Water

31 pages, 10607 KiB

Open AccessEditor’s ChoiceArticle

Spatial Data Management and Numerical Modelling: Demonstrating the Application of the QGIS-Integrated FREEWAT Platform at 13 Case Studies for Tackling Groundwater Resource Management

by Giovanna De Filippis, Christos Pouliaris, Daniel Kahuda, Teodora Alexandra Vasile, Valentina Adriana Manea, Florian Zaun, Björn Panteleit, Filiz Dadaser-Celik, Pio Positano, Marco Saulo Nannucci, Mykhailo Grodzynskyi, Andres Marandi, Manuel Sapiano, Irena Kopač, Andreas Kallioras, Massimiliano Cannata, Youssef Filiali-Meknassi, Laura Foglia, Iacopo Borsi and Rudy Rossetto

Water 2020, 12(1), 41; https://doi.org/10.3390/w12010041 - 20 Dec 2019

Cited by 22 | Viewed by 9091

Abstract

Because of the spatial nature of groundwater-related data and their time component, effective groundwater management requires the application of methods pertaining to the Information and Communication Technologies sector, such as spatial data management and distributed numerical modelling. The objective of this paper is [...] Read more.

Because of the spatial nature of groundwater-related data and their time component, effective groundwater management requires the application of methods pertaining to the Information and Communication Technologies sector, such as spatial data management and distributed numerical modelling. The objective of this paper is to demonstrate the effectiveness of the QGIS-integrated FREEWAT platform and an approach combining spatial data management and numerical models to target groundwater management issues. FREEWAT is a free and open source platform integrated in a Geographic Information System environment and embedding tools for pre- and post-processing of spatial data and integrating numerical codes for the simulation of the hydrological cycle, with a main focus on groundwater. To this aim, this paper briefly presents the FREEWAT platform, introduces the FREEWAT approach, and showcases 13 case studies in European and non-European countries where the FREEWAT platform was applied. Application of the FREEWAT platform to real-world case studies is presented for targeting management of coastal aquifers, ground- and surface-water interaction, climate change impacts, management of transboundary aquifers, rural water management and protection of groundwater-dependent ecosystems. In this sense, compared to other existing software suites, FREEWAT allows data analysis and visualization to accomplish each step of the modelling workflow, i.e., from data analytics, to conceptual model definition, to numerical modelling and reporting of results. The presented experiences demonstrate that improved access to data and the portability of models and models’ results can help to promote water sustainability from the local- to the basin-scale. Furthermore, FREEWAT may represent a valuable tool to target the objective of increasing the capabilities of public authorities and private companies to manage groundwater resources by means of up-to-date, robust, well-documented and reliable software, without entailing the need of costly licensing, nowadays seldom affordable by public water authorities. Based on the strengths highlighted, the FREEWAT platform is a powerful tool for groundwater resources management, and for data collection, sharing, implementation and comparison of scenarios, for supporting planning and decision-making. Full article

(This article belongs to the Section Water Resources Management, Policy and Governance)

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11 pages, 4286 KiB

Open AccessEditor’s ChoiceCommunication

Design of a Smart System for Rapid Bacterial Test

by Rajshree Patil, Saurabh Levin, Samuel Rajkumar and Tahmina Ajmal

Water 2020, 12(1), 15; https://doi.org/10.3390/w12010015 - 19 Dec 2019

Cited by 2 | Viewed by 4398

Abstract

In this article, we present our initial findings to support the design of an advanced field test to detect bacterial contamination in water samples. The system combines the use of image processing and neural networks to detect an early presence of bacterial activity. [...] Read more.

In this article, we present our initial findings to support the design of an advanced field test to detect bacterial contamination in water samples. The system combines the use of image processing and neural networks to detect an early presence of bacterial activity. We present here a proof of concept with some tests results. Our initial findings are very promising and indicate detection of viable bacterial cells within a period of 2 h. To the authors’ knowledge this is the first attempt to quantify viable bacterial cells in a water sample using cell splitting. We also present a detailed design of the complete system that uses the time lapse images from a microscope to complete the design of a neural network based smart system. Full article

(This article belongs to the Special Issue Technological Eco-Innovations for the Quality Control and the Decontamination of Polluted Waters and Soils)

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30 pages, 466 KiB

Open AccessEditor’s ChoiceReview

Performance of Anammox Processes for Wastewater Treatment: A Critical Review on Effects of Operational Conditions and Environmental Stresses

by Sunja Cho, Cicilia Kambey and Van Khanh Nguyen

Water 2020, 12(1), 20; https://doi.org/10.3390/w12010020 - 19 Dec 2019

Cited by 152 | Viewed by 14757

Abstract

The anaerobic ammonium oxidation (anammox) process is well-known as a low-energy consuming and eco-friendly technology for treating nitrogen-rich wastewater. Although the anammox reaction was widely investigated in terms of its application in many wastewater treatment processes, practical anammox application at the pilot and [...] Read more.

The anaerobic ammonium oxidation (anammox) process is well-known as a low-energy consuming and eco-friendly technology for treating nitrogen-rich wastewater. Although the anammox reaction was widely investigated in terms of its application in many wastewater treatment processes, practical anammox application at the pilot and industrial scales is limited because nitrogen removal efficiency and anammox activity are dependent on many operational factors such as temperature, pH, dissolved oxygen concentration, nitrogen loading, and organic matter content. In practical application, anammox bacteria are possibly vulnerable to non-essential compounds such as sulfides, toxic metal elements, alcohols, phenols, and antibiotics that are potential inhibitors owing to the complexity of the wastewater stream. This review systematically summarizes up-to-date studies on the effect of various operational factors on nitrogen removal performance along with reactor type, mode of operation (batch or continuous), and cultured anammox bacterial species. The effect of potential anammox inhibition factors such as high nitrite concentration, high salinity, sulfides, toxic metal elements, and toxic organic compounds is listed with a thorough interpretation of the synergistic and antagonistic toxicity of these inhibitors. Finally, the strategy for optimization of anammox processes for wastewater treatment is suggested, and the importance of future studies on anammox applications is indicated. Full article

(This article belongs to the Section Wastewater Treatment and Reuse)

21 pages, 7962 KiB

Open AccessEditor’s ChoiceArticle

Performance Evaluation of a Tidal Current Turbine with Bidirectional Symmetrical Foils

by Bin Guo, Dazheng Wang, Xu Zhou, Weichao Shi and Fengmei Jing

Water 2020, 12(1), 22; https://doi.org/10.3390/w12010022 - 19 Dec 2019

Cited by 17 | Viewed by 3857

Abstract

As one might expect, tidal currents in terms of ebb and flood tides are approximately bidirectional. A Horizontal Axial Tidal Turbine (HATT) with unidirectional foils has to be able to face the current directions in order to maximize current energy harvesting. There are [...] Read more.

As one might expect, tidal currents in terms of ebb and flood tides are approximately bidirectional. A Horizontal Axial Tidal Turbine (HATT) with unidirectional foils has to be able to face the current directions in order to maximize current energy harvesting. There are two regular solutions to keep a HATT always facing the direction of the flow, which are transferred from wind turbine applications. One is to yaw the turbine around the supporting structure with a yaw mechanism. The other is to reverse the blade pitch angle through 180° with a pitch-adjusting mechanism. The above solutions are not cost-effective in marine applications due to the harsh marine environment and high cost of installation and maintenance. In order to avoid the above disadvantages, a turbine with bidirectional foils is presented in this paper. A bare turbine with bidirectional foils is characterized in that it has nearly the same energy conversion capability in both tidal current directions without using the yaw or pitch mechanism. Considering the working conditions of the bidirectional turbine in which the turbine is installed on a mono-pile, the effect of the mono-pile on the turbine’s performance is evaluated in this paper, especially when the turbine is downstream of the mono-pile. The paper was focused on the evaluation of the hydrodynamic performance of the bidirectional turbine. The hydrodynamic performance of the bare bidirectional turbine without any supporting structure was evaluated based on a steady-state computational fluid dynamics (CFD) model and model tests. Performance comparison has been made between the turbine with bidirectional foils and the turbine with NACA foils. The effect of the mono-pile on the performance of the bidirectional turbine was studied by using the steady-state and the transient CFD model. The steady-state CFD model was used to evaluate the effect of the mono-pile clearance, which is the distance between the mono-pile and the turbine on the performance of the turbine. The transient CFD model was used to determine the time-dependent characteristics of the turbine, such as time-dependent power and drag coefficients. The results show that the bare bidirectional turbine has nearly the same energy conversion capability in both tidal current directions. The performance of the bidirectional turbine is inferior to the turbine with NACA foils. At the designed tip speed ratio, the power coefficient of the turbine with NACA foils is 0.4498, which increases by 1.6% compared to the 0.4338 of the bidirectional turbine. The turbine’s performance decreases due to the introduction of the mono-pile, and the closer the turbine is to the mono-pile, the greater effect on the turbine’s performance the mono-pile has. At the designed clearance of 1.5 D_S, the presence of a mono-pile decreases the peak Cp value by 1.82% and 3.17% to a value of 0.4156 and 0.4004 for the turbine located in the mono-pile upstream and downstream, respectively. The mono-pile can result in the fluctuation of the turbine’s performance. This fluctuation will detrimentally harm the life of the turbine as it will lead to increased wear and fatigue issues. Full article

(This article belongs to the Section Hydraulics and Hydrodynamics)

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21 pages, 1521 KiB

Open AccessEditor’s ChoiceArticle

An Analysis of Energy Consumption and the Use of Renewables for a Small Drinking Water Treatment Plant

by Saria Bukhary, Jacimaria Batista and Sajjad Ahmad

Water 2020, 12(1), 28; https://doi.org/10.3390/w12010028 - 19 Dec 2019

Cited by 45 | Viewed by 9844

Abstract

One of the pressing issues currently faced by the water industry is incorporating sustainability considerations into design practice and reducing the carbon emissions of energy-intensive processes. Water treatment, an indispensable step for safeguarding public health, is an energy-intensive process. The purpose of this [...] Read more.

One of the pressing issues currently faced by the water industry is incorporating sustainability considerations into design practice and reducing the carbon emissions of energy-intensive processes. Water treatment, an indispensable step for safeguarding public health, is an energy-intensive process. The purpose of this study was to analyze the energy consumption of an existing drinking water treatment plant (DWTP), then conduct a modeling study for using photovoltaics (PVs) to offset that energy consumption, and thus reduce emissions. The selected plant, located in southwestern United States, treats 0.425 m³ of groundwater per second by utilizing the processes of coagulation, filtration, and disinfection. Based on the energy consumption individually determined for each unit process (validated using the DWTP’s data), the DWTP was sized for PVs (as a modeling study). The results showed that the dependency of a DWTP on the traditional electric grid could be greatly reduced by the use of PVs. The largest consumption of energy was associated with the pumping operations, corresponding to 150.6 Wh m⁻³ for the booster pumps to covey water to the storage tanks, while the energy intensity of the water treatment units was found to be 3.1 Wh m⁻³. A PV system with a 1.5 MW capacity with battery storage (30 MWh) was found to have a positive net present value and a levelized cost of electricity of 3.1 cents kWh⁻¹. A net reduction in the carbon emissions was found as 950 and 570 metric tons of CO₂-eq year⁻¹ due to the PV-based design, with and without battery storage, respectively. Full article

(This article belongs to the Special Issue Integrated Assessment of the Water–Energy–Land Nexus)

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14 pages, 4044 KiB

Open AccessEditor’s ChoiceArticle

Removal of Microcystis aeruginosa through the Combined Effect of Plasma Discharge and Hydrodynamic Cavitation

by Blahoslav Maršálek, Eliška Maršálková, Klára Odehnalová, František Pochylý, Pavel Rudolf, Pavel Stahel, Jozef Rahel, Jan Čech, Simona Fialová and Štěpán Zezulka

Water 2020, 12(1), 8; https://doi.org/10.3390/w12010008 - 18 Dec 2019

Cited by 30 | Viewed by 5433

Abstract

Cyanobacterial water blooms represent toxicological, ecological and technological problems around the globe. When present in raw water used for drinking water production, one of the best strategies is to remove the cyanobacterial biomass gently before treatment, avoiding cell destruction and cyanotoxins release. This [...] Read more.

Cyanobacterial water blooms represent toxicological, ecological and technological problems around the globe. When present in raw water used for drinking water production, one of the best strategies is to remove the cyanobacterial biomass gently before treatment, avoiding cell destruction and cyanotoxins release. This paper presents a new method for the removal of cyanobacterial biomass during drinking water pre-treatment that combines hydrodynamic cavitation with cold plasma discharge. Cavitation produces press stress that causes Microcystis gas vesicles to collapse. The cyanobacteria then sink, allowing for removal by sedimentation. The cyanobacteria showed no signs of revitalisation, even after seven days under optimal conditions with nutrient enrichment, as photosynthetic activity is negatively affected by hydrogen peroxide produced by plasma burnt in the cavitation cloud. Using this method, cyanobacteria can be removed in a single treatment, with no increase in microcystin concentration. This novel technology appears to be highly promising for continual treatment of raw water inflow in drinking water treatment plants and will also be of interest to those wishing to treat surface waters without the use of algaecides. Full article

(This article belongs to the Section Wastewater Treatment and Reuse)

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14 pages, 1871 KiB

Open AccessEditor’s ChoiceArticle

Solar Septic Tank: Next Generation Sequencing Reveals Effluent Microbial Community Composition as a Useful Index of System Performance

by Stephanie Connelly, Tatchai Pussayanavin, Richard J. Randle-Boggis, Araya Wicheansan, Suparat Jampathong, Ciara Keating, Umer Z. Ijaz, Willian T. Sloan and Thammarat Koottatep

Water 2019, 11(12), 2660; https://doi.org/10.3390/w11122660 - 17 Dec 2019

Cited by 16 | Viewed by 11324

Abstract

Septic tanks are widely deployed for off-grid sewage management but are typified by poor treatment performance, discharge of polluting effluents and the requirement for frequent de-sludging. The Solar Septic Tank (SST) is a novel septic tank design that uses passive heat from the [...] Read more.

Septic tanks are widely deployed for off-grid sewage management but are typified by poor treatment performance, discharge of polluting effluents and the requirement for frequent de-sludging. The Solar Septic Tank (SST) is a novel septic tank design that uses passive heat from the sun to raise in-tank temperatures and improves solids degradation, resulting in a cleaner effluent. Treatment has been shown to exceed conventional systems, however, the underlying biology driving treatment in the system is poorly understood. We used next generation sequencing (Illumina Miseq (San Diego, CA, USA), V4 region 16S DNA) to monitor the microbiology in the sludge and effluent of two mature systems, a conventional septic tank and an SST, during four months of routine operation in Bangkok, Thailand, and evaluated the ecology against a suite of operating and performance data collected during the same time period. Significant differences were observed between the microbiome of the sludge and effluent in each system and the dominant taxa in each appeared persistent over time. Furthermore, variation in the microbial community composition in the system effluents correlated with effluent water quality and treatment performance parameters, including the removal of chemical and biochemical oxygen demand and the concentration of fecal and total coliforms in the effluent. Thus, we propose that a wide-scale survey of the biology underlying decentralised biotechnologies for sewage treatment such as the SST could be conducted by sampling system effluent rather than sampling sludge. This is advantageous as accessing sludge during sampling is both hazardous and potentially disruptive to the anaerobic methanogenic consortia underlying treatment in the systems. Full article

(This article belongs to the Section Wastewater Treatment and Reuse)

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15 pages, 7911 KiB

Open AccessEditor’s ChoiceArticle

Field Testing of Porous Pavement Performance on Runoff and Temperature Control in Taipei City

by Yung-Yun Cheng, Shang-Lien Lo, Chia-Chun Ho, Jen-Yang Lin and Shaw L. Yu

Water 2019, 11(12), 2635; https://doi.org/10.3390/w11122635 - 13 Dec 2019

Cited by 46 | Viewed by 5982

Abstract

The Taipei University of Technology, under contract from the Taipei City Government, completed a study on porous asphalt (PA) and permeable interlocking concrete brick (PICB) pavement performance with respect to stormwater runoff reduction and surface temperature mitigation. Additionally, the variation of infiltration rates [...] Read more.

The Taipei University of Technology, under contract from the Taipei City Government, completed a study on porous asphalt (PA) and permeable interlocking concrete brick (PICB) pavement performance with respect to stormwater runoff reduction and surface temperature mitigation. Additionally, the variation of infiltration rates against time of these pavements was monitored. The results show the following: (a) Runoff peak reduction ranged from 16% for large, intense storms to 55% for small, long-duration storms. Rainfall volume reduction ranged from 16% to 77% with an average of 37.6%; (b) Infiltration rate: for PICB, it decreased by 25% to 50% over a 15-month monitoring period, but the rate at one location increased significantly after cleaning; for PA, the rate remained high at one location, but decreased by 70%–80% after 10 months at two other locations, due mainly to clogging problems; (c) Surface temperature: during storm events, porous concrete bricks had on average lower temperatures compared to regular concrete with a maximum difference of 6.6 °C; for porous asphalt the maximum drop was 3.9 °C. During dry days, both PA and PICB showed a tendency of faster temperature increase as the air temperature rose, but also faster temperature decreases as the air cooled when compared to regular pavements. On very hot days, much lower surface temperatures were observed for porous pavements (for PA: 17.0 °C and for PICB: 14.3 °C) than those for regular pavements. The results suggest that large-scale applications of porous pavements could help mitigate urban heat island impacts. Full article

(This article belongs to the Section Urban Water Management)

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11 pages, 4232 KiB

Open AccessEditor’s ChoiceArticle

Bridging the Data Gap in the Water Scarcity Footprint by Using Crop-Specific AWARE Factors

by Anne-Marie Boulay, Léo Lenoir and Alessandro Manzardo

Water 2019, 11(12), 2634; https://doi.org/10.3390/w11122634 - 13 Dec 2019

Cited by 22 | Viewed by 5820

Abstract

The assessment of the water scarcity footprint of products emerged as an important step in supporting water management strategies. Among others, the AWARE methodology was published as a consensus-based indicator to perform such an assessment at a watershed level and monthly scale. The [...] Read more.

The assessment of the water scarcity footprint of products emerged as an important step in supporting water management strategies. Among others, the AWARE methodology was published as a consensus-based indicator to perform such an assessment at a watershed level and monthly scale. The need to adopt such a detailed resolution, however, collides with the availability of data, so that general year and country-wide factors are commonly used. The objective of this study is to develop and verify the applicability of 26 crop-specific water scarcity characterization factors to help assess the water scarcity footprint when data and information availability is limited. To do so, a weighted average consumption approach was adopted, starting from local AWARE characterization factors and local crop-specific water consumption. The resulting factors, ranging from 0.19 m³/ton eq for “other perennial crop” in Brunei to 9997 m³/ton eq for “other annual crop” in Mauritania, illustrate the large variability of potential water scarcity impacts. Factors were applied to the water consumption of selected crops to assess their water scarcity footprint. The results of the study confirmed that the use of crop-specific factors is recommended as they are a better proxy of water scarcity in a region when compared to their national generic counterparts. Full article

(This article belongs to the Special Issue Water Footprint and Life Cycle Assessment: Methods and Tools for the Strategic Management of Water Related Impacts)

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15 pages, 2157 KiB

Open AccessEditor’s ChoiceArticle

Analysis and Comprehensive Evaluation of Water Use Efficiency in China

by Wenge Zhang, Xianzeng Du, Anqi Huang and Huijuan Yin

Water 2019, 11(12), 2620; https://doi.org/10.3390/w11122620 - 12 Dec 2019

Cited by 23 | Viewed by 5705

Abstract

Proper water use requires its monitoring and evaluation. An indexes system of overall water use efficiency is constructed here that covers water consumption per 10,000 yuan GDP, the coefficient of effective utilization of irrigation water, the water consumption per 10,000 yuan of industrial [...] Read more.

Proper water use requires its monitoring and evaluation. An indexes system of overall water use efficiency is constructed here that covers water consumption per 10,000 yuan GDP, the coefficient of effective utilization of irrigation water, the water consumption per 10,000 yuan of industrial value added, domestic water consumption per capita of residents, and the proportion of water function zone in key rivers and lakes complying with water-quality standards and is applied to 31 provinces in China. Efficiency is first evaluated by a projection pursuit cluster model. Multidimensional efficiency data are transformed into a low-dimensional subspace, and the accelerating genetic algorithm then optimizes the projection direction, which determines the overall efficiency index. The index reveals great variety in regional water use, with Tianjin, Beijing, Hebei, and Shandong showing highest efficiency. Shanxi, Liaoning, Shanghai, Zhejiang, Henan, Shanxi, and Gansu also use water with high efficiency. Medium efficiency occurs in Inner Mongolia, Jilin, Heilongjiang, Jiangsu, Hainan, Qinghai, Ningxia, and Low efficiency is found for Anhui, Fujian, Jiangxi, Hubei, Hunan, Guangdong, Guangxi, Chongqing, Sichuan, Guizhou, Yunnan, and Xinjiang. Tibet is the least efficient. The optimal projection direction is a* = (0.3533, 0.7014, 0.4538, 0.3315, 0.1217), and the degree of influence of agricultural irrigation efficiency, water consumption per industrial profit, water used per gross domestic product (GDP), domestic water consumption per capita of residents, and environmental water quality on the result has decreased in turn. This may aid decision making to improve overall water use efficiency across China. Full article

(This article belongs to the Section Water Use and Scarcity)

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32 pages, 12206 KiB

Open AccessEditor’s ChoiceReview

Potential Health Risks Linked to Emerging Contaminants in Major Rivers and Treated Waters

by James Kessler, Diane Dawley, Daniel Crow, Ramin Garmany and Philippe T. Georgel

Water 2019, 11(12), 2615; https://doi.org/10.3390/w11122615 - 11 Dec 2019

Cited by 9 | Viewed by 5436

Abstract

The presence of endocrine-disrupting chemicals (EDCs) in our local waterways is becoming an increasing threat to the surrounding population. These compounds and their degradation products (found in pesticides, herbicides, and plastic waste) are known to interfere with a range of biological functions from [...] Read more.

The presence of endocrine-disrupting chemicals (EDCs) in our local waterways is becoming an increasing threat to the surrounding population. These compounds and their degradation products (found in pesticides, herbicides, and plastic waste) are known to interfere with a range of biological functions from reproduction to differentiation. To better understand these effects, we used an in silico ontological pathway analysis to identify the genes affected by the most commonly detected EDCs in large river water supplies, which we grouped together based on four common functions: Organismal injuries, cell death, cancer, and behavior. In addition to EDCs, we included the opioid buprenorphine in our study, as this similar ecological threat has become increasingly detected in river water supplies. Through the identification of the pleiotropic biological effects associated with both the acute and chronic exposure to EDCs and opioids in local water supplies, our results highlight a serious health threat worthy of additional investigations with a potential emphasis on the effects linked to increased DNA damage. Full article

(This article belongs to the Special Issue Integrated Water Resources Research: Advancements in Understanding to Improve Future Sustainability)

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16 pages, 4484 KiB

Open AccessEditor’s ChoiceArticle

Membrane Fouling and Performance of Flat Ceramic Membranes in the Application of Drinking Water Purification

by Shujuan Meng, Minmin Zhang, Meng Yao, Zhuguo Qiu, Yubin Hong, Weiguang Lan, Haiping Xia and Xue Jin

Water 2019, 11(12), 2606; https://doi.org/10.3390/w11122606 - 10 Dec 2019

Cited by 38 | Viewed by 8160

Abstract

Membrane technologies have been widely applied in surface water treatment for drinking water purification. The main obstacles to the large scale application of membranes include membrane fouling, energy consumption and high investment. This study systematically investigated the performance of a hybrid system including [...] Read more.

Membrane technologies have been widely applied in surface water treatment for drinking water purification. The main obstacles to the large scale application of membranes include membrane fouling, energy consumption and high investment. This study systematically investigated the performance of a hybrid system including in-situ coagulation and membrane module. The key parameters of a membrane system, including initial flux, operation mode (intermediate or continuous, time intervals, backwashing and aeration) was comprehensively investigated. In addition, the treatment performance in terms of turbidity, organic matter removal, membrane fouling and cleaning, and the effect of coagulants, were also studied. It was found that flat ceramic membranes with in-situ coagulation for surface water treatment performed much better without aeration and frequent backwashing, which gave interesting and important implications for future applications of a flat ceramic membrane, especially in drinking water purification. The hybrid system can achieve a high-water flux of 150 L/m²·h (LMH) for 8 h operation without aeration and backwash. The removal of turbidity, UV₂₅₄ and COD can achieve 99%, 85% and 81%, respectively. The cake layer on the membrane surface formed from the coagulation flocs turned out to prevent the membrane to be exposed to organic pollutant immediately which minimized the fouling problem. In addition, the fouling layer on the membrane surface can be easily cleaned by air scouring and backwash at the end of experiments, with a water flux recovery of higher than 90%. These results in this study provided an alternative strategy for membrane fouling control and energy conservation. Full article

(This article belongs to the Special Issue Membrane Technologies and Water Treatment)

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20 pages, 1721 KiB

Open AccessEditor’s ChoiceArticle

Combining Hydrologic Analysis and Life Cycle Assessment Approaches to Evaluate Sustainability of Water Infrastructure: Uncertainty Analysis

by Hassan Tavakol-Davani, Reyhaneh Rahimi, Steven J. Burian, Christine A. Pomeroy, Brian J. McPherson and Defne Apul

Water 2019, 11(12), 2592; https://doi.org/10.3390/w11122592 - 9 Dec 2019

Cited by 13 | Viewed by 4256

Abstract

The goal of this research is identifying major sources of uncertainty of an environmentally-sustainable urban drainage infrastructure design, based on hydrologic analysis and life cycle assessment (LCA). The uncertainty analysis intends to characterize and compare relative roles of unreliability, incompleteness, technological difference, and [...] Read more.

The goal of this research is identifying major sources of uncertainty of an environmentally-sustainable urban drainage infrastructure design, based on hydrologic analysis and life cycle assessment (LCA). The uncertainty analysis intends to characterize and compare relative roles of unreliability, incompleteness, technological difference, and spatial and temporal variation in life cycle impact assessment (LCIA) data, as well as natural variability in hydrologic data. Uncertainties are analyzed using a robust Monte Carlo simulation approach, performed by High Throughput Computing (HTC) and interpreted by Morse-Scale regression models. The uncertainty analysis platform is applied to a watershed-scale LCA of rainwater harvesting systems (RWH) to control combined sewer overflows (CSOs). To consider the watershed-scale implications, RWH is simulated to serve for both the water supply and CSO control in an urban watershed in Toledo, Ohio, USA. Results suggest that, among the studied parameters, rainfall depth (as a hydrologic parameter) caused more than 86% of the uncertainty, while only 7% of the uncertainty was caused by LCIA parameters. Such an emphasis on the necessity of robust hydrologic data and associated analyses increase the reliability of LCA-based urban water infrastructure design. In addition, results suggest that such a topology-inspired model is capable of rendering an optimal RWH system capacity as a function of annual rainfall depth. Specifically, if the system could capture 1/40th of annual rainfall depth in each event from rooftops, the RWH system would be optimal and, thus, lead to minimized life cycle impacts in terms of global warming potential (GWP) and aquatic eco-toxicity (ETW). This capture depth would be around 2.1 cm for Toledo (given an 85 cm/year rainfall and 200 m² typical roof area), which could be achieved through an RWH system with 4.25 m³ capacity per household, assuming a uniform plan for the entire studied watershed. Capacities smaller than this suggested optimal value would likely result in loss of RWH potable water treatment savings and CSO control benefits, while capacities larger than the optimal would likely incur an excessive wastewater treatment burden and construction phase impacts of RWH systems. Full article

(This article belongs to the Section Urban Water Management)

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22 pages, 1374 KiB

Open AccessEditor’s ChoiceArticle

Re-Interpreting Cooperation in Transboundary Waters: Bringing Experiences from the Brahmaputra Basin

by Anamika Barua, Arundhati Deka, Vishaka Gulati, Sumit Vij, Xiawei Liao and Halla Maher Qaddumi

Water 2019, 11(12), 2589; https://doi.org/10.3390/w11122589 - 8 Dec 2019

Cited by 21 | Viewed by 11541

Abstract

Several studies have demonstrated the continuum of cooperation on transboundary rivers, but have largely focused on government to government (Track 1) cooperation and formal diplomacy. Formal arrangements like treaties, agreements, joint mechanisms, joint bodies, joint commissions (e.g., river basin organizations), etc., fall within [...] Read more.

Several studies have demonstrated the continuum of cooperation on transboundary rivers, but have largely focused on government to government (Track 1) cooperation and formal diplomacy. Formal arrangements like treaties, agreements, joint mechanisms, joint bodies, joint commissions (e.g., river basin organizations), etc., fall within the scope of transboundary waters cooperation. However, in some transboundary rivers, often due to political constraints, Track 1 cooperation might not be a feasible option. When governmental cooperation is a non-starter, effort and progress made outside the government domain through informal dialogues can play a significant role. It is therefore important to re-examine the definition of cooperation as it applies to international rivers, and potentially to broaden its scope. Such an examination raises important questions: What does international cooperation in this context actually mean? Is it formal (Track 1) cooperation related to sharing of water, data, and information only, or does it have a broader meaning? What, precisely, can be the entry point for such cooperation? Are informal transboundary dialogues and water diplomacy itself an entry point for cooperation on international rivers? This paper aimed to answer these critical questions drawing from the “Brahmaputra Dialogue” project initiated in 2013 under the South Asia Water Initiative (SAWI), which involved the four riparian countries of the Brahmaputra Basin. Several important focal points of cooperation emerged through this sustained dialogue, which went beyond sharing hydrological data or signing a basin-level treaty, broadening the definition of “cooperation”. The paper, bringing evidence from the dialogue, argues that the Brahmaputra Dialogue process has led to a broader understanding of cooperation among basin stakeholders, which could influence water resource management of the basin in the future. Full article

(This article belongs to the Special Issue Managing Water Resources in Large River Basins)

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14 pages, 3244 KiB

Open AccessEditor’s ChoiceArticle

Modeling Study of Design Flow Rates for Cascade Water Supply Systems in Residential Skyscrapers

by Yang Zhou, Eric Wai Ming Lee, Ling-Tim Wong and Kwok-Wai Mui

Water 2019, 11(12), 2580; https://doi.org/10.3390/w11122580 - 6 Dec 2019

Cited by 4 | Viewed by 9223

Abstract

Skyscrapers are common nowadays around the world, especially in cities with limited development area. In order to pump water up to the higher level of a skyscraper, a cascade water supply system has to be installed. Currently, cascade water supply systems are mainly [...] Read more.

Skyscrapers are common nowadays around the world, especially in cities with limited development area. In order to pump water up to the higher level of a skyscraper, a cascade water supply system has to be installed. Currently, cascade water supply systems are mainly designed based on practical experiences or requirements of existing standards/guidelines that, in fact, are not specifically for skyscrapers. However, thorough studies on cascade water supply system designs are still limited in the literature. This study proposes mathematical models and uses Monte Carlo simulations to evaluate the design flow rate of a typical cascade water supply system that feeds various appliances in a residential skyscraper in Hong Kong. Graphs that showed the correlations between the inflow rate in the supply pipe and water volume in the tank are obtained. While tank storage volume is confirmed, the design flow rate of the cascade water supply system can be determined from these graphs. The proposed mathematical models can also be applied to evaluate the design flow rate of cascade water supply systems in other types of skyscrapers (e.g., office, commercial building) as well as with the changes in water demand patterns in the models. Full article

(This article belongs to the Section Water, Agriculture and Aquaculture)

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17 pages, 564 KiB

Open AccessEditor’s ChoiceArticle

Industrially Finished Calves: A Water Footprint-Profitability Paradox

by Frikkie Alberts Maré and Henry Jordaan

Water 2019, 11(12), 2565; https://doi.org/10.3390/w11122565 - 5 Dec 2019

Cited by 9 | Viewed by 2791

Abstract

The feed conversion rate is one of the most important determinants of the water footprint (WF) of beef and is known to vary between different cattle breeds. The objective of this study was to estimate the WF of industrially finished calves of seven [...] Read more.

The feed conversion rate is one of the most important determinants of the water footprint (WF) of beef and is known to vary between different cattle breeds. The objective of this study was to estimate the WF of industrially finished calves of seven different cattle breeds on two different feeding regimes: normal pre-determined feeding period (NPFP) and profit-maximising feeding period (PMFP). Data were collected by finishing 35 calves of each of the seven breeds in a feedlot. Green, blue and grey WFs were estimated for the different feeding regimes, and a feedlot simulation provided the effect of the different feeding regimes on the water footprint, financial margin and the water footprint per rand of margin. The results indicated that the water footprint differed notably between breeds on the same feeding regime, as well as between the feeding regimes. While the PMFP had a 1% higher water footprint per year in a typical feedlot than the NPFP, the financial margin was 33% more, resulting in a 24% decrease in the water footprint per South African rand of margin. The contributions of green, blue and grey water to the total WF were 91.5%, 2.5% and 6%, respectively, irrespective of breed or feeding regime. Full article

(This article belongs to the Special Issue Novel Approaches in Water Productivity)

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17 pages, 2794 KiB

Open AccessEditor’s ChoiceArticle

The Endemic Species Flock of Labeobarbus spp. in L. Tana (Ethiopia) Threatened by Extinction: Implications for Conservation Management

by Shewit Gebremedhin, Stijn Bruneel, Abebe Getahun, Wassie Anteneh and Peter Goethals

Water 2019, 11(12), 2560; https://doi.org/10.3390/w11122560 - 4 Dec 2019

Cited by 12 | Viewed by 4279

Abstract

The endemic Labeobarbus species in Lake Tana are severely affected by anthropogenic pressures. The implementation of fisheries management is, therefore, vital for their sustainable exploitation. This study aimed at investigating the catch distribution and size at 50% maturity (FL_50%) of the [...] Read more.

The endemic Labeobarbus species in Lake Tana are severely affected by anthropogenic pressures. The implementation of fisheries management is, therefore, vital for their sustainable exploitation. This study aimed at investigating the catch distribution and size at 50% maturity (FL_50%) of the Labeobarbus species. Samples were collected monthly from May 2016 to April 2017 at four sites. The relative abundance, catch per unit effort (CPUE), and size distribution of these species was computed, and logistic regression was used to calculate FL_50%. Of the 15 species observed, five species constituted 88% of the total catch. The monthly catch of the Labeobarbus spp. declined by more than 85% since 1993 and by 76% since 2001. Moreover, the CPUE of Labeobarbus has markedly decreased from 63 kg/trip in 1991–1993 to 2 kg/trip in 2016–2017. Additionally, large size specimens (≥30 cm fork length) were rarely recorded, and FL_50% of the dominant species decreased. This suggests that the unique species flock may be threatened by extinction. Given the size distribution of the species, the current social context, and the need for a continuous supply of fish for low-income communities, a mesh-size limitation represents a more sustainable and acceptable management measure than a closed season. This paper illustrates the tension between sustainable development goal (SDGs) 1—No Poverty, 2—Zero Hunger, and 8—Decent Work and Economic Growth in Bahir Dar City on the one hand, and SDG’s 11—Sustainable Cities and Communities, 12—Responsible Consumption and Production, and 14—Life Below Water on the other hand. A key for the local, sustainable development of the fisheries is to find a balance between the fishing activities and the carrying capacity of the Lake Tana. Overfishing and illegal fishing are some of the major threats in this respect. Full article

(This article belongs to the Special Issue Sustainable Development of Lakes and Reservoirs)

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20 pages, 2259 KiB

Open AccessEditor’s ChoiceArticle

Quantification of Groundwater Exploitation and Assessment of Water Quality Risk Perception in the Dar Es Salaam Quaternary Aquifer, Tanzania

by Kassim Ramadhani Mussa, Ibrahimu Chikira Mjemah and Kristine Walraevens

Water 2019, 11(12), 2552; https://doi.org/10.3390/w11122552 - 3 Dec 2019

Cited by 11 | Viewed by 6237

Abstract

This study quantified groundwater exploitation and assessed water quality risk perception in the Dar es Salaam quaternary aquifer through a socio-economic survey. Annual total groundwater exploitation was estimated, using the daily per capita consumption of groundwater derived from the household survey. A logistic [...] Read more.

This study quantified groundwater exploitation and assessed water quality risk perception in the Dar es Salaam quaternary aquifer through a socio-economic survey. Annual total groundwater exploitation was estimated, using the daily per capita consumption of groundwater derived from the household survey. A logistic regression analysis was performed to ascertain the influence of sex, marital status, education level, employment, income, and cost of water on groundwater quality risk perception. It was revealed that most residents of Dar es Salaam use groundwater as a main source of water supply. The results of this study further showed that 78% consider groundwater as a reliable source. Averting strategies for insufficient quantity of groundwater consist of minimizing less necessary water uses, while for poor quality, buying bottled water and water treatment by boiling and using chemicals. The chance for water quality risk perception is 0.205 times greater for married than unmarried household heads, and it is 623 times higher for employed versus unemployed household heads. To get an overall view of the importance of groundwater for domestic needs in Dar es Salaam it is imperative to combine a time series data of groundwater and surface water exploitation. Full article

(This article belongs to the Special Issue An Human-Centered Approach to Sustainable Water Management: Applications and Theory in a Data Rich Environment)

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23 pages, 18621 KiB

Open AccessEditor’s ChoiceArticle

Inter-Blade Vortex and Vortex Rope Characteristics of a Pump-Turbine in Turbine Mode under Low Flow Rate Conditions

by Seung-Jun Kim, Jun-Won Suh, Young-Seok Choi, Jungwan Park, No-Hyun Park and Jin-Hyuk Kim

Water 2019, 11(12), 2554; https://doi.org/10.3390/w11122554 - 3 Dec 2019

Cited by 19 | Viewed by 5175

Abstract

Pump-turbines are often used to provide a stable power supply with a constant frequency in response to intermittent renewable energy resources. However, existing pumped-storage power stations often operate under off-design conditions because of the increasing amounts of inconsistent renewable resources that have been [...] Read more.

Pump-turbines are often used to provide a stable power supply with a constant frequency in response to intermittent renewable energy resources. However, existing pumped-storage power stations often operate under off-design conditions because of the increasing amounts of inconsistent renewable resources that have been added to the grid. Under off-design low flow rate conditions, inter-blade vortex and vortex rope phenomena usually develop in the runner and draft tube passages, respectively, in turbine mode. These vortices cause complicated flow patterns and pressure fluctuations that destabilize the operation of the pump-turbine system. Therefore, this study investigates the influence of correlation between the inter-blade vortex and vortex rope phenomena under low flow rate conditions. Three-dimensional steady- and unsteady-state Reynolds-averaged Navier–Stokes equations were calculated with a two-phase flow analysis using a shear stress transport as the turbulence model. The inter-blade vortices in the runner passages were captured well at the low flow rate conditions, and the vortex rope was found to develop within a specific range of low flow rates. These vortex regions showed a blockage effect and complicated flow characteristics with backflow in the passages. Moreover, higher unsteady pressure characteristics occurred at locations where the vortices were especially pronounced. Full article

(This article belongs to the Section Hydraulics and Hydrodynamics)

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14 pages, 4645 KiB

Open AccessEditor’s ChoiceReview

A Comparison of Irrigation-Water Containment Methods and Management Strategies Between Two Ornamental Production Systems to Minimize Water Security Threats

by Andrew G. Ristvey, Bruk E. Belayneh and John D. Lea-Cox

Water 2019, 11(12), 2558; https://doi.org/10.3390/w11122558 - 3 Dec 2019

Cited by 23 | Viewed by 4636

Abstract

Water security in ornamental plant production systems is vital for maintaining profitability. Expensive, complicated, or potentially dangerous treatment systems, together with skilled labor, is often necessary to ensure water quality and plant health. Two contrasting commercial ornamental crop production systems in a mesic [...] Read more.

Water security in ornamental plant production systems is vital for maintaining profitability. Expensive, complicated, or potentially dangerous treatment systems, together with skilled labor, is often necessary to ensure water quality and plant health. Two contrasting commercial ornamental crop production systems in a mesic region are compared, providing insight into the various strategies employed using irrigation-water containment and treatment systems. The first is a greenhouse/outdoor container operation which grows annual ornamental plants throughout the year using irrigation booms, drip emitters, and/or ebb and flow systems depending on the crop, container size, and/or stage of growth. The operation contains and recycles 50–75% of applied water through a system of underground cisterns, using a recycling reservoir and a newly constructed 0.25 ha slow-sand filtration (SSF) unit. Groundwater provides additional water when needed. Water quantity is not a problem in this operation, but disease and water quality issues, including agrochemicals, are of potential concern. The second is a perennial-plant nursery which propagates cuttings and produces field-grown trees and containerized plants. It has a series of containment/recycling reservoirs that capture rainwater and irrigation return water, together with wells of limited output. Water quantity is a more important issue for this nursery, but poor water quality has had some negative economic effects. Irrigation return water is filtered and sanitized with chlorine gas before being applied to plants via overhead and micro-irrigation systems. The agrochemical paclobutrazol was monitored for one year in the first operation and plant pathogens were qualified and quantified over two seasons for both production systems. The two operations employ very different water treatment systems based on their access to water, growing methods, land topography, and capital investment. Each operation has experienced different water quantity and quality vulnerabilities, and has addressed these threats using a variety of technologies and management techniques to reduce their impacts. Full article

(This article belongs to the Special Issue Irrigation and Water Resources Management of Landscape Plants)

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18 pages, 261 KiB

Open AccessEditor’s ChoiceArticle

Rural Piped-Water Enterprises in Cambodia: A Pathway to Women’s Empowerment?

by Melita Grant, Simone Soeters, IV Bunthoeun and Juliet Willetts

Water 2019, 11(12), 2541; https://doi.org/10.3390/w11122541 - 1 Dec 2019

Cited by 16 | Viewed by 6253

Abstract

This research examined the extent to which women’s ownership and management of water supply schemes led to their empowerment, including their economic empowerment, in rural Cambodia. Privately managed water supply schemes in rural Cambodia serve over one million people. This study is the [...] Read more.

This research examined the extent to which women’s ownership and management of water supply schemes led to their empowerment, including their economic empowerment, in rural Cambodia. Privately managed water supply schemes in rural Cambodia serve over one million people. This study is the first of its kind to systematically investigate the experiences and needs of female water supply scheme owners, using well-established theoretical frameworks for women’s empowerment, namely Longwe’s stages of empowerment, and Rowlands, VeneKlasen and Miller’s elaboration on different types of power. Business management frameworks relevant to the water, sanitation and hygiene (WASH) sector were also drawn on to assess operational constraints and enablers. Fifteen structured interviews were conducted with female water entrepreneurs in rural Cambodia. Female entrepreneurs reported encountering four key barriers to establishing and managing water supply schemes. The first were operational, and government and regulatory related issues, followed by financial issues and limited demand for water services. Three important enablers were reported by entrepreneurs: social enablers, economic enablers and program support from government, associations and non-government organisations (NGOs). This study found that, whilst there was evidence of empowerment reported by female water enterprise owners, the complexity of the ongoing empowerment process, challenges and limitations were also observed. Women’s empowerment can be advanced through leadership of, and involvement in water enterprises, as evidenced by this study, however, gender norms constrained women, especially with respect to mobility (leaving the home for extended periods), and household and family duties impacting on income-generating work or vice versa. As such, targeted strategies are needed by a range of actors to address such constraints. The findings of this study can assist NGOs, donors and governments incentivizing entrepreneurship in water services, to ensure that these interventions are not gender blind, and to draw on evidence of the barriers and enablers for female entrepreneurs and how these are influenced by contextualized gender norms. Full article

(This article belongs to the Special Issue Selected Papers from 2019 World Water Week)

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23 pages, 2961 KiB

Open AccessEditor’s ChoiceArticle

Multi-Objective Joint Optimal Operation of Reservoir System and Analysis of Objectives Competition Mechanism: A Case Study in the Upper Reach of the Yangtze River

by Mufeng Chen, Zengchuan Dong, Wenhao Jia, Xiaokuan Ni and Hongyi Yao

Water 2019, 11(12), 2542; https://doi.org/10.3390/w11122542 - 1 Dec 2019

Cited by 23 | Viewed by 4344

Abstract

The multi-objective optimal operation and the joint scheduling of giant-scale reservoir systems are of great significance for water resource management; the interactions and mechanisms between the objectives are the key points. Taking the reservoir system composed of 30 reservoirs in the upper reaches [...] Read more.

The multi-objective optimal operation and the joint scheduling of giant-scale reservoir systems are of great significance for water resource management; the interactions and mechanisms between the objectives are the key points. Taking the reservoir system composed of 30 reservoirs in the upper reaches of the Yangtze River as the research object, this paper constructs a multi-objective optimal operation model integrating four objectives of power generation, ecology, water supply, and shipping under the constraints of flood control to analyze the inside interaction mechanisms among the objectives. The results are as follows. (1) Compared with single power generation optimization, multi-objective optimization improves the benefits of the system. The total power generation is reduced by only 4.09% at most, but the water supply, ecology, and shipping targets are increased by 98.52%, 35.09%, and 100% at most under different inflow conditions, respectively. (2) The competition between power generation and the other targets is the most obvious; the relationship between water supply and ecology depends on the magnitude of flow required by the control section for both targets, and the restriction effect of the shipping target is limited. (3) Joint operation has greatly increased the overall benefits. Compared with the separate operation of each basin, the benefits of power generation, water supply, ecology, and shipping increased by 5.50%, 45.99%, 98.49%, and 100.00% respectively in the equilibrium scheme. This study provides a widely used method to analyze the multi-objective relationship mechanism, and can be used to guide the actual scheduling rules. Full article

(This article belongs to the Section Water Resources Management, Policy and Governance)

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18 pages, 2430 KiB

Open AccessEditor’s ChoiceArticle

Experimental and Numerical Study on Water Filling and Air Expelling Process in a Pipe with Multiple Air Valves under Water Slow Filling Condition

by Jintao Liu, Di Xu, Shaohui Zhang and Meijian Bai

Water 2019, 11(12), 2511; https://doi.org/10.3390/w11122511 - 28 Nov 2019

Cited by 4 | Viewed by 3715

Abstract

This paper investigates the physical processes involved in the water filling and air expelling process of a pipe with multiple air valves under water slow filling condition, and develops a fully coupledwater–air two-phase stratified numerical model for simulating the process. In this model, [...] Read more.

This paper investigates the physical processes involved in the water filling and air expelling process of a pipe with multiple air valves under water slow filling condition, and develops a fully coupledwater–air two-phase stratified numerical model for simulating the process. In this model, the Saint-Venant equations and the Vertical Average Navier–Stokes equations (VANS) are respectively applied to describe the water and air in pipe, and the air valve model is introduced into the VANS equations of air as the source term. The finite-volume method and implicit dual time-stepping method (IDTS) with two-order accuracy are simultaneously used to solve this numerical model to realize the full coupling between water and air movement. Then, the model is validated by using the experimental data of the pressure evolution in pipe and the air velocity evolution of air valves, which respectively characterize the water filling and air expelling process. The results show that the model performs well in capturing the physical processes, and a reasonable agreement is obtained between numerical and experimental results. This agreement demonstrates that the proposed model in this paper offers a practical method for simulating water filling and air expelling process in a pipe with multiple air valves under water slow filling condition. Full article

(This article belongs to the Section Hydraulics and Hydrodynamics)

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20 pages, 2863 KiB

Open AccessEditor’s ChoiceArticle

Building a System Dynamics Model to Support Water Management: A Case Study of the Semiarid Region in the Brazilian Northeast

by Wanderbeg Correia de Araujo, Karla Patricia Oliveira Esquerre and Oz Sahin

Water 2019, 11(12), 2513; https://doi.org/10.3390/w11122513 - 28 Nov 2019

Cited by 34 | Viewed by 6896

Abstract

In recent centuries, water consumption rates have more than doubled and the population growth rate is rising constantly. As a result, water scarcity is now one of the main problems to be faced, mainly in semiarid regions. In light of such a dilemma, [...] Read more.

In recent centuries, water consumption rates have more than doubled and the population growth rate is rising constantly. As a result, water scarcity is now one of the main problems to be faced, mainly in semiarid regions. In light of such a dilemma, this study aims to develop a system dynamics model in order to evaluate the water system in the semiarid region of the state of Paraíba—located in the Brazilian Northeast—and it focus on the following two issues: (1) measures that could have been taken with respect to the recent water crisis (2012–2017); (2) simulating water availability up to 2025. It was observed that, despite the options of in-demand management tools being efficient solutions for water scarcity in the short term (e.g., the influence of scarcity-based tariffs in reducing water use), such tools would not suffice in a context of severe drought within a water-providing system that depends heavily on rainfall. However, certain policies involving water-supply management (e.g., wastewater reuse and inter-basin water transfer) are very effective in maintaining water supply and avoiding a water collapse in the region. Furthermore, employing the Monte Carlo approach in simulating the system dynamic proved that the water supply is sensitive to scarcity-based tariffs, wastewater reuse, and inter-basin water transfer. An important advancement in this study was the simulation of a methodology for pricing that encourages rational use of water-based on its scarcity, which in turn increases revenue and investment in other water-management strategies. Full article

(This article belongs to the Special Issue System Dynamics Modelling for Water–Energy–Climate Nexus)

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18 pages, 3378 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Arsenic Removal from Water by Green Synthesized Magnetic Nanoparticles

by Jasmina Nikić, Aleksandra Tubić, Malcolm Watson, Snežana Maletić, Marko Šolić, Tatjana Majkić and Jasmina Agbaba

Water 2019, 11(12), 2520; https://doi.org/10.3390/w11122520 - 28 Nov 2019

Cited by 43 | Viewed by 6352

Abstract

Magnetite nanoparticles were synthesized by a simple and ecofriendly method using onion peel (MNp-OP) and corn silk extract (MNp-CS), in order to develop new low-cost adsorbents for arsenic removal from groundwater. As a point of comparison, magnetite nanoparticles were also synthesized with a [...] Read more.

Magnetite nanoparticles were synthesized by a simple and ecofriendly method using onion peel (MNp-OP) and corn silk extract (MNp-CS), in order to develop new low-cost adsorbents for arsenic removal from groundwater. As a point of comparison, magnetite nanoparticles were also synthesized with a conventional chemical process (MNp-CO). The antioxidant potential of onion peel and corn silk extracts was determined using ferric reducing antioxidant power (FRAP) and free radical (DPPH) scavenging assays, including the total phenolics, flavonoids and tannins contents. The synthesized magnetite nanoparticles were characterised using different techniques (Scanning electron microscope/Energy dispersive spectroscopy (SEM/EDS), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR) and Brunauer-Emmett-Teller (BET) surface area analyzer). The adsorption capacity of MNp-OP and MNp-CS and the arsenic removal mechanism of these novel adsorbents was investigated through kinetic and equilibrium experiments and their corresponding mathematical models. Characterisation of MNp-OP and MNp-CS shows high BET specific surface areas of 243 m²/g and 261 m²/g, respectively. XRD and FTIR analysis confirmed the formation and presence of magnetite nanoparticles. The arsenic adsorption mechanism on MNp-OP, MNp-CS and MNp-CO involves chemisorption, intraparticle and external diffusion. Maximal adsorption capacities of MNp-OP, MNp-CS and MNp-CO were 1.86, 2.79, and 1.30 mg/g respectively. The green synthesis applied using onion peel and corn silk extracts was cost effective and environmentally friendly, and results in adsorbents with a high capacity for arsenic and magnetic properties, making them a very promising alternative approach in the treatment of arsenic contaminated groundwater. Full article

(This article belongs to the Special Issue Advances in In Situ Biological and Chemical Groundwater Treatment)

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19 pages, 3626 KiB

Open AccessEditor’s ChoiceArticle

Gendered Water Insecurity: A Structural Equation Approach for Female Headed Households in South Africa

by Saul Ngarava, Leocadia Zhou and Nomakhaya Monde

Water 2019, 11(12), 2491; https://doi.org/10.3390/w11122491 - 26 Nov 2019

Cited by 14 | Viewed by 6100

Abstract

Intricacies between women and water are central to achieving the 2030 Sustainable Development Goals (SDGs). Gender equality and women empowerment is a key driver in ending hunger and poverty as well as improve water security the study sought to identify and provide pathways [...] Read more.

Intricacies between women and water are central to achieving the 2030 Sustainable Development Goals (SDGs). Gender equality and women empowerment is a key driver in ending hunger and poverty as well as improve water security the study sought to identify and provide pathways through which female-headed households were water insecure in South Africa. Secondary data collected during the 2016 General Household Survey (GHS) was utilised, with a sample of 5928 female-headed households. Principal Component Analysis and Structural Equation Modelling were used to analyse the data. The results show dynamic relationships between water characteristics and water treatment. There were also associations between water access and wealth status of the female-headed households. Association was also found between water access and water treatment as well as between wealth status and water treatment. The study concludes that there are dynamic relationships in water insecurity (exposure, sensitivity and adaptive capacity) for female-headed households in South Africa. The study recommends that a multi-prong approach is required in tackling exposures, sensitivities and adaptive capacities to water insecurity. This should include capacity–building and empowering women for wealth generation, improve access to water treatment equipment as well as prioritising improvement of infrastructure that brings piped and safe water to female-headed households. Full article

(This article belongs to the Special Issue Water Security)

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19 pages, 1666 KiB

Open AccessEditor’s ChoiceCommunication

Planning in Democratizing River Basins: The Case for a Co-Productive Model of Decision Making

by Tira Foran, David J. Penton, Tarek Ketelsen, Emily J. Barbour, Nicola Grigg, Maheswor Shrestha, Louis Lebel, Hemant Ojha, Auro Almeida and Neil Lazarow

Water 2019, 11(12), 2480; https://doi.org/10.3390/w11122480 - 25 Nov 2019

Cited by 5 | Viewed by 4567

Abstract

We reflect on methodologies to support integrated river basin planning for the Ayeyarwady Basin in Myanmar, and the Kamala Basin in Nepal, to which we contributed from 2017 to 2019. The principles of Integrated Water Resources Management have been promoted across states and [...] Read more.

We reflect on methodologies to support integrated river basin planning for the Ayeyarwady Basin in Myanmar, and the Kamala Basin in Nepal, to which we contributed from 2017 to 2019. The principles of Integrated Water Resources Management have been promoted across states and regions with markedly different biophysical and political economic conditions. IWRM-based river basin planning is complex, resource intensive, and aspirational. It deserves scrutiny to improve process and outcome legitimacy. We focus on the value of co-production and deliberation in IWRM. Among our findings: (i) multi-stakeholder participation can be complicated by competition between actors for resources and legitimacy; (ii) despite such challenges, multi-stakeholder deliberative approaches can empower actors and can be an effective means for co-producing knowledge; (iii) tensions between (rational choice and co-productive) models of decision complicate participatory deliberative planning. Our experience suggests that a commitment to co-productive decision-making fosters socially legitimate IWRM outcomes. Full article

(This article belongs to the Special Issue Managing Water Resources in Large River Basins)

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10 pages, 1228 KiB

Open AccessEditor’s ChoiceCommunication

EU Horizon 2020 Research for A Sustainable Future: INNOQUA—A Nature-Based Sanitation Solution

by David Tompkins, Costel Bumbac, Eoghan Clifford, Jean-Baptiste Dussaussois, Louise Hannon, Victòria Salvadó and Tatjana Schellenberg

Water 2019, 11(12), 2461; https://doi.org/10.3390/w11122461 - 23 Nov 2019

Cited by 10 | Viewed by 5906

Abstract

This paper explores the experiences of partners in the multi-national, EU-funded INNOQUA project, who have developed and are currently demonstrating the potential for novel nature-based, decentralised wastewater treatment solutions in ten different countries. Four solutions are under investigation, each at different Technology Readiness [...] Read more.

This paper explores the experiences of partners in the multi-national, EU-funded INNOQUA project, who have developed and are currently demonstrating the potential for novel nature-based, decentralised wastewater treatment solutions in ten different countries. Four solutions are under investigation, each at different Technology Readiness Levels (TRLs): Lumbrifilter; Daphniafilter; Bio-Solar Purification unit; UV disinfection unit. An overview of the solutions is provided, along within data from pilot sites. The project is currently entering an intensive demonstration phase, during which sites will be open for visits and act as the focus for training and dissemination activities on sustainable wastewater treatment. Barriers to market for nature-based solutions are also explored. Full article

(This article belongs to the Special Issue Selected Papers from 2019 World Water Week)

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12 pages, 748 KiB

Open AccessEditor’s ChoiceArticle

Testing An Adoption Decision-Making Model of Nursery and Greenhouse Growers’ Water Reuse in the United States

by Alexa J. Lamm, Laura A. Warner, Abraham Tidwell, Kevan W. Lamm, Paul R. Fisher and Sarah White

Water 2019, 11(12), 2470; https://doi.org/10.3390/w11122470 - 23 Nov 2019

Cited by 3 | Viewed by 3389

Abstract

There is an increasing necessity to implement water treatment technologies in order to optimize the use of freshwater resources as the global nursery and greenhouse industry grows. Unfortunately, their adoption has been limited. This study tested a conceptual model for technology adoption based [...] Read more.

There is an increasing necessity to implement water treatment technologies in order to optimize the use of freshwater resources as the global nursery and greenhouse industry grows. Unfortunately, their adoption has been limited. This study tested a conceptual model for technology adoption based on the Theory of Diffusion of Innovations in tandem with Adaption-Innovation Theory and Critical Thinking Style literature. Using a series of linear and logistic regressions, three characteristics of an innovation—relative advantage, complexity, and trialability—were identified as significant drivers of growers’ decisions to implement water treatment technologies. Growers who seek information when thinking critically and are more innovative when solving problems did not perceive new technologies to be compatible or to possess a relative advantage over their current systems. The results suggested most growers are unsure of how new technologies fit into their existing operations. Creating opportunities for growers to get hands on experience with new technologies, such as a field day, could assist in increasing growers’ implementation. In addition, developing a series of online videos highlighting how to use, adapt and troubleshoot the equipment would greatly enhance chances of long-term adoption. Full article

(This article belongs to the Special Issue Irrigation and Water Resources Management of Landscape Plants)

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22 pages, 5308 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Participatory Modelling of Surface and Groundwater to Support Strategic Planning in the Ganga Basin in India

by Marnix van der Vat, Pascal Boderie, Kees (C.) A. Bons, Mark Hegnauer, Gerrit Hendriksen, Mijke van Oorschot, Bouke Ottow, Frans Roelofsen, R.N. Sankhua, S.K. Sinha, Andrew Warren and William Young

Water 2019, 11(12), 2443; https://doi.org/10.3390/w11122443 - 21 Nov 2019

Cited by 10 | Viewed by 13139

Abstract

The Ganga Basin in India experiences problems related to water availability, water quality and ecological degradation because of over-abstraction of surface and groundwater, the presence of various hydraulic infrastructure, discharge of untreated sewage water, and other point and non-point source pollution. The basin [...] Read more.

The Ganga Basin in India experiences problems related to water availability, water quality and ecological degradation because of over-abstraction of surface and groundwater, the presence of various hydraulic infrastructure, discharge of untreated sewage water, and other point and non-point source pollution. The basin is experiencing rapid socio-economic development that will increase both the demand for water and pollution load. Climate change adds to the uncertainty and future variability of water availability. To support strategic planning for the Ganga Basin by the Indian Ministry of Water Resources, River Development and Ganga Rejuvenation and the governments of the concerned Indian states, a river basin model was developed that integrates hydrology, geohydrology, water resources management, water quality and ecology. The model was developed with the involvement of key basin stakeholders across central and state governments. No previous models of the Ganga Basin integrate all these aspects, and this is the first time that a participatory approach was applied for the development of a Ganga Basin model. The model was applied to assess the impact of future socio-economic and climate change scenarios and management strategies. The results suggest that the impact of socio-economic development will far exceed the impacts of climate change. To balance the use of surface and groundwater to support sustained economic growth and an ecologically healthy river, it is necessary to combine investments in wastewater treatment and reservoir capacity with interventions that reduce water demand, especially for irrigation, and that increase dry season river flow. An important option for further investigation is the greater use of alluvial aquifers for temporary water storage. Full article

(This article belongs to the Special Issue Managing Water Resources in Large River Basins)

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23 pages, 7239 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Real-Time, Smart Rainwater Storage Systems: Potential Solution to Mitigate Urban Flooding

by Ruijie Liang, Michael Di Matteo, Holger R. Maier and Mark A. Thyer

Water 2019, 11(12), 2428; https://doi.org/10.3390/w11122428 - 20 Nov 2019

Cited by 29 | Viewed by 7615

Abstract

Urban water systems are being stressed due to the effects of urbanization and climate change. Although household rainwater tanks are primarily used for water supply purposes, they also have the potential to provide flood benefits. However, this potential is limited for critical storms, [...] Read more.

Urban water systems are being stressed due to the effects of urbanization and climate change. Although household rainwater tanks are primarily used for water supply purposes, they also have the potential to provide flood benefits. However, this potential is limited for critical storms, as they become ineffective once their capacity is exceeded. This limitation can be overcome by controlling tanks as systems during rainfall events, as this can offset the timing of outflow peaks from different tanks. In this paper, the effectiveness of such systems is tested for two tank sizes under a wide range of design rainfall conditions for three Australian cities with different climates. Results show that a generic relationship exists between the ratio of tank:runoff volume and percentage peak flow reduction, irrespective of location and storm characteristics. Smart tank systems are able to reduce peak system outflows by between 35% and 85% for corresponding ranges in tank:runoff volumes of 0.15–0.8. This corresponds to a relative performance improvement on the order of 35% to 50% compared with smart tanks that are not operated in real-time. These results highlight the potential for using household rainwater tanks for mitigating urban flooding, even for extreme events. Full article

(This article belongs to the Special Issue Smart Technologies and Water Supply Planning)

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22 pages, 1375 KiB

Open AccessEditor’s ChoiceArticle

Mobilising Finance for WASH: Getting the Foundations Right

by Lesley Pories, Catarina Fonseca and Victoria Delmon

Water 2019, 11(11), 2425; https://doi.org/10.3390/w11112425 - 19 Nov 2019

Cited by 18 | Viewed by 9321

Abstract

Responding to the substantial finance gap for achieving Sustainable Development Goals 6.1 and 6.2, the water and sanitation sector has mobilized to launch new blended finance vehicles with increasing frequency. The sustainability and scale-up of financial solutions is intended to support increased access [...] Read more.

Responding to the substantial finance gap for achieving Sustainable Development Goals 6.1 and 6.2, the water and sanitation sector has mobilized to launch new blended finance vehicles with increasing frequency. The sustainability and scale-up of financial solutions is intended to support increased access to unserved, marginalized populations. However, without addressing foundational issues in the sector, any finance mechanism, whether public, private or blended, will be a short-term, band-aid solution and the sector will continue the cycle of dependency on external assistance. This paper presents the results of a collaborative effort of Water.org; the IRC water, sanitation and hygiene sector (WASH); and the World Bank Water Global Practice. Drawing from the latest research on effective public financial management and based on evidence from the countries where these organizations work, the paper demonstrates that sustainable success in mobilising finance on a large scale is dependent on a reasonable level of performance across 10 foundational areas. The paper presents evidence on the 10 foundational areas and discusses why other aspects of finance and governance, while necessary, are not sufficient. Better coordination amongst all development partners and governments, including a collective commitment to and prioritization of working on these foundational issues, is a necessary first step. Full article

(This article belongs to the Special Issue Selected Papers from 2019 World Water Week)

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22 pages, 3176 KiB

Open AccessEditor’s ChoiceArticle

Mainstreaming Gender into Irrigation: Experiences from Pakistan

by Junaid Alam Memon, Bethany Cooper and Sarah Wheeler

Water 2019, 11(11), 2408; https://doi.org/10.3390/w11112408 - 16 Nov 2019

Cited by 10 | Viewed by 9394

Abstract

The influence of gender in participatory irrigation management reforms has been the subject of significant research in the past. Whilst there is some understanding of what hinders women and marginalized groups from participating in irrigation management, there is limited understanding of how male [...] Read more.

The influence of gender in participatory irrigation management reforms has been the subject of significant research in the past. Whilst there is some understanding of what hinders women and marginalized groups from participating in irrigation management, there is limited understanding of how male and female farmers vary in their perceptions on the effectiveness of participation in irrigation affairs. There is also limited understanding around the interaction on gender and the overall success of participatory irrigation management programs. Based on the information obtained from 128 households surveyed through separate male and female questionnaires in Pakistan in 2018 (Sindh and Punjab provinces), we studied the country’s experience in engaging gender into its participatory irrigation management program. We found there was a significant difference in participatory irrigation management perceptions across both gender and locational jurisdiction. Overall, women generally perceive the performance and impact of farmer organizations to be significantly less effective than men. Our study emphasizes the importance of putting findings in a historical context to inform the theory, policy, and practice of mainstreaming gender into irrigation management. Full article

(This article belongs to the Special Issue Using Applied Economics to Study Participatory Irrigation Institutions and their Impact in South Asia)

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16 pages, 2058 KiB

Open AccessEditor’s ChoiceArticle

Cool Steam Method for Desalinating Seawater

by Pedro Antonio Arnau, Naeria Navarro, Javier Soraluce, Jose María Martínez-Iglesias, Jorge Illas and Eugenio Oñate

Water 2019, 11(11), 2385; https://doi.org/10.3390/w11112385 - 14 Nov 2019

Cited by 3 | Viewed by 5017

Abstract

Cool steam is an innovative distillation technology based on low-temperature thermal distillation (LTTD), which allows obtaining fresh water from non-safe water sources with substantially low energy consumption. LTTD consists of distilling at low temperatures by lowering the working pressure and making the most [...] Read more.

Cool steam is an innovative distillation technology based on low-temperature thermal distillation (LTTD), which allows obtaining fresh water from non-safe water sources with substantially low energy consumption. LTTD consists of distilling at low temperatures by lowering the working pressure and making the most of low-grade heat sources (either natural or artificial) to evaporate water and then condensate it at a cooler heat sink. To perform the process, an external heat source is needed that provides the latent heat of evaporation and a temperature gradient to maintain the distillation cycle. Depending on the available temperature gradient, several stages can be implemented, leading to a multi-stage device. The cool steam device can thus be single or multi-stage, being raw water fed to every stage from the top and evaporated in contact with the warmer surface within the said stage. Acting as a heat carrier, the water vapor travels to the cooler surface and condensates in contact with it. The latent heat of condensation is then conducted through the conductive wall to the next stage. Net heat flux is then established from the heat source until the heat sink, allowing distilling water inside every parallel stage. Full article

(This article belongs to the Special Issue Sustainable Design for Seawater Desalination)

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17 pages, 3166 KiB

Open AccessEditor’s ChoiceArticle

Long-Term Deceleration of Glaciers in the Eastern Nyainqentanglha Mountains, Southeastern Tibetan Plateau, Revealed from Landsat Images

by Xiyou Fu and Jianmin Zhou

Water 2019, 11(11), 2387; https://doi.org/10.3390/w11112387 - 14 Nov 2019

Cited by 5 | Viewed by 2823

Abstract

Temperate glaciers are very sensitive to variations in temperature and precipitation, and thus represent a good indicator of climate change. By exploiting complete Landsat archives during periods of 1988–1990, 2000–2002 and 2014–2016, we derived three velocity maps of the temperate glaciers on the [...] Read more.

Temperate glaciers are very sensitive to variations in temperature and precipitation, and thus represent a good indicator of climate change. By exploiting complete Landsat archives during periods of 1988–1990, 2000–2002 and 2014–2016, we derived three velocity maps of the temperate glaciers on the eastern Nyainqêntanglha Mountains in southeastern Tibetan to reveal the long-term changes of glacier surface velocity. Our results show that all the investigated glaciers experienced deceleration, with rates of deceleration varying from 4.15% to 29.8% per decade during the period from 1988–1990 to 2014–2016, showing heterogeneous deceleration patterns. A significant rise in temperature and an insignificant decrease in precipitation was found from the meteorological data of the nearby meteorological station. The region-wide deceleration of glaciers was, thus, attributed to the negative mass balance induced mainly by the rise in temperature. The averaged rates of deceleration for periods from 1988–1990 to 2000–2002 and from 2000–2002 to 2014–2016 are 20.97% and 22.02% per decade, respectively, indicating a nearly even speed of deceleration in velocities during study periods. The nearly even speed of deceleration in velocities and the accelerating mass loss trend from periods before the 2000s to after the 2000s highlighted the complexity of the relationship between mass balance and glacier velocity. Full article

(This article belongs to the Section Water Resources Management, Policy and Governance)

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20 pages, 4620 KiB

Open AccessEditor’s ChoiceArticle

Flood Risk Mapping Worldwide: A Flexible Methodology and Toolbox

by Hanne Glas, Ivan Rocabado, Steven Huysentruyt, Edith Maroy, Danitza Salazar Cortez, Kobe Coorevits, Philippe De Maeyer and Greet Deruyter

Water 2019, 11(11), 2371; https://doi.org/10.3390/w11112371 - 13 Nov 2019

Cited by 10 | Viewed by 7881

Abstract

Flood risk assessments predict the potential consequences of flooding, leading to more effective risk management and strengthening resilience. However, adequate assessments rely on large quantities of high-quality input data. Developing regions lack reliable data or funds to acquire them. Therefore, this research has [...] Read more.

Flood risk assessments predict the potential consequences of flooding, leading to more effective risk management and strengthening resilience. However, adequate assessments rely on large quantities of high-quality input data. Developing regions lack reliable data or funds to acquire them. Therefore, this research has developed a flexible, low-cost methodology for mapping flood hazard, vulnerability and risk. A generic methodology was developed and customized for freely available data with global coverage, enabling risk assessment worldwide. The default workflow can be enriched with region-specific information when available. The practical application is assured by a modular toolbox developed on GDAL and PCRASTER. This toolbox was tested for the catchment of the river Moustiques, Haiti, for which several flood hazard maps were developed. Then, the toolbox was used to create social, economic and physical vulnerability maps. These were combined with the hazard maps to create the three corresponding flood risk maps. After creating these with the default data, more detailed information, gathered during field work, was added to verify the results of the basic workflow. These first tests of the developed toolbox show promising results. The toolbox allows policy makers in developing countries to perform reliable flood risk assessments and generate the necessary maps. Full article

(This article belongs to the Special Issue Selected Papers from 2019 World Water Week)

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16 pages, 6989 KiB

Open AccessEditor’s ChoiceArticle

Long-Term Hydropower Generation Scheduling of Large-Scale Cascade Reservoirs Using Chaotic Adaptive Multi-Objective Bat Algorithm

by Lyuwen Su, Kan Yang, Hu Hu and Zhe Yang

Water 2019, 11(11), 2373; https://doi.org/10.3390/w11112373 - 13 Nov 2019

Cited by 13 | Viewed by 2730

Abstract

With growing concerns over renewable energy, the cascade hydropower reservoirs operation (CHRO), which balances the development of economic benefits and power supply security, plays an increasingly important role in hydropower systems. Due to conflicting objectives and complicated operation constraints, the CHRO problem considering [...] Read more.

With growing concerns over renewable energy, the cascade hydropower reservoirs operation (CHRO), which balances the development of economic benefits and power supply security, plays an increasingly important role in hydropower systems. Due to conflicting objectives and complicated operation constraints, the CHRO problem considering the requirements of maximizing power generation benefit and firm power output is determined as a multi-objective optimization problem (MOP). In this paper, a chaotic adaptive multi-objective bat algorithm (CAMOBA) is proposed to solve the CHRO problem, and the external archive set is added to preserve non-dominant solutions. Meanwhile, population initialization based on the improved logical mapping function is adopted to improve population diversity. Furthermore, the self-adaptive local search strategy and mutation operation are designed to escape local minima. The CAMOBA is applied to the CHRO problem of the Qingjiang cascade hydropower stations in southern China. The results show that CAMOBA outperforms the multi-objective bat algorithm (MOBA) and non-dominated sorting genetic algorithms-II (NSGA-II) in different hydrological years. The spacing (SP) and hypervolume (HV) metrics verify the excellent performance of CAMOBA in diversity and convergence. In summary, the CAMOBA is demonstrated to get better scheduling solutions, providing an effective approach for solving the cascade hydropower reservoirs operation (CHRO). Full article

(This article belongs to the Section Water Resources Management, Policy and Governance)

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19 pages, 3771 KiB

Open AccessEditor’s ChoiceArticle

Synergies within the Water-Energy-Food Nexus to Support the Integrated Urban Resources Governance

by Guijun Li, Yongsheng Wang and Yulong Li

Water 2019, 11(11), 2365; https://doi.org/10.3390/w11112365 - 12 Nov 2019

Cited by 24 | Viewed by 5564

Abstract

Rapid urbanization poses great challenges to water-energy-food nexus (WEF-Nexus) system, calling for integrative resources governance to improve the synergies between subsystems that constitute the Nexus. This paper explores the synergies within the WEF-Nexus in Shenzhen city while using the synergetic model. We first [...] Read more.

Rapid urbanization poses great challenges to water-energy-food nexus (WEF-Nexus) system, calling for integrative resources governance to improve the synergies between subsystems that constitute the Nexus. This paper explores the synergies within the WEF-Nexus in Shenzhen city while using the synergetic model. We first identify the order parameters and their causal paths in three subsystems and set several eigenvectors under each parameter. Secondly, a synergetic model is developed to calculate the synergy degree among parameters, and the synergetic networks are then further constructed. Centrality analysis on the synergetic networks reveals that the centralities of food subsystem perform the highest level while the water subsystem at the lowest level. Finally, we put forward some policy implications for cross-sectoral resources governance by embedding the synergy degree into causal paths. The results show that the synergies of the Nexus system in Shenzhen can be maximized by stabilizing water supply, coordinating the energy imports and exports, and reducing the crops sown areas. Full article

(This article belongs to the Special Issue Insights on the Water–Energy–Food Nexus)

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19 pages, 3947 KiB

Open AccessEditor’s ChoiceArticle

Estimating River Discharges in Ungauged Catchments Using the Slope–Area Method and Unmanned Aerial Vehicle

by Shengtian Yang, Pengfei Wang, Hezhen Lou, Juan Wang, Changsen Zhao and Tongliang Gong

Water 2019, 11(11), 2361; https://doi.org/10.3390/w11112361 - 11 Nov 2019

Cited by 35 | Viewed by 5385

Abstract

River discharge is of great significance in the development of water resources and ecological protection. There are several large ungauged catchments around the word still lacking sufficient hydrological data. Obtaining accurate hydrological information from these areas is an important scientific issue. New data [...] Read more.

River discharge is of great significance in the development of water resources and ecological protection. There are several large ungauged catchments around the word still lacking sufficient hydrological data. Obtaining accurate hydrological information from these areas is an important scientific issue. New data and methods must be used to address this issue. In this study, a new method that couples unmanned aerial vehicle (UAV) data with the classical slope–area method is developed to calculate river discharges in typical ungauged catchments. UAV data is used to obtain topographic information of the river channels. In situ experiments are carried out to validate the river data. Based on slope–area method, namely the Manning–Strickler formula (M–S), Saint-Venant system of equivalence (which has two definitions, S-V-1 and S-V-2), and the Darcy–Weisbach equivalence (D–W) are used to estimate river discharge in ten sections of the Tibet Plateau and Dzungaria Basin. Results show that the overall qualification rate of the calculated discharge is 70% and the average Nash–Sutcliffe efficiency coefficient is 0.97, indicating strong practical application in the study area. When the discharge is less than 10 m³⁄s, D–W is the most appropriate method; M–S and S-V-1 are better than other methods when the discharge is between 10 m³⁄s and 50 m³⁄s. However, if the discharge is greater than 50 m³⁄s, S-V-2 provides the most accurate results. Furthermore, we found that hydraulic radius is an important parameter in the slope–area method. This study offers a quick and convenient solution to extract hydrological information in ungauged catchments. Full article

(This article belongs to the Section Water Resources Management, Policy and Governance)

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22 pages, 1010 KiB

Open AccessEditor’s ChoiceReview

Role of Design and Operational Factors in the Removal of Pharmaceuticals by Constructed Wetlands

by Huma Ilyas and Eric D. van Hullebusch

Water 2019, 11(11), 2356; https://doi.org/10.3390/w11112356 - 10 Nov 2019

Cited by 59 | Viewed by 5724

Abstract

This study evaluates the role of design, operational, and physicochemical parameters of constructed wetlands (CWs) in the removal of pharmaceuticals (PhCs). The correlation analysis demonstrates that the performance of CWs is governed by several design and operational factors (area, depth, hydraulic loading rate, [...] Read more.

This study evaluates the role of design, operational, and physicochemical parameters of constructed wetlands (CWs) in the removal of pharmaceuticals (PhCs). The correlation analysis demonstrates that the performance of CWs is governed by several design and operational factors (area, depth, hydraulic loading rate, organic loading rate, and hydraulic retention time), and physicochemical parameters (dissolved oxygen, temperature, and pH); the removal efficiency of about 50% of the examined PhCs showed a significant correlation with two or more factors. Plants contributed significantly in the removal of some of the PhCs by direct uptake and by enhancing the process of aerobic biodegradation. The use of substrate material of high adsorption capacity, rich in organic matter, and with high surface area enhanced the removal of PhCs by adsorption/sorption processes, which are the major removal mechanisms of some PhCs (codeine, clarithromycin, erythromycin, ofloxacin, oxytetracycline, carbamazepine, and atenolol) in CWs. Although the removal of almost all of the studied PhCs showed seasonal differences, statistical significance was established in the removal of naproxen, salicylic acid, caffeine, and sulfadiazine. The effective PhCs removal requires the integrated design of CWs ensuring the occurrence of biodegradation along with other processes, as well as enabling optimal values of design and operational factors, and physicochemical parameters. Full article

(This article belongs to the Section Wastewater Treatment and Reuse)

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12 pages, 1042 KiB

Open AccessEditor’s ChoiceArticle

Significance of Chlorinated Phenols Adsorption on Plastics and Bioplastics during Water Treatment

by Aleksandra Tubić, Maja Lončarski, Snežana Maletić, Jelena Molnar Jazić, Malcolm Watson, Jelena Tričković and Jasmina Agbaba

Water 2019, 11(11), 2358; https://doi.org/10.3390/w11112358 - 10 Nov 2019

Cited by 43 | Viewed by 4948

Abstract

Microplastics and chlorinated phenols (CPs) are pollutants found ubiquitously in freshwater systems. Meanwhile, bioplastics are attracting much attention as alternatives to conventional plastics, but there is little data about their effect on the behaviour of pollutants. This work therefore investigates the sorption of [...] Read more.

Microplastics and chlorinated phenols (CPs) are pollutants found ubiquitously in freshwater systems. Meanwhile, bioplastics are attracting much attention as alternatives to conventional plastics, but there is little data about their effect on the behaviour of pollutants. This work therefore investigates the sorption of four CPs (4-chlorophenol—4-CP, 2,4-dichlorophenol—2,4-DCP, 2,4,6-trichlorophenol—2,4,6-TCP and pentachlorophenol—PCP) on three different plastics (polyethylene (PЕg), polypropylene (PP) and polylactic acid (PLA)) using kinetics and isotherm studies. All experiments were carried out in a synthetic water matrix and in spiked Danube river water. In all cases, adsorption kinetics fitted well with the pseudo-second order rate model. Adsorption proceeded through two linear phases, corresponding to transport from the bulk solution to the external surfaces and then into the interior pores of the sorbents. Maximum adsorption capacities calculated with the Langmuir isotherm indicated that whereas adsorption of 4-CP was not significantly affected by the type of plastic present, the adsorption of 2,4-DCP, 2,4,6-TCP and PCP varied greatly, with polypropylene showing the greatest affinity for CPs adsorption. The differences observed between the adsorption behaviour of CPs in the synthetic and natural water matrices suggest further investigation is required into how the different fractions of natural organic matter impact interactions between CPs and plastics. Full article

(This article belongs to the Special Issue Advances in In Situ Biological and Chemical Groundwater Treatment)

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18 pages, 1436 KiB

Open AccessEditor’s ChoiceArticle

Irrigation-Advisor—A Decision Support System for Irrigation of Vegetable Crops

by José M. Mirás-Avalos, José S. Rubio-Asensio, Juan M. Ramírez-Cuesta, José F. Maestre-Valero and Diego S. Intrigliolo

Water 2019, 11(11), 2245; https://doi.org/10.3390/w11112245 - 26 Oct 2019

Cited by 24 | Viewed by 5368

Abstract

Climate change will intensify water scarcity, and therefore irrigation must be adapted to save water. Operational tools that provide watering recommendations to end-users are needed. This work presents a new tool, Irrigation-Advisor (IA), which is based on weather forecasts and is able to [...] Read more.

Climate change will intensify water scarcity, and therefore irrigation must be adapted to save water. Operational tools that provide watering recommendations to end-users are needed. This work presents a new tool, Irrigation-Advisor (IA), which is based on weather forecasts and is able to separately determine soil evaporation and crop transpiration, and thus is adaptable to a broad range of agricultural situations. By calculating several statistical indicators, IA was tested against the FAO-56 crop evapotranspiration (ET_cFAO) methodology using local crop coefficients. Additionally, IA recommendations were compared with current standard practices by experienced farmers (F). Six field experiments with four widely cultivated species (endive, lettuce, muskmelon and potato) were performed in Southeast Spain. Irrigation water applied, crop yield, aboveground biomass and water productivity were determined. Crop water needs underestimations (5%–20%) were detected when comparing IA against ET_cFAO, although the index of agreement proved reasonable adjustments. The IA recommendations led to water savings up to 13% when compared to F, except for lettuce, with a 31% surplus in irrigation when using IA. Crop yield was not compromised and water productivity was increased by IA. Therefore, IA mimicked the farmers′ irrigation strategies fairly well without deploying sensors on-site. Nevertheless, improvements are needed for increasing the accuracy of IA estimations. Full article

(This article belongs to the Special Issue Agriculture Water Management and Water Saving Strategies)

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32 pages, 621 KiB

Open AccessEditor’s ChoiceReview

Integrated Solutions for the Water-Energy-Land Nexus: Are Global Models Rising to the Challenge?

by Nils Johnson, Peter Burek, Edward Byers, Giacomo Falchetta, Martina Flörke, Shinichiro Fujimori, Petr Havlik, Mohamad Hejazi, Julian Hunt, Volker Krey, Simon Langan, Nebojsa Nakicenovic, Amanda Palazzo, Alexander Popp, Keywan Riahi, Michiel van Dijk, Michelle T.H. van Vliet, Detlef P. van Vuuren, Yoshihide Wada, David Wiberg, Barbara Willaarts, Caroline Zimm and Simon Parkinson Show full author list Hide full author list

Water 2019, 11(11), 2223; https://doi.org/10.3390/w11112223 - 25 Oct 2019

Cited by 28 | Viewed by 8316

Abstract

Increasing human demands for water, energy, food and materials, are expected to accentuate resource supply challenges over the coming decades. Experience suggests that long-term strategies for a single sector could yield both trade-offs and synergies for other sectors. Thus, long-term transition pathways for [...] Read more.

Increasing human demands for water, energy, food and materials, are expected to accentuate resource supply challenges over the coming decades. Experience suggests that long-term strategies for a single sector could yield both trade-offs and synergies for other sectors. Thus, long-term transition pathways for linked resource systems should be informed using nexus approaches. Global integrated assessment models can represent the synergies and trade-offs inherent in the exploitation of water, energy and land (WEL) resources, including the impacts of international trade and climate policies. In this study, we review the current state-of-the-science in global integrated assessment modeling with an emphasis on how models have incorporated integrated WEL solutions. A large-scale assessment of the relevant literature was performed using online databases and structured keyword search queries. The results point to the following main opportunities for future research and model development: (1) improving the temporal and spatial resolution of economic models for the energy and water sectors; (2) balancing energy and land requirements across sectors; (3) integrated representation of the role of distribution infrastructure in alleviating resource challenges; (4) modeling of solution impacts on downstream environmental quality; (5) improved representation of the implementation challenges stemming from regional financial and institutional capacity; (6) enabling dynamic multi-sectoral vulnerability and adaptation needs assessment; and (7) the development of fully-coupled assessment frameworks based on consistent, scalable, and regionally-transferable platforms. Improved database management and computational power are needed to address many of these modeling challenges at a global-scale. Full article

(This article belongs to the Special Issue Integrated Assessment of the Water–Energy–Land Nexus)

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9 pages, 789 KiB

Open AccessEditor’s ChoiceArticle

Sustainable Irrigation Using Non-Conventional Resources: What has Happened after 30 Years Regarding Boron Phytotoxicity?

by Vanessa Mendoza-Grimón, Juan Ramón Fernández-Vera, Jose Manuel Hernández-Moreno and María del Pino Palacios-Díaz

Water 2019, 11(9), 1952; https://doi.org/10.3390/w11091952 - 19 Sep 2019

Cited by 20 | Viewed by 4310

Abstract

In the Canary Islands, there is a hydrological imbalance between water consumption and renewable water availability. To provide more water resources, reverse osmosis (RO) from seawater is used. As boron (B) contents in irrigation water higher than 0.7 mg/L may be dangerous for [...] Read more.

In the Canary Islands, there is a hydrological imbalance between water consumption and renewable water availability. To provide more water resources, reverse osmosis (RO) from seawater is used. As boron (B) contents in irrigation water higher than 0.7 mg/L may be dangerous for sensible plants, B concentration in RO water (ROW) may be one of the key factors of irrigation sustainability. Some orchards have been studied after they have used drip irrigation using different water qualities for 30 years. B in water, soils, and banana leaves was determined to check the sustainability of ROW irrigation. When irrigating with ROW, in which B concentration varies between 1.0 and 1.4 mgB/L, B content in banana soils seems to be stabilized at 5–7 mg/kg, and no toxicity has been observed in banana leaves. The proper water and soil management used by the local farmers probably prevent the accumulation of higher B levels in soils. Considering water consumption of 9000 m³∙ha⁻¹∙year⁻¹, 8−11 kgB∙ha⁻¹∙year⁻¹ is applied to the soil. The banana plant removes approximately 1 kgB∙ha⁻¹∙year⁻¹; therefore, only 10% of the total B added gets exported. This raises the following question: is it better to use membranes that are able to reduce B in ROW, increase the leaching fraction, or blend water? Full article

(This article belongs to the Special Issue Desalination of Seawater for Agricultural Irrigation)

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27 pages, 4668 KiB

Open AccessEditor’s ChoiceArticle

A Comprehensive Modelling Approach to Assess Water Use Efficiencies of Different Irrigation Management Options in Rice Irrigation Districts of Northern Italy

by Alice Mayer, Michele Rienzner, Sandra Cesari de Maria, Marco Romani, Alberto Lasagna and Arianna Facchi

Water 2019, 11(9), 1833; https://doi.org/10.3390/w11091833 - 4 Sep 2019

Cited by 16 | Viewed by 4272

Abstract

European rice production is concentrated in limited areas of a small number of countries. Italy is the largest European producer with over half of the total production grown on an area of 220,000 hectares, predominantly located in northern Italy. The traditional irrigation management [...] Read more.

European rice production is concentrated in limited areas of a small number of countries. Italy is the largest European producer with over half of the total production grown on an area of 220,000 hectares, predominantly located in northern Italy. The traditional irrigation management (wet seeding and continuous flooding until few weeks before harvest—WFL) requires copious volumes of water. In order to propose effective ‘water-saving’ irrigation alternatives, there is the need to collect site-specific observational data and, at the same time, to develop agro-hydrological models to upscale field/farm experimental data to a spatial scale of interest to support water management decisions and policies. The semi-distributed modelling system developed in this work, composed of three sub-models (agricultural area, groundwater zone, and channel network), allows us to describe water fluxes dynamics in rice areas at the irrigation district scale. Once calibrated for a 1000 ha district located in northern Italy using meteorological, hydrological and land-use data of a recent four-year period (2013–2016), the model was used to provide indications on the effects of different irrigation management options on district irrigation requirements, groundwater levels and irrigation/drainage network efficiency. Four scenarios considering a complete conversion of rice irrigation management over the district were implemented: WFL; DFL—dry seeding and delayed flooding; WDA—alternate wetting and drying; WFL-W—WFL followed by post-harvest winter flooding from 15 November to 15 January. Average results for the period 2013–2016 showed that DFL and WDA would lead to a reduction in summer irrigation needs compared to WFL, but also to a postponement of the peak irrigation month to June, already characterized by a strong water demand from other crops. Finally, summer irrigation consumption for WFL-W would correspond to WFL, suggesting that the considered winter flooding period ended too early to influence summer crop water needs. Full article

(This article belongs to the Special Issue Managing and Planning Water Resources for Irrigation: Smart Irrigation Systems for Providing Sustainable Agriculture and Maintaining Ecosystem Services)

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17 pages, 1437 KiB

Open AccessEditor’s ChoiceArticle

Crop Performance and Water Productivity of Transplanted Rice as Affected by Seedling Age and Seedling Density under Alternate Wetting and Drying Conditions in Lao PDR

by Rubenito Lampayan, Phetmanyseng Xangsayasane and Crisanta Bueno

Water 2019, 11(9), 1816; https://doi.org/10.3390/w11091816 - 31 Aug 2019

Cited by 8 | Viewed by 4562

Abstract

Drought is common under rainfed lowlands in Lao People’s Democratic Republic, and with the uncertain onset of rains during the wet season, delay in transplanting results in yield reduction. This study aims to explore ways to ameliorate the negative influence of delayed transplanting [...] Read more.

Drought is common under rainfed lowlands in Lao People’s Democratic Republic, and with the uncertain onset of rains during the wet season, delay in transplanting results in yield reduction. This study aims to explore ways to ameliorate the negative influence of delayed transplanting on rice crop. A field experiment was conducted for two wet seasons to investigate the effect of seedling age and seedling density on crop performance in terms of grain yield and water productivity. The experiment was laid out in a split–split plot design in four replicates, with seedling age as the main plot, seedling density as the subplot, and varieties as the sub-sub plot. In both years, there were significant seedling age and variety interactions on grain yield. Higher grain yields were observed with older seedlings having stronger tillering propensity. Seedling density did not affect grain yields in both years, but on grain yield components. Shorter duration variety received less supplemental irrigation than longer duration varieties. Late transplanting improved total water productivity but decreased irrigation water productivity due to harvesting delay. The total crop growth duration (from sowing to maturity) was prolonged with transplanting delay. However, the total stay of plants in the main field (from transplanting to maturity) was reduced by 3–5 d for every 10 d delay in transplanting. The results indicated that a good selection of varieties and increasing seedling density improve crop performance and water productivity with delayed transplanting. Full article

(This article belongs to the Special Issue Water Management for Sustainable Food Production)

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24 pages, 6102 KiB

Open AccessEditor’s ChoiceArticle

The Impact of Climate Change on Crop Production in Uganda—An Integrated Systems Assessment with Water and Energy Implications

by Vignesh Sridharan, Eunice Pereira Ramos, Eduardo Zepeda, Brent Boehlert, Abhishek Shivakumar, Constantinos Taliotis and Mark Howells

Water 2019, 11(9), 1805; https://doi.org/10.3390/w11091805 - 29 Aug 2019

Cited by 28 | Viewed by 10762

Abstract

With less than 3% of agricultural cropland under irrigation, subsistence farmers in Uganda are dependent on seasonal precipitation for crop production. The majority of crops grown in the country—especially staple food crops like Matooke (Plantains)—are sensitive to the availability of water throughout their [...] Read more.

With less than 3% of agricultural cropland under irrigation, subsistence farmers in Uganda are dependent on seasonal precipitation for crop production. The majority of crops grown in the country—especially staple food crops like Matooke (Plantains)—are sensitive to the availability of water throughout their growing period and hence vulnerable to climatic impacts. In response to these challenges, the Government has developed an ambitious irrigation master plan. However, the energy implications of implementing the plan have not been explored in detail. This article attempts to address three main issues involving the nexus between water, energy, crop production, and climate. The first one explores the impact of climate on rain-fed crop production. The second explores the irrigation crop water needs under selected climate scenarios. The third focuses on the energy implications of implementing the irrigation master plan. We attempt to answer the above questions using a water balance model for Uganda developed for this study. Our results, developed at a catchment level, indicate that on average there could be an 11% reduction and 8% increase in rain-fed crop production in the cumulatively driest and wettest climates, respectively. Furthermore, in the identified driest climate, the electricity required for pumping water is expected to increase by 12% on average compared to the base scenario. Full article

(This article belongs to the Special Issue Integrated Assessment of the Water–Energy–Land Nexus)

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36 pages, 1210 KiB

Open AccessEditor’s ChoiceReview

The Use of Algae and Fungi for Removal of Pharmaceuticals by Bioremediation and Biosorption Processes: A Review

by Andreia Silva, Cristina Delerue-Matos, Sónia A. Figueiredo and Olga M. Freitas

Water 2019, 11(8), 1555; https://doi.org/10.3390/w11081555 - 27 Jul 2019

Cited by 134 | Viewed by 18414

Abstract

The occurrence and fate of pharmaceuticals in the aquatic environment is recognized as one of the emerging issues in environmental chemistry. Conventional wastewater treatment plants (WWTPs) are not designed to remove pharmaceuticals (and their metabolites) from domestic wastewaters. The treatability of pharmaceutical compounds [...] Read more.

The occurrence and fate of pharmaceuticals in the aquatic environment is recognized as one of the emerging issues in environmental chemistry. Conventional wastewater treatment plants (WWTPs) are not designed to remove pharmaceuticals (and their metabolites) from domestic wastewaters. The treatability of pharmaceutical compounds in WWTPs varies considerably depending on the type of compound since their biodegradability can differ significantly. As a consequence, they may reach the aquatic environment, directly or by leaching of the sludge produced by these facilities. Currently, the technologies under research for the removal of pharmaceuticals, namely membrane technologies and advanced oxidation processes, have high operation costs related to energy and chemical consumption. When chemical reactions are involved, other aspects to consider include the formation of harmful reaction by-products and the management of the toxic sludge produced. Research is needed in order to develop economic and sustainable treatment processes, such as bioremediation and biosorption. The use of low-cost materials, such as biological matrices (e.g., algae and fungi), has advantages such as low capital investment, easy operation, low operation costs, and the non-formation of degradation by-products. An extensive review of existing research on this subject is presented. Full article

(This article belongs to the Special Issue Removal of Pharmaceuticals from Water: Conventional and Alternative Treatments)

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16 pages, 2762 KiB

Open AccessEditor’s ChoiceArticle

Increased Dependence on Irrigated Crop Production Across the CONUS (1945–2015)

by Samuel J. Smidt, Anthony D. Kendall and David W. Hyndman

Water 2019, 11(7), 1458; https://doi.org/10.3390/w11071458 - 14 Jul 2019

Cited by 11 | Viewed by 4132

Abstract

Efficient irrigation technologies, which seem to promise reduced production costs and water consumption in heavily irrigated areas, may instead be driving increased irrigation use in areas that were not traditionally irrigated. As a result, the total dependence on supplemental irrigation for crop production [...] Read more.

Efficient irrigation technologies, which seem to promise reduced production costs and water consumption in heavily irrigated areas, may instead be driving increased irrigation use in areas that were not traditionally irrigated. As a result, the total dependence on supplemental irrigation for crop production and revenue is steadily increasing across the contiguous United States. Quantifying this dependence has been hampered by a lack of comprehensive irrigated and dryland yield and harvested area data outside of major irrigated regions, despite the importance and long history of irrigation applications in agriculture. This study used a linear regression model to disaggregate lumped agricultural statistics and estimate average irrigated and dryland yields at the state level for five major row crops: corn, cotton, hay, soybeans, and wheat. For 1945–2015, we quantified crop production, irrigation enhancement revenue, and irrigated and dryland areas in both intensively irrigated and marginally-dependent states, where both irrigated and dryland farming practices are implemented. In 2015, we found that irrigating just the five commodity crops enhanced revenue by ~$7 billion across all states with irrigation. In states with both irrigated and dryland practices, 23% of total produced area relied on irrigation, resulting in 7% more production than from dryland practices. There was a clear response to increasing biofuel demand, with the addition of more than 3.6 million ha of irrigated corn and soybeans in the last decade in marginally-dependent states. Since 1945, we estimate that yield enhancement due to irrigation has resulted in over $465 billion in increased revenue across the contiguous United States (CONUS). Example applications of this dataset include estimating historical water use, evaluating the effects of environmental policies, developing new resource management strategies, economic risk analyses, and developing tools for farmer decision making. Full article

(This article belongs to the Special Issue Precision Agriculture and Irrigation)

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Graphical abstract

21 pages, 4609 KiB

Open AccessEditor’s ChoiceArticle

Adaptation Effort and Performance of Water Management Strategies to Face Climate Change Impacts in Six Representative Basins of Southern Europe

by Alvaro Sordo-Ward, Alfredo Granados, Ana Iglesias, Luis Garrote and María Dolores Bejarano

Water 2019, 11(5), 1078; https://doi.org/10.3390/w11051078 - 23 May 2019

Cited by 31 | Viewed by 4607

Abstract

We evaluated different management alternatives to enhance potential water availability for agriculture under climate change scenarios. The management goal involved maximizing potential water availability, understood as the maximum volume of water supplied at a certain point of the river network that satisfies a [...] Read more.

We evaluated different management alternatives to enhance potential water availability for agriculture under climate change scenarios. The management goal involved maximizing potential water availability, understood as the maximum volume of water supplied at a certain point of the river network that satisfies a defined demand, and taking into account specified reliability requirements. We focused on potential water availability for agriculture and assumed two types of demands: urban supply and irrigation. If potential water availability was not enough to satisfy all irrigation demands, management measures were applied aiming at achieving a compromise solution between resources and demands. The methodological approach consisted of estimation and comparison of runoff for current and future period under climate change effects, calculation of water availability changes due to changes in runoff, and evaluation of the adaptation choices that can modify the distribution of water availability, under climate change. Adaptation choices include modifying water allocation to agriculture, increasing the reservoir storage capacity, improving the efficiency of urban water use, and modifying water allocation to environmental flows. These management measures were evaluated at the desired points of the river network by applying the Water Availability and Adaptation Policy Analysis (WAAPA) model. We simulated the behavior of a set of reservoirs that supply water for a set of prioritized demands, complying with specified ecological flows and accounting for evaporation losses. We applied the methodology in six representative basins of southern Europe: Duero-Douro, Ebro, Guadalquivir, Po, Maritsa-Evros, and Struma-Strymon. While in some basins, such as the Ebro or Struma-Strymon, measures can significantly increase water availability and compensate for a fraction of water scarcity due to climate change, in other basins, like the Guadalquivir, water availability cannot be enhanced by applying the management measures analyzed, and irrigation water use will have to be reduced. Full article

(This article belongs to the Special Issue Hydrological and Hydro-Meteorological Extremes and Related Risk and Uncertainty)

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