation in the YRB significantly alters hydrological processes through water redistribution. The irrigation‐induced evapotranspiration increment and runoff decrease indicate a shift in the surface water and energy balance, implying a potential effect on the atmosphere. Therefore, representing irrigation processes properly is important, particularly for understanding the coupling effect of the nature‐human system and improving the hydrological prediction accuracy.

Aquifer surveillance is key to understanding the dynamics of groundwater reservoirs. Attention should be focused on developing strategies to monitor and mitigate the adverse consequences of overexploitation. In this context, ground surface deformation monitoring allows us to estimate the spatial and temporal distribution of groundwater levels, determine the recharge times of the aquifers, and calibrate the hydrological models. This study proposes a methodology for implementing advanced multitemporal differential interferometry (InSAR) techniques for water withdrawal surveillance and early warning assessment. For this, large open-access images were used, a total of 145 SAR images from the Sentinel 1 C-band satellite provided by the Copernicus mission of the European Space Agency. InSAR processing was carried out with an algorithm based on parallel computing technology implemented in cloud infrastructure, optimizing complex workflows and processing times. The surveillance period records 6-years of satellite observation from September 2016 to December 2021 over the city of Chillan (Chile), an area exposed to urban development and intensive agriculture, where ~80 wells are located. The groundwater flow path spans from the Andes Mountain range to the Pacific Ocean, crossing the Itata river basin in the Chilean central valley. InSAR validation measurements were carried out by comparing the results with the values of continuous GNSS stations available in the area of interest. The performance analysis is based on spatial analysis, time series, meteorological stations data, and static level measurements, as well as hydrogeological structure. The results indicate seasonal variations in winter and summer, which corresponds to the recovery and drawdown periods with velocities > −10 mm/year, and an aquifer deterioration trend of up to 60 mm registered in the satellite SAR observation period. Our results show an efficient tool to monitor aquifer conditions, including irreversible consolidation and storage capacity loss, allowing timely decision making to avoid harmful exploitation.

The energy system is a major water user, but understanding how much water is consumed and withdrawn for energy is a challenging empirical task: nonevaporative volumetric water use is not easily calculated from first principles. Water use also has impacts that differ in important ways depending on where water is abstracted and used, timing of use, and socioenvironmental context. Moreover, different decarbonization pathways and policy environments have very different water use implications. We currently face a crisis of twin nonstationarities in hydrology and energy systems that make understanding water use for energy critical for decision support as hydroclimate and energy systems change. Currently, water‐for‐energy data are highly uncertain and not centrally collected, which means researchers spend substantial effort collecting inventory data. Recent advances in impact assessment methods for water volumes focus largely on spatially resolved water scarcity evaluations, but robust conclusions can be elusive due to uncertain and low‐metadata inventory information. As water‐for‐energy quantification efforts progress, research should emphasize decision support for energy system design, incorporating crucial hydrologic dynamics. Beyond the location of water use, relative scarcity, and potential competing uses, these include sub‐daily to interannual temporal dynamics, the impacts of climate change on these dimensions, potential feedbacks between energy and water systems, and the impacts of hydrologic variability or change on policy‐based incentive structures. This article reviews prior US‐focused efforts to quantify water use for energy, highlights why these nonstationarities are analytically relevant with a brief policy case study, and highlights research needs for decision support under twin nonstationarities. This article is categorized under:Engineering Water > Sustainable Engineering of WaterEngineering Water > Planning WaterEngineering Water > Methods [ABSTRACT FROM AUTHOR]

We investigate the availability and extent of environmental performance and objectives data reported in corporate social responsibility (CSR) reports published by the world largest food companies. Methods for content analysis that recognize two types of environmental information were implemented for reviewing 75 sustainability reports. Plant‐ and animal‐origin food companies responded to requirements of the Global Reporting Initiative (GRI) standards to communicate about their sustainable development. It was found that plant‐origin food companies' reporting was more compliant with GRI requirements. Information gaps within greenhouse gas (GHG) emissions data have been identified as a common characteristic for both food sectors. The most frequent performance indicators reported by companies were about water withdrawal. Average annual reductions in four major environmental dimensions such as energy consumption, GHG emissions, water withdrawal, and total waste were calculated. These results reveal patterns of food companies' behavior in CSR reporting. [ABSTRACT FROM AUTHOR]

Hydropower development can lead to riverine ecosystem degradation due to flow regime alteration, but also offers an opportunity to reduce water withdrawal from rivers for better maintenance of environmental flows, because hydropower could substitute for water to promote economic development, to some extent. Seizing this opportunity, this research proposes to adjust the water withdrawal volume at the national scale by reducing withdrawal from rivers with environmental flow deficits, and seeks to determine the volume of water withdrawal that could be reduced under the increase of hydropower generation. A computable general equilibrium model (CGE) is established to analyse the balance of water and hydropower from the perspective of economic development. China is adopted as a case study to demonstrate the effectiveness of the method. The results show that the water‐hydropower equivalent decreases with the hydropower yield. When the hydropower yield increases by 10%, 30%, 100% and 150%, the water‐hydropower equivalents are 0.73, 0.54, 0.22 and 0.13 m3/kWh, respectively, and the water compensation rate for hydropower increase is determined accordingly. [ABSTRACT FROM AUTHOR]

For rivers or streams with waterfalls, water withdrawal for multiple uses can lead to potential conflicts of interest. The question arises to what extent water withdrawal impairs the appearance and acoustics of waterfalls. A data set was analyzed of 15 waterfalls of different morphological types in Switzerland, Austria, and Norway. It comprises discharge measurements as well as photo imaging and sound level measurements. The variations of waterfall appearance and sound level decreased after reaching a threshold discharge value for all investigated morphological waterfall types. For low discharges, visible and acoustics changes were more significant compared to higher discharges. Acoustics changes were less pronounced than visual changes. The acoustics and visual extent of a water withdrawal can be calculated with a novel assessment equation using a normalized discharge. Based on an impact intensity, which is a function of the extent of the water withdrawal and the nonmonetary waterfall value, the selected residual discharge can be evaluated. In addition, a software tool was developed to enable a sensitivity analysis of the required residual discharge to maintain a certain waterfall appearance. Key Points: The variation of waterfall appearance and sound level decreases after reaching a threshold discharge valueThe extent of a water withdrawal on waterfall appearance and sound level can be described by a normalized dischargeWater withdrawal extent and waterfall value can be used to set the required residual discharge to maintain a certain waterfall image [ABSTRACT FROM AUTHOR]

The increasing number of water withdrawals in Alpine regions represents a significant threat to aquatic ecosystems and river landscape (riverscape). To assess their sustainability, the impacts on river ecological status and landscape features need to be quantified with appropriate indicators. However, assessment of landscape attributes is a complex challenge, due to the lack of standardized methods. Moreover, few metrics quantifying the impacts of water withdrawal on downstream riverscape perception are available in the scientific literature.In this paper, a new indicator, named Landscape Protection Level (LPL), aimed at assessing the effects of water withdrawals on the river landscape, is presented. The indicator has been developed in Aosta Valley (NW Italian Alps), where the river network is heavily exploited by hundreds of withdrawals for hydropower production and irrigation, and it has been included in a multi-criteria analysis (MCA) procedure to assess the sustainability of water withdrawal licenses in relation to different flow release scenarios.The LPL indicator is based on three parameters, Constraint Factor, Release Factor, and Visual Elements Factor, quantifying the presence of landscape protection constraints, the ratio of flow released downstream of the dam to the available river discharge, and the impact on the visual perception of the bypassed stretch, respectively.Its application in four real case studies of existing hydropower plants is presented and discussed in the paper, demonstrating the indicator applicability to assess both specific release values and flow release scenarios varying over the year. Results are analyzed by highlighting the main strengths and weaknesses of the indicator and proposing some suggestions for future improvements. In particular, the reactiveness of the indicator, the representativeness of the stakeholders’ interests, the transparency of the indicator calculation procedure, and the time required for data collection and processing are discussed. Finally, future activities aimed at further improving the indicator applicability and transferability to different river contexts are proposed.

Water sustainability is central to modern political and academic debates. Despite increasing efforts to promote regional and global integrated water management, climate change, population, and economic growth, and increasing consumption of water-intensive goods project higher water deficiency. Robust economic analyses rely on information about water supply and consumption across different production sectors, type of procurement source (public or private water supply), and water prices. Nevertheless, developing current and future economic water assessments and indicators is impeded by the absence of data. Despite the lack of official national statistics on water withdrawal and consumption, a small number of international and global databases have been constructed and attempt to combine available national water information into databases. Water databases do not commonly define and/or distinguish terms such as water use, water consumption, water supply, or water abstraction, and the associated aspects of water scarcity and sustainability. They comprise variable data quality, provided by numerous sources, and estimated values. This paper evaluates the current state of knowledge of national statistics, international and global water databases. We describe the data collection methods, identify basic concepts and definitions of water terms, followed by the criteria of consistent water databases. We inform about data availability across regions, and present the data content and definitions of national, international, and global water databases. The results show inconsistencies of data content and definitions, suggesting no evidence of data harmonization among databases. Therefore, our study cautions researchers to be careful when manipulating and comparing the available water data, especially when deriving policy recommendations or economic conclusions. In the long run, the headway of water research and political assessments depend on political enforcements to refine the meaningfulness of water data and support water collection, reporting, and monitoring. Alternatively, in the short- and medium-run, water data challenges can be addressed by joint research efforts for water data harmonization. [ABSTRACT FROM AUTHOR]

• Shift in water scarcity and productivity was assessed over China during 1979–2020. • Water scarcity trends turned from upward to downward in the early 21st century. • Accelerating water productivity (WP) was dominated by nonagricultural sector. • The correlation between water scarcity and WP shifted from positive to negative. Increasing water productivity has been viewed as an important strategy for reducing regional water scarcity in many countries, including China. However, some studies argue that improving water productivity may lead to a rebound effect that reversely aggravates water scarcity. This contradictory relationship is because that previous empirical assessments mostly focus on limited time spans, which raises a theoretical hypothesis that their correlation would presumably shift over long-term period under different development stages. Thus, this study performed a comprehensive analysis over China based on multiple survey-based datasets and revealed the shifts in water scarcity and productivity in terms of their trends and correlation during 1979–2020. Results showed significant turning points of water scarcity from upward to downward trends across China in the early 21st century, except in southwestern China where water scarcity continuously intensified. Water productivity showed a widespread accelerating trend because of large increase in nonagricultural water productivity. Furthermore, the correlation between water scarcity and productivity was positive in the early stage of China's development pathway when both of them were low but simultaneously increasing for more profit. Then, their positive correlation shifted to negative in response to the necessity for water scarcity alleviation, and increasing water productivity would be effective to reduce water scarcity with the complement of water-related policies that prevent its rebound effect. The results broadened our knowledge on the long-term evolution of regional water scarcity, and highlighted the changing relationship between water scarcity and productivity that was essential for guiding water policy making. [ABSTRACT FROM AUTHOR]

Abstract In this study, we examine the spatial and temporal characteristics of water stress in China for the historical (1971–2010) and the future (2021–2050) periods using a multimodel simulation approach. Three water stress indices (WSIs), that is, the ratios of water withdrawals to locally generated runoff (WSIR), to natural streamflow (WSIQ), and to natural streamflow minus upstream consumptive water withdrawals (WSIC), are used for the assessment. At the basin level, WSIR estimates generally match the reported data and indicate severe water stress in most northern basins. At the grid cell level, the WSIs show distinct spatial patterns of water stress wherein WSIR (WSIQ) estimates higher (lower) water stress compared to WSIC. Based on the WSIC estimates, 368 million people (nearly one third of the total population) are affected by severe water stress annually during the historical period, while WSIR and WSIQ suggest 595 and 340 million, respectively. Future projections of WSIC indicate that more than 600 million people (43% of the total) might be affected by severe water stress, and half of China's land area would be exposed to stress. The found aggravating water stress conditions could be partly attributed to the elevated future water withdrawals. This study emphasizes the necessity of considering explicit upstream and downstream relations with respect to both water availability and water use in water stress assessment and calls for more attention to increasing levels of water stress in China in the coming decades.

Climate change and changing climatic patterns are posing a threat to the sustainability of life on earth. Climate change is attributed to the accumulation of greenhouse gas emissions (GHG) in the atmosphere representing environmental degradation. This study explores the links of renewable energy, water withdrawal, and economic growth with environmental degradation and provides empirical evidence using the panel data of 166 countries over the period 1990-2017. The study used panel data techniques and reported the results obtained from Pooled OLS, Random Effects, Fixed Effects estimations and 2 Stage Least Square(2SLS). The results support the role of renewable energy in environmental mitigation whereas water withdrawal contributes to emissions. Furthermore, results support the existence of the Environmental Kuznets Curve (EKC). Empirical evidence also suggests the positive role of solar, wind, geothermal and hydroelectricity in environmental improvement. The sensitivity analysis also confirms the robustness of empirical findings. The sensitivity analysis also indicates the validity of Nshaped EKC. The study provides useful insights into the role played by renewable energy in environmental mitigation and water withdrawal in increasing emissions which help to promote the consumption and production of renewable energy and increase its share in the energy mix for environmental mitigation.

The article deals with investigation of the Lake Khanka water resources’ use. We have stated that the predominant development of agriculture determines the water resources use on both the Russian part and the Chinese part of the basin. We have assessed the irrigated land areas and water volumes used for this end, as well as economic activities’ impact of the lake water level. On the basis of statistical data, satellite images and published scientific articles we have assessed for the first time the irrigated lands’ dynamics in the Lake Khanka basin over the 1960–2015 period. Analysis of the official information and the expert-restored data on water withdrawal made it possible firstly to estimate the dynamics of water use for irrigation and establish the values of water consumption (irrevocable water losses) during irrigation in the Russian part of the lake basin for the same period. We have established that the source for irrigating rice crops in Russia is the lake itself. The use of Lake Khanka’s waters in China is possible only in low water years. The influence of water use on irrigation in the Russian part of the basin at the lake level for the entire period of rice cultivation was manifested only in its reduction, and to a very small extent. In high water years, the Lake Malaya Khanka acts as a reservoir for the flood waters of the Mulinghe River, which, if discharged into the Lake Khanka, can have an impact on the growth of the Lake Khanka level.

Abstract Background Thermal stratification in reservoirs is a significant factor affecting water quality, and can be strongly influenced by climate change and operational strategies. Reservoirs in the temperate zone react most sensitively to climate warming during winter as ice cover and inversed stratification are about to disappear in a warmer world. In this study, two well-established hydrodynamic models, the one-dimensional General Lake Model (GLM) and the two-dimensional CE-QUAL-W2 (W2), were used to investigate the response of winter inversed stratification in the Rappbode Reservoir to future climate warming, combined with different water withdrawal elevations. Results Under increased air temperature, the duration of inversed stratification is reduced and the inversion phenomenon will entirely disappear under current management if the air temperature is increased high enough (more than 4.5 K) in the future. Under strong climate warming, the Rappbode Reservoir will therefore change from a dimictic to a monomictic mixing type. Changing the reservoir management from deep withdrawal (e.g., below 350 m a.s.l.) to shallow withdrawal elevations (e.g., above 390 m a.s.l.) reduces internal heat energy stored in the reservoir in summer and prolongs the inversed stratification period in winter. This strategy can retain the dimictic behavior even under strong warming. Conclusions Our study indicates that adjusting the withdrawal elevation is an effective management instrument to control the winter conditions and can, in fact, mitigate climate warming effects on winter hydrodynamics by stabilizing the dimictic mixing type.

The calculation of water consumption for irrigation is critical in maintaining the water supplies for cultivation in tropical catchments. These water withdrawals change seasonally, depending on the rainy and dry seasons. A land-use map is one of the inputs required by hydrological models used to estimate water withdrawals in the basin. However, land-use maps usually offer stagnant details without reflecting the hydrological seasons, associated crop seasons and activities during the year. This research, therefore, assesses the importance of seasonal land-use maps for measuring water withdrawals in the basin. We have developed a crop calendar for the two main seasons (rainy and dry) for the semi-arid Mohgaon basin, Madhya Pradesh, India. Further, two Landsat 8 images from 2016 (March and December) were used to develop seasonal land-use and land-cover (LULC) maps (March: the non-monsoon season, December: the monsoon season). Classifications for land use were made using 10 land-use and land-cover classes for images from both seasons, which were dependent on the crop calendar. In addition, water withdrawals for irrigation were estimated using LULC maps. There were clear variations in land usage between dry and rainy seasons in rain-fed and irrigated areas. The maximum water withdrawal obtained for irrigating paddy crops was calculated at an average of 800 million m³/year (i.e., 56.2 cm/year). This research concluded that accurate seasonal land-use maps are important for quantifying the annual water use for irrigation in catchment areas with distinct dry and rainy seasons. [ABSTRACT FROM AUTHOR]

In the last decades, climatic changes in Mediterranean regions and frequent events of water resource scarcity in supply systems have required addressing the problem of increasing the inflows in storage reservoirs by connecting them to diversion dams. Usually, diversion dams do not have a large storage volume; consequently, these works are not able to regulate monthly flow, and they can divert to reservoirs only a part of river flow. In this field of research, this study aims to provide a procedure to evaluate water volumes withdrawn from diversion dams considering river flows and transfer flows. The procedure is founded by analysing 36 gauging stations in Sardinia (Italy), where a unique regional flow duration curve (FDC) can be defined. The effectiveness of regional evaluation of volume withdrawn, based on a monthly time scale analysis, has been investigated. The methodology allows finding optimal values of regional FDC parameters in order to better evaluate water resources withdrawn from diversion dams with respect to the current estimation used in the Sardinia Region Water Plan (SRWP). The current SRWP (RAS 2006) uses a fixed and extremely precautionary value of the FDC that underestimates withdrawal volumes. Moreover, a correlation analysis has been carried out in order to extend the evaluation of optimal FDC parameters for ungauged basins that allows to improve application of this procedure. Obtained results could allow to update the SRWP as highlighted in the final application to a real water system. [ABSTRACT FROM AUTHOR]

In the context of the freshwater crisis, accounting for water withdrawal could help planners better regulate water use in different sectors to combat water scarcity. However, the water withdrawal statistics in China are patchy, and the water data across all sectors at the city level appear to be relatively insufficient. Hence, we develop a general framework to, for the first time, estimate the water withdrawal of 58 economic–social–environmental sectors in cities in China. This methodology was applied because only inconsistent water statistics collected from different data sources at the city level are available. We applied it to 18 representative Chinese cities. Different from conventional perceptions that agriculture is usually the largest water user, industrial and household water withdrawal may also occupy the largest percentages in the water‐use structure of some cities. The discrepancy among annual household water use per capita in the urban areas of different cities is relatively small (as is the case for rural areas), but that between urban and rural areas is large. As a result, increased attention should be paid to controlling industrial and urban household water use in particular cities. China should specifically prepare annual water accounts at the city level and establish a timetable to tackle water scarcity, which is a basic step toward efficient and sustainable water crisis mitigation. [ABSTRACT FROM AUTHOR]

The interaction between groundwater and surface water plays an important role in the function of riparian ecosystems and sustainable water resource management. Hydraulic fracturing, an unconventional oil and gas well stimulation method, has increased dramatically in North America in an effort to exploit previously inaccessible shale oil and gas reserves. Hydraulic fracturing often requires several thousand cubic meters of water to fracture the source formations. Use of such a high volume of water has raised considerable public concern over the sustainability of this activity and the potential impacts on surface water and groundwater. This paper provides a review of the published literature addressing the effects of water withdrawal for hydraulic fracturing on surface water and groundwater. The potential effects of such withdrawal are: decreased volume of water in rivers, streams, lakes and aquifers; alteration of natural flow regimes; regional water shortages during periods of drought; creating conflicts with other water users in water-stressed regions; inadequate downstream water availability; reduced downstream water quality for human uses, due to less water availability for dilution; and degradation of habitat and aquatic ecosystem function, impacting local wildlife. This review demonstrates that relatively little attention has been paid to quantify and understand these interactions, and suggests that there is a significant need for further research in this area to address the currently limited availability of data. [ABSTRACT FROM AUTHOR]

Chemical equilibria of iron and manganese aqueous species were analyzed at various Eh–pH and aqueous CO2 concentration. Thermodynamic and equilibrium-kinetic simulations were conducted for the oxidations of iron and manganese aqueous species with reference to groundwater demanganation and deironing, using the most probable rate constants of congruent dissolution reactions of iron and manganese carbonates, rate constants of homogeneous iron oxidation, and surface catalytic oxidation of manganese on suspension of iron hydroxide in aqueous solution. A kinetic–thermodynamic model is suggested for iron and manganese oxidation in groundwater under the effect of dissolved oxygen. The numerical simulations show that deironing is relatively effective, whereas the dissolved manganese(II) concentration increases because of slower manganese oxidation and the dissolution of manganese-bearing siderite. Hence, effective groundwater demanganation is possible if the host rocks contain no manganese-bearing siderite. [ABSTRACT FROM AUTHOR]