Declining Groundwater Levels Research Articles

Influence of artificial alteration of groundwater level on vessel lumen area and tree-ring width of Quercus robur

The response of tree-ring widths to groundwater-level decline varies among individual trees in forest stands. By contrast, vessel lumen area series contain common climatic signal of previous summer temperature. Drought events and the overuse of groundwater for water supply can cause significant declines of groundwater levels in naturally poorly drained forest stands. However, the documented growth reactions of trees to declines in groundwater level vary a lot and range from positive because of increased soil aeration to strongly negative because of drought stress. We analysed changes in tree-ring width and earlywood average vessel lumen area of Quercus robur from sites above an artesian aquifer, whose groundwater level declined in the late 1980s by about 5 m due to water pumping. Because we expected different responses of individual trees due to local microtopography and fine root distribution, we performed both site-level and tree-level analyses. Our results show that the site-level response of tree growth to groundwater-level pumping was not uniform. Individual trees were clustered into groups of drought-limited and water abundance-limited individuals. The response of trees to groundwater pumping differed between clusters—drought-sensitive trees responded negatively, whereas the growth of trees limited by water abundance remained stable or slightly increased. Inter-series correlation of drought-limited trees significantly increased in the period with the lowest groundwater level. In contrast to tree-ring widths, earlywood vessel lumen area series contained common temperature signal, with no imprint of groundwater-level alteration. Our results indicate that poorly drained forest ecosystems are characterized by a significantly individualistic response of radial growth to groundwater-level alteration. These individualistic responses could be, however, overshadowed in stand-level average tree-ring width chronologies.

Field investigation of aquifer storage and recovery (ASR) technique to recharge groundwater: a case study in Punjab province of Pakistan

Abstract Fast decline of groundwater levels in Pakistan requires the use of artificial recharging techniques to minimize the adverse effect of over pumping. A study was conducted in the Toba Tek Singh district, Punjab, Pakistan, to investigate aquifer storage and recovery (ASR) technology to recharge groundwater. The facility was developed by drilling a pumping/injection well and constructing the water storage tank along with developing the recharge mechanism. Three treatments of 51, 71, and 99 m3 of treated canal water were injected into the aquifer under gravity and were retained for 7 days. Another three treatments of 100 m3 each were injected for retention times of 14, 28, and 56 days. The recovery efficiency (RE) was found to be 83, 91, and 98% for injected volumes of 51, 71, and 99 m3, respectively, for retention time of 7 days. Similarly, the RE for an injected volume of 100 m3 was found to be 73, 62, and 52% for retention times of 14, 28, and 56 days, respectively. These results indicated that RE improved with increase in injected volume and decreased with increase in retention time; however, the technology was found to have potential for storing and recovering of water injected into the aquifer.

Current and future groundwater withdrawals: Effects, management and energy policy options for a semi-arid Indian watershed

Effects of future expansion/intensification of irrigated agriculture on groundwater and surface water levels and availability in a semi-arid watershed were evaluated using an integrated hydrologic model (MIKE SHE/MIKE 11) in conjunction with biophysical measurements. Improved water use efficiency, water storage, and energy policy options were evaluated for their ability to sustain the future (2035) increased groundwater withdrawals. Three future withdrawal scenarios (low = 20, medium = 30, high = 50 wells/100 km2/year) based on the historical rate of growth of irrigation wells were formulated. While well drying from falling groundwater levels was limited to drought and consecutive below average rainfall years, under the current (2015) withdrawals, significant increases in frequency and duration (17–97 days/year) of well drying along with 13–26% (19–37 mm) reductions in surface flows were predicted under the future withdrawals. Higher (27–108%) energy demands of existing irrigation pumps due to declining groundwater levels and reduced hydroelectric generation due to decreased surface flows would create a vicious water-food-energy nexus in the future. Crop failure, one of the main causes of farmers’ emotional distress and death in the region, is predicted to exacerbate under the future withdrawal scenarios. Shift to negative net recharge (−63 mm) and early and prolonged drying of wells under the high scenario will reduce the groundwater availability and negatively affect crop production in more than 60% and 90% of cropped areas in the Rabi (November–February) and summer (March–May) seasons, respectively during a drought year. Individual and combined demand (drip irrigation and reduced farm electricity subsidy) and supply (water storage) management options improved groundwater levels and reduced well drying by 55–97 days/year compared to business-as-usual management under the high scenario. The combined management (50% drip conversion, 50% reduction in subsidy, and enhanced water storage) mitigated well drying even during drought and consecutive below average rainfall years under the high scenario. A conservative economic evaluation for management options under the high scenario showed increases in crop production and per farmer annual profits by $987–$1397 during a drought year (average household income = $1520/year). A scale-up of results showed that diverting 50% state power subsidy ($6 billion for 3–6 years) can almost entirely fund the conversion to drip irrigation ($4.2 billion) and water storage structures ($2.9 billion) and help meet the water supply demand of a 50% increase in irrigated area under the high scenario. Converting flood to drip irrigation in 50% of irrigated area under the high scenario can reduce the electric energy consumption (7 × 106Mwh/year) and carbon footprint (6000 Mt/year) of groundwater irrigation by 24% in the state. Management options considered can potentially create a sustainable water-food-energy nexus in the larger semi-arid hard rock region. Reducing the power subsidy will require a strong political will since it has been used as a tool to win the elections in India. Considering future agricultural intensification, timely interventions are needed to ensure the livelihood and well-being of millions of small- and medium-scale farmers that rely on low storage, hard rock aquifers in the semi-arid regions of the world.

Establishing and testing a catchment water footprint framework to inform sustainable irrigation water use for an aquifer under stress

Future water scarcities in the face of an increasing population, climate change and the unsustainable use of aquifers will present major challenges to global food production. The ability of water footprints (WFs) to inform water resource management at catchment-scale was investigated on the Steenkoppies Aquifer, South Africa. Yields based on cropping areas were multiplied with season-specific WFs for each crop to determine blue and green water consumption by agriculture. Precipitation and evapotranspiration of natural vegetation and other uses of blue water were included with the agricultural WFs to compare water availability and consumption in a catchment sustainability assessment. This information was used to derive a water balance and develop a catchment WF framework that gave important insights into the hydrology of the aquifer through a simplified method. This method, which requires the monitoring of only a few key variables, including rainfall, agricultural production, WFs of natural vegetation and other blue water flows, can be applied to inform the sustainability of catchment scale water use (as opposed to more complex hydrological studies). Results indicate that current irrigation on the Steenkoppies Aquifer is unsustainable. This is confirmed by declining groundwater levels, and suggests that there should be no further expansion of irrigated agriculture on the Steenkoppies Aquifer. Discrepancies between in- and outflows of water in the catchment indicated that further development of the WF approach is required to improve understanding of the geohydrology of the aquifer and to set and meet sustainability targets for the aquifer. It is envisaged that this ‘working’ framework can be applied to other water-stressed aquifers around the world.

GIS-Based Spatial and Temporal Investigation of Groundwater Level Fluctuations Under Rice-Wheat Ecosystem over Haryana

ABSTRACT Groundwater irrigation is the most predominant method used across India and about 50% of the total irrigated area is dependent on it. The state of Haryana has witnessed a spectacular increase in agricultural production in the last few decades, and is largely dependent on groundwater for irrigation. Groundwater mining for irrigation has become a reality in the state over the years as the number of tube wells has increased from 0.02 million in 1966 to 0.73 million in 2012, showing alarming signs of over-exploitation. The impact of increased groundwater irrigation on groundwater levels has not been studied both spatially and temporally. Therefore, this study has been undertaken to investigate the groundwater level fluctuations in the state using geographical information system (GIS) from the groundwater level data of 893 observation wells obtained from Groundwater Cell, Department of Agriculture, Government of Haryana, Panchkula, for the period 2004-12. Many researchers have applied GIS to reveal the spatial and temporal structure of groundwater level fluctuation and as a management and decision tool. The analysis of results indicated a mix of negative and positive trends in the groundwater levels. However, the negative trends were much more pronounced than positive ones. Groundwater level in the state ranged between 0.16 to 65.97 m from the ground surface and per cent area with groundwater level depth more than 10 meter (critical category) was about 56% in 2004 and has increased to 64% by 2012. The average annual decline in groundwater level was observed to be above 32 cm/year, with the strongest decline (108.9 cm/year) in Kurukshetra district.

US Water Regulations and India's Water Challenges

India's current population is 1.3 billion, almost one‐fifth of the world's population. The economy of India is the seventh‐largest in the world (on the basis of nominal gross domestic product) and the third‐largest (by purchasing power parity). India's economy grew at a rate of 7.6% in 2015 ‐ 2016 and is expected to grow 8.0% in 2016 ‐ 2017. Despite this economic growth, India is facing water resource challenges such as cleaning its water bodies, providing safe drinking water, protecting public health, and reversing declining groundwater levels. Many of these water issues are similar to what the United States encountered several decades ago.

Identification of the influencing factors on groundwater drought and depletion in north-western Bangladesh

Groundwater drought is a specific type of hydrological drought that concerns groundwater bodies. It may have a significant adverse effect on the socio-economic, agricultural, and environmental conditions. Investigating the effect of different climatic and anthropogenic factors on groundwater drought provides essential information for sustainable planning and management of (ground) water resources. The aim of this study is to identify the influencing factors on groundwater drought in north-western Bangladesh, to understand the forcing mechanisms. A multi-step methodology is proposed to achieve this objective. The standardised precipitation index (SPI) and reconnaissance drought index (RDI) have been used to quantify the aggregated deficit between precipitation and the evaporative demand of the atmosphere, i.e. meteorological drought. The influence of land-cover patterns on the groundwater drought has been identified by calculating spatially distributed groundwater recharge as a function of land cover. Groundwater drought is defined by a threshold method. The results show that the evapotranspiration and rainfall deficits are determining meteorological drought, which shows a direct relation with groundwater recharge deficits. Land-cover change has a small effect on groundwater recharge but does not seem to be the main cause of groundwater-level decline (depletion) in the study area. The groundwater depth and groundwater-level deficit (drought) is continuously increasing with little correlation to meteorological drought or recharge anomalies. Overexploitation of groundwater for irrigation seems to be the main cause of groundwater-level decline in the study area. Efficient irrigation management is essential to reduce the growing pressure on groundwater resources and ensure sustainable water management.

Developing groundwater conservation zone of unconfined aquifer in Semarang, Indonesia

The increasing exploitation of groundwater affects some environmental problems such as declining groundwater levels and its quality, land subsidence, seawater intrusion, and flooding in Semarang. Nowadays, groundwater protection and its management programs are crucial in Semarang due to raising several environmental problems. Semarang has two different morphologies i.e. lowlands, and coastal plains are in the north while hilly areas spread in the south. The main objective of this research is delineating groundwater conservation zone based on its current status of groundwater both in quantity and quality. The hydrogeology mapping was performed by measuring water table as well as physical parameters of groundwater samples from both dug wells and springs. Results conduct that the groundwater depth is approximately 0.03 m to 34 m below ground surface and flowing from the south to the north. The pH varies between 4.63 and 8.95. The Dissolved Oxygen is around 0.06-3.37 mg/L while salinity has yielded up to 3,600 mg/L in the north of Semarang. The EC value is in a range from 39-6,370 µS/cm. Based on lowering the water table, deterioration of groundwater quality, and land subsidence there are four groundwater conservation zones, i.e. secure, vulnerable, critical, and damaged zones.

Examining the Relationship between Drought Indices and Groundwater Levels

Thorough characterization of the response of finite water resources to climatic factors is essential for water monitoring and management. In this study, groundwater level data from U.S. Geological Survey Ground-Water Climate Response Network wells were used to analyze the relationship between selected drought indices and groundwater level fluctuation. The drought episodes included in this study were selected using climate division level drought indices. Indices included the Palmer Drought Severity Index, Palmer Hydrological Drought Index, and Standardized Precipitation Index (SPI-6, 9, 12, 24). Precipitation and the average temperature were also used. SPI-24 was found to correlate best with groundwater levels during drought. For 17 out of 32 wells, SPI-24 showed the best correlation amongst all of the indices. For 12 out of 32 wells, SPI-24 showed correlation coefficients of −0.6 or stronger; and for other wells, reasonably good correlation was demonstrated. The statistical significance of SPI-24 in predicting groundwater level was also tested. The correlation of average monthly groundwater levels with SPI-24 does not change much throughout the timeframe, for all of the studied wells. The duration of drought also had a significant correlation with the decline of groundwater levels. This study illustrates how drought indices can be used for a rapid assessment of drought impact on groundwater level.

Model-Based Deficit Irrigation of Maize in Kansas

Abstract. Maize is the dominant irrigated crop in Kansas. In recent years, as a result of declining groundwater levels in the Ogallala aquifer and diminished well capacities, farmers are turning to deficit irrigation strategies. This study demonstrates the potential of model-based optimization for determining adequate soil water depletion levels. CERES-Maize was used as surrogate crop, while the AquaCrop model was used in an optimization procedure that determined the optimal water depletion levels. A multi-objective optimization framework was used to determine several combinations of optimal water depletion levels based on ten years of historical weather, and these combinations were tested using an additional 50 years of historical weather. The results show that, although imperfect modeling and weather fluctuations caused the actual yield to be different from the target yield, the fluctuations around the multi-year averages were not significantly larger when testing the irrigation schedule with the CERES-Maize model than when testing it with the AquaCrop model that had been used to develop the irrigation schedule. Keywords: AquaCrop, Center-pivot irrigation, CERES-Maize, Multi-objective optimization.

Land subsidence due to groundwater withdrawal in Arak plain, Markazi province, Iran

With current trends of groundwater exploitation, the plains of Iran have been facing numerous problems, where subsidence is considered as the foremost obstacle. In the present study, the principle aim was to analyze the level of groundwater and induced subsidence effects in different regions of Arak plain from 2002 to 2008. Arak plain located in Meyghan Lake basin is subjected to subsidence process as a result of the declining groundwater levels. Monthly variations of groundwater levels were plotted using ArcGIS software. The results indicated declining water levels especially in Meyghan Lake than the Arak plains, resulting up to 36 m of drop in the groundwater levels of marginal areas in the plains during these years.

Iran’s Socio-economic Drought: Challenges of a Water-Bankrupt Nation

Iran is currently experiencing serious water problems. Frequent droughts coupled with over-abstraction of surface and groundwater through a large network of hydraulic infrastructure and deep wells have escalated the nation’s water situation to a critical level. This is evidenced by drying lakes, rivers and wetlands, declining groundwater levels, land subsidence, water quality degradation, soil erosion, desertification and more frequent dust storms. This paper overviews the major drivers of Iran’s water problems. It is argued that while climatic changes and economic sanctions are commonly blamed as the main drivers of water problems, Iran is mainly suffering from a socio-economic drought—i.e. “water bankruptcy,” where water demand exceeds the natural water supply. In theory, this problem can be resolved by re-establishing the balance between water supply and demand through developing additional sources of water supply and implementing aggressive water demand reduction plans. Nevertheless, the current structure of the water governance system in Iran and the absence of a comprehensive understanding of the root causes of the problem leave minimal hope of developing sustainable solutions to Iran’s unprecedented water problems.

Dams, Drought and Water Shortage in Today’s Iran

Iran has a long history of effective and sustainable water resource management under arid and semi-arid conditions. However, today the country is faced with serious challenges in the water sector, including rising water demand and shortages, declining groundwater levels, deteriorating water quality, and increasing threats to the environment and various ecosystems. If these issues persist, tragedy will be the inevitable result. Over the last three decades tremendous efforts have been made to supply water, primarily through an extensive program of development, with dam building at the forefront. This paper offers an introduction to the different factors and elements influencing the water balance in today’s Iran and presents a perspective on the trend of dam building in recent times.

Evaluation of water-limited cropping systems in a semi-arid climate using DSSAT-CSM

Water is the major factor limiting crop production in western Kansas due to declining groundwater levels in the Ogallala aquifer resulting from withdrawals for irrigation exceeding recharge rates coupled with erratic semi-arid rainfall. Study objectives were to assess yield and water productivity of water limited cropping systems in western Kansas using DSSAT-CSM (Decision Support System for Agrotechnology Transfer Cropping Systems Model). The cropping systems evaluated included continuous (corn, wheat, and grain sorghum) and rotation (corn-wheat, corn-wheat-grain sorghum, and corn-wheat-grain sorghum-corn). Results showed that the model adequately reproduced measured days to flowering and maturity as well as yield and aboveground biomass of all three crops. Crop rotation improved water productivity of corn. Under deficit irrigation, corn in rotation produced higher yields, crop water productivity, and irrigation water use efficiency compared to continuous corn, implying that crop rotation is a better option under limited well capacities. Under full irrigation, yield and water productivity of continuous wheat were lower than wheat in rotation. In contrast, continuous wheat yields under deficit irrigation were better than under crop rotation. Deficit irrigation substantially improved irrigation water use efficiency of grain sorghum under both continuous and crop rotations. Long–term average grain sorghum yields under rotation were higher than those of continuous grain sorghum. Indicating grain sorghum should be grown in rotation under deficit irrigation. This research did not simulate the impacts of pests, weeds and diseases, hail and freeze damage on crop yield. However, the study identifies cropping systems that are more likely to produce highest water productivity under semi-arid climate similar to that in western Kansas.

Bi-decadal groundwater level trends in a semi-arid south indian region: Declines, causes and management

Study region Three districts in crystalline aquifer region of semi-arid south India. Study focus India, world’s largest groundwater user (250 billion m3 yr−1) has been reported to experience declining groundwater levels. However, the statistical significance of the decline has not been analyzed to separate human effects from natural variability. Trends in groundwater levels in three administrative districts of south India were analyzed and explained through changes in irrigation, rainfall, and agricultural power subsidy. New hydrological insights for the region Contrary to common perception of widespread groundwater declines only 22–36% of the wells showed statistically significant declines. The use of well depth during dry well periods may slightly underestimate the number of declining wells (by 1%) and rate of decline. Increase in groundwater irrigated area combined with rainfall and power subsidy policy, were the main causative factors for the decline. Groundwater decline after implementation of free-electricity policy in 2004 confirmed the nexus between power subsidy and groundwater. These declines are likely to worsen due to future well drillings. Trends in other regions with similar hydro-geologic conditions need to be analyzed to verify groundwater declines and its linkages with power subsidy. Once established, reforms in power subsidy and well permit policy along with conversion to efficient micro–irrigation may be needed to maintain or enhance groundwater availability in the crystalline aquifer region of India (240 million ha).

Impact of intensive groundwater exploitation on an unprotected covered karst aquifer: a case study in Kermanshah Province, western Iran

Islam Abad region, located in the southwestern of Kermanshah Province, is a karst region where over-exploitation from the deep karst water resources has directly affected the water balance of the whole area. Using a combination of geophysical investigations and analysis of well log data and other relevant hydrogeological studies, we looked for the actual relationship between over-exploitation from deep-water wells, penetrated into the covered karst aquifer, and the drying out of some of the main karst springs throughout the study area. In total, 20 piezometric wells and 4 main karst springs have been chosen for groundwater monitoring network. By integrating GIS processing system and a classical water balance method together with hydrogeology and hydrogeochemical spatial maps, critical zones of human impacts on groundwater resources, made by water extraction for agricultural demand, were identified. Results show that water balance in the Islam Abad basin is in clear disequilibrium, since 2.15 mcm of water depletes from the main aquifers of the study area, annually. This volume of water shortage has resulted in a 7 m groundwater level decline in the last decade, which caused both drying out and reduction in discharge rate of some of the main karst springs throughout the study area. Depths of penetration of deep-water wells into the covered karst aquifer vary from 1 to 93 m. Hydrogeochemical evaluations, including ion relations and hydrogeochemical diagrams, show interactions between karst and alluvium aquifers. Results showed a broad connection between these two resources and, therefore any pressure on alluvium aquifer will affect the karst aquifer, especially by excessive deep-water wells drilling in mutual alluvial and covered karst aquifers.

Unanswered questions for implementation of the Sustainable Groundwater Management Act

Outlook Unanswered questions for implementation of the Sustainable Groundwater Management Act Michael Kiparsky, Director, Wheeler Water Institute, Center for Law, Energy & the Environment, UC Berkeley School of Law A rig drills a new well in Merced County. In the foreground is a pressure relief structure for subsurface water pipes. Groundwater accounts for between one-third and two-thirds of California’s water use in a given year and serves as a lifeline when surface water runs low during drought. In part because of California’s historical lack of groundwater use regulation, this crucial resource is threatened. In some areas, declining groundwater levels have caused the land surface to subside at a rate of more than one inch per month, damaging roads, canals and pipelines. Falling water tables are driving a well-drilling race that threatens farms, communi- ties and ecosystems. To address the problem of chronic groundwa- ter overdraft, SGMA, adopted in 2014, declares a state policy of managing groundwater sustainably, with sustainability defined as avoiding six specific undesirable results. These are “significant and unreasonable” (1) lowering of groundwater levels, (2) reduction in groundwater storage, (3) seawater intrusion, (4) water quality degradation, (5) land subsidence and (6) impacts on beneficial uses of interconnected surface waters. In concept, this forward-thinking framing aligns the requirements of the law with the im- pacts of unsustainable groundwater use and the actions needed to address those impacts. To accomplish these objectives, SGMA relies primarily on local control, with an enforcement backstop provided by the State Water Resources Control Board. New local entities called groundwa- ter sustainability agencies (GSAs) will do the bulk of the work of implementing SGMA by developing, implementing and updating groundwater sustain- ability plans (GSPs). A GSP provides the template for achieving sustainable groundwater manage- ment in a GSA’s jurisdiction within 20 years. GSAs must be formed by 2017 and GSPs completed by 2020 or 2022. http://calag.ucanr.edu • OCTOBER–DECEMBER 2016 165 Leigh Bernacchi C alifornia is grappling with the implications of the Sustainable Groundwater Management Act (SGMA), a visionary and potentially revolutionary law that could profoundly change the way water is managed in the state. The nature of the revolution, however, is not yet clear. Whether and how SGMA achieves its goals hinges on open questions about its implementation.

Groundwater recharge modelling in semi-arid regions; a case study of El Khairat alluvial plain (Tunisia)

A regional decline of groundwater level is observed in the El Khairat plain. The increase in extraction is probably the main cause. The evaluation of groundwater recharge is an important step for the sustainable management of groundwater resources. A conceptual ‘rainfall–runoff’ model is developed to assess the El Khairat aquifer recharge. The model calibration aimed to reproduce the measured surface runoff and the observed water table level. Only 17% of rainfall recharges the aquifer, and the rest is mostly lost to evaporation. Analysis of the groundwater-level hydrographs indicated different hydraulic responses of the aquifer following rainfall events. Upstream, the water table rise is fast with a large amplitude, whereas a dampened response is observed downstream.

Rural drinking water issues in India’s drought-prone area: a case of Maharashtra state

Obtaining sufficient drinking water with acceptable quality under circumstances of lack, such as droughts, is a challenge in drought-prone areas of India. This study examined rural drinking water availability issues during a recent drought (2012) through 22 focus group discussions (FGDs) in a drought-prone catchment of India. Also, a small chemical water quality study was undertaken to evaluate the suitability of water for drinking purpose based on Bureau of Indian Standards (BIS). The drought that began in 2011 and further deteriorated water supplies in 2012 caused a rapid decline in reservoir storages and groundwater levels that led, in turn, to the failure of the public water supply systems in the Upper Bhima Catchment. Dried up and low-yield dug wells and borewells, tanker water deliveries from remote sources, untimely water deliveries, and degraded water quality were the major problems identified in the FGDs. In addition to severe drinking water scarcity during drought, the quality of the drinking water was found to be a major problem, and it apparently was neglected by local governments and users. Severe contamination of the drinking water with nitrate-nitrogen, ammonium-nitrogen, and chlorides was found in the analyzed drinking water samples. Hence, in addition to the water scarcity, the results of this study point to an immediate need to investigate the problem of contaminated drinking water sources while designing relief measures for drought-prone areas of India.

Modeling of groundwater draft based on satellite-derived crop acreage estimation over an arid region of northwest India

Over-exploitation of groundwater for agricultural crops puts stress on the sustainability of natural resources in the arid region of Rajasthan state, India. Hydrogeological study of groundwater levels of the study area during the pre-monsoon (May to June), post-monsoon (October to November) and post-irrigation (February to March) seasons of 2004–2005 to 2011–2012 shows a steady decline of groundwater levels at the rate of 1.28–1.68 m/year, mainly due to excessive groundwater draft for irrigation. Due to the low density of the groundwater observation-well network in the study area, assessment of groundwater draft, and thus groundwater resource management, becomes a difficult task. To overcome the situation, a linear groundwater draft model (LGDM) has been developed based on the empirical relationship between satellite-derived crop acreage and the observed groundwater draft for the year 2003–2004. The model has been validated for a decade, during three year-long intervals (2005–2006, 2008–2009 and 2011–2012) using groundwater draft, estimated through a discharge factor method. Further, the estimated draft was validated through observed pumping data from random sampled villages (2011–2012). The results suggest that the developed LGDM model provides a good alternative to the estimation of groundwater draft based on satellite-based crop area in the absence of groundwater observation wells in arid regions of northwest India.