Water

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Open AccessEditorial

Acknowledgement to Reviewers of Water in 2015

by Water Editorial Office

Water 2016, 8(1), 33; https://doi.org/10.3390/w8010033 - 21 Jan 2016

Viewed by 4584

The editors of Water would like to express their sincere gratitude to the following reviewers for assessing manuscripts in 2015. [...] Full article

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Open AccessArticle

Spatial and Temporal Distribution of Soil Moisture at the Catchment Scale Using Remotely-Sensed Energy Fluxes

by Thomas K. Alexandridis, Ines Cherif, George Bilas, Waldenio G. Almeida, Isnaeni M. Hartanto, Schalk Jan Van Andel and Antonio Araujo

Water 2016, 8(1), 32; https://doi.org/10.3390/w8010032 - 21 Jan 2016

Cited by 18 | Viewed by 7072

Abstract

Despite playing a critical role in the division of precipitation between runoff and infiltration, soil moisture (SM) is difficult to estimate at the catchment scale and at frequent time steps, as is required by many hydrological, erosion and flood simulation models. In this [...] Read more.

Despite playing a critical role in the division of precipitation between runoff and infiltration, soil moisture (SM) is difficult to estimate at the catchment scale and at frequent time steps, as is required by many hydrological, erosion and flood simulation models. In this work, an integrated methodology is described to estimate SM at the root zone, based on the remotely-sensed evaporative fraction (Λ) and ancillary information on soil and meteorology. A time series of Terra MODIS satellite images was used to estimate SM maps with an eight-day time step at a 250-m spatial resolution for three diverse catchments in Europe. The study of the resulting SM maps shows that their spatial variability follows the pattern of land cover types and the main geomorphological features of the catchment, and their temporal pattern follows the distribution of rain events, with the exception of irrigated land. Field surveys provided in situ measurements to validate the SM maps’ accuracy, which proved to be variable according to site and season. In addition, several factors were analyzed in order to explain the variation in the accuracy, and it was shown that the land cover type, the soil texture class, the temporal difference between the datasets’ acquisition and the presence of rain events during the measurements played a significant role, rather than the often referred to scale difference between in situ and satellite observations. Therefore, the proposed methodology can be used operationally to estimate SM maps at the catchment scale, with a 250-m spatial resolution and an eight-day time step. Full article

(This article belongs to the Special Issue Remote Sensing of Soil Moisture)

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3265 KiB

Open AccessArticle

Effects of the “Run-of-River” Hydro Scheme on Macroinvertebrate Communities and Habitat Conditions in a Mountain River of Northeastern China

by Haoran Wang, Yongcan Chen, Zhaowei Liu and Dejun Zhu

Water 2016, 8(1), 31; https://doi.org/10.3390/w8010031 - 21 Jan 2016

Cited by 25 | Viewed by 6379

Abstract

The main objective of this study was to quantify the impacts of the run of river (ROR) scheme on the instream habitat and macroinvertebrate community. We sampled the macroinvertebrate assemblages and collected the habitat variables above and below an ROR hydropower plant: Aotou [...] Read more.

The main objective of this study was to quantify the impacts of the run of river (ROR) scheme on the instream habitat and macroinvertebrate community. We sampled the macroinvertebrate assemblages and collected the habitat variables above and below an ROR hydropower plant: Aotou plant in the Hailang River, China. The effects of the ROR scheme on habitat conditions were examined using regulation-related variables, most of which, particularly the hydrological variables and substrate composition, presented spatial variations along the downstream direction, contributing to heterogeneous conditions between reaches. The macroinvertebrate richness, the density and the diversity metrics showed significant decreases in the “depleted” reach compared with the upper and lower reaches. Approximately 75% of reach-averaged densities and 50% of taxa richness suffered decreases in the “depleted” reach compared with the upper reach. Furthermore, functional feeding groups also showed distinct site differences along the channel. The relative abundance of both collector-gatherers and the scrapers reduced considerably at the “depleted” sites, particularly at the site immediately downstream of the weir. The total variance in the the functional feeding group (FFG) data explained by Canonical correlation analysis (CCA) was more than 81.4% and the high-loadings factors were depth, flow velocity, DO and substrate composition. We demonstrated that flow diversion at the 75% level and an in-channel barrier, due to the ROR scheme, are likely to lead to poor habitat conditions and decrease both the abundance and the diversity of macroinvertebrates in reaches influenced by water diversion. Full article

(This article belongs to the Special Issue Ecological Monitoring, Assessment, and Management in Freshwater Systems)

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Open AccessReview

Rain Drop Measurement Techniques: A Review

by Gopinath Kathiravelu, Terry Lucke and Peter Nichols

Water 2016, 8(1), 29; https://doi.org/10.3390/w8010029 - 21 Jan 2016

Cited by 117 | Viewed by 23294

Abstract

For over a century there have been many studies that describe the use of rain drop measurement techniques. Initial manual measurement methods evolved due to improved technology to include photographic and, more recently, automated disdrometer and laser measurement techniques. Despite these numerous studies, [...] Read more.

For over a century there have been many studies that describe the use of rain drop measurement techniques. Initial manual measurement methods evolved due to improved technology to include photographic and, more recently, automated disdrometer and laser measurement techniques. Despite these numerous studies, there have been few comparative reviews of the range of methodologies, and their relative performance. This review explores the raindrop measurement techniques available, and summarizes and classifies the techniques according to the method or principle involved. The requirements of a robust raindrop measurement technique are suggested, and these are reviewed against existing rain drop measurement techniques to provide a comparative guide to the use of the range of techniques available for any research study. This review revealed that while advances in technology have allowed many of the deficiencies of early techniques to be eliminated, challenges remain in relation to the precision of the measurement of the size, shape, and velocity of rain drops. Full article

(This article belongs to the Special Issue Urban Drainage and Urban Stormwater Management)

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Open AccessArticle

Anthropogenic Nitrogen and Phosphorus Emissions and Related Grey Water Footprints Caused by EU-27′s Crop Production and Consumption

by Mesfin M. Mekonnen, Stephan Lutter and Aldo Martinez

Water 2016, 8(1), 30; https://doi.org/10.3390/w8010030 - 20 Jan 2016

Cited by 35 | Viewed by 8926

Abstract

Water is a prerequisite for life on our planet. Due to climate change and pollution, water availability for agricultural production, industry and households is increasingly put at risk. With agriculture being the largest water user as well as polluter worldwide, we estimate anthropogenic [...] Read more.

Water is a prerequisite for life on our planet. Due to climate change and pollution, water availability for agricultural production, industry and households is increasingly put at risk. With agriculture being the largest water user as well as polluter worldwide, we estimate anthropogenic nitrogen and phosphorus emissions to fresh water related to global crop production at a spatial resolution level of 5 by 5 arc min and calculate the grey water footprints (GWF) related to EU-27′s crop production. A multiregional input-output model is used to trace the the GWF embodied in the final consumption of crop products by the EU-27. The total GWF related to crop production in the EU-27 in 2007 was 1 × 10¹² m³/year. Spain contributed about 40% to this total. Production of cereals (wheat, rice and other cereals) take the largest share, accounting for 30% of the GWF, followed by fruits (17%), vegetables (14%), and oil crops (13%). The total agricultural GWF of the EU-27 related to crop consumption was 1830 billion m³/year, which is 3700 m³/year per capita on average. Overall, the EU-27 was able to externalize about 41% of the GWF to the rest of the world through imports of crop products. Full article

(This article belongs to the Special Issue Processes Governing Transport of Nutrients from Terrestrial to Aquatic Environment and Inferred Abatement)

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Open AccessArticle

Extraction and Preference Ordering of Multireservoir Water Supply Rules in Dry Years

by Ling Kang, Song Zhang, Yi Ding and Xiaocong He

Water 2016, 8(1), 28; https://doi.org/10.3390/w8010028 - 20 Jan 2016

Cited by 18 | Viewed by 6583

Abstract

This paper presents a new methodology of combined use of the nondominated sorting genetic algorithm II (NSGA-II) and the approach of successive elimination of alternatives based on order and degree of efficiency (SEABODE) in identifying the most preferred multireservoir water supply rules in [...] Read more.

This paper presents a new methodology of combined use of the nondominated sorting genetic algorithm II (NSGA-II) and the approach of successive elimination of alternatives based on order and degree of efficiency (SEABODE) in identifying the most preferred multireservoir water supply rules in dry years. First, the suggested operation rules consists of a two-point type time-varying hedging policy for a single reservoir and a simple proportional allocation policy of common water demand between two parallel reservoirs. Then, the NSGA-II is employed to derive enough noninferior operation rules (design alternatives) in terms of two conflicting objectives (1) minimizing the total deficit ratio (TDR) of all demands of the entire system in operation horizon, and (2) minimizing the maximum deficit ratio (MDR) of water supply in a single period. Next, the SEABODE, a multicriteria decision making (MCDM) procedure, is applied to further eliminate alternatives based on the concept of efficiency of order k with degree p. In SEABODE, the reservoir performance indices and water shortage indices are selected as evaluation criteria for preference ordering among the design alternatives obtained by NSGA-II. The proposed methodology was tested on a regional water supply system with three reservoirs located in the Jialing River, China, where the results demonstrate its applicability and merits. Full article

(This article belongs to the Collection Water Policy Collection)

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Open AccessArticle

Spatial Distribution of Benthic Macroinvertebrate Assemblages in Relation to Environmental Variables in Korean Nationwide Streams

by Yung-Chul Jun, Nan-Young Kim, Sang-Hun Kim, Young-Seuk Park, Dong-Soo Kong and Soon-Jin Hwang

Water 2016, 8(1), 27; https://doi.org/10.3390/w8010027 - 20 Jan 2016

Cited by 53 | Viewed by 8359

Abstract

Conserving and enhancing freshwater biodiversity are global issues to ensure ecosystem integrity and sustainability. To meet this, it is critical to understand how the biological assemblages are determined by environmental gradients in different spatial scales. Nevertheless, information on their large-scale environmental relationships remains [...] Read more.

Conserving and enhancing freshwater biodiversity are global issues to ensure ecosystem integrity and sustainability. To meet this, it is critical to understand how the biological assemblages are determined by environmental gradients in different spatial scales. Nevertheless, information on their large-scale environmental relationships remains scarce in Korea. We aimed to understand nationwide spatial distribution patterns of benthic macroinvertebrates and important environmental factors affecting their distribution in 388 streams and rivers across Korea. A total of 340 taxa, belonging to 113 families in 23 orders of five phyla, were identified. Assemblage composition in most Korean streams included a few predominant colonizers and a majority of rare taxa. Cluster analysis based on benthic macroinvertebrates classified a total of 720 sampling sites into five clusters according to the pollution levels from fast-flowing less polluted streams with low electrical conductivity to moderately or severely polluted streams with high electrical conductivity and slow water velocity. Canonical correspondence analysis revealed that altitude, water velocity and streambed composition were the most important determinants, rather than watershed and water chemistry variables, for explaining the variation in macroinvertebrate assemblage patterns. The results provide basic information for establishing the conservation and restoration strategies of macroinvertebrate biodiversity against anthropogenic disturbances and developing more confident bio-assessment tools for diagnosing stream ecosystem integrity. Full article

(This article belongs to the Special Issue Ecological Monitoring, Assessment, and Management in Freshwater Systems)

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Open AccessArticle

Implications of Texture and Erodibility for Sediment Retention in Receiving Basins of Coastal Louisiana Diversions

by Kehui Xu, Samuel J. Bentley, Patrick Robichaux, Xiaoyu Sha and Haifei Yang

Water 2016, 8(1), 26; https://doi.org/10.3390/w8010026 - 20 Jan 2016

Cited by 44 | Viewed by 8764

Abstract

Although the Mississippi River deltaic plain has been the subject of abundant research over recent decades, there is a paucity of data concerning field measurement of sediment erodibility in Louisiana estuaries. Two contrasting receiving basins for active diversions were studied: West Bay on [...] Read more.

Although the Mississippi River deltaic plain has been the subject of abundant research over recent decades, there is a paucity of data concerning field measurement of sediment erodibility in Louisiana estuaries. Two contrasting receiving basins for active diversions were studied: West Bay on the western part of Mississippi River Delta and Big Mar, which is the receiving basin for the Caernarvon freshwater diversion. Push cores and water samples were collected at six stations in West Bay and six stations in Big Mar. The average erodibility of Big Mar sediment was similar to that of Louisiana shelf sediment, but was higher than that of West Bay. Critical shear stress to suspend sediment in both West Bay and Big Mar receiving basins was around 0.2 Pa. A synthesis of 1191 laser grain size data from surficial and down-core sediment reveals that silt (4–63 μm) is the largest fraction of retained sediment in receiving basins, larger than the total of sand (>63 μm) and clay (<4 μm). It is suggested that preferential delivery of fine grained sediment to more landward and protected receiving basins would enhance mud retention. In addition, small fetch sizes and fragmentation of large receiving basins are favorable for sediment retention. Full article

(This article belongs to the Special Issue Resilience and Sustainability of the Mississippi River Delta as a Coupled Natural-Human System)

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Open AccessArticle

Hydraulic Transients Caused by Air Expulsion During Rapid Filling of Undulating Pipelines

by Ciro Apollonio, Gabriella Balacco, Nicola Fontana, Maurizio Giugni, Gustavo Marini and Alberto Ferruccio Piccinni

Water 2016, 8(1), 25; https://doi.org/10.3390/w8010025 - 19 Jan 2016

Cited by 46 | Viewed by 6300

Abstract

One of the main issues arising during the rapid filling of a pipeline is the pressure transient which originates after the entrapped air has been expelled at the air release valve. Because of the difference in density between water and air, a pressure [...] Read more.

One of the main issues arising during the rapid filling of a pipeline is the pressure transient which originates after the entrapped air has been expelled at the air release valve. Because of the difference in density between water and air, a pressure transient originates at the impact of the water column. Many authors have analyzed the problem, both from the theoretical and the experimental standpoint. Nevertheless, mainly vertical or horizontal pipelines have been analyzed, whereas in real field applications, the pipe profile is a sequence of ascending and descending pipes, with air release/vacuum valves at high points. To overcome lack of knowledge regarding this latter case, laboratory experiments were carried out to simulate the filling of an undulating pipeline, initially empty at atmospheric pressure. The pipe profile has a high point where an orifice is installed for air venting, so as to simulate the air release valve at intermediate high point of a supply pipeline. In the experiments, the diameter of the orifice and the opening degree of both upstream and downstream valves were varied, in order to analyze their effect on the pressure transient. The experiments were also carried out with a longer descending pipe, in order to assess the effects on the pressure surge of the air volume downstream of the orifice. Full article

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Open AccessArticle

New Insights on the Simultaneous Removal by Adsorption on Organoclays of Humic Acid and Phenol

by Emese Szabó, Zsolt Pap, Gergő Simon, András Dombi, Lucian Baia and Klára Hernádi

Water 2016, 8(1), 21; https://doi.org/10.3390/w8010021 - 18 Jan 2016

Cited by 5 | Viewed by 5538

Abstract

The exploitation of thermal water as a heat source in houses and apartments (during winter) is a widely used alternative to natural gas. However, this type of water may contain organic contaminants, which must be removed before releasing the used water into rivers [...] Read more.

The exploitation of thermal water as a heat source in houses and apartments (during winter) is a widely used alternative to natural gas. However, this type of water may contain organic contaminants, which must be removed before releasing the used water into rivers and lakes. Because of the presence of a wide range of pollutants (including phenolic compounds and humates), efficient, cheap removal processes are needed. In order to demonstrate their capability in thermal water cleaning, clay minerals were applied for the removal of phenol and humic acid via adsorption. To determine the most efficient removal strategy for the aforementioned pollutants, the following parameters were investigated: the type of the clay mineral, the organophilization strategy (in situ or pre-organophilization), and the individual or simultaneous removability of the model pollutants. The current study revealed that the applied low cost, in situ prepared clay mineral adsorbents are applicable in the removal of pollutants from thermal water. Full article

(This article belongs to the Special Issue Groundwater Monitoring and Remediation)

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Open AccessArticle

Effect of Plant Harvesting on the Performance of Constructed Wetlands during Summer

by Zhongchen Yang, Qian Wang, Jian Zhang, Huijun Xie and Suping Feng

Water 2016, 8(1), 24; https://doi.org/10.3390/w8010024 - 16 Jan 2016

Cited by 33 | Viewed by 6231

Abstract

Plants can remove pollutants through direct absorption and by providing habitats for microbes to stimulate their activities. The aboveground plant biomass is usually harvested to remove pollutants absorbed in plant tissues. However, the effect of plant harvesting during summer on the performance of [...] Read more.

Plants can remove pollutants through direct absorption and by providing habitats for microbes to stimulate their activities. The aboveground plant biomass is usually harvested to remove pollutants absorbed in plant tissues. However, the effect of plant harvesting during summer on the performance of constructed wetlands and microbial abundance is unclear. In this study, three types of microcosms were set up, including: cleared group (both shoots and roots were harvested), harvested group (only shoots were harvested) and unharvested group. The concentrations of ammonia nitrogen and chemical oxygen demand in the effluent of the harvested group were the lowest. The nitrogen mass balance showed that summer harvesting improved nitrogen absorbance by plants, which was 1.24-times higher than that in the unharvested group. Interestingly, the other losses were taken up by the highest amounts in the cleared group, which were 1.66- and 3.72-times higher than in the unharvested and harvested group, respectively. Quantitative polymerase chain reaction revealed that harvesting of shoots during summer increased the microbial abundance. Additionally, Proteobacteria was the dominant phylum among all bacteria according to pyrosequencing analysis. These results indicate that harvesting of shoots during summer has positive effects on pollutant removal and microbial abundance. Full article

(This article belongs to the Special Issue Constructed Wetlands Systems and Management)

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Open AccessArticle

Potential Impacts of Climate Change on Water Resources in the Kunhar River Basin, Pakistan

by Rashid Mahmood, Shaofeng Jia and Mukand S. Babel

Water 2016, 8(1), 23; https://doi.org/10.3390/w8010023 - 16 Jan 2016

Cited by 74 | Viewed by 14453

Abstract

Pakistan is one of the most highly water-stressed countries in the world and its water resources are greatly vulnerable to changing climatic conditions. The present study investigates the possible impacts of climate change on the water resources of the Kunhar River basin, Pakistan, [...] Read more.

Pakistan is one of the most highly water-stressed countries in the world and its water resources are greatly vulnerable to changing climatic conditions. The present study investigates the possible impacts of climate change on the water resources of the Kunhar River basin, Pakistan, under A2 and B2 scenarios of HadCM3, a global climate model. After successful development of the hydrological modeling system (HEC-HMS) for the basin, streamflow was simulated for three future periods (2011–2040, 2041–2070, and 2071–2099) and compared with the baseline period (1961–1990) to explore the changes in different flow indicators such as mean flow, low flow, median flow, high flow, flow duration curves, temporal shift in peaks, and temporal shifts in center-of-volume dates. From the results obtained, an overall increase in mean annual flow was projected in the basin under both A2 and B2 scenarios. However, while summer and autumn showed a noticeable increase in streamflow, spring and winter showed decreased streamflow. High and median flows were predicted to increase, but low flow was projected to decrease in the future under both scenarios. Flow duration curves showed that the probability of occurrence of flow is likely to be more in the future. It was also noted that peaks were predicted to shift from June to July in the future, and the center-of-volume date—the date at which half of the annual flow passes—will be delayed by about 9–17 days in the basin, under both A2 and B2 scenarios. On the whole, the Kunhar basin will face more floods and droughts in the future due to the projected increase in high flow and decrease in low flow and greater temporal and magnitudinal variations in peak flows. These results highlight how important it is to take cognizance of the impact of climate change on water resources in the basin and to formulate suitable policies for the proper utilization and management of these resources. Full article

(This article belongs to the Special Issue Water Resource Variability and Climate Change)

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Open AccessArticle

Roles of N:P Ratios on Trophic Structures and Ecological Stream Health in Lotic Ecosystems

by Young-Jin Yun and Kwang-Guk An

Water 2016, 8(1), 22; https://doi.org/10.3390/w8010022 - 16 Jan 2016

Cited by 16 | Viewed by 9774

Abstract

Little is known about the functions of N:P ratios in determining trophic structures and ecological health in lotic ecosystems, even though N:P ratios have been frequently used as a stoichiometric determinant in ambient water for trophic allocation of low-level organisms such as phytoplankton [...] Read more.

Little is known about the functions of N:P ratios in determining trophic structures and ecological health in lotic ecosystems, even though N:P ratios have been frequently used as a stoichiometric determinant in ambient water for trophic allocation of low-level organisms such as phytoplankton or zooplankton. In this study, nutrients (N, P) and sestonic chlorophyll (CHL) from 40 different streams in the Geum-River watershed were measured from 2008 to 2011. Fish compositions and stream health were also assessed, based on the multi-metric modeling of an index of biological integrity. Land use patterns in these watersheds were a key factor regulating nutrient contents and N:P ratios in ambient water, and also influenced empirical relationships between N:P ratios (or nutrients) and sestonic CHL. Land use patterns in forested, urban and wastewater treatment plant regions were associated with significant differences in stream N:P ratios, and the ratios were mainly determined by phosphorus. Sestonic CHL was significantly correlated with nutrient level (N, P); the ratios had a positive linear relationship with the proportion of omnivores, and a negative relationship with the proportion of insectivores. A similar trend in the N:P ratios was observed in indicator fishes such as N. koreanus and Z. platypus. Overall, the N:P ratio may be a good surrogate variable of ambient concentrations of N or P in assessing trophic linkage and diagnosing the ecological stream health in aquatic ecosystems. Full article

(This article belongs to the Special Issue Ecological Monitoring, Assessment, and Management in Freshwater Systems)

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Open AccessArticle

A CN-Based Ensembled Hydrological Model for Enhanced Watershed Runoff Prediction

by Muhammad Ajmal, Taj Ali Khan and Tae-Woong Kim

Water 2016, 8(1), 20; https://doi.org/10.3390/w8010020 - 15 Jan 2016

Cited by 18 | Viewed by 6106

Abstract

A major structural inconsistency of the traditional curve number (CN) model is its dependence on an unstable fixed initial abstraction, which normally results in sudden jumps in runoff estimation. Likewise, the lack of pre-storm soil moisture accounting (PSMA) procedure is another inherent limitation [...] Read more.

A major structural inconsistency of the traditional curve number (CN) model is its dependence on an unstable fixed initial abstraction, which normally results in sudden jumps in runoff estimation. Likewise, the lack of pre-storm soil moisture accounting (PSMA) procedure is another inherent limitation of the model. To circumvent those problems, we used a variable initial abstraction after ensembling the traditional CN model and a French four-parameter (GR4J) model to better quantify direct runoff from ungauged watersheds. To mimic the natural rainfall-runoff transformation at the watershed scale, our new parameterization designates intrinsic parameters and uses a simple structure. It exhibited more accurate and consistent results than earlier methods in evaluating data from 39 forest-dominated watersheds, both for small and large watersheds. In addition, based on different performance evaluation indicators, the runoff reproduction results show that the proposed model produced more consistent results for dry, normal, and wet watershed conditions than the other models used in this study. Full article

(This article belongs to the Special Issue Use of Meta-Heuristic Techniques in Rainfall-Runoff Modelling)

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Open AccessArticle

Tracing Temporal Changes of Model Parameters in Rainfall-Runoff Modeling via a Real-Time Data Assimilation

by Shanshan Meng, Xianhong Xie and Xiao Yu

Water 2016, 8(1), 19; https://doi.org/10.3390/w8010019 - 11 Jan 2016

Cited by 13 | Viewed by 5479

Abstract

Watershed characteristics such as patterns of land use and land cover (LULC), soil structure and river systems, have substantially changed due to natural and anthropogenic factors. To adapt hydrological models to the changing characteristics of watersheds, one of the feasible strategies is to [...] Read more.

Watershed characteristics such as patterns of land use and land cover (LULC), soil structure and river systems, have substantially changed due to natural and anthropogenic factors. To adapt hydrological models to the changing characteristics of watersheds, one of the feasible strategies is to explicitly estimate the changed parameters. However, few approaches have been dedicated to these non-stationary conditions. In this study, we employ an ensemble Kalman filter (EnKF) technique with a constrained parameter evolution scheme to trace the parameter changes. This technique is coupled to a rainfall-runoff model, i.e., the Xinanjiang (XAJ) model. In addition to a stationary condition, we designed three typical non-stationary conditions, including sudden, gradual and rotational changes with respect to two behavioral parameters of the XAJ. Synthetic experiments demonstrated that the EnKF-based method can trace the three types of parameter changes in real time. This method shows robust performance even for the scenarios of high-level uncertainties within rainfall input, modeling and observations, and it holds an implication for detecting changes in watershed characteristics. Coupling this method with a rainfall-runoff model is useful to adapt the model to non-stationary conditions, thereby improving flood simulations and predictions. Full article

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Open AccessArticle

A Reliability Analysis of a Rainfall Harvesting System in Southern Italy

by Lorena Liuzzo, Vincenza Notaro and Gabriele Freni

Water 2016, 8(1), 18; https://doi.org/10.3390/w8010018 - 8 Jan 2016

Cited by 52 | Viewed by 9974

Abstract

Rainwater harvesting (RWH) may be an effective alternative water supply solution in regions affected by water scarcity. It has recently become a particularly important option in arid and semi-arid areas (like Mediterranean basins), mostly because of its many benefits and affordable costs. This [...] Read more.

Rainwater harvesting (RWH) may be an effective alternative water supply solution in regions affected by water scarcity. It has recently become a particularly important option in arid and semi-arid areas (like Mediterranean basins), mostly because of its many benefits and affordable costs. This study provides an analysis of the reliability of using a rainwater harvesting system to supply water for toilet flushing and garden irrigation purposes, with reference to a single-family home in a residential area of Sicily (Southern Italy). A flushing water demand pattern was evaluated using water consumption data collected from a sample of residential customers during an extended measurement campaign. A daily water balance simulation of the rainwater storage tank was performed, and the yield-after-spillage algorithm was used to define the tank release rule. The model’s performance was evaluated using rainfall data from more than 100 different sites located throughout the Sicilian territory. This regional analysis provided annual reliability curves for the system as a function of mean annual precipitation, which have practical applications in this area of study. The uncertainty related to the regional model predictions was also assessed. A cost-benefit analysis highlighted that the implementation of a rainwater harvesting system in Sicily can provide environmental and economic advantages over traditional water supply methods. In particular, the regional analysis identified areas where the application of this system would be most effective. Full article

(This article belongs to the Special Issue Rainwater Harvesting: Quantity, Quality, Economics and State Regulations)

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Open AccessArticle

The Effect of Particle Size Distribution on the Design of Urban Stormwater Control Measures

by Willliam R. Selbig, Michael N. Fienen, Judy A. Horwatich and Roger T. Bannerman

Water 2016, 8(1), 17; https://doi.org/10.3390/w8010017 - 6 Jan 2016

Cited by 27 | Viewed by 8146

Abstract

An urban pollutant loading model was used to demonstrate how incorrect assumptions on the particle size distribution (PSD) in urban runoff can alter the design characteristics of stormwater control measures (SCMs) used to remove solids in stormwater. Field-measured PSD, although highly variable, is [...] Read more.

An urban pollutant loading model was used to demonstrate how incorrect assumptions on the particle size distribution (PSD) in urban runoff can alter the design characteristics of stormwater control measures (SCMs) used to remove solids in stormwater. Field-measured PSD, although highly variable, is generally coarser than the widely-accepted PSD characterized by the Nationwide Urban Runoff Program (NURP). PSDs can be predicted based on environmental surrogate data. There were no appreciable differences in predicted PSD when grouped by season. Model simulations of a wet detention pond and catch basin showed a much smaller surface area is needed to achieve the same level of solids removal using the median value of field-measured PSD as compared to NURP PSD. Therefore, SCMs that used the NURP PSD in the design process could be unnecessarily oversized. The median of measured PSDs, although more site-specific than NURP PSDs, could still misrepresent the efficiency of an SCM because it may not adequately capture the variability of individual runoff events. Future pollutant loading models may account for this variability through regression with environmental surrogates, but until then, without proper site characterization, the adoption of a single PSD to represent all runoff conditions may result in SCMs that are under- or over-sized, rendering them ineffective or unnecessarily costly. Full article

(This article belongs to the Special Issue BMP Development, Implementation, and Performance)

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Open AccessArticle

Using a Modified Lane’s Relation in Local Bed Scouring Studies in the Laboratory Channel

by Marta Kiraga and Zbigniew Popek

Water 2016, 8(1), 16; https://doi.org/10.3390/w8010016 - 6 Jan 2016

Cited by 5 | Viewed by 6146

Abstract

Numerous approaches to local scour forming studies have been developed. This paper presents different scientific approaches to the scour phenomenon using Lane’s relation [1] in its modified form during laboratory studies. The original Lane’s relation is applicable in dynamic balance conditions in alluvial [...] Read more.

Numerous approaches to local scour forming studies have been developed. This paper presents different scientific approaches to the scour phenomenon using Lane’s relation [1] in its modified form during laboratory studies. The original Lane’s relation is applicable in dynamic balance conditions in alluvial rivers context, and it is not an equation, but a qualitative expression which cannot be directly used to estimate the influence of a change in one parameter on the magnitude of others. Lane's relation, despite its qualitative and simplified character, serves well to describe the nature of the process of forming alluvial stream channels, while modified relation allows transforming it into an equation for laboratory studies of local scour forming in prearranged clear-water equilibrium conditions and gives a new opportunity for this principle application. Full article

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Open AccessArticle

CO₂ is Dominant Greenhouse Gas Emitted from Six Hydropower Reservoirs in Southeastern United States during Peak Summer Emissions

by Mark S. Bevelhimer, Arthur J. Stewart, Allison M. Fortner, Jana R. Phillips and Jennifer J. Mosher

Water 2016, 8(1), 15; https://doi.org/10.3390/w8010015 - 6 Jan 2016

Cited by 19 | Viewed by 6338

Abstract

During August–September 2012, we sampled six hydropower reservoirs in southeastern United States for CO₂ and CH₄ emissions via three pathways: diffusive emissions from water surface; ebullition in the water column; and losses from dam tailwaters during power generation. Estimates of average [...] Read more.

During August–September 2012, we sampled six hydropower reservoirs in southeastern United States for CO₂ and CH₄ emissions via three pathways: diffusive emissions from water surface; ebullition in the water column; and losses from dam tailwaters during power generation. Estimates of average areal emission rates of CO₂ attributable to the six reservoirs (i.e., reservoir plus tailwater emissions) ranged from 994 to 2760 mg·m⁻²·day⁻¹, which is low to moderate compared to CO₂ emissions rates reported for tropical hydropower reservoirs and boreal ponds and lakes, and similar to rates reported for other temperate reservoirs. Similar average rates for CH₄ were also relatively low, ranging from 6 to 187 mg·m⁻²·day⁻¹. On a whole-reservoir basis, estimates of total emissions of CO₂ ranged 10-fold, from 42,740 kg per day for Fontana to 501,151 kg per day for Guntersville, and total emissions of CH₄ ranged over 30-fold, from 251 kg per day for Fontana to 9153 kg per day for Allatoona. Emissions through the tailwater pathway varied among reservoirs, comprising from 19% to 65% of total CO₂ emissions and 0% to 84% of CH₄ emissions, depending on the reservoir. Emission rates were significantly correlated with several reservoir morphological and water quality characteristics, including metrics related to vertical stratification (e.g., minimum water column temperature and maximum dissolved oxygen) and reservoir productivity (e.g., water transparency and chlorophyll a concentration). Full article

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1403 KiB

Open AccessArticle

Quantifying Rainfall Interception Loss of a Subtropical Broadleaved Forest in Central Taiwan

by Yi-Ying Chen and Ming-Hsu Li

Water 2016, 8(1), 14; https://doi.org/10.3390/w8010014 - 2 Jan 2016

Cited by 26 | Viewed by 7435

Abstract

The factors controlling seasonal rainfall interception loss are investigated by using a double-mass curve analysis, based on direct measurements of high-temporal resolution gross rainfall, throughfall and stemflow from 43 rainfall events that occurred in central Taiwan from April 2008 to April 2009. The [...] Read more.

The factors controlling seasonal rainfall interception loss are investigated by using a double-mass curve analysis, based on direct measurements of high-temporal resolution gross rainfall, throughfall and stemflow from 43 rainfall events that occurred in central Taiwan from April 2008 to April 2009. The canopy water storage capacity for the wet season was estimated to be 1.86 mm, about twice that for the dry season (0.91 mm), likely due to the large reduction in the leaf area index (LAI) from 4.63 to 2.23 (m²·m⁻²). Changes in seasonal canopy structure and micro-meteorological conditions resulted in temporal variations in the amount of interception components, and rainfall partitioning into stemflow and throughfall. Wet canopy evaporation after rainfall contributed 41.8% of the wet season interception loss, but only 17.1% of the dry season interception loss. Wet canopy evaporation during rainfall accounted for 82.9% of the dry season interception loss, but only 58.2% of the wet season interception loss. Throughfall accounted for over 79.7% of the dry season precipitation and 76.1% of the wet season precipitation, possibly due to the change in gap fraction from 64.2% in the dry season to 50.0% in the wet season. The reduced canopy cover in the dry season also produced less stemflow than that of the wet season. The rainfall stemflow ratio ( P s f / P g ) was reduced from 12.6% to 8.9%. Despite relatively large changes in canopy structure, seasonal variation of the ratio of rainfall partitioned to interception was quite small. Rainfall interception loss accounted for nearly 12% of gross precipitation for both dry and wet seasons. Full article

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5015 KiB

Open AccessArticle

The Acoustic Properties of Suspended Sediment in Large Rivers: Consequences on ADCP Methods Applicability

by Massimo Guerrero, Nils Rüther, Ricardo Szupiany, Stefan Haun, Sandor Baranya and Francisco Latosinski

Water 2016, 8(1), 13; https://doi.org/10.3390/w8010013 - 2 Jan 2016

Cited by 51 | Viewed by 9173

Abstract

The use of echo-levels from Acoustic Doppler Current Profiler (ADCP) recordings has become more and more common for estimating suspended bed-material and wash loads in rivers over the last decade. Empirical, semi-empirical and physical-based acoustic methods have been applied in different case studies, [...] Read more.

The use of echo-levels from Acoustic Doppler Current Profiler (ADCP) recordings has become more and more common for estimating suspended bed-material and wash loads in rivers over the last decade. Empirical, semi-empirical and physical-based acoustic methods have been applied in different case studies, which provided relationships between scattering particles features derived from samples (i.e., concentration and grain size) and corresponding backscattering strength and sound attenuation. These methods entail different assumptions regarding sediment heterogeneity in the ensonified volume (e.g., particle size distribution (PSD) and spatial concentration gradient). Our work was to compare acoustic backscatter and attenuation properties of suspended sediments, sampled in the rivers Parana and Danube that represented rather different hydro-sedimentological conditions during the surveys. The Parana represents a large sandy river, characterized through a huge watershed and the typical bimodal PSD of sediment in suspension, while the Danube represents in the investigated reach an exposed sand-gravel bed and clay-silt particles transported in the water column in suspension. Sand and clay-silt concentrations clearly dominate the analyzed backscattering strength in the rivers Parana and Danube, respectively, with an effect of PSD level of sorting in the latter case. This comparison clarifies the extent of assumptions made, eventually advising on the actual possibility of applying certain ADCP methods, depending on the expected concentration gradients and PSD of suspended sediment to be investigated. Full article

(This article belongs to the Special Issue Watershed Sediment Process)

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3672 KiB

Open AccessArticle

Integration of a Three-Dimensional Process-Based Hydrological Model into the Object Modeling System

by Giuseppe Formetta, Giovanna Capparelli, Olaf David, Timothy R. Green and Riccardo Rigon

Water 2016, 8(1), 12; https://doi.org/10.3390/w8010012 - 2 Jan 2016

Cited by 6 | Viewed by 8089

Abstract

The integration of a spatial process model into an environmental modeling framework can enhance the model’s capabilities. This paper describes a general methodology for integrating environmental models into the Object Modeling System (OMS) regardless of the model’s complexity, the programming language, and the [...] Read more.

The integration of a spatial process model into an environmental modeling framework can enhance the model’s capabilities. This paper describes a general methodology for integrating environmental models into the Object Modeling System (OMS) regardless of the model’s complexity, the programming language, and the operating system used. We present the integration of the GEOtop model into the OMS version 3.0 and illustrate its application in a small watershed. OMS is an environmental modeling framework that facilitates model development, calibration, evaluation, and maintenance. It provides innovative techniques in software design such as multithreading, implicit parallelism, calibration and sensitivity analysis algorithms, and cloud-services. GEOtop is a physically based, spatially distributed rainfall-runoff model that performs three-dimensional finite volume calculations of water and energy budgets. Executing GEOtop as an OMS model component allows it to: (1) interact directly with the open-source geographical information system (GIS) uDig-JGrass to access geo-processing, visualization, and other modeling components; and (2) use OMS components for automatic calibration, sensitivity analysis, or meteorological data interpolation. A case study of the model in a semi-arid agricultural catchment is presented for illustration and proof-of-concept. Simulated soil water content and soil temperature results are compared with measured data, and model performance is evaluated using goodness-of-fit indices. This study serves as a template for future integration of process models into OMS. Full article

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4426 KiB

Open AccessArticle

Land Use/Cover Change Impacts on Water Table Change over 25 Years in a Desert-Oasis Transition Zone of the Heihe River Basin, China

by Jinfeng Wang, Yanchun Gao and Sheng Wang

Water 2016, 8(1), 11; https://doi.org/10.3390/w8010011 - 29 Dec 2015

Cited by 29 | Viewed by 6409

Abstract

Groundwater resources are becoming the primary factor for maintaining life in arid areas. Understanding land use/cover change and its effect on groundwater depth would enhance land use and groundwater management for typical desert-oasis transition zones. Reduction of groundwater recharge and increase of groundwater [...] Read more.

Groundwater resources are becoming the primary factor for maintaining life in arid areas. Understanding land use/cover change and its effect on groundwater depth would enhance land use and groundwater management for typical desert-oasis transition zones. Reduction of groundwater recharge and increase of groundwater exploitation during 1985 and 2010 led to the decrease of groundwater depth in Linze County. The region with groundwater depth less than 5 m decreased by 187 km² from 1985 to 2010 as a result of industrial growth, agricultural and economic development. Land use has undergone significant spatial and temporal changes. Farmland and built up land expanded by 53.02% and 30.91%, respectively. The expansion of farmland reached a peak between 1996 and 2005 with an increasing rate of 25.70%, while areas of grassland, woodland, water body and unused land decreased, and the decreasing rate was 9.38%, 58.35% and 19.81%. From 1985 to 2010, the groundwater depth rose slightly (0–1.2 m) in the edge of desert (24.21 km²), which was caused by the surrounding farmland irrigation recharge. The drawdown range of groundwater depth between 0 and 3 m was distributed in the central oasis, which was caused by the expansion of farmland and degradation of natural vegetation. This study aims to provide a basis for the reasonable utilization of water resources, the formation of management strategies, as well as to provide ecosystem stability and sustainable development of oases in the study area. Full article

(This article belongs to the Special Issue Hydrologic System Analysis, Patterns, and Predictions for Arid and Semi-arid Environment)

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10696 KiB

Open AccessArticle

Comparison of Four Different Energy Balance Models for Estimating Evapotranspiration in the Midwestern United States

by Ramesh K. Singh and Gabriel B. Senay

Water 2016, 8(1), 9; https://doi.org/10.3390/w8010009 - 26 Dec 2015

Cited by 73 | Viewed by 9995

Abstract

The development of different energy balance models has allowed users to choose a model based on its suitability in a region. We compared four commonly used models—Mapping EvapoTranspiration at high Resolution with Internalized Calibration (METRIC) model, Surface Energy Balance Algorithm for Land (SEBAL) [...] Read more.

The development of different energy balance models has allowed users to choose a model based on its suitability in a region. We compared four commonly used models—Mapping EvapoTranspiration at high Resolution with Internalized Calibration (METRIC) model, Surface Energy Balance Algorithm for Land (SEBAL) model, Surface Energy Balance System (SEBS) model, and the Operational Simplified Surface Energy Balance (SSEBop) model—using Landsat images to estimate evapotranspiration (ET) in the Midwestern United States. Our models validation using three AmeriFlux cropland sites at Mead, Nebraska, showed that all four models captured the spatial and temporal variation of ET reasonably well with an R² of more than 0.81. Both the METRIC and SSEBop models showed a low root mean square error (<0.93 mm·day⁻¹) and a high Nash–Sutcliffe coefficient of efficiency (>0.80), whereas the SEBAL and SEBS models resulted in relatively higher bias for estimating daily ET. The empirical equation of daily average net radiation used in the SEBAL and SEBS models for upscaling instantaneous ET to daily ET resulted in underestimation of daily ET, particularly when the daily average net radiation was more than 100 W·m⁻². Estimated daily ET for both cropland and grassland had some degree of linearity with METRIC, SEBAL, and SEBS, but linearity was stronger for evaporative fraction. Thus, these ET models have strengths and limitations for applications in water resource management. Full article

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2421 KiB

Open AccessArticle

Identifying the Vulnerabilities of Working Coasts Supporting Critical Energy Infrastructure

by David E. Dismukes and Siddhartha Narra

Water 2016, 8(1), 8; https://doi.org/10.3390/w8010008 - 26 Dec 2015

Cited by 9 | Viewed by 5770

Abstract

The U.S. Gulf of Mexico (GOM) is an excellent example of a working coast that supports a considerable degree of critical energy infrastructure across several sectors (crude oil, natural gas, electric power, petrochemicals) and functionalities (production, processing/refining, transmission, distribution). The coastal communities of [...] Read more.

The U.S. Gulf of Mexico (GOM) is an excellent example of a working coast that supports a considerable degree of critical energy infrastructure across several sectors (crude oil, natural gas, electric power, petrochemicals) and functionalities (production, processing/refining, transmission, distribution). The coastal communities of the GOM form a highly productive and complicated human, physical, and natural environment that interacts in ways that are unlike anywhere else around the globe. This paper formulates a Coastal Infrastructure Vulnerability Index (CIVI) that characterizes interactions between energy assets and the physical and human aspects of GOM communities to identify and prioritize, using a multi-dimensional index, coastal vulnerability. The CIVI leads to results that are significantly different than traditional methods and serves as an alternative, and potentially more useful tool for coastal planning and policy, particularly in those areas characterized by very high infrastructure concentrations. Full article

(This article belongs to the Special Issue Resilience and Sustainability of the Mississippi River Delta as a Coupled Natural-Human System)

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1978 KiB

Open AccessArticle

Evaluating Land Subsidence Rates and Their Implications for Land Loss in the Lower Mississippi River Basin

by Lei Zou, Joshua Kent, Nina S.-N. Lam, Heng Cai, Yi Qiang and Kenan Li

Water 2016, 8(1), 10; https://doi.org/10.3390/w8010010 - 26 Dec 2015

Cited by 37 | Viewed by 11111

Abstract

High subsidence rates, along with eustatic sea-level change, sediment accumulation and shoreline erosion have led to widespread land loss and the deterioration of ecosystem health around the Lower Mississippi River Basin (LMRB). A proper evaluation of the spatial pattern of subsidence rates in [...] Read more.

High subsidence rates, along with eustatic sea-level change, sediment accumulation and shoreline erosion have led to widespread land loss and the deterioration of ecosystem health around the Lower Mississippi River Basin (LMRB). A proper evaluation of the spatial pattern of subsidence rates in the LMRB is the key to understanding the mechanisms of the submergence, estimating its potential impacts on land loss and the long-term sustainability of the region. Based on the subsidence rate data derived from benchmark surveys from 1922 to 1995, this paper constructed a subsidence rate surface for the region through the empirical Bayesian kriging (EBK) interpolation method. The results show that the subsidence rates in the region ranged from 1.7 to 29 mm/year, with an average rate of 9.4 mm/year. Subsidence rates increased from north to south as the outcome of both regional geophysical conditions and anthropogenic activities. Four areas of high subsidence rates were found, and they are located in Orleans, Jefferson, Terrebonne and Plaquemines parishes. A projection of future landscape loss using the interpolated subsidence rates reveals that areas below zero elevation in the LMRB will increase from 3.86% in 2004 to 19.79% in 2030 and 30.88% in 2050. This translates to a growing increase of areas that are vulnerable to land loss from 44.3 km²/year to 240.7 km²/year from 2011 to 2050. Under the same scenario, Lafourche, Plaquemines and Terrebonne parishes will experience serious loss of wetlands, whereas Orleans and Jefferson parishes will lose significant developed land, and Lafourche parish will endure severe loss of agriculture land. Full article

(This article belongs to the Special Issue Resilience and Sustainability of the Mississippi River Delta as a Coupled Natural-Human System)

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978 KiB

Open AccessArticle

Identification of Decisive Factors Determining the Continued Use of Rainwater Harvesting Systems for Agriculture Irrigation in Beijing

by Xiao Liang and Meine Pieter Van Dijk

Water 2016, 8(1), 7; https://doi.org/10.3390/w8010007 - 25 Dec 2015

Cited by 14 | Viewed by 6257

Abstract

The success or failure of operating a rainwater harvesting system (RWH) depends on both technological and non-technological factors. The importance of non-technological factors in attaining sustainable RWH operation is rarely emphasized. This study aims to assess the contribution of non-technological factors through determining [...] Read more.

The success or failure of operating a rainwater harvesting system (RWH) depends on both technological and non-technological factors. The importance of non-technological factors in attaining sustainable RWH operation is rarely emphasized. This study aims to assess the contribution of non-technological factors through determining decisive factors involved in the use of RWHs for agriculture irrigation in Beijing. The RWHs for agriculture irrigation in Beijing are not operating as well as expected. If the decisive factors are identified to be non-technological, the significance of non-technological factors will be highlighted. Firstly, 10 impact factors comprising non-technological and technological factors are selected according to both a literature review and interviews with RWH managers. Following this, through an artificial data mining method, rough set analysis, the decisive factors are identified. Results show that two non-technological factors, “doubts about rainwater quality” and “the availability of groundwater” determine whether these systems will continue or cease RWH operation in Beijing. It is, thus, considered necessary to improve public confidence in and motivation on using rainwater for agriculture irrigation, as this is the main obstacle in the sustainable and successful operation of RWHs. Through a case study of RWHs in Beijing, the study verifies the importance of acknowledging non-technological factors to achieve sustainable water management and considers that such factors should receive more attention by decision makers and researchers. Full article

(This article belongs to the Special Issue Rainwater Harvesting: Quantity, Quality, Economics and State Regulations)

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5700 KiB

Open AccessArticle

Multi-Variate Analyses of Flood Loss in Can Tho City, Mekong Delta

by Do Thi Chinh, Animesh K. Gain, Nguyen Viet Dung, Dagmar Haase and Heidi Kreibich

Water 2016, 8(1), 6; https://doi.org/10.3390/w8010006 - 25 Dec 2015

Cited by 38 | Viewed by 8353

Abstract

Floods in the Mekong delta are recurring events and cause substantial losses to the economy. Sea level rise and increasing precipitation during the wet season result in more frequent floods. For effective flood risk management, reliable losses and risk analyses are necessary. However, [...] Read more.

Floods in the Mekong delta are recurring events and cause substantial losses to the economy. Sea level rise and increasing precipitation during the wet season result in more frequent floods. For effective flood risk management, reliable losses and risk analyses are necessary. However, knowledge about damaging processes and robust assessments of flood losses in the Mekong delta are scarce. In order to fill this gap, we identify and quantify the effects of the most important variables determining flood losses in Can Tho city through multi-variate statistical analyses. Our analysis is limited to the losses of residential buildings and contents. Results reveal that under the specific flooding characteristics in the Mekong delta with relatively well-adapted households, long inundation durations and shallow water depths, inundation duration is more important than water depth for the resulting loss. However, also building and content values, floor space of buildings and building quality are important loss-determining variables. Human activities like undertaking precautionary measures also influence flood losses. The results are important for improving flood loss modelling and, consequently, flood risk assessments in the Mekong delta. Full article

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2884 KiB

Open AccessArticle

Effects of Environmental Factors on the Disinfection Performance of a Wastewater Stabilization Pond Operated in a Temperate Climate

by Lei Liu, Geof Hall and Pascale Champagne

Water 2016, 8(1), 5; https://doi.org/10.3390/w8010005 - 25 Dec 2015

Cited by 35 | Viewed by 8991

Abstract

Treatment in a wastewater stabilization pond (WSP) relies on natural purification processes, which can be sensitive to both location and climate. This study investigated the effects of three environmental factors, pH, dissolved oxygen (DO) and temperature, on disinfection efficiency in a WSP system [...] Read more.

Treatment in a wastewater stabilization pond (WSP) relies on natural purification processes, which can be sensitive to both location and climate. This study investigated the effects of three environmental factors, pH, dissolved oxygen (DO) and temperature, on disinfection efficiency in a WSP system consisting of three facultative cells, and operated in a temperate climate region, in Eastern Ontario, Canada. Indicator organism (Escherichia coli (E. coli)) removal in WSP systems is driven by a combination of different factors. Elevated pH and DO concentrations, which are attributed to the presence of algae, are important factors for effective disinfection. Therefore, the presence of algae in natural wastewater treatment systems can contribute appreciably to disinfection. Consequently, based on algal concentrations, removal efficiencies of pathogenic microorganisms during wastewater treatment over the course of a year can be highly variable, where higher removal efficiencies would be expected in summer and fall seasons. Full article

(This article belongs to the Special Issue Microbial Impacts on Water Resources: From Contamination to Remediation)

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4163 KiB

Open AccessArticle

An Integrated Framework for Assessment of Hybrid Water Supply Systems

by Mukta Sapkota, Meenakshi Arora, Hector Malano, Magnus Moglia, Ashok Sharma, Biju George and Francis Pamminger

Water 2016, 8(1), 4; https://doi.org/10.3390/w8010004 - 24 Dec 2015

Cited by 37 | Viewed by 11635

Abstract

Urban water managers around the world are adopting decentralized water supply systems, often in combination with centralized systems. While increasing demand for water arising from population growth is one of the primary reasons for this increased adoption of alternative technologies, factors such as [...] Read more.

Urban water managers around the world are adopting decentralized water supply systems, often in combination with centralized systems. While increasing demand for water arising from population growth is one of the primary reasons for this increased adoption of alternative technologies, factors such as climate change, increased frequency of extreme weather events and rapid urbanization also contribute to an increased rate of adoption of these technologies. This combination of centralized-decentralized water systems approach is referred to as “hybrid water supply systems” and is based on the premise that the provision of alternative water sources at local scales can both extend the capacity of existing centralized water supply infrastructures, and improve resilience to variable climatic conditions. It is important to understand, however, that decentralized water production and reuse may change the flow and composition of wastewater and stormwater, thereby potentially also having negative impacts on its effectiveness and performance. This paper describes a framework to assess the interactions between decentralized water supply systems and existing centralized water servicing approaches using several analytical tools, including water balance modelling, contaminant balance modelling and multi-criteria decision analysis. The framework enables the evaluation of impacts due to change in quantity and quality of wastewater and stormwater on the existing centralized system arising from the implementation of hybrid water supply systems. The framework consists of two parts: (1) Physical system analysis for various potential scenarios and (2) Ranking of Scenarios. This paper includes the demonstration of the first part of the framework for an area of Melbourne, Australia by comparing centralized water supply scenario with a combination of centralized water supply and reuse of treated waste water supply scenario. Full article

(This article belongs to the Special Issue Water Resources Management: Innovation and Challenges in a Changing World)

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