Depletion Of Groundwater Resources Research Articles

Challenges of sustainable groundwater management for large scale irrigation under changing climate in Lower Ganga River basin in India

Groundwater based irrigation is one of the key factors for rapid agricultural development in India. Therefore, understanding the sustainability of irrigation water management is utmost important for agriculture. This study investigated the sustainability of groundwater based irrigation by identifying recent (1996–2017) trend in groundwater depth using Mann-Kendall (MK) test or Modified MK and Sen's slope analysis. This study also explored the relationships of groundwater depth with rainfall and irrigated areas in lower Ganga River basin in India with an area 195,601 km2. Results showed that almost 81.78%, 66.22%, 74.38% and 66.79% wells for pre-monsoon, monsoon, post-monsoon and winter seasons respectively showed increasing trends in groundwater depth. The rapid increasing trend (slope: 8.95–104.46 cm/year) in monsoon season indicates shallow groundwater resource depletion and groundwater abstraction exceeds the groundwater recharge. Moreover, dry seasons increasing trends infer that shallow pumps will not functioning in future as a result irrigation cost will increase. Although irrigated areas remain almost same (1997–2014), decreasing rainfall along with abstraction of groundwater during dry season is primarily identified as main driving force for groundwater depletion. Further study is necessary to characterize the groundwater depletion. Planned water management is urgent for ensuring sustainable irrigation water management.

Exploring farmers’ perceptions about their depleting groundwater resources using path analysis: implications for groundwater overdraft and income diversification

Iran is among the world’s top five groundwater exploiters and, similar to many countries in the world, aquifers in Iran have been rapidly depleted over the past decades primarily as a result of groundwater use by farmers. This research was conducted to explore whether the perceptions of pistachio growers in Rafsanjan Plain, Iran (a global center for pistachio production), on the depleting groundwater resources have led to the conservation of the resources and/or income diversification. In addition, the association between these perceptions and factors representing knowledge of growers was examined. To this end, two path models were developed and tested using path analysis and logistic regression. The results indicate that growers who had more pessimistic perceptions of the groundwater resources in Rafsanjan were more likely to increase groundwater extraction; however, these growers were also more likely to seek external employment (income diversification). The final path models suggest attitudes toward groundwater conservation were the most important determinants of pumping behavior, while perceptions of the state of the groundwater were the most important determinants of income diversification. Whether Iranian policies to increase awareness of falling water tables could succeed in securing water conservation would depend on the ‘balance’ of these two forces—an increase in pumping with increased pessimism or a potential decrease in pumping through income diversification. The paper concludes with a discussion on the implications of the results for interventions aimed at changing not only the groundwater users’ decisions about groundwater use, but also their decisions about income diversification.

Assessment and monitoring of groundwater quality in semi –arid region

The depletion of groundwater resources threatens water security around the world and it is of prime concern. Minimization of the impact of unhealthy drinking water requires monitoring of contaminants and awareness to all stake holders. The work is aimed at developing a Water Quality Index (WQI) to assess and report water quality to policy makers and stake holders for comprehensive planning. This new WQI method assigns individual weights to each sample point under consideration, along with wholesome weights, to account for the relative risk of each contaminant. Water quality is determined for pre and post monsoon seasons. Spatial distribution of water quality is used to estimate the probable impact on affected population. A case study was carried out to validate the method. For this purpose, a total of 163 wells (covering an area of 30,623 square km.) were sampled in a semi-arid region in North India, during pre and post monsoon seasons. Sixteen physico-chemical parameters were measured and six parameters were deemed highly critical due to their coverage and associated health risk. Against the general belief, a rise in the number of wells with permissible limits of Chloride, Nitrite, Fluoride and TDS is observed after the monsoon. The WQI determined by the procedure indicates that only 47% and 59% of the local populace has access to groundwater of acceptable quality during pre and post monsoon seasons respectively.

Assessing Agriculture Conservation Practice Impacts on Groundwater Levels at Watershed Scale

Over the last several decades, increased groundwater usage by agriculture with a consequence of groundwater resource depletion has motivated the discussion of sustainability of groundwater resource. In this study, to investigate the impacts of agricultural best management practices (BMPs) on groundwater level, two kinds of conservation practices and five scenarios of tail water recovery pond and crop rotation were simulated by various groundwater recharge and pumping plans in Soil and Water Assessment Tool (SWAT) and MODFLOW models in an agriculture watershed in Mississippi, U.S.. The calibrated and validated ground water model indicated coefficient of determination (R2) of 0.81 and Nash–Sutcliffe model efficiency coefficient (NSE) of 0.79 respectively. The results from this study showed that the groundwater recharge changed with irrigation plans and surface hydrological impact of management practices. In addition, it determined that tail water recovery pond could help mitigate groundwater depletion. The groundwater recharge due to continuous corn crop scenario was 7% higher in average than that of the continuous soybean. Non-growing season groundwater recharge may be critical for groundwater recovery. The average groundwater level was increased continuous corn scenario by 15%, continuous soybean by 13%, and corn-soybean by 14% as compare to the baseline scenario with rice planted. Results of this study can be helpful for planning on how various BMPs impact on groundwater.

Nalyzing the effectiveness of Water Conservation Fee amidst growing water scarcity in India


 
 
 Water scarcity has become a significant issue in India, causing the central government to take various measures in addressing the issue through conservation efforts. This includes revising existing and formulating new regulation guidelines, creating awareness about conservation methods, and identifying critical and over-critical areas. In 2018, the concerned ministry endorsed the suggestion to levy Water Conservation Fee (WCF) on industrial, commercial, domestic and agricultural users of water in a bid to conserve depleting groundwater resources. The following paper aims to analyze the effectiveness of WCF, highlighting two major impediments to its success.
 
 

Assessment of the sustainability of different cropping systems under three irrigation strategies in the North China Plain under climate change

The annual double-cropping system of winter wheat and summer maize requires a large amount of irrigation which has led to the rapid depletion of groundwater resources in the North China Plain (NCP). Alternate cropping systems and limited irrigation strategies should be developed for the purposes of maintaining sustainable groundwater use now and in the future. In this study, the water use and crop production of seven cropping systems under three irrigation strategies were assessed using the Agricultural Production Systems SIMulator (APSIM) during 1987–2017 as a baseline and in 2040, 2060, and 2080 under climate change conditions at a typical site in the NCP. The APSIM was calibrated and validated using field experimental data collected during 2007–2016. The seven cropping systems included the current double annual cropping system (2C/1Y) and six other reduced cropping-intensity systems with either three crops every two years (3C/2Y) or one crop per year (1C/1Y). The three irrigation strategies were full irrigation (FI), minimum irrigation (MI, only one irrigation at sowing for seedling establishment) and critical stage irrigation (CI, adding one more irrigation at the critical stage based on MI). The results showed that under current growing conditions, sustainable groundwater use could be achieved with 2C/1Y under MI, 3C/2Y and 1C/1Y under FI. However, the annual yield production was reduced by 9–22% under 3C/2Y and 54–79% under 1C/1Y compared with that under 2C/1Y. The results indicated that 2C/1Y was a better choice for crop production under similar water use. The simulated yield for future scenarios was lower than that during the baseline period; and the reduction rate varied from 2 to 11% under FI; 6–9% under CI; and 10–21% under MI, suggesting that crop production would be more negatively affected under water-limited conditions than that under full water supply condition. The annual water use of the reduced cropping systems was projected to increase because of relative high soil evaporation during the fallow period (Ef). Water use efficiency (WUE) was reduced partly due to the increased Ef. The traditional 2C/1Y under MI had the potential to sustain the groundwater balance in the region and concurrently resulted in higher grain production and WUE than that of the systems with reduced cropping intensity, both now and under climate change, and therefore, this system should be prioritized in this region.

Numerical analysis of physical barriers systems efficiency in controlling saltwater intrusion in coastal aquifers.

Saltwater intrusion (SWI) increases salinity of aquifers and depletion of groundwater resources in coastal aquifers. Different methods have been used to control SWI in the coastal aquifers in order to protect groundwater. In this paper, applicability of physical subsurface barriers (PSB) methods to control SWI in the Biscayne aquifer in Florida, USA, is studied. Numerical models have been developed to study and compare performance of two types of the PSB namely cutoff wall and subsurface dam for SWI control. The developed numerical models have been verified through simulation of benchmark examples and then have been used to simulate a semi-hypothetical case study relying on hydrogeological data measured in the Biscayne aquifer. Different scenarios of barriers depths, locations, and permeability have been analyzed. The results indicated that the PSB can effectively control the intrusion of saline into coastal aquifers. However, cutoff wall gave higher retardation than sub-surface dams.

The Market and Common-Pool Resource Problem: Surface Water Trading and Groundwater Depletion in California

This paper examines how a surface water market affects the performance of a groundwater basin that is in open access. The market only solves the groundwater over-extraction problem when pumping costs are high, while market failure arises when the common pool resource (CPR) problem is severe. I build a theoretical model to analyze the agricultural water use in California Central Valley. The model establishes the link between the efficacy of surface water market and the farmers' crop choices in response to water supply changes. I use a micro level crop choice data to test the theory and find that the farmers rarely react to short-term water supply variations. In particular, crop acreage does not fall during droughts. This implies that pumping costs are low and sellers replace whatever amount they sell with groundwater. Therefore, surface water trade is inefficient when taking into account the depletion of groundwater resource and should be curtailed until the CPR problem is addressed.

Predicting groundwater potential zones in Upper Thal Doab, Indus Basin through integrated use of RS and GIS techniques and groundwater flow modeling

In Pakistan, groundwater contributes about 40% in total water resources of the country and is considered a great source of fresh water which plays vibrant role in sustainability of irrigated agriculture. It is critical to safe and properly manage groundwater resources of the country for sustainable use. To ascertain groundwater potential areas and current status of the aquifer in the Upper Thal Doab, a part of Indus Basin in the Punjab Plain, an integrated approach of remote sensing (RS), Geographic Information System (GIS), and groundwater modeling has been adopted. Different input data sets like, geology, geomorphology, rainfall, land use/land cover, elevation, and drainage were overlaid and weighted to prepare groundwater potential zones map. The results classify the groundwater potential zones into three categories: good, moderate, and poor. The results demonstrate that about 12% of the study area is designated as good, 27% moderate, and 61% as poor. The groundwater modeling of the area was also carried out to find the current status of the aquifer, favorable sites for groundwater and predict future scenarios. The steady-state model was calibrated with the hydrological conditions of 1984 when the hydraulic heads were appeared to be in equilibrium condition. Transient simulations were calibrated for six stress periods with varying lengths commencing from 1985 to 2025. The mass balance analysis for transient model shows that the total outflows gradually increases than inflows from 1991 onwards due to increase in water extraction through water wells. The results demand to conduct periodic studies of the area to monitor the groundwater resources depletion if any in due course of time for timely management and precautionary measures.

Occurrence and distribution of organic and inorganic pollutants in groundwater.

Depletion of groundwater resources and continued decline in overall groundwater quality is a cause of concern because large human population around the world uses groundwater as a source of drinking water. This paper presents a comprehensive review of studies published in the year 2018 that documented issues of groundwater pollution, sources, and distribution reported from across the world due to anthropogenic, hydroclimatogical, and natural processes. Groundwater pollution due to organic contaminants focuses particularly on pesticides, herbicides, and contaminants of emerging concern. Pollution due to inorganic pollutants such as arsenic and other heavy metals is also reviewed with particular emphasis on regions that have reported a significantly higher incidence of these pollutants in groundwater. A compilation of various studies is also included in the review paper that showed increased incidences of waterborne illnesses due to fecal and microbial contamination due to poor sanitary practices. Reviews of groundwater contaminants such as fluoride and nitrate are included to provide readers a holistic understanding of groundwater pollution problem around the world. PRACTITIONER POINTS: Groundwater pollution issues during 2018 are reviewed and documented. Occurrence of organic and inorganic pollutants in groundwater is reported. Groundwater pollution vulnerability remains a critical issue.

Identification of water use efficient wheat genotypes with high yield for regions of depleting water resources in India

Intensive cultivation of irrigated wheat in 30 m ha area is mainly causing the depletion of groundwater resources in India. This calls for urgent technological interventions to improve the water productivity of wheat for sustaining the profitability of farmers. Seventy-one genetically diverse wheat genotypes were screened for high water use efficiency (WUE) under limited soil moisture level at 60% of Cumulative Pan Evaporation (CPE) during 2015-16. Out of these best performing sixteen high WUE genotypes were shortlisted for a detailed field study during 2016-17 and 2017-18. The limited irrigation treatments were imposed through micro irrigation system for precise delivery of the estimated quantity of water to the root zone. Water use efficiency, grain yield (GY), above ground biomass (AGBM), harvest index (HI), thousand grain weight (TGW), tillers per meter square (TPM), SPAD chlorophyll meter reading (SCMR) and relative water content (RWC) were measured. Pearson correlation identified GY (r = 0.99), AGBM (r = 0.46), HI (r = 0.86), TGW (r = 0.52) and SCMR (r = 0.46) at post-anthesis as significant traits contributing to higher WUE. Tukey’s test of significance led ranking and GGE biplot analysis identified DBW 243 (2.40 kg m−3) as the best genotype for WUE. Better HI was the basis for increased WUE. The identified high WUE genotype could be a useful resource to researchers globally to develop water use efficient cultivars with high yield. Additionally, the associated traits on WUE could be used as a selection criterion in breeding wheat for limited water conditions. Adoption of superior WUE genotypes could directly reduce water consumption by 20%, further contributing to the reduced cost of cultivation (USD 42.6 ha-1) to farmers. Cultivation of identified genotypes in over 12 m ha wheat area of North Western Plains Zone of India could produce similar yields and can conserve 7728 million m3 of water year-1.

Conjunctive Water Resources Management in Densely Urbanized Karst Areas: A Study in the Sete Lagoas Region, State of Minas Gerais, Brazil

Headwater catchments store valuable resources of quality water, but their hydraulic response is difficult to assess (model) because they are usually deprived of monitoring stations, namely hydrometric stations. This issue becomes even more pertinent because headwater catchments are ideal for the practice of conjunctive water resources management involving the supply of towns with groundwater and surface water, a solution that can be used to mitigate overexploitation of groundwater resources in densely urbanized and populated areas. In this study, a stepwise approach is presented whereby, in a first stage, a gauged basin was modeled for stream flow using the JAMS J2000 framework, with the purpose to obtain calibrated hydraulic parameters and ecological simulated stream flow records. Having validated the model through a comparison of simulated and measured flows, the simulated record was adjusted to the scale of an ungauged sub-basin, based on a new run of JAMS J2000 using the same hydraulic parameters. At this stage, a second validation of modeled data was accomplished through comparison of the downscaled flow rates with discharge rates assessed by field measurements of flow velocity and water column height. The modeled basin was a portion of Jequitiba River basin, while the enclosed sub-basin was the Marinheiro catchment (state of Minas Gerais, Brazil). The latter is a peri-urban watershed located in the vicinity of Sete Lagoas town, a densely urbanized and populated area. This town uses 15.5 hm3 year−1 of karst groundwater for public water supply, but the renewable resources were estimated to be 6.3 hm3 year−1. The impairment between abstraction and renewable resources lasts for decades, and for that reason the town experiences systemic water table declines and sinkhole development. The present study claims that the storage of quality water in the Marinheiro catchment, in a dam reservoir, would help alleviate the depletion of groundwater resources in the karst aquifer because this catchment could deliver 4.73 hm3 year−1 of quality surface water to the municipality without endangering ecologic flows. The construction of a small dam at the outlet of Marinheiro catchment could also improve aquifer recharge. Presently, the annual recharge in this catchment approaches 1.47 hm3 but could be much larger if the small dam was installed in the water course and the captured stream water managed properly.

Evaluation of Groundwater Vulnerability to Contamination in Coimbatore District

Groundwater usage in the world is widely reported to increase because of the uncertainties attached with the availability of surface water. Groundwater resources are looked upon as the alternate source of freshwater on account of its widespread and continuous availability in proximity to the point of use or living place, less vulnerability to contamination and low cost of extraction in both urban and rural area of developed and developing countries of the world. Such a scenario has led to the degradation and depletion of groundwater resources in many parts of the world. The study area, Coimbatore district, is a rapidly urbanizing and industrializing city in the southern part of India which relies upon the groundwater resources for meeting the agricultural, industrial and domestic requirements. In view of this evaluation of groundwater resources and an understanding of the vulnerability of the aquifer to contamination become essential for the effective management of groundwater resources. The vulnerability of the groundwater to contamination is assessed using DRASTIC and Pesticide DRASTIC index in the GIS environment. The study showed that the high vulnerability areas are characterized by shallow water table of less than 4 m, gentle topography, sandy loam soils, thinner vadose zone and underlying geologic formations with well-developed fissures and fractures.

Quantifying irrigation adaptation strategies in response to stakeholder-driven groundwater management in the US High Plains Aquifer

Irrigation enhances agricultural yields and stabilizes farmer incomes, but overexploitation has depleted groundwater resources around the globe. Strategies to address this sustainability challenge differ widely. Socio-ecological systems research suggests that management of common pool resources like groundwater would benefit from localized approaches that combine self-organization along with active monitoring. In 2012, the US state of Kansas established a Local Enhanced Management Area (LEMA) program, empowering farmers to work with local and state officials to develop five-year, enforceable groundwater conservation programs. Here, we assessed the efficacy of the first LEMA implemented from 2013 to 2017 using a causal impact methodology based on Bayesian structural time series that is new to agrohydrology. Compared to control scenarios, we found that the LEMA reduced water use by 31% over the five-year period, with early indications of stabilizing groundwater levels. Three main conservation strategies can lead to reduced water use: (1) reducing irrigated area, (2) reducing irrigation amount applied to existing crops through improved efficiency, and/or (3) switching to crops that require less water. To partition water savings among these strategies, we combined satellite-derived irrigated areas and crop type maps with well records. We found that farmers were able to largely maintain irrigated area and achieved the majority of pumping reductions (72%) from improvements in irrigation efficiency, followed by expansion of crops with lower water demand (19%). The results of this analysis demonstrate that conservation programs that are irrigator-driven with regulatory oversight can provide a path toward sustainability in stressed aquifers.

Identifying Climate-Induced Groundwater Depletion in GRACE Observations

Depletion of groundwater resources has been identified in numerous global aquifers, suggesting that extractions have exceeded natural recharge rates in critically important global freshwater supplies. Groundwater depletion has been ascribed to groundwater pumping, often ignoring influences of direct and indirect consequences of climate variability. Here, we explore relations between natural and human drivers and spatiotemporal changes in groundwater storage derived from the Gravity Recovery and Climate Experiment (GRACE) satellites using regression procedures and dominance analysis. Changes in groundwater storage are found to be influenced by direct climate variability, whereby groundwater recharge and precipitation exhibited greater influence as compared to groundwater pumping. Weak influence of groundwater pumping may be explained, in part, by quasi-equilibrium aquifer conditions that occur after “long-time” pumping, while precipitation and groundwater recharge records capture groundwater responses linked to climate-induced groundwater depletion. Evaluating groundwater response to climate variability is critical given the reliance of groundwater resources to satisfy water demands and impending changes in climate variability that may threaten future water availability.

Diverse drivers of unsustainable groundwater extraction behaviour operate in an unregulated water scarce region

Depletion of groundwater resources is of increasing concern in many parts of the world; however, farmers' perceptions of resource status and the role these have in influencing decisions about groundwater use are rarely considered and even more rarely analysed. This paper investigates the links between farmers' perceptions of resource condition and drivers of groundwater decline and patterns of groundwater use in the semi-arid highland region of Balochistan, Pakistan. Key factors associated with groundwater over-exploitation in this region, identified by farmers, include: high returns from irrigated fruit and vegetable cultivation; drought; mass installation of tubewells; inefficient irrigation practices; government policies and subsidies that promote groundwater development; and lack of effective groundwater governance. Critically, while a majority of farmers in this study believe that groundwater is a limited resource, there is little evidence to indicate that this then leads to sustainable groundwater use decision making within these communities. Without effective intervention, groundwater resources in this region will potentially suffer the consequences of human behaviour associated with the use of common pool resources identified in Hardin's (1968) seminal ‘Tragedy of the Commons’ paper. This study exemplifies the importance to the future of rural communities in water scarce regions of effective governance, regulations and economic incentives for sustainable water management.

Spatial distribution of physico-chemical parameters for groundwater quality evaluation in a part of Satluj River Basin, India

Abstract The rising population, contamination and mismanagement of groundwater worldwide require sustainable management techniques and strategies to prevent misuse of groundwater resources especially in the semi-arid regions of the world. The aim of the present study is to assess the distribution of contaminants in groundwater at a spatial level by using a geostatistical method, namely ordinary kriging. For this, a physico-chemical parameter data set at 14 sampling locations for a period over 25 years was assessed. Three semi-variogram models, namely exponential, Gaussian and spherical, fitted well for the data set and were cross-validated using predictive statistics. Based on nugget/sill ratio, which characterizes the overall spatial dependence of water quality parameters, it was observed that, apart from nitrate, all the other parameters showed moderate to weak spatial dependence (i.e. total hardness), indicating significant influence of urbanization, fertilization and industrialization. Spatial distribution maps of all the parameters were generated. Concentration of most of the parameters reported high values in the northern region, while silicon dioxide and potassium recorded high values in the southern and central regions of the study area respectively. The study highlighted the depleting groundwater resources in various regions of the study area, indicating that the groundwater quality is in a declining state.

Evaluation of national and regional groundwater resources under climate change scenarios using a GIS-based water budget procedure

The present study investigates the impact of climate change on the availability of groundwater resources in Italy and in Campania region (Southern Italy). A 20-year average from 1996 to 2015 of annual water budget components (namely total precipitation, actual evapotranspiration, surface runoff and aquifer recharge) has been evaluated over a 1-km resolution grid and have been projected considering four climate change scenarios (from the Fifth Assessment Report of the United Nations Intergovernmental Panel on Climate Change) and three different future 20-year time periods (2020–2039, 2040–2059 and 2080–2099). The groundwater balance has been carried out on a yearly basis using the “Nationwide GIS-based regular gridded hydrological water budget” procedure, which has been developed by the Italian National Institute for Environmental Protection and Research (ISPRA). The different scenarios of groundwater resources have been compared and matched to the 20-year average of latest historical values related to the period 1996–2015, leading to interesting considerations about the future depletion of groundwater resources. Nationwide results have been compared with those of Campania region, in order to underline the significant differences of climate change impact on groundwater resources at local scale, especially in a typical Mediterranean climate where groundwater resources represent the main source of water for human needs.

Water management problems and solutions in a residential community of Al-Mafraq city, Jordan

Abstract This study aims to investigate existing water management problems and potential solutions in the Al-Mafraq Governorate of Jordan, and to examine public awareness of water demand management at the household level. A questionnaire survey captured residents' perceptions of water quantity and quality. Results showed that 71% of respondents find the water pumped from the public system to be insufficient, and 40.9% find that water laws and regulations are implemented ineffectively. The study also showed that 85% of respondents are dependent upon groundwater wells, and 42.5% of respondents have suffered water contamination. Water quality is degraded due to pollution caused by solid waste and liquids, and salinity is increased due to the over-pumping and depletion of groundwater resources. The study recommends that the government incentivize residents to harvest water to deal with water shortages, religious motivations be explored in water conservation efforts, and water authorities should repair or replace old pipelines.

EFFECT OF WASTEWATER AND FERTILIZER APPLICATION ON CALCAREOUS SOIL AND FOOD CROPS IN BORG EL ARAB – EGYPT

This paper summarizes the available information on the pollution of groundwater and irrigation canals from anthropogenic sources (sewage effluences and industrial waste water, and intensive fertilization) in northwestern Egypt Borg El Arab that leading to contamination of the soil-plant-animal. Excessive applications of fertilizers to field and vegetable crops lead to nitrate and phosphate contamination of groundwater and irrigation canals. In certain situations, nitrates exceed the dangerous level of 10 mg N/L. Industrial effluents, released without anytreatment to sewage drains, contain potentially toxic elements with a concentrations that are several fold higherthan those in domestic sewage water and exceed the maximum permissible limits for their disposal onto agricultural lands. The mean concentrations of Pb, Co, Cd and Ni in sewage water were, respectively 21,133, 700, and 2200 times higher than those in artesian water. The recommendation possible mitigation options for water pollution. There is an urgent need to effectively enforce regulations for the release of industrial effluents pertaining to primary, secondary and tertiary treatments. Educating farmers and public at large about the consequences of non-overkill Nitrogen fertilizer, pumping out shallow polluted water for drinking and domestic purposes, depleting groundwater resources, etc., is desirable