http://www.mdpi.com/journal/water Latest open access articles published in Water at http://www.mdpi.com/journal/water http://www.mdpi.com/2073-4441/5/2/798 Decision support system (DSS) tools are rather popular in the literature on water resources management. The European Project “Splash” conducted a survey of the literature and of DSS implementation in developing countries with specific reference on Africa. Experts in the field were consulted through an ad hoc questionnaire and interviews. The results of the survey indicate that the exchange of experiences amongst projects with similar objectives or even the same case study is very limited, with a tendency towards restarting every time from scratch. As a consequence, it seems that DSS developments have produced only limited positive impacts. Most experts contacted shared either the frustration deriving from the limited impacts on intended end-users, who rarely used the tool after the project end, or in the case of ongoing projects, the preoccupation for future maintenance. Responses from the questionnaires indicate that priority efforts should not focus on developing the tools, but rather on improving the effectiveness and applicability of integrated water resource management legislative and planning frameworks, training and capacity building, networking and cooperation, harmonization of transnational data infrastructures and, very importantly, learning from past experiences and adopting enhanced protocols for DSS development. Water 2013-06-19 5 2 Article 10.3390/w5020798 798 818 2073-4441 2013-06-19 doi: 10.3390/w5020798 Carlo Giupponi Alessandra Sgobbi http://www.mdpi.com/2073-4441/5/2/780 Managing receiving-water quality, ecosystem health and ecosystem service delivery is challenging in regions where extreme rainfall and runoff events occur episodically, confounding and often intensifying land-degradation impacts. We synthesize the approaches used in river, reservoir and coastal water management in the event-driven subtropics of Australia, and the scientific research underpinning them. Land-use change has placed the receiving waters of Moreton Bay, an internationally-significant coastal wetland, at risk of ecological degradation through increased nutrient and sediment loads. The event-driven climate exacerbates this issue, as the waterways and ultimately Moreton Bay receive large inputs of nutrients and sediment during events, well above those received throughout stable climatic periods. Research on the water quality and ecology of the region’s rivers and coastal waters has underpinned the development of a world-renowned monitoring program and, in combination with catchment-source tracing methods and modeling, has revealed the key mechanisms and management strategies by which receiving-water quality, ecosystem health and ecosystem services can be maintained and improved. These approaches provide a useful framework for management of water bodies in other regions driven by episodic events, or where novel stressors are involved (e.g., climate change, urbanization), to support sustained ecosystem service delivery and restoration of aquatic ecosystems. Water 2013-06-19 5 2 Article 10.3390/w5020780 780 797 2073-4441 2013-06-19 doi: 10.3390/w5020780 Catherine Leigh Michele Burford Rod Connolly Jon Olley Emily Saeck Fran Sheldon James Smart Stuart Bunn http://www.mdpi.com/2073-4441/5/2/767 Perchlorate is regarded as an emerging persistent inorganic contaminant. It is widely known that perchlorate is an endocrine disruptor as it competitively inhibits iodide transport in the thyroid gland. As drinking water is the major source of human exposure to perchlorate, its occurrence in commercially available bottled waters purchased in different regions of Italy was investigated. Perchlorate was measured using the rapid, sensitive, and selective LC-ESI-MS/MS (liquid chromatography-electrospray tandem mass spectrometry) method by multiple reaction monitoring (MRM) of the transition 98.8→82.8, which corresponds to the loss of one oxygen atom in the perchlorate ion (ClO4−→ClO3−). The chlorine isotope ratio (35Cl/37Cl) was used as a confirmation tool. The limit of quantification (LOQ) for this method was 5 ng/L, and the recovery ranged from 94% to 108%. Perchlorate was detected in 44 of the 62 drinking waters tested, with concentrations ranging from <5 to 75 ng/L. These values are similar in magnitude to those reported in drinking water from the USA and do not pose an immediate health concern. Water 2013-06-13 5 2 Article 10.3390/w5020767 767 779 2073-4441 2013-06-13 doi: 10.3390/w5020767 Patrizia Iannece Oriana Motta Rossella Tedesco Maurizio Carotenuto Antonio Proto http://www.mdpi.com/2073-4441/5/2/747 Stream metabolism can be used as a measure of freshwater ecosystem health because of its responsiveness to natural and anthropogenic changes. In this study, we used stream metabolic rates to test for the effects of a timber harvest with Louisiana’s current best management practices (BMPs). The study was conducted from 2006 to 2010 in a loblolly pine (Pinus taeda) stand in north-central Louisiana, USA, 45 ha of which was clear cut harvested in the summer of 2007. Dissolved oxygen (DO), water temperature, and stream depth were recorded at a site upstream (serving as a reference) and a site downstream of the harvested area. Using diurnal DO change and an open-system, single-station method at each site, we quantified rates of net ecosystem productivity (NEP), gross primary productivity (GPP), community respiration (CR), and the GPP/CR ratio. The system was predominately heterotrophic, with a GPP/CR ratio of less than one for 82% of the time at the upstream site. No calculated metabolic rate was significantly changed by the timber harvest (two-way ANOVA with interaction; p < 0.001). Overall, the results suggest that timber harvests of similar intensity with Louisiana’s current BMPs may not significantly impact stream biological conditions. Water 2013-06-13 5 2 Article 10.3390/w5020747 747 766 2073-4441 2013-06-13 doi: 10.3390/w5020747 Abram DaSilva Y. Xu George Ice John Beebe Richard Stich http://www.mdpi.com/2073-4441/5/2/728 Forest change and climatic variability are two major drivers for influencing change in watershed hydrology in forest–dominated watersheds. Quantifying their relative contributions is important to fully understand their individual effects. This review paper summarizes the progress on quantifying the relative contributions of forest or land cover change and climatic variability to hydrology in large watersheds using available case studies. It compared pros and cons of various research methods, identified research challenges and proposed future research priorities. Our synthesis shows that the relative hydrological effects of forest changes and climatic variability are largely dependent on their own change magnitudes and watershed characteristics. In some severely disturbed watersheds, impacts of forest changes or land use changes can be as important as those from climatic variability. This paper provides a brief review on eight selected research methods for this type of research. Because each method or technique has its own strengths and weaknesses, combining two or more methods is a more robust approach than using any single method alone. Future research priorities include conducting more case studies, refining research methods, and considering mechanism-based research using landscape ecology and geochemistry approaches. Water 2013-06-13 5 2 Review 10.3390/w5020728 728 746 2073-4441 2013-06-13 doi: 10.3390/w5020728 Xiaohua Wei Wenfei Liu Peicong Zhou http://www.mdpi.com/2073-4441/5/2/698 We show here that a remote sensing (RS) approach is a cost-efficient and accurate method to study water resource dynamics in semi-arid areas. We use a MODIS surface reflectance dataset and a Modified Normalized Difference Water Index (MNDWI) to map the variability of Lake Manyara’s water surface area using a histogram segmentation technique. The results indicate that Lake Manyara’s water surface coverage has been decreasing from 520.25 km2 to 30.5 km2 in 2000 and 2011 respectively. We observe that the lake water surface and the lake water balance displayed a similar pattern from 2006 to 2009, probably initiated by heavy rainfall and low temperature in 2006. Lake water surface area appears to have an inverse relationship with MODIS evapotranspiration (ET) and MODIS land surface temperature (LST). We imply that recent fluctuations of Lake Manyara’s surface water area are a direct consequence of global and regional climate fluctuations. We therefore conclude that, by means of RS it is possible to provide timely and up-to-date water resource information to managers and hence enable optimized and operational decisions for sustainable management and conservation. We suggest that the method employed in this research should be applied to monitor water resource dynamics provided that remotely sensed datasets are available. Water 2013-06-06 5 2 Article 10.3390/w5020698 698 727 2073-4441 2013-06-06 doi: 10.3390/w5020698 Dorothea Deus Richard Gloaguen http://www.mdpi.com/2073-4441/5/2/677 The North China Plain (NCP) is one of the places where the groundwater is most over-exploited in the world. Currently, our understanding on the spatiotemporal variability of the cones of depression in this region is fragmentary. This study intends to simulate the cones of depression in the shallow aquifer across the entire NCP during the whole period from 1960 to 2011. During the simulation, the dominant role of anthropogenic activities is emphasized and carefully taken into account using a Neural Network Algorithm. The results show that cones of depression in the NCP were formed in 1970s and continuously expanded. Their centers were getting deeper with an increasing degree of groundwater exploitation. This simulation provides valuable insights for developing more sustainable groundwater management options after the implementation of the South-to-NorthWater Diversion Project (SNWDP), which is a very important surface water project in China in the near future. The numerical model in this paper is built by MODFLOW, with pumpage data completed by neural network algorithm and hydrogeological parameters calibrated by simulated annealing algorithm. Based on our long-term numerical model for regional groundwater flow in the NCP, one exploitation limitation strategy after the implementation of SNWDP is studied in this paper. The results indicate that the SNWDP is beneficial for groundwater recovery in the NCP. A number of immense groundwater cones will gradually shrink. However, the recovery of the groundwater environment in the NCP will require a long time. Water 2013-06-05 5 2 Article 10.3390/w5020677 677 697 2073-4441 2013-06-05 doi: 10.3390/w5020677 Yuan Zhang Guomin Li http://www.mdpi.com/2073-4441/5/2/659 This review focuses on the ion chromatographic methods for the analyses of natural waters with high ionic strength. At the beginning a natural diversity in ionic composition of waters is highlighted and terminology clarified. In continuation a brief overview of other review articles of potential interest is given. A review of ion chromatographic methods is organized in four sections. The first section comprises articles focused on the determination of ionic composition of water samples as completely as possible. The sections—Selected Anions, Selected Cations and Metals—follow. The most essential experimental conditions used in different methods are summarized in tables for a rapid comparison. Techniques encountered in the reviewed articles comprise: direct determinations of ions in untreated samples with ion- or ion-exclusion chromatography, or electrostatic ion chromatography; matrix elimination with column-switching; pre-concentration with a chelation ion chromatography and purge-and-trap pre-concentration. Different detection methods were used: non-suppressed conductometric or suppressed conductometric, direct spectrometric or spectrometric after a post-column derivetization, and inductively coupled plasma in combination with optical emission or mass spectrometry. Water 2013-06-05 5 2 Review 10.3390/w5020659 659 676 2073-4441 2013-06-05 doi: 10.3390/w5020659 Nataša Gros http://www.mdpi.com/2073-4441/5/2/643 This article examines some of the forms of water management in Shanxi [山西] and Shaanxi [陕西] provinces during the Ming and Qing dynasties. Facing serious water shortages and shrinking state power for water management, the local society in Shanxi and Shaanxi took over water management and gradually formed a local self-government system for the water resources. Depending on water management organizations in which the local gentry were the core power, the water rules were based on natural topographic conditions, historical water practices in the locality, traditional moral-ethical ideas, and even water policies and water laws. This water management system played a positive role in mobilizing the participation of members, preventing opportunistic behavior such as free riding and rent seeking, while decreasing the probability of water conflicts and the costs of litigation. However, this water management system was also subject to endemic corruption because of the lack of effective monitoring from the local government. As similar problems appear to exist in China today, this article analyzes the features of this water management system, and examines the problems that faced those systems so as to provide a warning from history for modern society. Water 2013-06-04 5 2 Article 10.3390/w5020643 643 658 2073-4441 2013-06-04 doi: 10.3390/w5020643 Xiaohong Dang Michael Webber Dan Chen Mark Wang http://www.mdpi.com/2073-4441/5/2/640 The following paragraphs are reproduced from the website of the publisher [1]. Water is becoming one of the world’s most crucial concerns. A third of the world’s population has severe water shortage, while three quarters of the global population lives in deltas which run the risk of severe flooding. In addition, many more face problems of poor water quality. Water 2013-06-03 5 2 New Book Received 10.3390/w5020640 640 642 2073-4441 2013-06-03 doi: 10.3390/w5020640 Shu-Kun Lin http://www.mdpi.com/2073-4441/5/2/638 The following paragraphs are reproduced from the website of the publisher [1]. Professor Pollack takes us on a fantastic voyage through water, showing us a hidden universe teeming with physical activity that provides answers so simple that any curious person can understand. In conversational prose, Pollack lays a simple foundation for understanding how changes in water’s structure underlie most energetic transitions of form and motion on earth. Water 2013-06-03 5 2 New Book Received 10.3390/w5020638 638 639 2073-4441 2013-06-03 doi: 10.3390/w5020638 Shu-Kun Lin http://www.mdpi.com/2073-4441/5/2/629 As part of measures being taken against global warming, the reduction of CO2 emissions by retrofitting for water-saving fittings in homes is spreading throughout the world. However, although this retrofitting reduces the environmental impact at the use stage, it generates new impacts at the production and disposal stages. In addition, there has been little research that discusses the reduction in environmental impact obtained by retrofitting from the viewpoint of the overall life cycle of such fittings. In this paper, an evaluation of the environmental impact of retrofitting in terms of the entire life cycle was carried out for toilet bowls and showerheads. The findings show that even for a toilet bowl that generates a large environmental load at the production stage, there is no overall increase in the environmental impact by retrofitting for the average usable life of 20 years. Water 2013-05-31 5 2 Article 10.3390/w5020629 629 637 2073-4441 2013-05-31 doi: 10.3390/w5020629 Yasutoshi Shimizu http://www.mdpi.com/2073-4441/5/2/617 Aquifers recharge mainly by local rainfall, which depend on the air mass humidity and orographic lifting, causing rain. The stable isotopes of the water molecule, i.e., oxygen-18 and deuterium, are useful tracers to determine the water source origin. Moreover, the calculation of the deuterium excess enables one to differentiate between the air masses from the Atlantic Ocean or the Mediterranean Sea. A transect from one coast to the other one and going through the city of Toulouse have been made to sample the groundwater and determine their isotopic characteristic. A monthly rainfall sampling has also been done over one year, close to the city Toulouse, to see how the d-excess values range over the season. The discussion replaces these results in available isotopic data. Water 2013-05-17 5 2 Article 10.3390/w5020617 617 628 2073-4441 2013-05-17 doi: 10.3390/w5020617 Luc Lambs Issam Moussa Frederic Brunet http://www.mdpi.com/2073-4441/5/2/593 Urbanized delta areas worldwide share a growing tendency of exposure to water stress induced by the effects of climate change and anthropogenic factors, threatening the operation of infrastructure systems and future urban development. The important synergistic impacts coexisting with freshwater scarcity are increasing urbanization rates, subsiding soils, saltwater intrusion in aquifers and rivers, coastal erosion, and increased flooding. Innovative design strategies and concepts for the integration of decentralized rainwater management measures can contribute to the integrated and climate resilient planning of urban spaces that are threatened by climate change scenarios that worsen the security of urban infrastructures and the future availability of fresh water. Decentralized rainwater management, including retention, storage, and reuse strategies that are integrated into spatial planning and urban design, can reduce flood risks while simultaneously enhancing freshwater availability. This paper discusses a paradigm shift in urban water management, from centralized to decentralized management (that is, from threats to opportunities), using the example of two case studies. Concepts and strategies for building climate resilient cities, which address flood control, the protection of freshwater resources, and the harmonization of a natural and more sustainable water balance, are presented for Almere (Rhine Schelde Delta, The Netherlands) and Hsingchu (Dotzpu Delta, Taiwan). Water 2013-05-10 5 2 Article 10.3390/w5020593 593 616 2073-4441 2013-05-10 doi: 10.3390/w5020593 Thorsten Schuetze Lorenzo Chelleri http://www.mdpi.com/2073-4441/5/2/578 Irrigation practice for rice culture can be especially challenging in areas with limited water supply and soil salinization. In this study, we carried out a field experiment to assess the effects of different water discharge frequencies on soil salt content, rice yield and water use efficiency on a saline-sodic soil in a semi-arid region of Northeast China. The experiment comprised of three frequency levels of discharge [9-time (I-9-30), 6-time (I-6-30) and 3-time (I-3-30) discharge, all followed with a 30-mm irrigation] in comparison with the traditional irrigation practice of 2-time discharge followed with an 80-mm irrigation (I-2-80). Our initial hypothesis was that increasing discharge frequency would increase both salt reduction and rice yield. Daily precipitation was recorded by a nearby weather station, and evapotranspiration and soil water percolation rates were measured at experimental sites using soil pits. The measurements were used to establish a water balance for each treatment. Our results showed that soil salt reduction increased with the increasing discharge frequency at a 30-mm irrigation water depth. The 9-time discharge reduced a large amount of soil salt (995.0 kg ha−1) after five months of the study. Rice yield also increased with the increasing discharge frequency with a 30-mm irrigation water depth; however, when compared to the traditional 2-time discharge followed with an 80-mm irrigation, rice yield at the sites with more frequent discharge (i.e., I-9-30, I-6-30 and I-3-30) was 11%–18% lower. Because of this, rice yield and irrigation water use efficiency were significantly higher under the traditional practice of high-irrigation with low-frequency discharge (I-2-80) than under I-9-30, I-6-30 and I-3-30. These results indicate a need for a trade-off amongst salt reduction, rice yield and water use when considering selection of irrigation and discharge schedules. Water 2013-05-07 5 2 Article 10.3390/w5020578 578 592 2073-4441 2013-05-07 doi: 10.3390/w5020578 Yueqing Chen Guangxin Zhang Y. Xu Zhigang Huang http://www.mdpi.com/2073-4441/5/2/560 The dam-break induced loads and their effects on buildings are of vital importance for assessing the vulnerability of buildings in flood-prone areas. A comprehensive methodology, for risk assessment of buildings subject to flooding, is nevertheless still missing. This research aims to take a step forward by following previous research. To this aim, (1) five statistical procedures including: simple correlation analysis, multiple linear regression model, stepwise multiple linear regression model, principal component analysis and cluster analysis are used to study relationship between mean normalized force on structure and other related variables; (2) a new and efficient variable that can take into account both the shape of the structure and flow conditions is proposed; (3) a new and practical formula for predicting the mean normalized force is suggested for different types of obstacles, which is missing in the previous research. Water 2013-05-06 5 2 Article 10.3390/w5020560 560 577 2073-4441 2013-05-06 doi: 10.3390/w5020560 Jasna Duricic Tarkan Erdik Ali Pektaş Petrus van Gelder http://www.mdpi.com/2073-4441/5/2/540 Many streams in the US are impaired because of high Soluble Reactive Phosphorous (SRP) contributions from agriculture. However, the drivers of ecological processes that lead to SRP loss in baseflow from groundwater are not sufficiently understood to design effective Best Management Practices (BMPs). In this paper, we examine how soil temperature and water table depth influence the SRP concentrations in groundwater for a dairy farm in a valley bottom in the Catskills (NY, USA). Measured SRP concentrations in groundwater and baseflow were greater during the fall, when soil temperatures are warmer, than during winter and spring. The observed concentrations were within the bounds predicted by groundwater temperatures using the Arrhenius equation, except during fall, when concentrations rose above these predictions. These elevated concentrations were likely caused by mineralization and consequent accumulation of phosphorous (P) in summer. In addition, SRP concentrations were greater in near-stream areas, where water tables where higher. In short, SRP concentrations are dependent on temperature, demonstrating the importance of understanding the underlying mechanism of ecological processes. In addition, results suggest BMPs that apply manure on land having a deep groundwater, instead of on land with a shallow water table will lower overall SRP contributions. Water 2013-05-02 5 2 Article 10.3390/w5020540 540 559 2073-4441 2013-05-02 doi: 10.3390/w5020540 Francisco Flores-López Zachary Easton Larry Geohring Peter Vermeulen Van Haden Tammo Steenhuis http://www.mdpi.com/2073-4441/5/2/525 Chlorophyll-a (Chl-a) concentration is considered as a key indicator of the eutrophic status of inland water bodies. Various algorithms have been developed for estimating Chl-a in order to improve the accuracy of predictive models. The objective of this study is to assess the potential of hyperspectral multi-band indices to estimate the Chl-a concentration in Dianshan Lake, which is the largest lake in Shanghai, an international metropolis of China. Based on field spectral measurements and in-situ Chl-a concentration collected on 7–8 September 2010, hyperspectral multi-band indices were calibrated to estimate the Chl-a concentration with optimal wavelengths selected by model tuning. A three-band index accounts for 87.36% (R2 = 0.8736) of the Chl-a variation. A four-band index, which adds a wavelength in the near infrared (NIR) region, results in a higher R2 (0.8997) by removing the absorption and backscattering effects of suspended solids. To test the applicability of the proposed indices for routinely monitoring of Chl-a in inland lakes, simulated Hyperion and real HJ-1A satellite data were selected to estimate the Chl-a concentration. The results show that the explanatory powers of these satellite hyperspectral multi-band indices are relatively high with R2 = 0.8559, 0.8945, 0.7969, and 0.8241 for simulated Hyperion and real HJ-1A satellite data, respectively. All of the results provide strong evidence that hyperspectral multi-band indices are promising and applicable to estimate Chl-a in eutrophic inland lakes. Water 2013-04-29 5 2 Article 10.3390/w5020525 525 539 2073-4441 2013-04-29 doi: 10.3390/w5020525 Liguo Zhou Bo Xu Weichun Ma Bin Zhao Linna Li Hongyan Huai http://www.mdpi.com/2073-4441/5/2/505 Soil-based wastewater treatment systems, or leachfields, rely on microbial processes for improving the quality of wastewater before it reaches the groundwater. These processes are affected by physicochemical system properties, such as O2 availability, and disturbances, such as the presence of antimicrobial compounds in wastewater. We examined the microbial community structure of leachfield mesocosms containing native soil and receiving domestic wastewater under intermittently-aerated (AIR) and unaerated (LEACH) conditions before and after dosing with tetracycline (TET). Community structure was assessed using phospholipid fatty acid analysis (PLFA), analysis of dominant phylotypes using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR–DGGE), and cloning and sequencing of 16S rRNA genes. Prior to dosing, the same PLFA biomarkers were found in soil from AIR and LEACH treatments, although AIR soil had a larger active microbial population and higher concentrations for nine of 32 PLFA markers found. AIR soil also had a larger number of dominant phylotypes, most of them unique to this treatment. Dosing of mesocosms with TET had a more marked effect on AIR than LEACH soil, reducing the size of the microbial population and the number and concentration of PLFA markers. Dominant phylotypes decreased by ~15% in response to TET in both treatments, although the AIR treatment retained a higher number of phylotypes than the LEACH treatment. Fewer than 10% of clones were common to both OPEN ACCESS Water 2013, 5 506 AIR and LEACH soil, and fewer than 25% of the clones from either treatment were homologous with isolates of known genus and species. These included human pathogens, as well as bacteria involved in biogeochemical transformations of C, N, S and metals, and biodegradation of various organic contaminants. Our results show that intermittent aeration has a marked effect on the size and structure of the microbial community that develops in a native leachfield soil. In addition, there is a differential response of the microbial communities of AIR and LEACH soil to tetracycline addition which may be linked to changes in function. Water 2013-04-25 5 2 Article 10.3390/w5020505 505 524 2073-4441 2013-04-25 doi: 10.3390/w5020505 Janet Atoyan Andrew Staroscik David Nelson Erika Patenaude David Potts José Amador http://www.mdpi.com/2073-4441/5/2/480 Stable and radioactive tracers were utilized in concert to characterize geochemical processes in a complex coastal groundwater system and to provide constraints on the kinetics of rock/water interactions. Groundwater samples from wells within the Dominguez Gap region of Los Angeles County, California were analyzed for a suite of major cations (Na+, K+, Mg2+, Ca2+) and anions (Cl−, SO42−), silica, alkalinity, select trace elements (Ba, B, Sr), dissolved oxygen, stable isotopes of hydrogen (δD), oxygen (δ18O), dissolved inorganic carbon (δ13CDIC), and radioactive isotopes (3H, 222Rn and 223,224,226,228Ra). In the study area, groundwater may consist of a complex mixture of native groundwater, intruded seawater, non-native injected water, and oil-field brine water. In some wells, Cl− concentrations attained seawater-like values and in conjunction with isotopically heavier δ18O values, these tracers provide information on the extent of seawater intrusion and/or mixing with oil-field brines. Groundwater 3H above 1 tritium unit (TU) was observed only in a few select wells close to the Dominguez Gap area and most other well groundwater was aged pre-1952. Based on an initial 14C value for the study site of 90 percent modern carbon (pmc), groundwater age estimates likely extend beyond 20 kyr before present and confirm deep circulation of some native groundwater through multiple aquifers. Enriched values of groundwater δ13CDIC in the absence of SO42− imply enhanced anaerobic microbial methanogenesis. While secular equilibrium was observed for 234U/238U (activity ratios ~1) in host matrices, strong isotopic fractionation in these groundwater samples can be used to obtain information of adsorption/desorption kinetics. Calculated Ra residence times are short, and the associated desorption rate constant is about three orders of magnitude slower than that of the adsorption rate constant. Combined stable- and radio-isotopic results provide unique insights into aquifer characteristics, such as geochemical cycling, rock/water interactions, and subsurface transport and mixing. Water 2013-04-19 5 2 Article 10.3390/w5020480 480 504 2073-4441 2013-04-19 doi: 10.3390/w5020480 Peter Swarzenski Mark Baskaran Robert Rosenbauer Brian Edwards Michael Land http://www.mdpi.com/2073-4441/5/2/462 Sustainable drainage systems (SuDS; or best management practices) are increasingly being used as ecological engineering techniques to prevent the contamination of receiving watercourses and groundwater. Permeable paving is a SuDS technique, which is commonplace in car parks, driveways and minor roads where one of their functions is to improve the quality of urban runoff. However, little is known about the water quality benefits of incorporating an upper geotextile within the paving structure. The review focuses on five different categories of pollutants: organic matter, nutrients, heavy metals, motor oils, suspended solids originating from street dust, and chloride. The paper critically assesses results from previous international tests and draws conclusions on the scientific rigour and significance of the data. Findings indicate that only very few studies have been undertaken to address the role of geotextiles directly. All indications are that the presence of a geotextile leads only to minor water quality improvements. For example, suspended solids are being held back by the geotextile and these solids sometimes contain organic matter, nutrients and heavy metals. However, most studies were inconclusive and data were often unsuitable for further statistical analysis. Further long-term research on industry-relevant, and statistically and scientifically sound, experimental set-ups is recommended. Water 2013-04-18 5 2 Review 10.3390/w5020462 462 479 2073-4441 2013-04-18 doi: 10.3390/w5020462 Miklas Scholz http://www.mdpi.com/2073-4441/5/2/443 The mountain pine beetle epidemic in British Columbia has covered 18.1 million hectares of forest land showing the potential for exceptionally large-scale disturbance to influence watershed hydrology. Pine stands killed by the epidemic can experience reduced levels of evapotranspiration and precipitation interception, which can translate into an increase in soil moisture as observed by some forest practitioners during salvage logging in the epicenter of the outbreak. They reported the replacement of summer ground, dry firm soil areas, with winter ground areas identified by having wetter, less firm soils upon which forestry equipment operation is difficult or impossible before winter freeze-up. To decrease the likelihood of soil disturbance from harvesting, a set of hazard indicators was developed to predict wet ground areas in areas heavily infested by the mountain pine beetle. Hazard indicators were based on available GIS data, aerial photographs, and local knowledge. Indicators were selected by an iterative process that began with office-based selection of potential indicators, model development and prediction, field verification, and model refinement to select those indicators that explained most field data variability. Findings indicate that the most effective indicators were lodgepole pine content, understory, drainage density, soil texture, and the topographic index. Water 2013-04-15 5 2 Article 10.3390/w5020443 443 461 2073-4441 2013-04-15 doi: 10.3390/w5020443 John Rex Stéphane Dubé Vanessa Foord http://www.mdpi.com/2073-4441/5/2/420 Dissolved oxygen concentration is a key parameter for characterizing natural and wastewaters and for assessing the global state of the environment in general. The decrease of dissolved oxygen levels in the world’s oceans, which is becoming increasingly obvious, is expected to have an impact on the whole ecosystem of the Earth, including the carbon cycle, the climate, etc. Dissolved oxygen measurements by sensors are often deemed easy measurements by routine laboratories. In reality, the physical and chemical processes underlying the measurements are complex and these measurements are not at all as robust as often considered. Recently an international in situ interlaboratory comparison measurement of dissolved oxygen concentration took place at the University of Tartu. The results revealed that the routine laboratories as a rule still do not fully master the art of dissolved oxygen concentration measurement: Out of altogether 63 measurement results obtained by the participants 52% were unacceptable according to the En numbers. Based on the analysis of the results of the intercomparison a set of tools and recommendations are given to the participants of how to improve the quality of their results. Water 2013-04-12 5 2 Article 10.3390/w5020420 420 442 2073-4441 2013-04-12 doi: 10.3390/w5020420 Teemu Näykki Lauri Jalukse Irja Helm Ivo Leito http://www.mdpi.com/2073-4441/5/2/405 The role of plants in the treatment of effluents by constructed wetland (CW) systems is under debate. Here, we review ways in which plants can affect CW processes and suggest two novel functions for plants in CWs. The first is salt phytoremediation by halophytes. We have strong evidence that halophytic plants can reduce wastewater salinity by accumulating salts in their tissues. Our studies have shown that Bassia indica, a halophytic annual, is capable of salt phytoremediation, accumulating sodium to up to 10% of its dry weight. The second novel use of plants in CWs is as phytoindicators of water quality. We demonstrate that accumulation of H2O2, a marker for plant stress, is reduced in the in successive treatment stages, where water quality is improved. It is recommended that monitoring and management of CWs consider the potential of plants as phytoremediators and phytoindicators. Water 2013-04-08 5 2 Review 10.3390/w5020405 405 419 2073-4441 2013-04-08 doi: 10.3390/w5020405 Oren Shelef Amit Gross Shimon Rachmilevitch http://www.mdpi.com/2073-4441/5/2/394 From the standpoint of the preservation of water resources, rainwater and reclaimed water have been widely used in buildings in many countries. However, the CO2 emission factors of these two waters—factors that determine their environmental impacts—have not been calculated. In a previous study, the CO2 emission factor of water for waterworks and sewer systems was determined. In this paper, we evaluate the emission factors of rainwater and reclaimed water in the same manner. First, the emission factor for pumping water in buildings is determined using published values for operating performances. About half of the residential dwellings in Japan are multistory apartments, and these apartments use pumps for the delivery of water. The emission factor of pumping is calculated as 0.69 kg CO2/m3, which adds 16% to the emission factor of waterworks and sewer systems. Next, the CO2 emission factors of rainwater and reclaimed water are calculated for different water delivery cases in buildings. As a result, it is found that the use of reclaimed water increases CO2 emissions by 62%, compared to the use of ordinary water. Water 2013-04-08 5 2 Article 10.3390/w5020394 394 404 2073-4441 2013-04-08 doi: 10.3390/w5020394 Yasutoshi Shimizu Satoshi Dejima Kanako Toyosada http://www.mdpi.com/2073-4441/5/2/379 Floodplains and river corridor wetlands may be effectively managed for reducing nutrients and carbon. However, our understanding is limited to the reduction potential of these natural riverine systems. This study utilized the long-term (1978–2004) river discharge and water quality records from an upriver and a downriver location of the Atchafalaya River to quantify the inflow, outflow, and inflow–outflow mass balance of total Kjeldahl nitrogen (TKN = organic nitrogen + ammonia nitrogen), nitrate + nitrite nitrogen (NO3 + NO2), total phosphorous (TP), and total organic carbon (TOC) through the largest river swamp basin in North America. The study found that, over the past 27 years, the Atchafalaya River Basin (ARB) acted as a significant sink for TKN (annual retention: 24%), TP (41%), and TOC (12%), but a source for NO3 + NO2 nitrogen (6%). On an annual basis, ARB retained 48,500 t TKN, 16,900 t TP, and 167,100 t TOC from the river water. The retention rates were closely and positively related to the river discharge with highs during the winter and spring and lows in the late summer. The higher NO3 + NO2 mass outflow occurred throughout spring and summer, indicating an active role of biological processes on nitrogen as water and air temperatures in the basin rise. Water 2013-04-03 5 2 Article 10.3390/w5020379 379 393 2073-4441 2013-04-03 doi: 10.3390/w5020379 Y. Xu http://www.mdpi.com/2073-4441/5/2/356 The paper discusses the potential of action research to meet the challenges entailed in institutional design for urban water management. Our overall aim is to briefly present action research and discuss its methodological merits with regard to the challenges posed by the different conceptual bases for extrapolating the effects of institutional design on institutional change. Thus, our aim is to explore how Action Research meets the challenge of scoping the field in an open fashion for determining the appropriate mechanisms of institutional change and supporting the emerging of new water institutions. To accomplish this aim, we select the Water Framework Directive (WFD) as an illustrative driving force requiring changes in water management practices and implying the need for the emergence of new institutions. We employ a case of urban water management in the Volos Metropolitan Area, part of the Thessaly region in Greece, where a Pilot River Basin Plan was implemented. By applying action research and being involved in a long process of interaction between stakeholders, we examine the emergence of new institutions dealing with urban water management under the general principles of the major driving force for change: the WFD. Water 2013-04-03 5 2 Article 10.3390/w5020356 356 378 2073-4441 2013-04-03 doi: 10.3390/w5020356 Dimitrios Zikos Andreas Thiel http://www.mdpi.com/2073-4441/5/2/342 In this paper, a new ferric chloride-(polyvinylpyrrolidone-grafted-polyacrylamide) hybrid copolymer was successfully synthesized by free radical polymerization in solution using ceric ammonium nitrate as redox initiator. The hybrid copolymer was characterized by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). Response surface methodology (RSM), involving central composite design (CCD) matrix with two of the most important operating variables in the flocculation process; hybrid copolymer dosage and pH were utilized for the study and for the optimization of the wastewater treatment process. Response surface analyses showed that the experimental data could be adequately fitted to quadratic polynomial models. Under the optimum conditions, the turbidity and chemical oxygen demand (COD) removal efficiencies were 96.4% and 83.5% according to RSM optimization, whereas the optimum removals based on the genetic algorithm (GA) were 96.56% and 83.54% for the turbidity and COD removal models. Based on these results, wastewater treatment using this novel hybrid copolymer has proved to be an effective alternative in the overseeing of turbidity and COD problems of municipal wastewater. Water 2013-03-26 5 2 Article 10.3390/w5020342 342 355 2073-4441 2013-03-26 doi: 10.3390/w5020342 Ammar Dawood Yilian Li http://www.mdpi.com/2073-4441/5/2/327 The pronounced increase in the cycling and deposition of biologically reactive dissolved inorganic nitrogen (DIN) over large areas globally not only cause increased concentrations of DIN in surface waters, but it will also affect nutrient ratios in rivers, lakes and coastal areas. This review addresses the flux and fate of DIN, focusing NO3 in lakes of boreal and alpine catchments. Not only DIN-deposition, but also catchment properties strongly affect the concentrations of NO3 in lakes, as well as NO3:total P (TP) ratios. This ratio displays an extreme variability, and does also serve as an indicator of shift between N and P-limitation of aquatic autotrophs. A high share of forests and bogs in the catchment generally decreases NO3:total P ratios, while alpine and subalpine catchments with sparse vegetation cover may have high NO3:total P ratios, especially in regions with high DIN-deposition. Several empirical and experimental studies indicate a shift from an initial N to P-limitation, but for N-limited lakes, an increased growth of phytoplankton, periphytes and macrophytes may be accredited to elevated inputs of DIN. An intensified P-limitation may also be a consequence of elevated DIN-deposition. This P-limitation may again yield higher C:P-ratios in autotrophs with negative impacts on grazers and higher trophic levels. Water 2013-03-25 5 2 Review 10.3390/w5020327 327 341 2073-4441 2013-03-25 doi: 10.3390/w5020327 Dag Hessen http://www.mdpi.com/2073-4441/5/1/312 The practice of rainwater harvesting (RWH) is spreading rapidly in urban areas. This article studies the impact of a possible generalization of this practice for municipalities by proposing a new method to quantify the potential for potable water savings (PPWS) by using rainwater harvesting at the urban level. The proposed method is based on the adaptation of an already validated model assessing the PPWS for single buildings and the use of urban databases. Two concepts are introduced: (1) the “building type” that allows gathering all the buildings sharing common features; and (2) the “equivalent building,” which is used to assess the PPWS of a set of buildings (of a same building type) as if it were a single building. In the case of the municipality of Colombes (located in the suburbs of Paris), the method shows that the PPWS by using rainwater harvesting represents about 10% of the total potable water consumption: the residential buildings account for 64% of this potential. This method can be applied to other municipalities with a level of acceptable reliability with regard to the means to be implemented in terms of collecting information. Water 2013-03-18 5 1 Article 10.3390/w5010312 312 326 2073-4441 2013-03-18 doi: 10.3390/w5010312 Ali Belmeziti Olivier Coutard Bernard de Gouvello http://www.mdpi.com/2073-4441/5/1/292 This review article compiles the various advances made since 2008 in sustainable high-rate anaerobic technologies with emphasis on their performance enhancement when treating agro-food industrial wastewater. The review explores the generation and characteristics of different agro-food industrial wastewaters; the need for and the performance of high rate anaerobic reactors, such as an upflow anaerobic fixed bed reactor, an upflow anaerobic sludge blanket (UASB) reactor, hybrid systems etc.; operational challenges, mass transfer considerations, energy production estimation, toxicity, modeling, technology assessment and recommendations for successful operation Water 2013-03-15 5 1 Review 10.3390/w5010292 292 311 2073-4441 2013-03-15 doi: 10.3390/w5010292 Rajinikanth Rajagopal Noori Saady Michel Torrijos Joseph Thanikal Yung-Tse Hung http://www.mdpi.com/2073-4441/5/1/280 Nonpoint source pollution control and stormwater management are two objectives in managing mixed land use watersheds like those in New Jersey. Various best management practices (BMPs) have been developed and implemented to achieve both objectives. This study assesses the cost-effectiveness of selected BMPs for agricultural nonpoint source pollution control and stormwater management in the Neshanic River watershed, a typical mixed land use watershed in central New Jersey, USA. The selected BMPs for nonpoint source pollution control include cover crops, prescribed grazing, livestock access control, contour farming, nutrient management, and conservation buffers. The selected BMPs for stormwater management are rain gardens, roadside ditch retrofitting, and detention basin retrofitting. Cost-effectiveness is measured by the reduction in pollutant loads in total suspended solids and total phosphorus relative to the total costs of implementing the selected BMPs. The pollution load reductions for these BMPs are based on the total pollutant loads in the watershed simulated by the Soil and Water Assessment Tool and achievable pollutant reduction rates. The total implementation cost includes BMP installation and maintenance costs. The assessment results indicate that the BMPs for the nonpoint source pollution control are generally much more cost-effective in improving water quality than the BMPs for stormwater management. Water 2013-03-13 5 1 Article 10.3390/w5010280 280 291 2073-4441 2013-03-13 doi: 10.3390/w5010280 Zeyuan Qiu http://www.mdpi.com/2073-4441/5/1/262 P index is a management tool commonly used to identify critical source areas (CSAs) in agro-catchments. We tested the applicability of several P-index models adjusted to Eastern Mediterranean conditions. On the basis of model structure and data requirements, we selected the Arkansas model and two models with the RUSLE equation and runoff curve number (RCN). Concurrently, we developed a GIS-based Hermon-P model which was designed to simulate rainfall–runoff events representing the major nutrient-transport mechanism in Eastern Mediterranean. The P index values computed by the Arkansas and RUSLE models exhibited low correlation (r2 < 0.32) with the measured soluble reactive (SRP) and total P (TP), while the RCN model result correlations were somewhat higher (r2 = 0.53 for SRP and 0.45 for TP). High correlations between the calculated and measured P during rainfall–runoff events were only achieved with the Hermon model (r2 = 0.77 to 0.9). These high coefficients resulted from avoiding subjective categorization of the continuous variables and using the measured site-specific erosional predictors instead. On one occasion, during the first significant runoff event of the year, the Hermon model failed to predict total P in the stream water (r2 = 0.14) because of considerable resuspension of stream sediments. Most of the P-index models are based on the perceptual transfer-continuum framework that was developed for temperate agro-catchments; this framework does not consider P resuspension along streams during rainfall–runoff events. Hence, a new set of equations should be added to the P index to account for potential resuspension in Eastern Mediterranean streams at the beginning of the hydrological year. Water 2013-03-12 5 1 Article 10.3390/w5010262 262 279 2073-4441 2013-03-12 doi: 10.3390/w5010262 Oren Reichmann Yona Chen Litaor Iggy http://www.mdpi.com/2073-4441/5/1/243 This study assesses the water quality of the Upper Santa Cruz Watershed in southern Arizona in terms of fecal coliform and Escherichia coli (E. coli) bacteria concentrations discharged as treated effluent and from nonpoint sources into the Santa Cruz River and surrounding tributaries. The objectives were to (1) assess the water quality in the Upper Santa Cruz Watershed in terms of fecal coliform and E. coli by comparing the available data to the water quality criteria established by Arizona, (2) to provide insights into fecal indicator bacteria (FIB) response to the hydrology of the watershed and (3) to identify if point sources or nonpoint sources are the major contributors of FIB in the stream. Assessment of the available wastewater treatment plant treated effluent data and in-stream sampling data indicate that water quality criteria for E. coli and fecal coliform in recreational waters are exceeded at all locations of the Santa Cruz River. For the wastewater discharge, 13%–15% of sample concentrations exceeded the 800 colony forming units (cfu) per 100 mL sample maximum for fecal coliform and 29% of samples exceeded the full body contact standard of 235 cfu/100 mL established for E. coli; while for the in-stream grab samples, 16%–34% of sample concentrations exceeded the 800 cfu/100 mL sample maximum for fecal coliforms and 34%–75% of samples exceeded the full body contact standard of 235 cfu/100 mL established for E. coli. Elevated fecal coliform and E. coli concentrations were positively correlated with periods of increased streamflow from rainfall. FIB concentrations observed in-stream are significantly greater (p-value < 0.0002) than wastewater treatment plants effluent concentrations; therefore, water quality managers should focus on nonpoint sources to reduce overall fecal indicator loads. Findings indicate that fecal coliform and E. coli concentrations are highly variable, especially along urban streams and generally increase with streamflow and precipitation events. Occurrences of peaks in FIB concentrations during baseflow conditions indicate that further assessment of ecological factors such as interaction with sediment, regrowth, and source tracking are important to watershed management. Water 2013-03-11 5 1 Article 10.3390/w5010243 243 261 2073-4441 2013-03-11 doi: 10.3390/w5010243 Emily Sanders Yongping Yuan Ann Pitchford http://www.mdpi.com/2073-4441/5/1/239 Sustainable water systems often comprise complex combinations of traditional and new system components that mimic natural processes. These green systems aim to protect public health and safety, and restore natural and human landscapes. Green infrastructure elements such as most sustainable drainage systems trap storm water but may contaminate groundwater. There is a need to summarize recent trends in sustainable water systems management in a focused document. The aim of this special issue is therefore to disseminate and share scientific findings on novel sustainable water systems addressing recent problems and opportunities. This special issue focuses on the following key topics: climate change adaptation and vulnerability assessment of water resources systems; holistic water management; carbon credits; potable water savings; sustainable water technologies; nutrient management; holistic storm water reuse; water and wastewater infrastructure planning; ecological status of watercourses defined by the Water Framework Directive. The combined knowledge output advances the understanding of sustainable water, wastewater and storm water systems in the developed and developing world. The research highlights the need for integrated decision-support frameworks addressing the impact of climate change on local and national water resources management strategies involving all relevant stakeholders at all levels. Water 2013-02-06 5 1 Editorial 10.3390/w5010239 239 242 2073-4441 2013-02-06 doi: 10.3390/w5010239 Miklas Scholz http://www.mdpi.com/2073-4441/5/1/224 In recent years, the Taiwan government has established a number of flood control facilities such as dikes, pumping stations and drainage systems to effectively reduce downstream flooding. However, with continued development and urbanization of catchment areas, the original designs of most flood control facilities have become outdated. Hillside lands in the upper and middle reaches of river basins have undergone urban development through unsound engineering practices, paving the way for heavy downstream flooding. Therefore, proper river basin management should include both upstream and downstream sides. The main purpose of the paper is to simulate non-urban inundation areas with various degrees of development (0%, 10%, 20%, 40% and 60%), over two different return periods of 25 years and 200 years, for intensive rainfall events in the Shi-Chi District, Taiwan. Through hydrological analysis and numerical simulations of inundation, quantitative data on inundation potential have been established based on the land development conditions along the hillsides on the upper and middle reaches of the Keelung River Basin. The simulated results show that the increase in the extent of land development in the upper reaches causes an increase in the area and depth of inundation, resulting in an increased risk of flooding in downstream areas. If the land-use policy makers in the upper reaches of the river basin’s hillsides do not properly manage the land development, the risk of flooding in downstream areas will increase. In such an event, the policy makers should first review the situation to understand the problem with the consideration of this study. Thus, proper development and flood mitigation in hillsides can be established. Water 2013-02-06 5 1 Article 10.3390/w5010224 224 238 2073-4441 2013-02-06 doi: 10.3390/w5010224 Wei-Hsien Teng Chih-Hung Chen http://www.mdpi.com/2073-4441/5/1/197 This paper examines the perceptions of urban and regional water consumers in three areas of South Australia on the fairness of the water pricing system, the impact of increases in water pricing on households and pricing as a driver of water conservation. The study was conducted in 2009 during a time of severe drought and mandatory water restrictions. The results did not show a general aversion to all aspects of price increases but rather different sectors of the population were particularly resistant to different, specific aspects of water pricing. A state-wide water pricing policy in South Australia means that all consumers pay the same rate per volume of water consumed regardless of their location; yet in the regional study area, where it costs more for the service provider to supply the water, the respondents had stronger feelings that the price of water should be higher in places where it costs more to supply it. Generally, low income earners were less in favor of a block pricing system than higher income earners. The latter findings indicate a common lack of awareness around various aspects of water pricing. Some implications of the findings for water managers are outlined. Water 2013-02-04 5 1 Article 10.3390/w5010197 197 223 2073-4441 2013-02-04 doi: 10.3390/w5010197 Eileen Willis Meryl Pearce Loreen Mamerow Bradley Jorgensen John Martin http://www.mdpi.com/2073-4441/5/1/94 Membrane distillation is a process that utilizes differences in vapor pressure to permeate water through a macro-porous membrane and reject other non-volatile constituents present in the influent water. This review considers the fundamental heat and mass transfer processes in membrane distillation, recent advances in membrane technology, module configurations, and the applications and economics of membrane distillation, and identifies areas that may lead to technological improvements in membrane distillation as well as the application characteristics required for commercial deployment. Water 2013-01-25 5 1 Review 10.3390/w5010094 94 196 2073-4441 2013-01-25 doi: 10.3390/w5010094 Lucy Camacho Ludovic Dumée Jianhua Zhang Jun-de Li Mikel Duke Juan Gomez Stephen Gray http://www.mdpi.com/2073-4441/5/1/67 The Spanish climate is full of contrasts, with torrential rains and long droughts; under these conditions, appropriate water management is essential. In Spain, until the end of the twentieth century, water management and legislative development lagged behind other more developed countries. Nowadays, great efforts are being made to reverse this situation and improve both water management and legislation in order to control the two main problems related to stormwater management in cities: floods and diffuse pollution. In this context, Sustainable Urban Drainage Systems (SUDS) were developed as the main solution to these problems. The study of these techniques started in the 1970s in the USA, but they were not studied in Spain until 1993 when the University of Cantabria and CLABSA started to look into solutions for stormwater management. After 20 years of research and application, sustainable drainage in Spain is still behind other countries in spite of the efforts to change this situation, notably by the University of Cantabria with 10 years of experience in these techniques, mainly regarding pervious pavements, where more than 13 related research projects have been carried out. The future challenges focus on the application of pervious pavements for Urban Hydrological Rehabilitation. Water 2013-01-23 5 1 Review 10.3390/w5010067 67 93 2073-4441 2013-01-23 doi: 10.3390/w5010067 Daniel Castro-Fresno Valerio Andrés-Valeri Luis Sañudo-Fontaneda Jorge Rodriguez-Hernandez http://www.mdpi.com/2073-4441/5/1/53 Stormwater runoff from highways is a source of pollution to surface water bodies and groundwater. Excess loadings of phosphorus in stormwater discharged to surface water bodies can result in eutrophication. Treatment of stormwater for phosphorus is necessary in order to sustain ecological and economical benefits related to aquatic resources. If phosphorus is removed, the water can be sustained for other uses, such as irrigation and industrial applications. The data presented in this paper is used to evaluate the treatment performance of a roadside biosorption activated media system with regards to the removal of total phosphorus and soluble reactive phosphorus from highway runoff. The evaluation also compares removal efficiencies and effluent concentrations using biosorption activated media (BAM) to that with sandy soil commonly found in the Florida area. The results presented in this paper indicate that BAM bio-filtration systems are a feasible treatment method for removing phosphorus from highway runoff. A discussion concerning the additional treatment and reuse of water by harvesting, as part of a Bio-filtration & Harvesting Swale System, is also presented in the paper. Water 2013-01-16 5 1 Article 10.3390/w5010053 53 66 2073-4441 2013-01-16 doi: 10.3390/w5010053 Andrew Hood Manoj Chopra Martin Wanielista http://www.mdpi.com/2073-4441/5/1/29 Urban stormwater infrastructure traditionally promoted conveyance. Cities are increasingly designing stormwater infrastructure that integrates both conveyance and infiltration in hybrid systems to achieve public health, safety, environmental, and social goals. In addition, cities face decisions about distribution of responsibilities for stormwater management and maintenance between institutions and landowners. Hybrid governance structures combine centralized and distributed management to facilitate planning, operations, funding, and maintenance. Effective governance in any management approach will require changes in the expertise of stormwater agencies. Recognizing the distinction between hybrid infrastructure and hybrid governance is important in long-term planning decisions for construction and management of stormwater systems. A framework is presented that relates the level and type of existing stormwater infrastructure with available capital, institutional development, and predominant citizen contributions. Cities with extensive existing infrastructure are increasingly integrating distributed, “green” approaches that promote infiltration, and must improve institutional expertise for governance decisions. For cities with little existing infrastructure, landowner management often dominates, especially when municipalities cannot keep pace with rapid growth. In between, rapidly industrializing cities are positioned to use growing capital resources to fund both conveyance and infiltration measures based on current design principles. For all cities, local management innovations, including decisions regarding public engagement, will be critical in shaping future urban stormwater systems. Water 2013-01-14 5 1 Article 10.3390/w5010029 29 52 2073-4441 2013-01-14 doi: 10.3390/w5010029 Erik Porse http://www.mdpi.com/2073-4441/5/1/13 Bioretention cells are an urban stormwater management technology used to address both water quality and quantity concerns. A lack of region-specific design guidelines has limited the widespread implementation of bioretention cells, particularly in cold climates. In this paper, experimental data are used to construct a multiple linear regression model to predict hydrological performance of bioretention cells. Nine different observed parameters are considered as candidates for regressors, of which inlet runoff volume and duration, and initial soil moisture were chosen. These three variables are used to construct six different regression models, which are tested against the observations. Statistical analysis showed that the amount of runoff captured by a bioretention cell can be successfully predicted by the inlet runoff volume and event duration. Historical data is then used to calculate runoff volume for a given duration, in different catchment types. This data is used in the regression model to predict bioretention cell performance. The results are then used to create a design tool which can assist in estimating bioretention cell size to meet different performance goals in southern Alberta. Examples on the functionality of the design tool are provided. Water 2013-01-08 5 1 Article 10.3390/w5010013 13 28 2073-4441 2013-01-08 doi: 10.3390/w5010013 Usman Khan Caterina Valeo Angus Chu Jianxun He http://www.mdpi.com/2073-4441/5/1/1 Combined sewer systems are designed to transport stormwater surface run off in addition to the dry weather flows up to defined limits. In most European countries, hydraulic loads greater than the design flow are discharged directly into receiving water bodies, with minimal treatment (screening, sedimentation), or with no treatment at all. One feasible solution to prevent receiving waters from strong negative impacts seems to be the application of vertical flow constructed wetlands. In Germany, first attempts to use this ecological technology were recognized in early 1990s. Since then, further development continued until a high level of treatment performance was reached. During recent years the national “state-of-the-art” (defined in 2005) was adapted in other European countries, including France and Italy. Against the background of differing national requirements in combined sewer system design, substantial developmental steps were taken. The use of coarser filter media in combination with alternating loadings of separated filter beds allows direct feedings with untreated combined runoff. Permanent water storage in deep layers of the wetland improves the system’s robustness against extended dry periods, but contains operational risks. Besides similar functions (but different designs and layouts), correct dimensioning of all approaches suffers from uncertainties in long-term rainfall predictions as well as inside sewer system simulation tools. Water 2012-12-24 5 1 Article 10.3390/w5010001 1 12 2073-4441 2012-12-24 doi: 10.3390/w5010001 Daniel Meyer Pascal Molle Dirk Esser Stéphane Troesch Fabio Masi Ulrich Dittmer http://www.mdpi.com/2073-4441/4/4/1025 The excessive use of water is damaging European groundwater and rivers: their environmental conditions are often below the “good status” that—according to Water Framework Directive 2000/60—should be reached by 2015. The already critical situation is tending to get worse because of climate change. Even in water rich countries, urban wastewater is still one of the main sources of water pollution. Currently, urban soil sealing and “conventional” rainwater management, which were planned to quickly move rainwater away from roofs and streets, are increasing the flood risk. “Green” technologies and approaches would permit a reduction in water abstraction and wastewater production while improving urban hydrological response to heavy rains. The Life+ WATACLIC project has been implemented to promote such sustainable technologies and approaches in Italy, however the results show huge difficulties: apparently water saving and sustainable urban water management have only low interest amongst the general public and even with public administrations and the relevant industrial sectors. In such a cultural and technical context, the project is bringing a new point of view to public debate. In the long term, the project will certainly have a positive impact, but most likely it will require more time than initially expected. Water 2012-12-19 4 4 Article 10.3390/w4041025 1025 1038 2073-4441 2012-12-19 doi: 10.3390/w4041025 Giulio Conte Andrea Bolognesi Cristiana Bragalli Sara Branchini Alessandro Carli Chiara Lenzi Fabio Masi Antonio Massarutto Marco Pollastri Ilaria Principi http://www.mdpi.com/2073-4441/4/4/1009 Use and retention of river water in African highlands deprive communities in arid lowlands of their benefits. This paper reviews information on water use in the Ewaso Ng’iro catchment, Kenya, to evaluate the effects of upstream abstraction on the Lorian Swamp, a wetland used by pastoralists downstream. We first assess the abstractions and demands for water upstream and the river water supplies at the upper and the lower end of the Lorian Swamp. Further analysis of 12 years of monthly SPOT-VEGETATION satellite imagery reveals higher NDVI (Normalized Differential Vegetation Index) values in the swamp than nearby rainfed areas, with the difference in NDVI between the two positively related to river water discharged into the swamp. The paper next reviews the benefits derived from water entering the swamp and the vulnerability to abstractions for three categories of water: (i) the surface water used for drinking and sanitation; (ii) the surface water that supports forage production; and (iii) the water that recharges the Merti Aquifer. Our results suggest that benefits from surface water for domestic use and forage production are vulnerable to abstractions upstream whereas the benefits from the aquifer, with significant fossil water, are likely to be affected in the long run, but not the short term. Water 2012-12-19 4 4 Article 10.3390/w4041009 1009 1024 2073-4441 2012-12-19 doi: 10.3390/w4041009 Jan De Leeuw Mohammed Y. Said Shem Kifugo Zipporah Musyimi Jeniffer K. Mutiga Don Peden http://www.mdpi.com/2073-4441/4/4/995 This study examined the effectiveness of open-joint inter-locking pavers in a permeable pavement in cold (winter) conditions. A field-scale inter-locking paver cell (UNI Eco-Optiloc®) was built to evaluate the hydraulic performance and water quality improvements experienced during freeze-thaw and frozen conditions in Calgary, Alberta, Canada. Hydraulic performance was assessed using stormwater runoff reduction (peaks and volumes) and surface infiltration capacity. Water quality performance for removal of total suspended solids (TSS), total nitrogen (TN), total phosphorous (TP) and three heavy metals: copper, lead and zinc, was assessed. Results from the study demonstrated that the inter-locking pavers were effective in attenuating stormwater runoff peak volumes. The surface infiltration capacity decreased significantly due to the deposition of sanding and de-icing materials on the pavement surface during winter operation. Infiltrated stormwater was stored and treated within the pavement structure, which showed removal rates of 91% for TSS, 78% for TP, 6% for TN, 68% for zinc, 69% for copper and 55% for lead. Water 2012-12-17 4 4 Article 10.3390/w4040995 995 1008 2073-4441 2012-12-17 doi: 10.3390/w4040995 Jian Huang Caterina Valeo Jianxun He Angus Chu http://www.mdpi.com/2073-4441/4/4/983 Hydraulic fracturing is an industrial process used to extract fossil fuel reserves that lie deep underground. With the introduction of horizontal drilling, new commercial sources of energy have become available. Wells are drilled and injected with large quantities of water mixed with specially selected chemicals at high pressures that allow petroleum reserves to flow to the surface. While the increased economic activities and the outputs of domestic energy are welcomed, there is growing concern over negative environmental impacts from horizontal drilling in shale formations. The potential for water contamination, land destruction, air pollution, and geologic disruption has raised concerns about the merits of production activities used during extraction. This paper looks at the impacts of horizontal drilling using hydraulic fracturing on water supplies and takes a comprehensive look at legislative and regulatory approaches to mitigate environmental risks in the Marcellus shale region. The overview identifies shortcomings associated with regulatory controls by local and state governments and offers two policy suggestions to better protect waters of the region. Water 2012-12-04 4 4 Article 10.3390/w4040983 983 994 2073-4441 2012-12-04 doi: 10.3390/w4040983 Heather Hatzenbuhler Terence Centner http://www.mdpi.com/2073-4441/4/4/959 Many agriculture-based economies are increasingly under stress from climate change and socio-economic pressures. The excessive exploitation of natural resources still represents the standard procedure to achieve socio-economic development. In the area of the Moulouya river basin, Morocco, natural water availability represents a key resource for all economic activities. Agriculture represents the most important sector, and frequently occurring water deficits are aggravated by climate change. On the basis of historical trends taken from CRU TS 2.1, this paper analyses the impact of climate change on the per capita water availability under inclusion of population trends. The Climatic Water Balance (CWB) shows a significant decrease for the winter period, causing adverse effects for the main agricultural season. Further, moisture losses due to increasing evapotranspiration rates indicate problems for the annual water budget and groundwater recharge. The per capita blue water availability falls below a minimum threshold of 500 m3 per year, denoting a high regional vulnerability to increasing water scarcity assuming a no-response scenario. Regional development focusing on the water-intense sectors of agriculture and tourism appears to be at risk. Institutional capacities and policies need to address the problem, and the prompt implementation of innovative water production and efficiency measures is recommended. Water 2012-12-03 4 4 Article 10.3390/w4040959 959 982 2073-4441 2012-12-03 doi: 10.3390/w4040959 Vera Tekken Jürgen Kropp http://www.mdpi.com/2073-4441/4/4/944 Due to greater demands for hydrocarbons and improvements in drilling technology, development of oil and natural gas in some regions of the United States has increased dramatically. A 1.4 ha natural gas well pad was constructed in an intermittent stream channel at the Alto Experimental Watersheds in East Texas, USA (F1), while another 1.1 ha well pad was offset about 15 m from a nearby intermittent stream (F2). V-notch weirs were constructed downstream of these well pads and stream sedimentation and water quality was measured. For the 2009 water year, about 11.76 cm, or almost 222% more runoff resulted from F1 than F2. Sediment yield was significantly greater at F1, with 13,972 kg ha−1 yr−1 versus 714 kg ha−1yr−1 at F2 on a per unit area disturbance basis for the 2009 water year. These losses were greater than was observed following forest clearcutting with best management practices (111–224 kg ha−1). Significantly greater nitrogen and phosphorus losses were measured at F1 than F2. While oil and gas development can degrade surface water quality, appropriate conservation practices like retaining streamside buffers can mitigate these impacts. Water 2012-11-20 4 4 Article 10.3390/w4040944 944 958 2073-4441 2012-11-20 doi: 10.3390/w4040944 Matthew McBroom Todd Thomas Yanli Zhang http://www.mdpi.com/2073-4441/4/4/932 Enzymatic modification of polyethersulfone (PES) membranes has been found not only feasible, but also an environmentally attractive way to vary surface properties systematically. In this paper, we summarize the effect of modification layers on protein adsorption and bacterial adhesion on PES membranes and surfaces. The enzyme laccase was used to covalently bind (poly)phenolic acids to the membrane, and compared to other membrane modification methods, this method is very mild and did not influence the mechanical strength negatively. Depending on the conditions used during modification, the modification layers were capable of influencing interactions with typical fouling species, such as protein, and to influence attachment of microorganisms. We also show that the modification method can be successfully applied to hollow fiber membranes; and depending on the pore size of the base membrane, proteins were partially rejected by the membrane. In conclusion, we have shown that enzymatic membrane modification is a versatile and economically attractive method that can be used to influence various interactions that normally lead to surface contamination, pore blocking, and considerable flux loss in membranes. Water 2012-11-16 4 4 Article 10.3390/w4040932 932 943 2073-4441 2012-11-16 doi: 10.3390/w4040932 Norhan Nady Maurice Franssen Han Zuilhof Remko Boom Karin Schroën http://www.mdpi.com/2073-4441/4/4/914 Green roofs, which have been used for several decades in many parts of the world, offer a unique and sustainable approach to stormwater management. Within this paper, evidence is presented on water retention for an irrigated green roof system. The presented green roof design results in a water retention volume on site. A first principle mass balance computer model is introduced to assist with the design of these green roof systems which incorporate a cistern to capture and reuse runoff waters for irrigation of the green roof. The model is used to estimate yearly stormwater retention volume for different cistern storage volumes. Additionally, the Blaney and Criddle equation is evaluated for estimation of monthly evapotranspiration rates for irrigated systems and incorporated into the model. This is done so evapotranspiration rates can be calculated for regions where historical data does not exist, allowing the model to be used anywhere historical weather data are available. This model is developed and discussed within this paper as well as compared to experimental results. Water 2012-11-13 4 4 Article 10.3390/w4040914 914 931 2073-4441 2012-11-13 doi: 10.3390/w4040914 Mike Hardin Martin Wanielista Manoj Chopra http://www.mdpi.com/2073-4441/4/4/905 Land management and natural resource public policy decision-making in the United States can benefit from two resource damage/recovery concepts: ecosystem service (ES) and critical load (CL). The purpose of this paper is to suggest an integrated approach to the application of ES and CL principles for public land management and natural resource policy decision-making. One well known example that is appropriate for ES and CL evaluation is examined here: the acidification of soil and drainage water by atmospheric deposition of acidifying sulfur and nitrogen compounds. A conceptual framework illustrates how the ES and CL approaches can be combined in a way that enhances the strengths of each. This framework will aid in the process of translating ES and CL principles into land management and natural resource policy decision-making by documenting the impacts of pollution on environmental goods and services that benefit humans. Water 2012-11-13 4 4 Article 10.3390/w4040905 905 913 2073-4441 2012-11-13 doi: 10.3390/w4040905 Timothy J. Sullivan http://www.mdpi.com/2073-4441/4/4/887 The Federal State of Saxony (Germany) transposed the EU Water Framework Directive into state law, identifying 617 surface water bodies (rivers and streams) for implementation of the water framework directive (WFD). Their ecological status was classified by biological quality elements (macrophytes and phytobenthos, benthic invertebrates and fish, and in large rivers, phytoplankton) and specific synthetic and non-synthetic pollutants. Hydromorphological and physico-chemical quality elements were used to identify significant anthropogenic pressures, which surface water bodies are susceptible to, and to assess the effect of these pressures on the status of surface water bodies. In 2009, the data for classification of the ecological status and the main pressures and impacts on water bodies were published in the river basin management plans (RBMP) of the Elbe and Oder rivers. To that date, only 23 (4%) streams achieved an ecological status of “good”, while the rest failed to achieve the environmental objective. The two main reasons for the failure were significant alterations to the stream morphology (81% of all streams) and nutrient enrichment (62%) caused by point (industrial and municipal waste water treatment plants) and non-point (surface run-off from arable fields, discharges from urban drainages and decentralized waste water treatment plants) sources. It was anticipated that a further 55 streams would achieve the environmental objective by 2015, but the remaining 539 need extended deadlines. Water 2012-11-09 4 4 Article 10.3390/w4040887 887 904 2073-4441 2012-11-09 doi: 10.3390/w4040887 Bernd Spänhoff Roland Dimmer Holm Friese Steve Harnapp Frank Herbst Kerstin Jenemann Antje Mickel Sylvia Rohde Michaela Schönherr Katrin Ziegler Karin Kuhn Uwe Müller http://www.mdpi.com/2073-4441/4/4/869 This paper presents a simple approach for estimating the spatial and temporal variability of seasonal net irrigation water requirement (IWR) at the catchment scale, based on gridded land use, soil and daily weather data at 500 × 500 m resolution. In this approach, IWR is expressed as a bounded, linear function of the atmospheric water budget, whereby the latter is defined as the difference between seasonal precipitation and reference evapotranspiration. To account for the effects of soil and crop properties on the soil water balance, the coefficients of the linear relation are expressed as a function of the soil water holding capacity and the so-called crop coefficient. The 12 parameters defining the relation were estimated with good coefficients of determination from a systematic analysis of simulations performed at daily time step with a FAO-type point-scale model for five climatically contrasted sites around the River Rhone and for combinations of six crop and ten soil types. The simple scheme was found to reproduce well results obtained with the daily model at six additional verification sites. We applied the simple scheme to the assessment of irrigation requirements in the whole Swiss Rhone catchment. The results suggest seasonal requirements of 32 × 106 m3 per year on average over 1981–2009, half of which at altitudes above 1500 m. They also disclose a positive trend in the intensity of extreme events over the study period, with an estimated total IWR of 55 × 106 m3 in 2009, and indicate a 45% increase in water demand of grasslands during the 2003 European heat wave in the driest area of the studied catchment. In view of its simplicity, the approach can be extended to other applications, including assessments of the impacts of climate and land-use change. Water 2012-11-07 4 4 Article 10.3390/w4040869 869 886 2073-4441 2012-11-07 doi: 10.3390/w4040869 Pascalle C. Smith Pierluigi Calanca Jürg Fuhrer http://www.mdpi.com/2073-4441/4/4/848 Ensuring water availability for multiple needs represents a sustainable development challenge globally. Rigid planning for fixed water supply and reuse targets with estimated demand growth and static assumptions of water availability can prove inflexible in responding to changing conditions. Formal methods to adaptively respond to these challenges are needed, particularly in regions with limited natural resources and/or where multiple uncertain forces can influence water-resource availability and supply reliability. This paper assesses the application of Scenario Planning in one such region—Tucson, Arizona, USA—over the coming 40 years, and highlights broader lessons for addressing complex interrelationships of water management, infrastructure development, and population growth. Planners from multiple jurisdictions and researchers identified ten key forces and prioritized three with the greatest uncertainty and the greatest impact for water and development planning: (1) changing demands based on potential future density, layout, and per capita water use/reuse; (2) adequacy of current water supplies to meet future demands; and (3) evolving public perceptions of water reuse including potential options to supplement potable water supplies. Detailed scenario modeling using GIS and infrastructure cost optimization is under development and is now beginning to produce results, to be discussed in future publications. The process has clearly demonstrated the value of Scenario Planning as a tool for bringing stakeholders into agreement over highly complex and historically divisive problems, and for prioritizing amongst diverse uncertainties. The paper concludes by characterizing possible outcomes for this case and draws lessons for other water scarce regions experiencing rapid development. Water 2012-11-05 4 4 Article 10.3390/w4040848 848 868 2073-4441 2012-11-05 doi: 10.3390/w4040848 Christopher A. Scott Christopher J. Bailey Ralph P. Marra Gwendolyn J. Woods Kerri Jean Ormerod Kevin Lansey http://www.mdpi.com/2073-4441/4/4/835 Stormwater has been recognised as one of the additional/alternative sources of water to augment freshwater supply and address the growing needs of humankind. South Australia has been a leader in the development of large-scale urban stormwater harvesting schemes in Australia for nearly 50 years and the Salisbury Local Government Area (LGA), in particular, is at the forefront of urban stormwater management and recycling, not only in the state of South Australia, but worldwide. This is mainly due to its pioneering achievements in stormwater capture and treatment through the managed aquifer recharge (MAR) process. However, there are many challenges in implementing water reuse strategies and past studies have identified public health concerns and public acceptance as major challenges. In line with this, our team conducted an internet survey to gauge the attitude and intentions of Salisbury LGA residents to use stormwater treated through the MAR process for non-potable uses. We found that respondents’ emotions and perceptions of health risk, regarding the use of treated stormwater, were closely related to the proximity of the end use to human contact. In terms of quality indicators, colour, odour, and salt levels were all seen as being important. Quality preferences were also closely related to the proximity of the end use to human contact, and reflected the use of water for indoor/outdoor purposes. Water 2012-10-25 4 4 Article 10.3390/w4040835 835 847 2073-4441 2012-10-25 doi: 10.3390/w4040835 Zhifang Wu Jennifer McKay Ganesh Keremane http://www.mdpi.com/2073-4441/4/4/815 The renewable energy emerged as a solution to the environmental problems caused by the conventional sources of energy. Small hydropower (SHP) is claimed to cause negligible effects on the ecosystem, although some environmental values are threatened and maintenance of an adequate water quality should be ensured. This work provides a characterization of the water quality status in a river stretch around a SHP plant on river Lérez, northwest Spain, for four years after its construction. The ecological and chemical status of the water as well as the ecological quality of the riparian habitat, were used as measures of quality. Data were compared with the water quality requirements. The variations in the quality parameters were analyzed over time and over the river sections with respect to the SHP plant elements. Two years after construction, the temperature and dissolved oxygen values achieved conditions for salmonid water and close to the reference condition, while pH values were low. The Iberian Biological Monitoring Working Party (IBMWP) index showed a positive trend from two years after the construction and stabilized at “unpolluted or not considerably altered water”. Quality parameters did not present significant differences between sampling points. The SHP plant construction momentarily altered the quality characteristics of the water. Water 2012-10-15 4 4 Article 10.3390/w4040815 815 834 2073-4441 2012-10-15 doi: 10.3390/w4040815 Enrique Valero http://www.mdpi.com/2073-4441/4/4/793 Two small subarctic lakes were eutrophicated due to wastewater discharge from 1964. In 1975, a wastewater treatment plant was built and a recovery process started. This paper will: (1) compile the 1972–1974, 1978–1980 and 1985–1988 investigation data regarding phosphorous and microalgae for one of the lakes; (2) complement with unpublished data from 1985 and 2003; and (3) introduce a discussion regarding three alternatives for future development of the lakes in their last phase of recovery. In the latest investigation, 2003, the lakes were assessed as almost recovered. They had returned to an oligotrophic state, but not fully to a pre-sewage situation. In the upper lake, more heavily polluted, the total phosphorous levels had decreased from an average of 168 µg P/L in 1972–1974 to an average of 12 µg P/L in 2003. The phytoplankton biomass had decreased twentyfold during the same period, from 11.2 mg/L to 0.6 mg/L. The Secchi depth had increased from 1.3 m to 2.8 m. The low oxygen level in late winter was still not recovered, thereby profoundly affecting residential organisms in the lakes. The low winter oxygen is assumed to remain so for a long time due to phosphorus release from sediments in the lakes. Water 2012-10-15 4 4 Article 10.3390/w4040793 793 814 2073-4441 2012-10-15 doi: 10.3390/w4040793 Erik Grönlund http://www.mdpi.com/2073-4441/4/4/785 Recent flood-related disasters (Japan, Thailand, US, Australia) emphasize the need for an effective management of flood risks. As an introduction to this special issue, this editorial summarizes some of the key challenges in the field. Flood risk management needs to recognize the interconnections between infrastructures, economic systems and the role of human factors in assessing and managing the risk. The challenge for flood management in the future is to develop robust and resilient solutions that perform well in uncertain future conditions. Water 2012-10-12 4 4 Editorial 10.3390/w4040785 785 792 2073-4441 2012-10-12 doi: 10.3390/w4040785 Sebastiaan Jonkman Richard Dawson http://www.mdpi.com/2073-4441/4/4/770 The biosorption potential of three fungal waste-biomasses (Acremonium strictum, Acremonium sp. and Penicillium sp.) from pharmaceutical companies was compared with that of a selected biomass (Cunninghamella elegans), already proven to be very effective in dye biosorption. Among the waste-biomasses, A. strictum was the most efficient (decolorization percentage up to 90% within 30 min) with regard to three simulated dye baths; nevertheless it was less active than C. elegans which was able to produce a quick and substantial decolorization of all the simulated dye baths (up to 97% within 30 min). The biomasses of A. strictum and C. elegans were then tested for the treatment of nine real exhausted dye baths. A. strictum was effective at acidic or neutral pH, whereas C. elegans confirmed its high efficiency and versatility towards exhausted dye baths characterised by different classes of dyes (acid, disperse, vat, reactive) and variation in pH and ionic strength. Finally, the effect of pH on the biosorption process was evaluated to provide a realistic estimation of the validity of the laboratory results in an industrial setting. The C. elegans biomass was highly effective from pH 3 to pH 11 (for amounts of adsorbed dye up to 1054 and 667 mg of dye g−1 biomass dry weight, respectively); thus, this biomass can be considered an excellent and exceptionally versatile biosorbent material. Water 2012-10-12 4 4 Article 10.3390/w4040770 770 784 2073-4441 2012-10-12 doi: 10.3390/w4040770 Valeria Prigione Irene Grosso Valeria Tigini Antonella Anastasi Giovanna Varese http://www.mdpi.com/2073-4441/4/4/759 From the viewpoint of combating global warming in Japan, measures to reduce emissions from the activities involved in daily life have been accelerated in concurrence with the efforts made in the industrial sector to save energy. As one such measure, the reduction of energy consumption in waterworks and sewer systems by reducing the volume of water used in the housing sector is gaining attention; measures for the conversion of water saving into CO2 reduction credit in the domestic credit system are also being examined. To address the credit development for CO2 reduction by water saving, it was necessary to determine the CO2 emission factor for water. Hence, we calculated the CO2 emission factor of water use in Japan and determined the value to be 0.376 kg CO2/m3 which applied the generating end electricity value. In addition, since electricity contributes to 90% of the energy consumption of the waterworks and sewer systems of Japan and since the emission factor for electricity changes with the power source composition ratio, the CO2 emission factor for water also needs to be updated to match the emission factor for electricity. We therefore developed a calculation equation for updating this emission factor. Water 2012-09-28 4 4 Article 10.3390/w4040759 759 769 2073-4441 2012-09-28 doi: 10.3390/w4040759 Yasutoshi Shimizu Satoshi Dejima Kanako Toyosada http://www.mdpi.com/2073-4441/4/3/739 Often centralized water supply, sanitation and solid waste services struggle to keep up with the rapid expansion of urban areas. The peri-urban areas are at the forefront of this expansion and it is here where decentralized technologies are increasingly being implemented. The introduction of decentralized technologies allows for the development of new opportunities that enable the recovery and reuse of resources in the form of water, nutrients and energy. This resource-oriented management of water, nutrients and energy requires a sustainable system aimed at low resource use and high recovery and reuse rates. Instead of investigating each sector separately, as has been traditionally done, this article proposes and discusses a concept that seeks to combine the in- and outflows of the different sectors, reusing water and other liberated resources where possible. This paper shows and demonstrates examples of different types of sustainable technologies that can be implemented in the peri-urban areas of Mexico City [rainwater harvesting, EcoSan and biofiltros (small constructed wetlands), and (vermi-)composting]. An innovative participatory planning method, combining scenario development with a participatory planning workshop with key stakeholders, was applied and resulted in three concept scenarios. Specific technologies were then selected for each concept scenario that the technical feasibility and applicability was assessed. Following this, the resulting resource flows (nutrients, water and energy) were determined and analyzed. The results show that decentralized technologies not only have the potential to deliver adequate water supply, sanitation and solid waste services in peri-urban areas and lessen environmental pollution, but also can recover significant amounts of resources thereby saving costs and providing valuable inputs in, for instance, the agricultural sector. Social acceptance of the technologies and institutional cooperation, however, is key for successful implementation. Water 2012-09-24 4 3 Article 10.3390/w4030739 739 758 2073-4441 2012-09-24 doi: 10.3390/w4030739 Tiemen A. Nanninga Iemke Bisschops Eduardo López José Luis Martínez-Ruiz Daniel Murillo Laura Essl Markus Starkl http://www.mdpi.com/2073-4441/4/3/720 An experimental study was performed to investigate the behavior of inclined negatively buoyant jets. Such jets arise when brine is discharged from desalination plants. A turbulent jet with a specific salinity was discharged through a circular nozzle at an angle to the horizontal into a tank with fresh water and the spatial evolution of the jet was recorded. Four different initial jet parameters were changed, namely the nozzle diameter, the initial jet inclination, the jet density and the flow rate. Five geometric quantities describing the jet trajectory that are useful in the design of brine discharge systems were determined. Dimensional analysis demonstrated that the geometric jet quantities studied, if normalized with the jet exit diameter, could be related to the densimetric Froude number. Analysis of the collected data showed that this was the case for a Froude number less than 100, whereas for larger values of the Froude number the scatter in the data increased significantly. As has been observed in some previous investigations, the slope of the best-fit straight line through the data points was a function of the initial jet angle (θ), where the slope increased with θ for the maximum levels (Ym) studied, but had a more complex behavior for horizontal distances. Water 2012-09-24 4 3 Article 10.3390/w4030720 720 738 2073-4441 2012-09-24 doi: 10.3390/w4030720 Raed Bashitialshaaer Magnus Larson Kenneth M. Persson http://www.mdpi.com/2073-4441/4/3/707 Although groundwater quality depends on microbial processes in the soil treatment area (STA) of onsite wastewater treatment systems (OWTS), our understanding of the development of these microbial communities is limited. We examined the bacterial communities of sand, sandy loam, and clay STAs at different depths in response to septic tank effluent (STE) addition using mesocosms. Terminal restriction fragment length polymorphism (TRFLP) analysis was used to compare the bacterial community structure and composition of STE, native soil prior to STE addition (UNX) and soil exposed to STE (EXP). Principal component analysis separated communities with depth in sand but not in sandy loam or clay. Indices of richness, diversity, and evenness followed the order: sandy loam > sand > clay. Analysis of TRF peaks indicated that STE contributed least to the composition of STA bacterial communities (5%–16%), followed by UNX soil (18%–48%), with the highest proportion of the community made up of TRFs not detected previously in either UNX or STE (50%–82%) for all three soils. Soil type and depth can have a marked effect on the structure and composition of STA bacterial communities, and on the relative contribution of native soil and STE to these communities. Water 2012-09-17 4 3 Article 10.3390/w4030707 707 719 2073-4441 2012-09-17 doi: 10.3390/w4030707 Jose A. Amador Janet A. Atoyan http://www.mdpi.com/2073-4441/4/3/690 Desalination of brackish groundwater (BW) is an effective approach to augment water supply, especially for inland regions that are far from seawater resources. Brackish water reverse osmosis (BWRO) desalination is still subject to intensive energy consumption compared to the theoretical minimum energy demand. Here, we review some of the BWRO plants with various system arrangements. We look at how to minimize energy demands, as these contribute considerably to the cost of desalinated water. Different configurations of BWRO system have been compared from the view point of normalized specific energy consumption (SEC). Analysis is made at theoretical limits. The SEC reduction of BWRO can be achieved by (i) increasing number of stages, (ii) using an energy recovery device (ERD), or (iii) operating the BWRO in batch mode or closed circuit mode. Application of more stages not only reduces SEC but also improves water recovery. However, this improvement is less pronounced when the number of stages exceeds four. Alternatively and more favourably, the BWRO system can be operated in Closed Circuit Desalination (CCD) mode and gives a comparative SEC to that of the 3-stage system with a recovery ratio of 80%. A further reduction of about 30% in SEC can be achieved through batch-RO operation. Moreover, the costly ERDs and booster pumps are avoided with both CCD and batch-RO, thus furthering the effectiveness of lowering the costs of these innovative approaches. Water 2012-09-17 4 3 Article 10.3390/w4030690 690 706 2073-4441 2012-09-17 doi: 10.3390/w4030690 Tianyu Qiu Philip A. Davies http://www.mdpi.com/2073-4441/4/3/683 The application of mussel spat rope for enabling the passage of redfin bully Gobiomorphus huttoni through culverts, which create velocity barriers, was trialled in the laboratory. No fish were able to access the un-roped control pipes whereas 52% successfully negotiated the pipes in the rope treatments. The success of fish ascending treatment pipes suggests mussel spat rope may be effective for enabling the passage of this and other similar fish species through otherwise impassable culverts with velocity barriers. Water 2012-09-14 4 3 Short Note 10.3390/w4030683 683 689 2073-4441 2012-09-14 doi: 10.3390/w4030683 Jonathan D. Tonkin Liam A.H. Wright Bruno O. David http://www.mdpi.com/2073-4441/4/3/670 Without monitoring anthropogenic pressures on the water environment, it is difficult to set realistic river restoration targets in relation to water quality. Therefore a more holistic approach is needed to systematically explore the links between socio-economic drivers and observed water quality-related impacts on river ecosystems. Using the DPSIR (Drivers-Pressures-State of the Environment-Impacts-Responses) framework, this study linked ecological river restoration with the socio-economic sector, with the focus on promoting a pressure-oriented water quality monitoring system. Based on the European Water Framework Directive (WFD) and relevant literature, it was found that most water quality-related indicators employed today are state/impacts-oriented, while very few are pressure-oriented. As a response, we call for more attention to a DPR (Drivers-Pressures-Responses) framework in developing an industrial ecology-based pressure-oriented water quality monitoring system for aiding ecological river restoration planning. This approach is characterized in general by accounting for material-related flows throughout the socio-economic sector in relation to river ecosystem degradation. Then the obtained information would help decision makers take appropriate measures to alleviate various significant human-induced wastes and emissions at their sources. We believe that such a pressure-oriented monitoring system will substantially complement traditional state/impacts-oriented environmental and ecological monitoring and help develop more proactive planning and decision-making processes for specific river restoration projects and general water quality management. Water 2012-09-14 4 3 Article 10.3390/w4030670 670 682 2073-4441 2012-09-14 doi: 10.3390/w4030670 Xingqiang Song Björn Frostell http://www.mdpi.com/2073-4441/4/3/650 The occurrence and removal efficiencies of the pharmaceuticals lidocaine (LDC), tramadol (TRA) and venlafaxine (VEN), and their major active metabolites monoethylglycinexylidide (MEGX), O-desmethyltramadol (ODT) and O-desmethylvenlafaxine (ODV) were studied at four wastewater treatment plants (WWTPs) equipped with activated sludge treatment technologies. In parallel to activated sludge treatment, the removal efficiency of the compounds in pilot- and full-scale projects installed at the WWTPs was investigated. Within these projects two different treatment methods were tested: adsorption onto powdered/granulated activated carbon (PAC/GAC) and ozonation. The metabolite MEGX was not detected in any sample. The concentrations of the target analytes in wastewater effluents resulting from activated sludge treatment ranged from 55 to 183 (LDC), 88 to 416 (TRA), 50 to 245 (ODT), 22 to 176 (VEN) and 77 to 520 ng L−1 (ODV). In the pilot project with subsequent treatment with PAC/GAC, the mean concentrations of the analytes were between Water 2012-09-11 4 3 Article 10.3390/w4030650 650 669 2073-4441 2012-09-11 doi: 10.3390/w4030650 Paola C. Rúa-Gómez Arlen A. Guedez Conchi O. Ania Wilhelm Püttmann http://www.mdpi.com/2073-4441/4/3/629 This review provides a global overview of microporous silica based membranes for desalination via pervaporation with a focus on membrane synthesis and processing, transport mechanisms and current state of the art membrane performance. Most importantly, the recent development and novel concepts for improving the hydro-stability and separating performance of silica membranes for desalination are critically examined. Research into silica based membranes for desalination has focussed on three primary methods for improving the hydro-stability. These include incorporating carbon templates into the microporous silica both as surfactants and hybrid organic-inorganic structures and incorporation of metal oxide nanoparticles into the silica matrix. The literature examined identified that only metal oxide silica membranes have demonstrated high salt rejections under a variety of feed concentrations, reasonable fluxes and unaltered performance over long-term operation. As this is an embryonic field of research several target areas for researchers were discussed including further improvement of the membrane materials, but also regarding the necessity of integrating waste or solar heat sources into the final process design to ensure cost competitiveness with conventional reverse osmosis processes. Water 2012-09-03 4 3 Review 10.3390/w4030629 629 649 2073-4441 2012-09-03 doi: 10.3390/w4030629 Muthia Elma Christelle Yacou David K. Wang Simon Smart João C. Diniz da Costa http://www.mdpi.com/2073-4441/4/3/607 The objective of this study is to assess the potential for potable water savings by using rainwater as well as the sizing of rainwater tanks in houses in some cities in the world. Daily rainfall data for thirteen cities located in different countries were used. Different catchment areas, number of residents, potable and rainwater demands were considered in order to assess their impact on the potential for potable water savings and sizing of rainwater tanks. The analysis was performed using the Netuno computer program. The results showed that the greatest potential for potable water savings is obtained in cities where there is constant rainfall, which does not always mean high annual average rainfall. Cities with well-defined periods of drought require larger tank capacities. Overall, it was observed that all parameters (catchment area, number of residents, potable and rainwater demands, and rainfall) influence the sizing of the tank for rainwater storage. Water 2012-08-29 4 3 Article 10.3390/w4030607 607 628 2073-4441 2012-08-29 doi: 10.3390/w4030607 Eduardo Leite Souza Enedir Ghisi http://www.mdpi.com/2073-4441/4/3/597 Inexpensive remote temperature data loggers have allowed for a dramatic increase of data describing water temperature regimes. This data is used in understanding the ecological functioning of natural riverine systems and in quantifying changes in these systems. However, an increase in the quantity of yearly temperature data necessitates complex data management, efficient summarization, and an effective data-cleaning regimen. This note focuses on identifying events where data loggers failed to record correct temperatures using data from the Sauk River in Northwest Washington State as an example. By augmenting automated checks with visual comparisons against air temperature, related sites, multiple years, and available flow data, dewatering events can be more accurately and efficiently identified. Water 2012-08-20 4 3 Technical Note 10.3390/w4030597 597 606 2073-4441 2012-08-20 doi: 10.3390/w4030597 Colin Sowder E. Ashley Steel http://www.mdpi.com/2073-4441/4/3/580 Installation of decentralized grey water treatment systems in small rural communities contributes to a more sustainable water supply. In order to gauge community attitudes about collection and use of grey water, a door-to-door survey in the farming community of Deir Alla, Jordan was conducted by Royal Scientific Society interviewers. Outcomes of a detailed survey, designed specifically for this project, offer insights on people’s views on general water and wastewater issues, as well as their motivation, practices and concerns related to using grey water treatment for a portion of their household wastewater and reuse of the treated grey water for irrigation. A total of 47 respondents from different socio-economic background, aged over 18 years, from this community in the Jordan valley took part in the survey. The level of formal education of the respondents was low, and most of households’ incomes were below the poverty line in Jordan. Most of the respondents reported that the quality of water supplied by public network is acceptable, but the quantity is insufficient to meet their demand, with supplies being delivered to the household once a week. Respondents relied on the public water network as a first-most important resource (85.1%), and 57.4% of the respondent relied on private water tankers as a second-most important resource in addition to the public network. However, 6% of the respondents relied only on private water tankers with no access to the public network. Storage tanks are common practice in all the houses in order to store enough water for at least one week. The survey responses provide evidence that rural communities are willing to accept reuse of treated grey water for irrigation. Furthermore, some of people in the studied area are willing to learn more about grey water treatment and reuse in order to operate grey water systems for irrigation purposes. Water scarcity in this rural area of Jordan is the main determinant of willingness to reuse the grey water, rather than socio-economic variables. Water 2012-08-06 4 3 Article 10.3390/w4030580 580 596 2073-4441 2012-08-06 doi: 10.3390/w4030580 Othman A. Al-Mashaqbeh Ayoup M. Ghrair Sharon B. Megdal http://www.mdpi.com/2073-4441/4/3/568 Most coastal flood risk studies make use of a Digital Elevation Model (DEM) in addition to a projected flood water level in order to estimate the flood inundation and associated damages to property and livelihoods. The resolution and accuracy of a DEM are critical in a flood risk assessment, as land elevation largely determines whether a location will be flooded or will remain dry during a flood event. Especially in low lying deltaic areas, the land elevation variation is usually in the order of only a few decimeters, and an offset of various decimeters in the elevation data has a significant impact on the accuracy of the risk assessment. Publicly available DEMs are often used in studies for coastal flood risk assessments. The accuracy of these datasets is relatively low, in the order of meters, and is especially low in comparison to the level of accuracy required for a flood risk assessment in a deltaic area. For a coastal zone area in Nigeria (Lagos State) an accurate LiDAR DEM dataset was adopted as ground truth concerning terrain elevation. In the case study, the LiDAR DEM was compared to various publicly available DEMs. The coastal flood risk assessment using various publicly available DEMs was compared to a flood risk assessment using LiDAR DEMs. It can be concluded that the publicly available DEMs do not meet the accuracy requirement of coastal flood risk assessments, especially in coastal and deltaic areas. For this particular case study, the publically available DEMs highly overestimated the land elevation Z-values and thereby underestimated the coastal flood risk for the Lagos State area. The findings are of interest when selecting data sets for coastal flood risk assessments in low-lying deltaic areas. Water 2012-07-27 4 3 Article 10.3390/w4030568 568 579 2073-4441 2012-07-27 doi: 10.3390/w4030568 Bas van de Sande Joost Lansen Claartje Hoyng http://www.mdpi.com/2073-4441/4/3/545 Assessing the vulnerability of groundwater is the first step toward careful management of water resources to avoid or, at least, to minimize impacts on agriculture. The objective of this study was to propose a simple method to assess the groundwater quality and to map its spatial variation in terms of suitability for irrigation in the Darb El-Arbaein area, Southwestern Desert, Egypt. Thirty-six surveyed wells were used to assess and map the groundwater quality. For calculating the Water Quality Index (WQI), a total of 20 (13 chemical, two physical, and five calculated) parameters were considered e.g., EC, pH, Cl, SAR, B, Zn, iron, Mn, Pb and Cd. The results of analyses were used to propose a water quality model. The different water quality maps were produced using GIS software. The results show that three water samples fall into the moderate WQI. Most of the samples (26) fall into the unsuitable WQI category. Seven samples fall into the suitable WQI category. Groundwater samples that fall into the low salinity hazard class and high WQI can be used for irrigation of most crops and the majority of soils. The WQI for the samples ranges from 47.9 to 88.6. The WQI distribution maps delineating an area of 266.66 ha are suitable for irrigation in villages (3,4) and areas of 382.35 ha are moderately suitability for villages (1,2). Since the final map shows the spatial distribution of irrigation water quality in the area, it is now much easier for a decision maker to assess the water quality for irrigation and to locate the most suitable site for drilling wells. The present study demonstrates high efficiency for GIS to analyze complex spatial data and groundwater quality mapping. Water 2012-07-24 4 3 Article 10.3390/w4030545 545 567 2073-4441 2012-07-24 doi: 10.3390/w4030545 El-Sayed E. Omran http://www.mdpi.com/2073-4441/4/3/533 Until now, as a way of reducing greenhouse gas emissions from Japanese homes, the emphasis has been on reduction of energy consumption for air-conditioning and lighting. In recent years, there has been progress in CO2 emission reduction through research into the water-saving performance of bathroom fixtures such as toilets and showers. Simulations have shown that CO2 emissions associated with water consumption in Japanese homes can be reduced by 25% (1% of Japan’s total CO2 emissions) by 2020 through the adoption of the use of water-saving fixtures. In response to this finding, a program to promote the replacement of current fixtures with water-saving toilet bowls and thermally insulated bathtubs has been added to the Government of Japan’s energy-saving policy. Furthermore, CO2 emission reduction through widespread use of water-saving fixtures has been adopted by the domestic credit system promoted by the Government of Japan as a way of achieving CO2 emission-reduction targets; application of this credit system has also begun. As part of a bilateral offset credit mechanism promoted by the Government of Japan, research to evaluate the CO2 reduction potential of the adoption of water-saving fixtures has been done in the city of Dalian, in China. Water 2012-07-09 4 3 Article 10.3390/w4030533 533 544 2073-4441 2012-07-09 doi: 10.3390/w4030533 Yasutoshi Shimizu Kanako Toyosada Mari Yoshitaka Kyosuke Sakaue http://www.mdpi.com/2073-4441/4/3/510 We examine in some detail the interaction of water molecules with the radiative electromagnetic field and find the existence of phase transitions from the vapor phase to a condensed phase where all molecules oscillate in unison, in tune with a self-trapped electromagnetic field within extended mesoscopic space regions (Coherence Domains). The properties of such a condensed phase are examined and found to be compatible with the phenomenological properties of liquid water. In particular, the observed value of critical density is calculated with good accuracy. Water 2012-07-09 4 3 Article 10.3390/w4030510 510 532 2073-4441 2012-07-09 doi: 10.3390/w4030510 Ivan Bono Emilio Del Giudice Luca Gamberale Marc Henry http://www.mdpi.com/2073-4441/4/2/496 Several studies have shown concern over nitrate and nitrite contamination of prepared infant formula used by infants less than six months old, as it may lead to methemoglobinemia and death. One possible source of contamination is through the use of improperly treated drinking water. Contamination of water could result from fertilizers and manure runoff, not fully treated and released human and industrial waste, or from disinfection processes. In the United Arab Emirates (UAE), bottled water is the major source of drinking water and may be used for the preparation of infant formula. Therefore, in this study, several bottled water brands that are sold on the UAE market, and could be used for preparation of infant formula, were tested for nitrate and nitrite and other anions to show their compatibility with the permissible levels of the United States Environmental Protection Agency (U.S. EPA), United States Food and Drug Administration/Code of Federal Regulations (U.S. FDA/CFR), and other international organizations. All the bottled water samples demonstrated nitrate, nitrite, and other anions levels below the permissible levels accepted by U.S. EPA, U.S. FDA/CFR, and other international organizations, except for one sample that showed nitrite levels exceeding the European Commission and Drinking Water Directive (EC/DWD) permissible levels. Such study sheds light on the quality of bottled water sold not only in the UAE and the region, but also in other countries, such as France, since some of them are imported. In addition, the results shed light on the effectiveness of the treatment processes and possible sources of infant formula contamination that can affect the health of infants. Water 2012-05-29 4 2 Article 10.3390/w4020496 496 509 2073-4441 2012-05-29 doi: 10.3390/w4020496 Mohamed Yehia Z. Abouleish http://www.mdpi.com/2073-4441/4/2/494 The following paragraphs are reproduced from the website of the publisher [1].Disinfection By-Products and Human Health is based on contributions from speakers who participated in May 2011 workshops on Disinfection By-Products (DBPs) and Human Health at Ozwater 11 in Adelaide, Australia or at an AWA sponsored workshop at the Curtin Water Quality Research Centre, Perth, Australia.The contributions are prepared to facilitate communication with practitioners, rather than researchers, making use of overview illustrations rather than dense text or data tables. Each chapter concludes with up to 5 key findings that are take-home messages for practitioners. [...] Water 2012-05-18 4 2 New Book Received 10.3390/w4020494 494 495 2073-4441 2012-05-18 doi: 10.3390/w4020494 Shu-Kun Lin http://www.mdpi.com/2073-4441/4/2/474 The Rhine River Delta is crucial to the Dutch economy. The Maeslant barrier was built in 1997 to protect the Rhine estuary, with the city and port of Rotterdam, from storm surges. This research takes a simple approach to quantify the influence of the Maeslant storm surge barrier on design water levels behind the barrier. The dikes in the area are supposed to be able to withstand these levels. Equal Level Curves approach is used to calculate the Rotterdam water levels by using Rhine discharges and sea water levels as input. Their joint probability function generates the occurrence frequency of a certain combination that will lead to a certain high water level in Rotterdam. The results show that the flood frequency in Rotterdam is reduced effectively with the controlled barrier in current and in future scenarios influenced by climate change. In addition, an investigation of the sensitivity of the operational parameters suggests that there is a negligible influence on the high water level frequency when the decision closing water level for the barrier is set higher due to the benefits of navigation (but not exceeding the design safety level 4 m MSL). Water 2012-05-11 4 2 Article 10.3390/w4020474 474 493 2073-4441 2012-05-11 doi: 10.3390/w4020474 Hua Zhong Peter-Jules van Overloop Pieter van Gelder Ties Rijcken http://www.mdpi.com/2073-4441/4/2/460 Microalgae can be used for the treatment of municipal wastewater. The application of microalgal biofilms in wastewater treatment systems seems attractive, being able to remove nitrogen, phosphorus and COD from wastewater at a short hydraulic retention time. This study therefore investigates the area requirement, achieved effluent concentrations and biomass production of a hypothetical large-scale microalgal biofilm system treating municipal wastewater. Three scenarios were defined: using microalgal biofilms: (1) as a post-treatment; (2) as a second stage of wastewater treatment, after a first stage in which COD is removed by activated sludge; and (3) in a symbiotic microalgal/heterotrophic system. The analysis showed that in the Netherlands, the area requirements for these three scenarios range from 0.32 to 2.1 m2 per person equivalent. Moreover, it was found that it was not possible to simultaneously remove all nitrogen and phosphorus from the wastewater, because of the nitrogen:phosphorus ratio in the wastewater. Phosphorus was limiting in the post-treatment scenario, while nitrogen was limiting in the two other scenarios. Furthermore, a substantial amount of microalgal biomass was produced, ranging from 13 to 59 g per person equivalent per day. These findings show that microalgal biofilm systems hold large potential as seasonal wastewater treatment systems and that it is worthwhile to investigate these systems further. Water 2012-04-27 4 2 Article 10.3390/w4020460 460 473 2073-4441 2012-04-27 doi: 10.3390/w4020460 Nadine C. Boelee Hardy Temmink Marcel Janssen Cees J. N. Buisman René H. Wijffels http://www.mdpi.com/2073-4441/4/2/430 This paper demonstrates a methodology for integrating existing models for the rapid simulation of coastal flood events across a large and varied case study area on the UK south coast. Following validation against observations from real coastal floods, synthetic events driven by realistic waves and water levels and the full range of failure mechanisms were modelled for a range of loadings to generate peak flood water depths and an overview of impacts across this spectrum of possible floods. Overtopping is relatively important compared to breaching as coastal floodplains are small. This modelling system supports multiple potential applications, such as planning flood warnings, coastal defence upgrade, and land use, including under sea-level rise. The concepts drawn from this study are transferable to similar coastal regions. Water 2012-04-26 4 2 Article 10.3390/w4020430 430 459 2073-4441 2012-04-26 doi: 10.3390/w4020430 Matthew P. Wadey Robert J. Nicholls Craig Hutton http://www.mdpi.com/2073-4441/4/2/389 Controversy regarding the amount of water consumed or saved as a result of human activity is currently paramount in water-scarce areas. In recent decades, golf—a land and water consuming activity—has been implanted in several areas of the Mediterranean basin, where the scarcity of water resources is well-known. As a result, the use of conventional water resources for golf course irrigation is increasingly contested and its replacement by reclaimed water has become essential. This paper examines the wide range of issues involved in its use on golf courses, including hazards—due to the presence of microorganisms and pollutants—and the corresponding risks that can appear. The resulting biological, chemical and physical water quality concerns are analyzed. Legal aspects related to the use of reclaimed water are also discussed and good reuse practices are suggested, including a detailed examination of risk assessment procedures and tools through observation or chemical, physical and microbiological analysis. The HACCP system—which focuses on quality determination in water samples from relevant control points—is described in detail, as it is generally accepted as one of the most scientific ways to detect health problems on a golf course. The paper concludes that, given the increasing availability of treated and reclaimed water and the water needs of golf courses, the future development of the sport in areas without surplus water resources—such as the Mediterranean basin—will predictably depend upon the use of reclaimed water. In recent years, risk assessment or analysis has emerged as an essential tool to guarantee the application of reclaimed water at an acceptable risk level. There certainly have been considerable advances and improvements in the tools that guarantee the safe use of reclaimed water, although current methods available require simplification for their practical application. Nevertheless, protocols applied at present seem to be adequate in order to address the key issue of enhancing the development of reclaimed water use on golf courses. Water 2012-04-11 4 2 Article 10.3390/w4020389 389 429 2073-4441 2012-04-11 doi: 10.3390/w4020389 Miquel Salgot Gerda K. Priestley Montserrat Folch http://www.mdpi.com/2073-4441/4/2/367 Recent literature outlines significant impacts from climate change on many areas of the world, with much focus on causes and impacts. However the long-term trends demand adaptation strategies. While a variety of solutions have been suggested, some politically viable, others not, perhaps the most significant barrier to a cohesive approach to climate adaptation is the failure from the public and policy-makers to realize that different areas will be affected differently and that “one-size-fits-all” policy solutions will not be successful. In addition, as one area may identify and respond to challenges in their location, others should be supportive of those efforts, realizing that while such actions may be neither desirable nor appropriate for them, they may need support for solutions in the future in their areas. This project was designed as a framework to identify solutions and demonstrate differences between small regions and locales based on field conditions. The State of Florida was used as a case example to outline these differences because Florida is faced with significant challenges in the coming years related to water resources, the use of funds and political capital, and the potential for economic disruption. The intent is that the results of this project will lead to a series of recommendations and action steps for policy makers to conserve the state’s assets. A similar approach can be used in other states and countries to assess the likely policy and infrastructure needs for different locales. Water 2012-04-11 4 2 Article 10.3390/w4020367 367 388 2073-4441 2012-04-11 doi: 10.3390/w4020367 Frederick Bloetscher http://www.mdpi.com/2073-4441/4/2/345 Water is the primary medium through which climate change influences the Earth’s ecosystems and therefore people’s livelihoods and wellbeing. Besides climatic change, current demographic trends, economic development and related land use changes have direct impact on increasing demand for freshwater resources. Taken together, the net effect of these supply and demand changes is affecting the vulnerability of water resources. The concept of ‘vulnerability’ is not straightforward as there is no universally accepted approach for assessing vulnerability. In this study, we review the evolution of approaches to vulnerability assessment related to water resources. From the current practices, we identify research gaps, and approaches to overcome these gaps a generalized assessment framework is developed. A feasibility study is then presented in the context of the Lower Brahmaputra River Basin (LBRB). The results of the feasibility study identify the current main constraints (e.g., lack of institutional coordination) and opportunities (e.g., adaptation) of LBRB. The results of this study can be helpful for innovative research and management initiatives and the described framework can be widely used as a guideline for the vulnerability assessment of water resources systems, particularly in developing countries. Water 2012-04-10 4 2 Article 10.3390/w4020345 345 366 2073-4441 2012-04-10 doi: 10.3390/w4020345 Animesh K. Gain Carlo Giupponi Fabrice G. Renaud http://www.mdpi.com/2073-4441/4/2/321 The investigation of electric arc furnace (EAF) steel slag as a viable add-on technology to existing stormwater systems for the removal of dissolved phosphorus (P) was extended to explore the effects of varying environmental and treatment system conditions. Parameters such as stormwater composition, P concentration, metal concentration, pH, temperature, slag mass and slag particle size were varied. Observations relating to the method of P removal via EAF slag were also carefully considered to explain removal mechanisms involved. Results demonstrated that, although physisorption contributed to P reduction, it was not the key P removal mechanism. Instead, precipitation was observed to be a key removal pathway as evidenced by the correlation between the loss of iron (Fe) from slag and the amount of P removed from solution. The reduced removal of P by slag in a copper-dominant stormwater solution was attributed to the formation of a stable complex formed by the interaction of copper with the slag via the ion-exchange surface model. The stability of this complex inhibits the loss of Fe from the EAF slag and, consequently, P removal by means of precipitation. In terms of the effect of changing environmental and treatment system conditions on the P removal process, stormwater composition, P concentration, metal concentration, pH, temperature, slag mass and slag particle size were found to significantly influence the effectiveness of EAF slag in removing P from a given stormwater system. It was also established that a number of combinations of these factors influence P uptake differently. Water 2012-03-27 4 2 Article 10.3390/w4020321 321 344 2073-4441 2012-03-27 doi: 10.3390/w4020321 Nnaemeka C. Okochi Dena W. McMartin http://www.mdpi.com/2073-4441/4/2/295 The Dutch Delta Program is currently developing new government policies for flood protection and fresh water supply. Decision support instruments have to address the program’s technical and political complexity. The water system functions are highly interwoven and would benefit from an integrated approach on a national level, with decisions supported by a scientific Systems Analysis. Politically, there is a tendency towards broad participation and decentralization, and decision-making is typically supported by Conflict Resolution methods. To connect these two sides of the Delta Program’s task, an outline is presented of an internet community-based interactive instrument, preliminarily named SimDelta. On-line interactive maps and elements of serious gaming intuitively provide local Delta Program participants insight into the interaction between scenarios, problems, and solutions. SimDelta uses the internet to more frequently and efficiently present conceptual designs by architects and engineers to the Delta Program stakeholders, record their preferences, and “crowdsource” corrections, improvements and new ideas. Water 2012-03-23 4 2 Article 10.3390/w4020295 295 320 2073-4441 2012-03-23 doi: 10.3390/w4020295 Ties Rijcken Jan Stijnen Nadine Slootjes http://www.mdpi.com/2073-4441/4/2/283 In this work, the ability of a commercial spiral-wound nanofiltration membrane to remove hardness and ions from diluted seawater was studied. Experiments were carried out in the pressure range of 4–10 bar. Analyses of the samples, and permeates at different pressures, were performed and the effects of the trans-membrane pressure on the permeate flux were investigated. The results show that this nanofiltration membrane is capable of retaining 96–98% of the total hardness, 79–89% of the electrical conductivity and 79–89% of the total dissolved solid (TDS). Our results are in good agreement with those reported by the manufacturing company. Water 2012-03-23 4 2 Article 10.3390/w4020283 283 294 2073-4441 2012-03-23 doi: 10.3390/w4020283 Amir Abbas Izadpanah Asghar Javidnia http://www.mdpi.com/2073-4441/4/1/272 In recent years, disasters caused by flash floods with many casualties have occurred frequently in China. In order to effectively prevent flash flood disasters, the State Council approved the National Flash Flood Control Planning (NFFCP) in 2006. In this planning, non-structural measures are recommended as the first step to be adopted in the prevention of flash floods, debris flow and landslide disasters caused by heavy rainfall. In order to effectively build up a comprehensive non-structural measure system for flash flood disaster prevention, the Ministry of Water Resources has asked the local authorities to conduct studies in 103 pilot counties aiming to explore practical schemes. Based on the experience from these pilot counties, the construction of non-structural measures on flash flood disaster prevention for 1836 counties was officially initiated in 2010. The contents of non-structural measures for flash flood disaster prevention at county level include eight aspects. This paper will systematically illustrate the main contents of this national project for the construction of non-structural measures for flash flood disaster prevention in China. This work could provide a reference for other countries and regions in terms of flash flood prevention. Water 2012-03-19 4 1 Article 10.3390/w4010272 272 282 2073-4441 2012-03-19 doi: 10.3390/w4010272 Dongya Sun Dawei Zhang Xiaotao Cheng http://www.mdpi.com/2073-4441/4/1/260 The objective of this study was to investigate the application of constructed wetlands as a mean to manage olive mill wastewater (OMW). Two free water surface (FWS) constructed wetlands, one without (CW1) and one with effluent recirculation (CW2), were operated for a two-year period with diluted OMW (1:10) and evaluated in terms of the removal of COD, TSS, TKN, NH4+-N, NO3−-N, TP and total phenols. The organic loading rate of CWs was adjusted to 925 kg BOD/ha·d. In CW1 the removal efficiency averaged 80%, 83%, 78%, 80%, and 74% for COD, TSS, TKN, TP, and total phenols, respectively, during the operation period. Effluent recirculation further improved the treatment efficiency which approached 90%, 98%, 87%, 85%, and 87% for COD, TSS, TKN, TP, and total phenols, respectively. Constructed wetlands also showed high removal efficiency for NH4+-N. Nitrate concentration maintained low in both CWs basins, probably due to the prevalence of high denitrification rates that efficiently removed the NO3--N produced by NH4+-N oxidation. Despite the increased removal percentages, pollutant concentration in effluent exceeded the allowable limits for discharge in water bodies, suggesting that additional practices, including enhanced pre-application treatment and/or higher dilution rates, are required to make this practice effective for OMW management. Water 2012-03-12 4 1 Article 10.3390/w4010260 260 271 2073-4441 2012-03-12 doi: 10.3390/w4010260 Iosif E. Kapellakis Nikolaos V. Paranychianakis Konstantinos P. Tsagarakis Andreas N. Angelakis http://www.mdpi.com/2073-4441/4/1/237 Recent coastal storms in southern Africa have highlighted the need for more proactive management of the coastline. Within the southern and eastern African region the availability of coastal information is poor. The greatest gap in information is the likely effects of a combination of severe sea storms and future sea level rise (SLR) on the shoreline. This lack of information creates a barrier to informed decision making. This research outlines a practical localized approach to this problem, which can be applied as a first order assessment within the region. In so doing it provides a cost effective and simple decision support tool for the built environment and disaster professionals in development and disaster assessments. In a South African context the newly promulgated Integrated Coastal Management Act requires that all proposed coastal developments take into consideration future SLR, however such information currently does not exist, despite it being vital for informed planning in the coastal zone. This practical approach has been applied to the coastline of Durban, South Africa as a case study. The outputs are presented in a Geographic Information System (GIS) based freeware viewer tool enabling ease of access to both professionals and laypersons. This demonstrates that a simple approach can provide valuable information about the current and future risk of flooding and coastal erosion under climate change to buildings, infrastructure as well as natural features along the coast. Water 2012-03-05 4 1 Article 10.3390/w4010237 237 259 2073-4441 2012-03-05 doi: 10.3390/w4010237 Andrew A. Mather Derek D. Stretch http://www.mdpi.com/2073-4441/4/1/219 Extra treatment stages are required to polish the secondary effluent for unrestricted reuse, primarily for agricultural irrigation. Improved technology for the removal of particles, turbidity, bacteria and cysts, without the use of disinfectants is based on MicroFiltration (MF) and UltraFiltration (UF) membrane technology and in series with Reverse Osmosis (RO) for dissolved solids removal. Field experiments were conducted using a mobile UF and RO membrane pilot unit at a capacity of around 1.0 m3/hr. A management model was defined and tested towards optimal polishing of secondary effluent. The two major purposes of the management model are: (i) to delineate a methodology for economic assessment of optimal membrane technology implementation for secondary effluent upgrading for unrestricted use, and; (ii) to provide guidelines for optimal RO membrane selection in regards to the pretreatment stage. The defined linear model takes into account the costs of the feed secondary effluent, the UF pretreatment and the RO process. Technological constraints refer primarily to the longevity of the membrane and their performance. Final treatment cost (the objective function) includes investment, operation and maintenance expenses, UF pretreatment, RO treatment, post treatment and incentive for low salinity permeate use. The cost range of water for irrigation according to the model is between 15 and 42 US cents per m3. Water 2012-03-05 4 1 Article 10.3390/w4010219 219 236 2073-4441 2012-03-05 doi: 10.3390/w4010219 Amos Bick Leonid Gillerman Yossi Manor Gideon Oron http://www.mdpi.com/2073-4441/4/1/196 The impacts of flood events that occurred in autumn 2011 in the Italian regions of Liguria and Tuscany revived the engagement of the public decision-maker to enhance the synergy of flood control and land use planning. In this context, the design of efficient flood risk mitigation strategies and their subsequent implementation critically relies on a careful vulnerability analysis of the fixed and mobile elements exposed to flood hazard. In this paper we develop computation schemes enabling dynamic vulnerability and risk analyses for a broad typological variety of elements at risk. To show their applicability, a series of prime examples are discussed in detail, e.g. a bridge deck impacted by the flood and a car, first displaced and subsequently exposed to collision with fixed objects. We hold the view that it is essential that the derivation of the computational schemes to assess the vulnerability of endangered objects should be based on classical and fluid mechanics. In such a way, we aim to complement from a methodological perspective the existing, mainly empirical, vulnerability and risk assessment approaches and to support the design of effective flood risk mitigation strategies by defusing the main criticalities within the systems prone to flood risk. Water 2012-02-28 4 1 Article 10.3390/w4010196 196 218 2073-4441 2012-02-28 doi: 10.3390/w4010196 Bruno Mazzorana Laura Levaggi Omar Formaggioni Claudio Volcan http://www.mdpi.com/2073-4441/4/1/170 Changes in the seasonal cycle of mean sea level (MSL) may affect the heights of storm surges and thereby flood risk in coastal areas. This study investigates the intra- and inter-annual variability of monthly MSL and its link to the North Atlantic Oscillation using records from 13 tide gauges located in the German Bight. The amplitudes of the seasonal MSL cycle are not regionally uniform and vary between 20 and 29 cm. Generally, the amplitudes are smaller at the southwestern stations, increasing as one travels to the northeastern part. The amplitudes, as well as the phase of the seasonal cycle, are characterized by a large inter-annual and inter-decadal variability, but no long-term trend could be detected. Nevertheless, in the last two decades annual maximum peaks more frequently occurred in January and February, whereas beforehand an accumulation was detected for the November and December period. These changes in phase in the various sea level time series are consistent with a shift in the annual cycle, which is, however, not significant. The changes are associated with strongly increasing trends in monthly MSL of the winter season (J–M), which are considerably higher compared to the remaining seasons. For the same season, the MSL and North Atlantic Oscillation (NAO) indices show strong similarities, resulting in statistically significant correlations (r ~ 0.7). Hence, these changes are linked with changing pressure conditions over the North Atlantic, which lead to a strong phase of positive values in the NAO index between the 1960’s and 1990’s. Water 2012-02-24 4 1 Article 10.3390/w4010170 170 195 2073-4441 2012-02-24 doi: 10.3390/w4010170 Sönke Dangendorf Thomas Wahl Hartmut Hein Jürgen Jensen Stephan Mai Christoph Mudersbach http://www.mdpi.com/2073-4441/4/1/157 California’s development and success have been shaped by its ability to manage floods. This management has varied over the history of California’s economic and political development and continues in various forms today. California will always have flood problems. A range of options are available to aid in flood management problems and have been used over time. These options can be contrasted with flood management elsewhere and the types of options used to manage other types of hazards in California, such as earthquakes, wildfires, and droughts. In the future, flood management in California will require greater reliance on local funding and leadership, reflecting diminished federal and state funding, with more effective state and federal guidance. Effective flood management will also tend to integrate flood management with actions to achieve environmental and other water supply objectives, both to gain revenues from a broader range of beneficiaries as well as to make more efficient use of land and water in a state where both are often scarce. Water 2012-02-14 4 1 Article 10.3390/w4010157 157 169 2073-4441 2012-02-14 doi: 10.3390/w4010157 Jay R. Lund http://www.mdpi.com/2073-4441/4/1/135 The European Directive on the Assessment and Management of Flood Risks is likely to cause changes to flood policy in Germany and other member states. With its risk governance approach, it introduces a holistic and catchment-oriented flood risk management and tries to overcome shortcomings of the past, such as the event-driven construction of mainly structural measures. However, there is leeway for interpretation in implementing the directive. The present paper gives an overview on the implementation of the floods directive in Germany and is divided into two qualitative empirical case studies. Case Study I investigates the level of acceptance of the floods directive among decision-makers in the German part of the Rhine river basin. Findings show that the federal states respond differently to the impulse given by the floods directive. Whereas some decision-makers opt for a pro-forma implementation, others take it as a starting point to systematically improve their flood policy. Case Study II presents recommendations for a successful implementation of flood risk management plans that have been developed within a project for the water authority in Bavaria and might be interesting for other federal/member states. For a participation of the interested parties on the level of shared decision-making, the planning process has to work on sub-management-plan level (15–20 communities). The water resources authority has to adopt a multi-faceted role (expert, responsible or interested party depending on the discussed topics). Water 2012-02-02 4 1 Article 10.3390/w4010135 135 156 2073-4441 2012-02-02 doi: 10.3390/w4010135 Marc Daniel Heintz Maria Hagemeier-Klose Klaus Wagner http://www.mdpi.com/2073-4441/4/1/123 The rapid urbanization facing developing countries is increasing pressure on public institutions to provide adequate supplies of clean water to populations. In most developing countries, the general public is not involved in strategies and policies regarding enhancement, conservation, and management of water supply systems. To assist governments and decision makers in providing potable water to meet the increasing demand due to the rapid urbanization, this study sought to characterize existing water supply systems and obtain public opinion for identifying a community water supply system model for households in a residential neighborhood in Lomé, Togo. Existing water supply systems in the study area consist of bucket-drawn water wells, mini water tower systems, rainwater harvesting, and public piped water. Daily domestic water consumption in the study area compared well with findings on water uses per capita from Sub-Saharan Africa, but was well below daily water usage in developed nations. Based on the surveys, participants thought highly of a large scale community water tower and expressed interest in maintaining it. Even though people rely on water sources deemed convenient for drinking, they also reported limited confidence in the quality of these sources. Water 2012-02-01 4 1 Article 10.3390/w4010123 123 134 2073-4441 2012-02-01 doi: 10.3390/w4010123 Laurent Ahiablame Bernard Engel Taisha Venort http://www.mdpi.com/2073-4441/4/1/107 Urban water reuse is one of the most rapidly growing water reuse applications worldwide and one of the major elements of the sustainable management of urban water cycle. Because of the high probability of direct contact between consumers and recycled water, many technical and regulatory challenges have to be overcome in order to minimize health risks at affordable cost. This paper illustrates the keys to success of one of the first urban water reuse projects in the island Bora Bora, French Polynesia. Special emphasis is given on the reliability of operation of the membrane tertiary treatment, economic viability in terms of pricing of recycled water and operating costs, as well as on the benefits of water reuse for the sustainable development of tourist areas. Water 2012-01-31 4 1 Article 10.3390/w4010107 107 122 2073-4441 2012-01-31 doi: 10.3390/w4010107 Valentina Lazarova Vincent Sturny Gaston Tong Sang http://www.mdpi.com/2073-4441/4/1/85 The State of Iowa, located in the Midwestern United States, has experienced an increased frequency of large floods in recent decades. After extreme flooding in the summer of 2008, the Iowa Flood Center (IFC) was established for advanced research and education specifically related to floods. IFC seeks to improve Iowa’s flood hazard awareness through the development of easily accessible, high-quality mapping products. Mapping initiatives consist of two model development approaches: (1) statewide floodplain delineation using one-dimensional (1D) models, and (2) urban flood mapping using detailed one-dimensional/two-dimensional (2D) coupled models. The statewide floodplain project will benefit Iowans through the creation of a comprehensive set of floodplain maps developed under a single consistent methodology. These will be important tools in evaluating flood risk, regulating floodplains, and participating in the National Flood Insurance Program. Detailed urban flood analyses are used to develop inundation map libraries. These map libraries are meant to supplement National Weather Service river stage flood forecasts by providing a visual representation of potential flood extent according to predicted river stage at stream gage locations. Water 2012-01-16 4 1 Article 10.3390/w4010085 85 106 2073-4441 2012-01-16 doi: 10.3390/w4010085 Daniel Gilles Nathan Young Harvest Schroeder Jesse Piotrowski Yi-Jia Chang http://www.mdpi.com/2073-4441/4/1/63 This paper analyzes the effects of climate change on water availability and use in the Limpopo River Basin of Southern Africa, using a linked modeling system consisting of a semi-distributed global hydrological model and the Water Simulation Module (WSM) of the International Model for Policy Analysis of Agricultural Commodities and Trade (IMPACT). Although the WSM simulates all major water use sectors, the focus of this study is to evaluate the implications of climate change on irrigation water supply in the catchments of the Limpopo River Basin within the four riparian countries: Botswana, Mozambique, South Africa, and Zimbabwe. The analysis found that water resources of the Limpopo River Basin are already stressed under today’s climate conditions. Projected water infrastructure and management interventions are expected to improve the situation by 2050 if current climate conditions continue into the future. However, under the climate change scenarios studied here, water supply availability is expected to worsen considerably by 2050. Assessing hydrological impacts of climate change is crucial given that expansion of irrigated areas has been postulated as a key adaptation strategy for Sub-Saharan Africa. Such expansion will need to take into account future changes in water availability in African river basins. Water 2012-01-16 4 1 Article 10.3390/w4010063 63 84 2073-4441 2012-01-16 doi: 10.3390/w4010063 Tingju Zhu Claudia Ringler http://www.mdpi.com/2073-4441/4/1/45 This paper presents the basic principles for the integration of the water and carbon footprints cost into the resource and environmental costs respectively, taking the suggestions set by the Water Framework Directive (WFD) 2000/60/EC one step forward. WFD states that full water cost recovery (FWCR) should be based on the estimation of the three sub-costs related: direct; environmental; and resource cost. It also strongly suggests the EU Member States develop and apply effective water pricing policies to achieve FWCR. These policies must be socially just to avoid any social injustice phenomena. This is a very delicate task to handle, especially within the fragile economic conditions that the EU is facing today. Water losses play a crucial role for the FWC estimation. Water losses should not be neglected since they are one of the major “water uses” in any water supply network. A methodology is suggested to reduce water losses and the related Non Revenue Water (NRW) index. An Expert Decision Support System is proposed to assess the FWC incorporating the Water and Carbon Footprint costs. Water 2012-01-16 4 1 Article 10.3390/w4010045 45 62 2073-4441 2012-01-16 doi: 10.3390/w4010045 Vasilis Kanakoudis Stavroula Tsitsifli Anastasia Papadopoulou