Freshwater Withdrawals Research Articles

Performance of flue gas quench and its influence on biomass fueled CHP

For biomass/waste fueled power plants, stricter regulations require a further reduction of the negative impacts on the environment caused by the release of pollutants and withdrawal of fresh water externally. Flue gas quench (FGQ) is playing an important role in biomass or waste fueled combined heat and power (CHP) plants, as it can link the flue gas (FG) cleaning, energy recovery and wastewater treatment. Enhancing water evaporation can benefit the concentrating of pollutant in the quench water; however, when FG condenser (FGC) is not in use, it results in a large consumption of fresh water. In order to deeply understand the operation of FGQ, a mathematic model was developed and validated against the measurements. Based on simulation results key parameters affecting FGQ have been identified, such as the flow rate and temperature of recycling water and the moisture content of FG. A guideline about how to reduce the discharge of wastewater to the external and the withdrawal of external water can be proposed. The mathematic model was also implemented into an ASPEN Plus model about a CHP plant to assess the impacts of FGQ on CHP. Results show that when the FGC was running, increasing the flow rate and decreasing the temperature of recycling water can result in a lower total energy efficiency.

Global socio-hydrology: An overview of virtual water use by the world economy from source of exploitation to sink of final consumption

To reflect a key aspect of global socio-hydrology, this paper explores global virtual water use from source of exploitation to sink of final consumption via interregional trades within the world economy as reflected by world input-output database for 2014. An embodiment accounting model is developed, which takes full account of virtual water feedbacks related to primary inputs. Global total trade volume of virtual water is estimated to be in magnitude around 30% of the global direct freshwater withdrawal. Moreover, it is revealed that global virtual water transfer in intermediate trade is in magnitude around 1.4 times that in final trade. In intermediate trade of virtual water, China, Japan and the United Kingdom turn out to be the three leading net importers, while India, Russia and the United States are revealed as the leading net exporters. In final trade of virtual water, the United States, Japan and Russia are the major net importers, in contrast to China, India and Mexico as the leading net exporters. Trade connections and imbalances of major economies in terms of virtual water are quantified and analyzed. Two new indicators in terms of water self-sufficiency rate by source and that by sink are devised. It is found that around 40% of the use of China’s freshwater withdrawal finally sinks into foreign economies while only 20% of China’s virtual water use originates from other regions. With regard to Germany, Canada and France, they behave like active pumps driving vast virtual water inflows and outflows, demonstrating their high involvement in the global supply chain in terms of virtual water. With the increasingly frequent virtual water transfer within the world economy, nations and regions ought to assess their behaviors in intermediate and final trades of virtual water for sustainable use of freshwater resources.

Global Aid in the Water Sector: A Descriptive Analysis of International Development Effectiveness

This study analyzes the intent and effectiveness of international development aid through a content/trend analysis of over 42,000 aid projects in the water supply and sanitation sector. The water sector is a vital and understudied component of international development that is rife with internal contradictions. On the one hand, access to water is rapidly increasing cross-nationally, but over 700 million still lack improved access to water. On the other hand, renewable freshwater resources per capita are rapidly decreasing, and annual freshwater withdrawals are steadily increasing. These concurrent issues lead to water stress and decreased freshwater sustainability, which in turn affects global political, ecological, and health issues. To address these issues, national governments and multinational aid agencies have been lending to the water supply and sanitation sector since 1950. This study assesses the trends in international aid over the past 65 years for their intent and effectiveness in solving global water and development issues. The results have implications for the development effectiveness of nations’ and organizations’ aid and calls for social scientists to investigate well-being and environmental impacts simultaneously in all sectors of development.

The relative aggregate footprint of electricity generation technologies in the European Union (EU): A system of systems approach

Decarbonizing electricity risks unintended consequences for other environmental resources. The European Union’s (EU) Member States (MSs) embarked on a decarbonization and renewables deployment program aware of this risk. However, uncertainty remains around which technologies are best suited to the nexus of resources affected. In this study, we illustrate the benefits of using the Relative Aggregate Footprint (RAF) concept to evaluate energy technology alternatives. The RAF is an indicator based on a System of Systems approach that assesses technologies along multiple performance criteria, takes account of performance uncertainty, adjusts criteria importance according to local resource availabilities, and makes the evaluation robust to differing notions of optimality to determine the desirability of technologies. We evaluated 11 electricity generation technologies by cost, carbon, water and land footprint. Assuming equal weightings of the four criteria, we found nuclear, geothermal, and onshore wind to generally have the lowest RAF. We then calculated the MS-specific RAF’s by weighing each criterion based on the local availability of the respective resource: 1) gross domestic product per capita, 2) carbon emissions per capita, 3) freshwater withdrawals as a share of renewable freshwater, and 4) land availability per capita. By analyzing variances between MSs’ RAFs we highlighted how differences in resource availability generate trade-offs for EU electricity decarbonization policies.

A Comprehensive Hydrodynamics-Salinity-pH Model for Analyzing the Effects of Freshwater Withdrawals in Calcasieu Lake and Surrounding Water Systems

The study is a continuation of the authors' previous works on hydrodynamics and sediment transport modeling for Calcasieu Lake area (located in southwest Louisiana) (Zhang, N., Zheng, Z. C., and Yadagiri, S., 2011, “A Hydrodynamic Simulation for the Circulation and Transport in Coastal Watersheds,” Comput. Fluids, 47(1), pp. 178–88; Zhang, N., Kee, D., and Li, P., 2013, “Investigation of the Impacts of Gulf Sediments on Calcasieu Ship Channel and Surrounding Water Systems,” Comput. Fluids, 77, pp. 125–133; Yadav, P. K., Thapa, S., Han, X., Richmond, C., and Zhang, N., 2015, “Investigation of the Effects of Wetland Vegetation on Coastal Flood Reduction Using Hydrodynamic Simulation,” ASME Paper No. AJKFluids2015-3044). The major purposes of the study are: (1) to demonstrate the new model features and validate the model results, (2) to disclose the effects of Gulf Intracoastal Waterway (GIWW) and determine the boundary conditions for GIWW in the model, and (3) to use the model to analyze the effects of excessive freshwater withdrawals on the changes of hydrodynamics and salinity in the Calcasieu Lake system. Several new model features were added to the existing model framework, including the extension of modeling domain, vegetation model, salinity transport model, and pH calculation. Measurement data from NOAA and USGS are used as boundary conditions for the model. Simulation results were compared with measurement data from NOAA, USGS and other sources for validation. Due to lack of measured data for GIWW in the target area, the effect of GIWW flow conditions on the modeling results was investigated and appropriate GIWW boundary condition was determined based on numerical tests. Numerous petrochemical plants in the area use tremendous amount of fresh surface water. Recent industry expansions may further increase the demands of freshwater withdrawals. One of the purposes of the study is to use developed model to test and analyze the effects of increased freshwater withdrawal from Calcasieu River at the north boundary of the study area on the hydrodynamics and salinity in the downstream Calcasieu Lake system.

Precision conservation meets precision agriculture: A case study from southern Ontario

Meeting future food demands for 9 billion people in the next 30 years will require either agricultural expansion or intensification to increase production. However, agriculture is already a major driver of biodiversity loss, as well as freshwater withdrawals, nutrient inputs, and greenhouse gasses, among other pressing environmental issues. In this paper, we look for solutions to this production-conservation challenge at the subfield scale. We use precision agriculture yield data from three farms in Southern Ontario and convert them into “profit maps” that show which regions of a field have management costs that exceed the market value of the commodities produced. We analyse the profit of three farms over time and identify areas that consistently show low or negative profit and thus constitute a compelling case for taking these areas out of production. We find, for example, that up to 14% of farmland can result in money loss and even more than 50% of the land might still not meet minimum revenue expectations. Further, we assess the economic feasibility of conservation strategies on these set-aside lands and find that investing in environmental benefits (even minimally) can often times be inexpensive when compared with economic losses due to failed harvests. We argue that profit mapping can serve as a management tool for farmers that will allow them to identify optimal crop areas, optimize nutrient inputs, plan for ecological intensification, and avoid economic loss all while providing ecosystem services at the local scale.

Seawater and water footprint in different cropping systems: A chicory (Cichorium intybus L.) case study

The world population is forecast to rise, needing a remarkable increase in food production. As agriculture is among the most water-demanding sectors, such augmentation could negatively affect water resource. Thus actions should be taken both to improve the water efficiency of current cropping systems and to seek alternative water sources for agriculture. The improvement of water efficiency in agriculture has been long investigated. Soilless culture, especially hydroponics, is characterized by a particular attention to the water resource. A different approach is represented by alternative water sources, i.e. seawater, considered as a realistic option in agriculture, either desalinized or blended with freshwater. This study compared the water footprint (WF) of the chicory crop (Cichorium intybus L. var. silvestre) grown in the following cropping systems: a conventional soilless system using freshwater (blue-hydroponics); conventional soil cultivation (blue-pots and open field); a soilless system integrated with a 10% share of seawater (sea-hydroponics); pots irrigated with a 10% share of seawater (sea-pots).By adding seawater to irrigation, we also introduced the "seawater footprint" concept, discussing the environmental implications of the provenience of the irrigation water. Our results showed a significant reduction in WF in both blue-hydroponic and sea-hydroponic (i.e. 64% and 75%, respectively) systems compared to soil cultivation with sea-hydroponics providing the best result in terms of biomass production and water saving. By contrast, sea-pots' performances in terms of WF were significantly lower (at P ≤ 0.05), with an increase of WF of 104% compared to open field cultivation. As the seawater share led to very different results in the two systems, it can be speculated that seawater is not the only reason for the sea-pots' poor performance. Nevertheless, the combination of poor results in terms of both biomass production and water saving and the detrimental effects of salinity on soil make the option of soil cropping with seawater unrealistic. However a controlled use of seawater in soilless culture could reduce, without any negative environmental concern, the freshwater withdrawal dedicated to food production. Moreover, our results also suggested a higher salt tolerance in hydroponic conditions compared to soil cultivation for the tested crop.

Breaking the spell

Electricity production has traditionally required extensive water use, so growing economies such as China are expected to increase their freshwater withdrawal and consumption to meet growing electricity demand. Research shows, however, that through restructuring the electricity sector and increasing efficiency, China may have broken this coupling.

Decoupling between water use and thermoelectric power generation growth in China

As energy and water are fundamentally intertwined, understanding the spatial and temporal evolution of thermoelectric water use and water stress is important for both sustainable energy development and water resource management. Here we compile high-resolution time-series (2000–2015) of water withdrawal and consumption inventories for China’s thermoelectric power sector to identify the driving forces behind changing water use patterns, and reveal the spatial distribution of thermoelectric water stress. We show that freshwater withdrawal has been decoupled from thermoelectric power generation growth at the national level due to the increased adoption of air-cooling and seawater-cooling technologies and advanced large generating units as well as water use efficiency improvements in this period. Nevertheless, the construction of large coal-fired power generation hubs has increased water stress in many arid and water-scarce catchments in northwestern regions of China. The westward development of the power industry necessitates water-withdrawal caps and the integration of water risk analysis into energy planning. Decoupling resource use from energy production is critical for sustainable development. Here, researchers show a decoupling between water use and electricity generation growth in China, accompanied by changing spatial distribution of associated water stress.

High-Pressure Reverse Osmosis for Energy-Efficient Hypersaline Brine Desalination: Current Status, Design Considerations, and Research Needs

Water scarcity, expected to become more widespread in the coming years, demands renewed attention to freshwater protection and management. Critical to this effort are the minimization of freshwater withdrawals and elimination of wastewater discharge, both of which can be achieved via zero liquid discharge (ZLD), an aggressive wastewater management approach. Because of the high energetic cost of thermal desalination, ZLD is particularly challenging for high-salinity wastewaters. In this review, we discuss the potential of high-pressure reverse osmosis (HPRO) (i.e., reverse osmosis operated at a hydraulic pressure greater than ∼100 bar) to efficiently desalinate hypersaline brines. We first discuss the inherent energy efficiency of membrane processes compared to that of conventional thermal processes for brine desalination. We then highlight the opportunity of HPRO to reduce energy requirements for desalination of key high-salinity industrial wastewaters. The current state of membrane materials and processe...

Disclosing water-energy-economics nexus in shale gas development

Shale gas has gained importance in the energy landscape in recent decades. However, its development has raised environmental concerns, especially, those associated with water management. Thus, the assessment of water management aspects, which inevitably impact the economic aspects, is crucial in evaluating the merits of any project exploiting this energy source. This paper provides a review of the economic and environmental implications of shale gas development around the world. Furthermore, to demonstrate the interplay between the various technical, environmental and economic factors in concrete terms, we report on a specific set of case studies conducted using an integrated decision-support tool that has been implemented to model and optimize shale gas development projects. The case study results confirm that the gas breakeven price decreases with expansion in scale of the shale gas development, i.e. increasing the number of well-pads in the system. However, scale also increases the options for water re-use and recycle in drilling and fracturing operations, which can result in lower freshwater withdrawal intensity. Moreover, under water scarcity scenarios, the choice of well-pad designs that are inherently less water intensive was found to be more cost-effective than water re-use or/and recycle strategies at reducing net freshwater demand. Similar trends were observed when the impact of wastewater quality, i.e. total dissolved solids concentration, on the optimal development strategy of shale gas plays was investigated. The results of these case studies reveal that greater efforts are needed at characterizing freshwater availability and wastewater quality for the evaluation of both the economic and environmental aspects of shale gas development.

River Discharge and Saltwater Intrusion Level Study of Yangtze River Estuary, China

The Yangtze River Estuary (YRE) is the largest estuary in China, with three-order bifurcations and four outlets into the sea. In recent years, issues of saltwater intrusions have received increased attention due to the increased levels and frequencies of the intrusions. The saltwater intrusions into the YRE resulting from river discharges were investigated in this study based on river discharge levels at the Datong station. A hydrodynamic and salinity transport model (MIKE21) was used to quantify the influences of the river discharges on the saltwater intrusions in the YRE. The model was effectively validated through observational data of the tidal and salinity levels. The 25%, 50% and 70% frequencies of the river discharges during the dry seasons were determined to be 18,112, 16,331 and 14,832 m3/s, respectively. A multi-year averaged river discharge of 27,856 m3/s was used to simulate the salinity level changes resulting from the different river discharges. The results revealed the following: (1) the salinity of the South Branch (SB) was distributed as “high–low–high”; and the changes in the salinity levels were greatly affected by the river discharges. A strong correlation was found between the salinity and flow in the North Branch (NB) and SB of between 0.917 and 1; (2) the changes in the river discharges had major impacts on the changes in the salinity levels in the SB. When the runoff was 27,856 m3/s, the salinity excessive area rate (the ratio between salinity excessive area (>0.45‰) and the SB area) less than 10%. However, when the river discharges were reduced to 16,331 m3/s, the salinity excessive area rate is more than 50%; (3) As the river discharges decreased, the amplification line (0.2‰) also rapidly decreased, and the amplification lines (0.45‰, 2‰) increased. At points far from the river’s entrance, the effects of the runoff were observed to be weakened, such as the amplification lines gradually becoming reduced; (4) the changes in the river discharges were observed to have significant impacts on the freshwater reservoir water withdrawal. When the river discharges were maintained at 27,856 m3/s, the salinity of the Baogang, Chenhang, and Qingcaosha Reservoirs remained below 0.45‰. The salinity levels of the four reservoir locations examined in this study were found to exceed the Chinese drinking water standard (0.45‰) for more than 23 days in the 14,832 m3/s river discharge scenario, which negatively affected the drinking water of the population living near the YRE.

Water Use in the United States Energy System: A National Assessment and Unit Process Inventory of Water Consumption and Withdrawals.

The United States (US) energy system is a large water user, but the nature of that use is poorly understood. To support resource comanagement and fill this noted gap in the literature, this work presents detailed estimates for US-based water consumption and withdrawals for the US energy system as of 2014, including both intensity values and the first known estimate of total water consumption and withdrawal by the US energy system. We address 126 unit processes, many of which are new additions to the literature, differentiated among 17 fuel cycles, five life cycle stages, three water source categories, and four levels of water quality. Overall coverage is about 99% of commercially traded US primary energy consumption with detailed energy flows by unit process. Energy-related water consumption, or water removed from its source and not directly returned, accounts for about 10% of both total and freshwater US water consumption. Major consumers include biofuels (via irrigation), oil (via deep well injection, usually of nonfreshwater), and hydropower (via evaporation and seepage). The US energy system also accounts for about 40% of both total and freshwater US water withdrawals, i.e., water removed from its source regardless of fate. About 70% of withdrawals are associated with the once-through cooling systems of approximately 300 steam cycle power plants that produce about 25% of US electricity.

Linking the water-energy-food nexus and sustainable development indicators for the Mediterranean region

Water use and agricultural practices in the Mediterranean area are unsustainable. The situation is worsened by the increased frequency of droughts and floods, as well as desertification and soil depletion, associated with climate change. The aim of Partnership for Research and Innovation in the Mediterranean Area (PRIMA) is to foster an integrated programme of sustainable food production and water provision in the framework of the water-energy-food nexus. A monitoring tool developed under PRIMA is based on the Sustainable Development Goals, two of which are specifically dedicated to food security (SDG 2) and sustainable management of water (SDG 6).The 12 indicators that have been chosen to be monitored in the Mediterranean area are: Multidimensional Poverty Index (MPI); population overweight (%); land use (%); GHG emissions (total and AFOLU)(tCO2e); cereal yield (kg/ha); agriculture value added (US$/worker); fertilizer consumption (kg/haarable land); crop water productivity (kg/m3); annual freshwater withdrawal for agriculture (%); population served using with safely managed water service (rural, %); population served using with safely managed sanitation (rural, %); amount of agricultural residues used for energy purposes (t). Datasets for these indicators are collected by international bodies such as the World Bank, WHO, FAO and UNFCCC; recent series are available for almost all Mediterranean countries and are constantly updated. The aim of the proposed monitoring tool is to keep track of the impact generated in by PRIMA research and innovation projects Mediterranean countries.

Synergistic management of flowback and produced waters during the upstream shale gas operations driven by non-cooperative stakeholders

Shale gas has been denoted as one of alternative energy sources for meeting future energy demands and received global attention, especially with aid of technological advances in horizontal drilling and hydraulic fracturing. This study focuses specially on synergistic optimization of the Marcellus shale-gas-water supply chains with consideration of economics and pollutants mitigation through a mixed-integer bi-level programming model. This model could account for conflicting objectives and interactions between different stakeholders. Operational decisions regarding well drilling schedule, production planning, freshwater withdrawals, wastewater disposal, and infrastructure expansion would be provided for both leader and follower in a sequential manner. Moreover, comparative analyses among the bi-level model and the two single-level models disclose that the bi-level decisions would increase nearly 8.6% of shale gas production, 12.3% of economic benefits, 8.0% of water consumption, and 4.5% of pollutants discharge as compared with the environmentally-aggressive policies. By contrary, the bi-level decisions would lead to 8.5% decrease of shale gas production, 6.1% decrease of economic benefits, 7.3% decrease of water usage, and 6.0% decrease of pollutants discharge when compared with the economically-aggressive solutions. These findings could assist the stakeholders in resolving of conflicts among pollutants reduction, economic performance, and water supply security.

Effects of Annual Droughts on Fish Communities in Mississippi Sound Estuaries

The Mississippi coastal region has two major rivers and four smaller rivers influencing the estuaries that make up the Mississippi Sound. The islands off Mississippi create a barrier which allows the area to be a widespread, productive estuarine region. With such a dependence on discharge from the drainages, it is important to understand the effect of salinity regimes on fish communities. Drought conditions in other regions have been shown to dramatically change the fish community structure. We used the long running Interjurisdictional Fisheries Program database (2006–2014) within Mississippi state waters and compared yearly fish communities between drought and non-drought years. Non-metric Multidimensional Scaling (nMDS), Analysis of Similarity (ANOSIM), and Indicator Species Analysis (ISA) were used to compare drought and non-drought conditions in the Mississippi Sound. During 2006 and 2007, which were identified as drought years by the Palmer Drought Severity Index (PDSI), differences in fish community structure were identified and compared to non-drought years (2008–2009 and 2011–2014). The ISA identified a total of eight species that were significantly influenced by drought years. Of the eight species, the abundance of seven species significantly decreased while the abundance of one species significantly increased. With an increasing human population in central and south Mississippi, pressure on freshwater resources is likely to increase, resulting in possible changes in the fish community dynamics of the Mississippi Sound. Understanding the influence of decreased river discharges will assist managers in determining the impacts of freshwater withdrawals during base flow periods.

The UN World Water Development Report 2016, Water and Jobs: A Critical Review

The UN World Water Development Report 2016, <i>Water and Jobs</i>: A Critical Review

Well Salinization Risk and Effects of Baltic Sea Level Rise on the Groundwater-Dependent Island of Öland, Sweden

In this study, we estimate baseline conditions in terms of the current risk of well salinization on the Baltic Sea island of Öland, Sweden, and assess the effects of future sea level rise on the land area, infrastructure and cultural values. We use a multicriterion geographical information systems (GIS) approach. Geomorphological and physical parameters affect the risk of saltwater intrusion into freshwater aquifers, including their hydrology, geomorphology, and climatology; the spatial distribution of the current risk of salinization is mapped in this study. In the event of a future 2 m sea level rise, a total land area of 67 km2 will be inundated on Öland, corresponding to approximately 5% of the island’s land surface. Inundation includes urban areas, nature reserves, and animal protection areas, implying the loss of environmental and socioeconomic values. A future 2 m sea level rise will also cause direct inundation of 3% of all wells on the island. Currently, 17.5% of all wells are at a high risk of becoming saltwater contaminated. More generally, the present results add evidence showing a relatively high vulnerability of major Baltic Sea islands and their infrastructure to future sea level rise. The approach used here and related results, including salinization risk maps, may prove useful for decision-makers in the planning of infrastructure. Drilling of new wells could for instance preferably be done in areas with identified lower risk-index values, which would facilitate an overall higher freshwater withdrawal in the interest of the entire island.

Intelligent Irrigation Management System

It is widely known that water resources are decreasing around the world. Rapid urbanization, population growth, industries and the expansion of agriculture are increasing demand for freshwater. In most countries, including Algeria, irrigation is the largest consumer of water, with about 70% of all freshwater withdrawals being used for irrigation. Therefore, it can be said that solving the problem of water scarcity is based on the adjustment of irrigation. The aim of this paper is to shed light on the irrigation systems, how they can be applied, and what are their benefits. With the adoption of solar energy to feed the system; this energy source is strongly available in arid zones.

Life Cycle Assessment of Groundwater Supply System in a Hyper-arid Region of India

This paper addresses the life cycle assessment (LCA) of groundwater supply system in hyper-arid region of Bikaner block in the state of Rajasthan, India. The key objective of this research is to address potential environmental impacts of groundwater extraction for irrigation purpose and sustainable management of groundwater in water scarce regions. To assess the impact of groundwater extraction, the functional unit of the study has been taken as one kiloliter of freshwater withdrawal using submersible water pumps for irrigation purpose. The primary data for the water withdrawal and energy consumption are collected through semi-structured interview conducted among the end users in the region. The energy and material flow modelling of the ground water system have been developed using Umberto NXT Universal and Ecoinvent dataset v3.0. The environmental impact assessment is carried out using well-known ReCiPe method. It is observed from the analysis that copper used in equipment of ground water supply system and energy consumption for ground water extraction generate significant impacts to the environment. The results thus obtained are very helpful in decision making and to formulate a suitable ground water development/withdrawal policy while dealing with different environmental issues of groundwater management.