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Industrial water supply networks can use multiple water resources (i.e., municipal water, surface water, municipal treated wastewater, groundwater, and seawater) with their respective pre-treatment technologies to meet the industrial water demand. The water quality of each water resource varies, and the associated pre-treatment technologies provide different technical and economic efficiencies that directly impact the overall cost of the water supply network. This paper proposed a superstructure-based mathematical modeling optimization to design the multi-resources industrial water supply network with optimal pre-treatment technologies. The established model includes the relative equations among different pre-treatment units and water sinks, flow rate constraints, property constraints, logic constraints, and cost constraints. These constraints are used to describe water treatment technologies selection through general disjunctive programming (GDP) and transform them into a mixed-integer nonlinear programming (MINLP) model for the problem solution. The minimum annualized cost of the water supply network is taken as an objective function. The optimization and comparison analysis of the coastal oil refinery water supply system is illustrated. The results show that an integrated water supply network of surface water and municipal treated wastewater has the lowest annualized cost of 12.3 million CNY/y. The cost is reduced by 7.44 million CNY/y compared to municipal water as the single water resource. This integrated water supply network saves freshwater resources, provides substantial economic gains, and encourages municipal treated wastewater reuse. • Industrial water supply network with multiple water resources is proposed. • General disjunctive programming is used for optimal selection of pretreatment techniques. • Total annualized cost reduction is achieved for coastal oil refinery. • Sustainable water supply system with non-conventional water resources is developed. [ABSTRACT FROM AUTHOR]

Climate change and socioeconomic factors have increased the complexity of urban water supply systems. Thus, fresh water sources are being gradually diversified to improve the reliability and resilience of the systems. However, as the number of source blending options grows, optimization tools are needed to design drinking water supply systems that comply with indicators of cost, resilience, and water quality. This paper proposes a pioneering methodological approach, based on an ant-colony-optimization (ACO) algorithm, to optimize the blending of drinking water from different sources to minimize operational costs of a given system originating from a number of impaired water sources while complying with water quality standards. To evidence the potential of the ACO algorithm to solve such a system, a virtual case study was designed that considers eight fresh water sources, including seawater desalination and potable reuse. Seven scenarios were developed with different weightings to service outage, water conveyance and treatment costs while complying with water quality goals in regard to total organic carbon, nitrates, and total dissolved solids. It was shown that the cost per volumetric unit of water can vary considerably depending on the weightings of the three cost items. This paper provides a rigorous scientific approach to propose a methodology supporting the decision-making process of selecting a mixture of different sources to achieve the overall lowest system cost. Hence, this work contributes to improving the resilience and sustainability of urban water supplies. [ABSTRACT FROM AUTHOR]

In the context of the ongoing worldwide efforts directed to achieving environmental sustainability by mitigating environmental challenges and reversing the depletion of the environmental resources, the work presented in this paper has the purpose to identify the most effective solution for ensuring access to good quality drinking water for the localities in the southern part of Constanta County, Romania. At present, the communities in the analyzed area are using drinking water abstracted from ground water sources which have registered continuous quality degradation over the last 30 years, while the water losses in the water supply systems are high. As the existing water treatment facilities are unable to remove the pollutants found in the raw water (ammonia, nitrates, Iron and Manganese), within a complex regional project which aims at the same time for reduction of water losses and reaching drinking water quality compliance, a comprehensive analysis was prepared, in order to identify the most efficient solution for supplying the localities at the border of the Black Sea with sufficient and appropriate quality water. This paper shows the systematic approach used for conducting the options analysis in which there have been considered different applicable solutions ranging from decommissioning the existing sources and construction of a regional water supply local treatment, to keeping the existing sources and construction of new appropriate treatment facilities or blending water from multiple sources. The conducted analysis has revealed that the most feasible option for long term sustainability of water supply is the construction of a regional water supply system supplied by a very good quality wellfield with additional flow input from an existing water treatment plant having spare capacity available. [ABSTRACT FROM AUTHOR]

In federations such as the United States, governments at various levels are experimenting with new watershed governance arrangements to protect water quality for both ecosystem health and human consumption. Such arrangements may bring previously uncooperative governments together to credibly commit to resource protection under the auspices of new and intricate formal institutions. Given the risks of cooperation, theory indicates that a robust arrangement will contain means of holding governing actors accountable to each other. This paper examines a purportedly successful case, the New York City watershed governance arrangement, to identify how safeguards against intergovernmental opportunism promote lasting cooperation. Using the qualitative method of process tracing, this paper finds that the New York City watershed governance arrangement uses structural, judicial, and popular safeguards against opportunistic behaviors by governing actors that might threaten the resource or the arrangement. The results indicate that such safeguards are present and interact with other safeguards and rule institutions at the state and federal level to maintain compliance. [ABSTRACT FROM AUTHOR]

Water supply must take into consideration a variety of factors, including consumer habits, options and needs. Little is known about water demands in rural areas of developing regions. Based on data from southern Mali, this paper banks on the hypothesis that water consumption in rural villages can be predicted by combining measurable variables with spatial analyses. A ten-day field campaign was carried out at the end of the dry season 2016. All improved water sources were checked for functionality, flow rate and water quality. Outcomes were coupled with those from over one-hundred household interviews and incorporated into a geographic database. Buffered network analyses were used to quantify the main spatial determinants for water use. Simple and multiple regression models were then developed to establish the main predictors for per capita and household water consumption. Multiple regression reveals that models based on the number of household members, travel time and total travel distance provide robust forecasts for water consumption (R 2 > 0.93). Conversely, potentially relevant parameters such as affordability or water quality were not statistically significant. This could be attributed to the presence of free water sources and to the absence of quality-monitoring, respectively. Outcomes also suggest that having access to basic means of transportation, such as pushcarts, doubles water consumption at the household level. In terms of access to improved water sources, coverage was found to be lower in practice than on paper. These outcomes contribute to the growing body of literature that challenges the widely accepted assumption that 90% of the world population has access to safe drinking supplies. [ABSTRACT FROM AUTHOR]

Water distribution Networks (WDNs) are one of the most important infrastructures for modern society. Due to accidental or malicious reasons, water contamination incidents have been repeatedly reported all over the world, which not only disrupt the water supply but also endanger public health. To ensure the safety of WDNs, water quality sensors are deployed across the WDNs for real-time contamination detection and source identification. In the literature, various methods have been employed to improve the performance of contamination source identification (CSI) and recent studies show that there is a great potential to tackle the CSI problem by deep learning models. The success of deep learning based CSI methods often requires a large size of training samples being collected. In real-world situations, the number of contamination events occurring in a single WDN is rather small, especially for a newly built WDN. However, the existing CSI methods in the literature mostly focus on the study of training and applying models on the same WDNs and the knowledge of CSI gained from one WDN cannot be reused by a different WDN. To these ends, based on the application of graph convolutional networks, this paper provides a solution for cross-network CSI that can transfer the CSI knowledge learned from one WDN to a different WDN. Empirically, based on a benchmark WDN in the task of contamination source identification, we show that the proposed cross-network CSI method can achieve comparable accuracy even trained on a different WDN. [ABSTRACT FROM AUTHOR]

Eutrophication is one of the most pressing problems affecting water quality. As a consequence, harmful algae blooms (HABs) are intensifying their occurrence in many aquatic ecosystems around the world. Under this water quality risk scenario, long term monitoring arises as a need to recognize, understand and anticipate the HABs outbreaks. However, existing monitoring methodologies are limited when dealing with HABs, thus forcing to make assumptions and decisions based on interpolated and inconsistent data. This conceptual paper attempts to highlight the importance of moving towards an integrated water monitoring methodology, where manual sampling, on-site automatic high-frequency monitoring (AHFM) and remote sensing are aligned to facilitates decision-making. In addition, because of the key role of microbial communities on the drift of aquatic ecosystems and water quality, they should be considered as a key element in HABs monitoring and management programs. In this manner, the biotic knowledge could be integrated into coordinated response plans as ecosystem management tools. Therefore, this holistic approach could provide decision makers and stakeholders an adaptive water resource management grounded on the theory of ecohydrology. [ABSTRACT FROM AUTHOR]

Intelligent prediction of water quality plays a pivotal role in water pollution control, water resource protection, emergency decision-making for sudden water pollution incidents, tracking and evaluation of water quality changes in river basins, and is crucial to ensuring water security. The primary methodology employed in this paper for water quality prediction is as follows: (1) utilizing the comprehensive pollution index method and Mann-Kendall (MK) trend analysis method, an assessment is made of the pollution status and change trend within the basin, while simultaneously extracting the principal water quality parameters based on their respective pollution share rates; (2) employing the spearman method, an analysis is conducted to identify the influential factors impacting each key parameter; (3) subsequently, a water quality parameter prediction model, based on Long Short-Term Memory (LSTM) analysis, is constructed using the aforementioned driving factor analysis outcomes. The developed LSTM model in this study showed good prediction performance. The average coefficient of determination (R2) of the prediction of crucial water quality parameters such as total nitrogen (TN) and dissolved oxygen (DO) reached 0.82 and 0.86 respectively. Additionally, the error analysis of WQI prediction results showed that >75% of the prediction errors were in the range of 0–0.15. The comparative analysis revealed that the LSTM model outperforms both the random forest (RF) model in time series prediction and demonstrates superior robustness and applicability compared to the AutoRegressive Moving Average with eXogenous inputs model (ARMAX). Hence, the model developed in this study offers valuable technical assistance for water quality prediction and early warning systems, particularly in economically disadvantaged regions with limited monitoring capabilities. This contribution facilitates resource optimization and promotes sustainable development. • Developed a multivariate water quality prediction model with some interpretability based on LSTM network. • There was a strong nonlinear relationship between climate change factors and several water quality parameters. • Strong R2 scores (0.82, 0.86, and 0.79) were achieved for TN, DO, and WQI prediction. • The prediction model showed high potential in future water environment monitoring and supervision. [ABSTRACT FROM AUTHOR]

Desalinated seawater often represents lack of merit nutrients, unstable and low buffer capacity owing to the fact that various aqueous ions are almost removed. The various re-mineralization processes, such as blending with surface water, chemicals dosing, and minerals dissolution, are commonly used for introduction of merit ions and carbonate alkalinity to desalinated seawater to meet health requirement and to protect water supply facilities from corrosion. This paper discusses the optimization of various re-mineralization processes based on accurate model computation with emphasis on carbonate system model, water stability index, blending model, and mineral surface dissolution model. The accurate model computation investigation justifies the efforts and costs through various re-mineralization processes for achieving narrow water quality criteria. • Proposing approach to map re-mineralization strategies of desalinated seawater meeting with narrow water quality criteria. • Proposing differential algebraic system coupled with re-mineralizations, aqueous ion equilibrium, water quality indicators.. • Blending desalinated seawater is limited by the water quality and source of surface water. • Adding Ca(OH) 2 slowly into desalinated seawater pre-dissolved by CO 2 weaken turbidity generated by scaling particles. • Limestone dissolution and Ca(OH) 2 +CO 2 dosing represent relatively techno-economical. [ABSTRACT FROM AUTHOR]

• Scaling of water supply pipelines deteriorates operation and water quality safety. • The calcite- and aragonite-based scale is doped with heavy metals and microorganisms. • MD, DFI and EIS are new methods to study scale. • Higher carbonate hardness in water is the key factor leading to pipe scaling. • A scale prediction framework based on P.S.I and EIS should be established. The scaling problem in the water supply pipeline will increase the resistance coefficient of the pipeline and the pressure of the water supply pipeline, which will not only affect the operation safety of the water supply pipeline, but also cause energy waste. The scale in the pipeline will also enrich heavy metal ions and pathogenic microorganisms, affecting the safety of water supply water quality and causing secondary pollution of water quality. At present, a lot of research has been done on the composition structure and crystallization process of the scale. The study found that calcite is the main component of the scale; the scale process is a heterogeneous nucleation process induced by heavy metal particles and their corrosion products in the pipeline. The introduction of electrochemical detection technology, density functional theory and molecular dynamics simulation has greatly improved the accuracy and timeliness of water scaling conditions detection and realized the visualization of scaling mechanism. In this paper, the measurement methods of the scale in the water supply pipeline and the corresponding material composition and crystal structure characteristics are reviewed, and the mechanism of the scale and the water quality conditions are summarized. At the end of this paper, based on summarizing the existing water quality scaling tendency evaluation methods, it is proposed to establish a water quality potential scaling risk assessment framework based on Puckorius scaling index (PSI) and electrochemical impedance spectroscopy (EIS) in the future. [Display omitted] [ABSTRACT FROM AUTHOR]

China has been facing increasingly severe water scarcity that seriously threatens the socio-economic development and its sustainability of this country. This paper is intended to analyze and assess the water security of China. It first attempts to characterize the current status of water security within a risk-based, integrated framework that encompasses five key aspects critical to water sustainability, including water availability, water use patterns, wastewater generation and pollution control, water institutions and management, and health of aquatic systems and societal vulnerability. Based on the above assessment, the paper then analyzes emerging challenges for water security brought by climate change, population growth and rapid urbanization, and the water-food-energy nexus. In the end, the paper discusses China's future prospects on water security, including current achievements, government actions and policy initiatives, and recommendations for management improvement aimed at increasing water security. [ABSTRACT FROM AUTHOR]

Modern urban societies depend greatly on critical lifeline systems such as drinking water supply. Water supply systems in the United States comprise about one million mile length of interconnected pipelines that transport water from sources to consumption points with the support of treatment plants, pumping stations, storage tanks and valves. While depleting freshwater sources in some regions is an alarming concern, supply infrastructure woes exacerbate the problem of meeting supply reliability targets. Evidenced by the “D” or lower grade it has been receiving over the past few ASCE infrastructure report cards, the quality of water supply infrastructure has degraded to an extent where 240,000 water mains fail annually in the U.S. A majority of these failures result in significant economic, environmental and societal consequences. Pro-active rehabilitation of deteriorated infrastructure will avoid these unwarranted failure consequences. This paper employs empirical analysis of the economic, environmental and societal consequences of large-diameter water main failures to estimate their overall impact cost. Data on the impacts of 11 large-diameter water main failures has been gathered and synthesized. The results of this paper will aid in predicting the future water main failure consequences to enable risk-based, long-term capital improvement planning of water supply systems. [ABSTRACT FROM AUTHOR]

Springs are environmental objects of unique character, determined by water resources and high water quality, important for economic, recreational, landscape, and cultural aspects. Springs, on the boundary of surface and groundwater resources, are fundamental for understanding resources and circulation of water in the river catchment, and can be good indicators for assessment of the natural environment changes. The paper presents results of discharge measurements analyses for 65 springs performed in the period 1946-2016 in the area of the Lublin Upland and Roztocze in Poland. Based on approximately 5,000 measurements, characteristic discharges were determined for each spring: minimum, mean, and maximum, as well as the variation coefficient. The role of spring waters in the alimentation of rivers was assessed. The most abundant springs (continuously or periodically exceed 100 dm3 · s–1, maximum discharge 400 dm3 · s–1) are alimented from the Cretaceous aquifer. The springs show high discharge stability in the multiannual rhythm and seasonal regime of water resource fluctuations resulting from the appearance of a series of years with increased or reduced atmospheric precipitation. Variable response to atmospheric alimentation results from the conditions of water flow through the aeration zone. Springs provide from 40% to almost 100% of river water. Because of economic activity, contributing to the transformation of environmental components and constituting a threat to springs, their niches, and water quality, there is the need for their protection and their preservation in a possibly natural state in accordance with the local environmental conditions. [ABSTRACT FROM AUTHOR]

Floods are one of the deadliest natural hazards and are exacerbated by changes in land-use and climate. Urban development decreases infiltration by reducing pervious areas and increases the accumulation of pollutants during dry weather. It also decreases infiltration by reducing pervious areas and increases the accumulation of pollutants during dry periods. During rainy events, there is an increase in pollution concentrations and runoff that may be a source of water supply during drought periods. Modeling the quantity and quality dynamics of stormwater runoff requires a coupled hydrodynamic module capable of estimating the transport and fate of pollutants. In this paper, we evaluate the applicability of a distributed hydrodynamic model coupled with a water quality model (HydroPol2D). First, the model is compared to GSSHA and WCA2D in the V-Tilted catchment, and the limitation of the critical velocity of WCA2D is investigated. We also applied the model in a laboratory wooden board catchment, focusing on the validation of the numerical approach to simulate water quality dynamics. Then, we apply HydroPol2D in the Tijuco Preto catchment, in São Carlos - Brazil, and compare the modeled results with the full momentum solver of the HEC-RAS 2D. This catchment shares similar characteristics with many poorly-gauged and human-impacted catchments worldwide. The implementation of the model, the governing equations, and the estimation of input data are discussed, indicating the challenges and opportunities to scale HydroPol2D into the reality of data scarcity of larger poorly-gauged catchments. For a 1-yr return period of rainfall and antecedent dry days, and assuming an uncertainty of 40% in the water quality parameters, the results indicate that the maximum concentration of total suspended solids (TSS), the maximum load and the mass of the pollutant washed in 30% of the volume are, 456 ± 260 mgL-1km-2, 2. 56 ± 0. 4 kgs-1km-2, and 89 % ± 10 % , respectively. [Display omitted] • A new coupled hydrodynamic and water quality 2D model is developed (HydroPol2D). • The spatial–temporal dynamics of Total Suspended Solids (TSS) is investigated. • We estimate TSS transport rates and first flush for a 1-year return period. • The maximum TSS load is 2. 56 ± 0. 4 kg s − 1 km − 2 for a 40% uncertainty in water quality parameters. • HydroPol2D can also be used for flood inundation mapping, infiltration, and evapotranspiration modeling. [ABSTRACT FROM AUTHOR]

Water is the source of life and the link that binds all living beings on this planet. This paper takes the Minhang District of Shanghai as an example to analyze the residual chlorine and turbidity of the secondary water supply detected by the six monitoring points in the area. The influence factors of water quality are analyzed according to the test results, at the same time, the correlation between turbidity and residual chlorine is explored, and corresponding solutions are proposed to provide reference for solving these problems. [ABSTRACT FROM AUTHOR]

Secondary water supply, as the final component of the urban water supply system, is critical for ensuring the safety of urban water supply, and is directly related to customers' water use. However, water stored in secondary water supply facilities will more likely to lose disinfectants (chlorine residual) which can lead to bacterial regrowth and water quality deterioration. Therefore, it is important to solve problems associated with secondary water supply and manage the system more effectively. In the context of the Internet of Things, the intelligent management model based on information technology has become the growing trend. This paper introduces the application of the secondary water supply intelligent management model in Shanghai. [ABSTRACT FROM AUTHOR]

Abstract A river basin usually provides water for multiagent. Imperfect coordination mechanisms among these agents, however, usually lead to serious water shortage, pollution, and ecological degradation. Therefore, it is vital to conduct research on allocating different kinds of water resources among multiagent including the water quantity agent, water quality agent and environment agent within a river basin. This paper proposes an optimization-simulation method that takes into consideration engineering measures, including water transfer projects, reservoirs, canal heads, and pump stations; multi-water resources such as local surface water, transferred water, groundwater, and reused sewage; and multiagent for remitting serious water problems. In the proposed optimization-simulation method, the groundwater and reused sewage are first allocated according to the water resources allocation simulation module (Module 1). Then, local surface and transferred water are allocated based on the water resources allocation optimization module (Module 2), which comprises water quantity, water quality and environment agents' objectives based on synergism. Finally, the instream water quality is simulated according to the water quality simulation module (Module 3). Results show that, compared to the current situation, the water quantity and environment agent guarantee rates can satisfy the design requirements in the planning year of 2020. The regulated instream water quality is also improved; although, it still remains relatively poor. Water quality in the downstream is worse than that in the upstream. In addition, the water quality shows a positive correlation with the instream streamflow. These results certify the proposed optimization-simulation method can provide support for efficacious multiagent water resources allocation. Highlights • A coupled quantity-quality-environment water allocation model is constructed. • Multi-water resources, many types of engineering projects and multiagent are considered. • Multi-water resources cover local surface, transferred water, groundwater, and reused sewage. • Water transfer projects, reservoirs, canal heads, and pump stations are selected projects. • Coupled model is solved by an optimization-simulation method. [ABSTRACT FROM AUTHOR]

In accordance with national policies, the Jiansanjiang Administration of Heilongjiang Province in China has assumed a heavy task of grain production in recent years. The spatial matching status of water and land resources is a prerequisite for grain production. To analyze the potential for grain production objectively, the matching characteristics of agricultural water resources and land resources in Jiansanjiang Administration were analyzed for this paper. The spatial distribution pattern of the water and land resources was analyzed, and the amount of broadly-defined agricultural water resources (BAWR) and cultivated area were introduced as the water resource and land resource quantity parameters, respectively. The Gini coefficient model for agricultural water and land resource matching and the model for measuring the matching index between the BAWR and land resources (MIBAWRLR) were then constructed to evaluate the degree of matching between agricultural water and land resources in Jiansanjiang Administration and 15 farms in the region. Based on the Cobb-Douglas all-factor production function, the input–output model of agricultural production was built, with the grain yield per hectare used as the explained variable and basic, technological, and natural factors as the explaining variables. The results are as follows: ① The results of the MIBAWRLR indicate that the matching situation between agricultural water resources and land resources in Jiansanjiang Administration has improved, which was consistent with the results of the Gini coefficient model. The matching situation on the farms of Jiansanjiang Administration worsened from south to north, and the spatial matching pattern was consistent with the spatial distribution of the proportion between blue water and green water at each farm, i.e., the matching situation on a farm with a high proportion of blue water was satisfactory. ② According to the input–output model of agricultural production, introducing the BAWR into the established models as the characteristic parameter of water resource quantity is scientific and reasonable. [ABSTRACT FROM AUTHOR]

• This study combines water quality, land use and environmental data to examine their impact on water quality in rural areas across space and time. • This analysis shows that the land uses with the largest negative impacts on water quality are septic tanks and nutrient loads from agriculture. • The coefficient on organic N falls significantly between 2002–2011 as the environmental production function of agriculture increased efficient. • Solutions will depend on a multi-sectoral approach aimed at addressing the human and land-use factors affecting water quality. • The analytical framework provides a tool in the management of risk, allowing for more appropriate land use to restore and maintain water quality. This paper, using Ireland as a case study, examines the relationship between rural economic activities and river water quality. The stipulation from the EU water framework directive (WFD) that all surface waters in the EU must be of 'good ecological status' necessitates a quantitative understanding of the major determinants of water quality. Within this context, this paper combines a number of spatial datasets relating to agricultural, land use, residential and industrial activities, to examine the major economic influences on the ecological quality of water resources. It is hoped that providing a comprehensive understanding of the effect of a variety of economic activities that influence the ecological quality of water will be an important tool in the management of risk and will allow for more appropriate land use planning aimed at restoring and maintaining water quality as required by the WFD. Results indicate that the level of forestry, industrial activity, the intensity and type of agricultural activity and the type of wastewater treatment in an area are all critical factors affecting the quality of water resources. The model finds that relationship between agriculture and water quality improved over time during a period where there was substantial legislative measures and financial support to facilitate improved water quality. [ABSTRACT FROM AUTHOR]

Degradation of freshwater ecosystems and the services they provide is a primary cause of increasing water insecurity, raising the need for integrated solutions to freshwater management. While methods for characterizing the multi-faceted challenges of managing freshwater ecosystems abound, they tend to emphasize either social or ecological dimensions and fall short of being truly integrative. This paper suggests that management for sustainability of freshwater systems needs to consider the linkages between human water uses, freshwater ecosystems and governance. We present a conceptualization of freshwater resources as part of an integrated social-ecological system and propose a set of corresponding indicators to monitor freshwater ecosystem health and to highlight priorities for management. We demonstrate an application of this new framework —the Freshwater Health Index (FHI) — in the Dongjiang River Basin in southern China, where stakeholders are addressing multiple and conflicting freshwater demands. By combining empirical and modeled datasets with surveys to gauge stakeholders' preferences and elicit expert information about governance mechanisms, the FHI helps stakeholders understand the status of freshwater ecosystems in their basin, how ecosystems are being manipulated to enhance or decrease water-related services, and how well the existing water resource management regime is equipped to govern these dynamics over time. This framework helps to operationalize a truly integrated approach to water resource management by recognizing the interplay between governance, stakeholders, freshwater ecosystems and the services they provide. [ABSTRACT FROM AUTHOR]

The impacts of vegetation fires on ecosystems are complex and varied affecting a range of important ecosystem services. Fire has the potential to affect the physicochemical and ecological status of water systems, alter several aspects of the carbon cycle (e.g. above- and below-ground carbon storage) and trigger changes in vegetation type and structure. Globally, fire is an essential part of land management in fire-prone regions in, e.g. Australia, the USA and some Mediterranean countries to mitigate the likelihood of catastrophic wildfires and sustain healthy ecosystems. In the less-fire prone UK, fire has a long history of usage in management for enhancing the productivity of heather, red grouse and sheep. This distinctly different socioeconomic tradition of burning underlies some of the controversy in recent decades in the UK around the use of fire. Negative public opinion and opposition from popular media have highlighted concerns around the detrimental impacts burning can have on the health and diversity of upland habitats. It is evident there are many gaps in the current knowledge around the environmental impacts of prescribed burning in less fire-prone regions (e.g. UK). Land owners and managers require a greater level of certainty on the advantages and disadvantages of prescribed burning in comparison to other techniques to better inform management practices. This paper addresses this gap by providing a critical review of published work and future research directions related to the impacts of prescribed fire on three key aspects of ecosystem services: (i) water quality, (ii) carbon dynamics and (iii) habitat composition and structure (biodiversity). Its overall aims are to provide guidance based on the current state-of-the-art for researchers, land owners, managers and policy makers on the potential effects of the use of burning and to inform the wider debate about the place of fire in modern conservation and land management in humid temperate ecosystems. [ABSTRACT FROM AUTHOR]

Water monitoring technologies are widely used for contaminants detection in wide variety of water ecology applications such as water treatment plant and water distribution system. A tremendous amount of research has been conducted over the past decades to develop robust and efficient techniques of contaminants detection with minimum operating cost and energy. Recent developments in spectroscopic techniques and biosensor approach have improved the detection sensitivities, quantitatively and qualitatively. The availability of in-situ measurements and multiple detection analyses has expanded the water monitoring applications in various advanced techniques including successful establishment in hand-held sensing devices which improves portability in real-time basis for the detection of contaminant, such as microorganisms, pesticides, heavy metal ions, inorganic and organic components. This paper intends to review the developments in water quality monitoring technologies for the detection of biological and chemical contaminants in accordance with instrumental limitations. Particularly, this review focuses on the most recently developed techniques for water contaminant detection applications. Several recommendations and prospective views on the developments in water quality assessments will also be included. [ABSTRACT FROM AUTHOR]

Groundwater should be considered as the most important drinking water resource in arid/semi-arid regions such as Karaj, Iran. Provision of drinking water with a preeminent quality is, accordingly, a real matter of concern in these regions. Despite being an essential factor for rating of under exploitation water wells, Water Quality Index (WQI) entails conflicting issues. As a result, Multiple-criteria decision making (MCDM) models, such as Technique for order preference by similarity to ideal solution (TOPSIS), Compromise Programing (CP) and Ordered Weighted Averaging (OWA) operators were adopted to alleviate contradictions involving WQI index. In the current paper, compromise programming was utilized assuming p = 1&2 and the average value of ranks attained from all the above MCDMs (Averaged value rating) was correspondingly cited as a rating reference. Putting the above MCDM models into practice, ultimately, led to striking variations not only in the rankings but in category of water wells. It was clarified that compromise programming when p values are assumed to be 1 and 2 (CP (p = 1) & CP (p = 2)), TOPSIS and OWA could be recognized as proper techniques to eliminate contradictions involving ranking by WQI index. [ABSTRACT FROM AUTHOR]

While 884 million people worldwide lack access to clean water, millions live in flood-prone regions. Unexpected flooding increases risk of diarrheal diseases and is expected to occur with increased frequency in the 21st century. Water insecurity is linked to mental distress in water scarce regions, yet this construct has not been examined closely among populations living in flood-prone regions. This paper examines how differences in water sources and lifestyle among Tsimane’ forager-horticulturalists in lowland Bolivia are related to water insecurity after a historic flood in 2014, and in turn, how water insecurity is associated with diarrhea and dehydration. Pre-flood data come from qualitative interviews with 36 household heads, anthropometrics, participant observation, and water quality analysis between September 2013–January 2014 used to create a locally-adapted water insecurity questionnaire. Water insecurity was measured after the historic flood; no pre-flood water insecurity measures are available. Post-flood data were collected through surveys, water quality analysis, and health exams using near-exhaustive sampling in two villages, yielding 118 adults and 115 children (aged 2–12 years) in 62 households between March–April 2014. Overall, 89% of adults reported medium or high water insecurity. Only hand-pumps tested negative for pathogenic bacteria both pre- and post-flood. Tobit regressions suggest that hand-pumps (when available) and adult age were associated with lower water insecurity scores. Multiple logistic regressions suggest that adults with high water insecurity were more likely to report diarrhea than adults with low (Odds Ratio [OR] 9.2; 95% CI: 1.27–67.1). Children from households with medium (OR: 6.8; 95% CI: 1.41–32.5) or high (OR: 14.0; 95% CI: 2.40–81.5) water insecurity had significantly higher odds of dehydration than children in households with low water insecurity. Catastrophic flooding may systematically increase dimensions of household water insecurity. This research suggests an experience-based measure of water insecurity is associated with objective health outcomes. [ABSTRACT FROM AUTHOR]

Life and the sustainable growth of socioeconomic sectors such as agriculture and industry depend on groundwater, particularly in arid and semi-arid regions where surface water resources are limited. The objectives of the current study are to characterize groundwater chemistry and assess its suitability for industrial usage in the Guanzhong Basin located in the semi-arid region of northwest China. To better understand the hydrogeochemistry in the study area, statistical analysis, ionic plots and Pearson's correlation analysis were conjunctively used. Finally, a novel industrial water quality index (IndWQI) model was developed in this paper to determine the overall industrial water quality based on scaling, corrosion, and foaming coefficients as well as some physicochemical parameters. The contribution of each parameter to the overall industrial water quality was determined using multivariate statistical analysis approaches. The findings reveal that dissolution of minerals such as calcite, dolomite, anhydrite and gypsum regulate the groundwater geochemistry in the study area. In addition, human activities influence the groundwater quality in the study area. According to the novel IndWQI approach, 78.95 % of the confined water samples and 74.51 % of the phreatic water samples have excellent or good quality, and can be safely used for industrial boilers. The geospatial analysis shows that the most contaminated groundwater samples are mainly located in northeast Xi'an and the northeast region of the Guanzhong Basin. The IndWQI model is trustworthy, as it can combine several water quality indices and give an instantaneous impression of the whole groundwater quality for industrial uses. It can serve as a benchmark for other areas across the world with a comparable climate. [ABSTRACT FROM AUTHOR]

The delay in reporting high levels of lead in Flint drinking water, following the city's switch to the Flint River as its water supply, was partially caused by the biased selection of sampling sites away from the lead pipe network. Since Flint returned to its pre-crisis source of drinking water, the State has been monitoring water lead levels (WLL) at selected “sentinel” sites. In a first phase that lasted two months, 739 residences were sampled, most of them bi-weekly, to determine the general health of the distribution system and to track temporal changes in lead levels. During the same period, water samples were also collected through a voluntary program whereby concerned citizens received free testing kits and conducted sampling on their own. State officials relied on the former data to demonstrate the steady improvement in water quality. A recent analysis of data collected by voluntary sampling revealed, however, an opposite trend with lead levels increasing over time. This paper looks at potential sampling bias to explain such differences. Although houses with higher WLL were more likely to be sampled repeatedly, voluntary sampling turned out to reproduce fairly well the main characteristics (i.e. presence of lead service lines (LSL), construction year) of Flint housing stock. State-controlled sampling was less representative; e.g., sentinel sites with LSL were mostly built between 1935 and 1950 in lower poverty areas, which might hamper our ability to disentangle the effects of LSL and premise plumbing (lead fixtures and pipes present within old houses) on WLL. Also, there was no sentinel site with LSL in two of the most impoverished wards, including where the percentage of children with elevated blood lead levels tripled following the switch in water supply. Correcting for sampling bias narrowed the gap between sampling programs, yet overall temporal trends are still opposite. [ABSTRACT FROM AUTHOR]

Optimisation of the operation of water distribution systems has been an active research field for almost half a century. It has focused mainly on optimal pump operation to minimise pumping costs and optimal water quality management to ensure that standards at customer nodes are met. This paper provides a systematic review by bringing together over two hundred publications from the past three decades, which are relevant to operational optimisation of water distribution systems, particularly optimal pump operation, valve control and system operation for water quality purposes of both urban drinking and regional multiquality water distribution systems. Uniquely, it also contains substantial and thorough information for over one hundred publications in a tabular form, which lists optimisation models inclusive of objectives, constraints, decision variables, solution methodologies used and other details. Research challenges in terms of simulation models, optimisation model formulation, selection of optimisation method and postprocessing needs have also been identified. [ABSTRACT FROM AUTHOR]

The models for the end-user demand give a detailed description of the water request, which takes into account the consumes of each dwelling. Therefore, these approaches can model the water demand at WDS nodes by aggregating the single request of each user. The effectiveness of a novel approach the Overall Pulse model (OP)- to describe the aggregated water demand has been tested. In fact, the OP model, unlike the commonly used rectangular pulse models (e.g. PRP, NSRP), does not aim to reconstruct single demand pulses as they occur when home faucets and hydro-sanitary appliances are operated, but allows the generation of the water demand as it is observed at the house water meter. This feature makes the model very versatile, allowing the direct modeling of either a single user or of a group of n users. The possibility of ‘pre-aggregation’ of the water demand makes it easier to take into account the spatial variability of the model parameters. In the paper, the performance of the OP model is investigated, and to this aim the generated time series are compared with the observed ones of real users. In addition, the comparison of series obtained by means of the classical PRP approach and of the OP model show the effectiveness of the latter. [ABSTRACT FROM AUTHOR]

Diverse studies have shown that mixing within pipe junctions is neither complete nor instantaneous. However, these studies have focused in understanding mixing phenomena at junctions, without applying these results in water quality modeling of water distribution networks. This paper focuses on the application of both the complete and incomplete mixing models to model water quality in water distribution networks. Hydraulic networks are modelled in EPANET and EPANET-BAM, and the concentrations and their distributions are compared. Results show that there is little difference between the two mixing models, so water quality modeling might be done by using EPANET and its complete mixing model. [ABSTRACT FROM AUTHOR]

Pesticides are a non-point source of pollution affecting the quality of drinking water supplies and aquatic environments. Many facilities are set up to reduce the transfer of pesticides from agricultural parcels into the environment, thereby preventing their input into water bodies. Artificial ponds collecting runoff and erosion fluxes represent a complementary tool for mitigating pesticide transfer. Ponds are free-water surface constructed wetlands, rarely dry out, and do not exceed 2 m in depth. Their main compartments include a water column, a sediment layer, living organisms, and suspended particles. The dissipation potential of ponds is due to a combination of physical, chemical, and biological processes that pesticides undergo in an interplay between different pond compartments. Although many studies on the dissipation potential of ponds focus on nitrates and suspended sediments, very little is known about the behavior of pesticides. Also, most studies evaluate a process individually without emphasizing its eventual interaction with other processes. Few papers address and compare mathematical formulations of pesticide transfer and transformation processes for artificial pond modeling. In this review, we investigate the interactions and contribution of multiple processes to artificial pond dissipation function by comparing their rates evaluated at different scales. We also discuss the mathematical formulations of these processes and their relationship with pesticide properties. Our evaluation suggests that quantifying the contribution of each process to pesticide dissipation in artificial ponds is an important tool for the hierarchization of dissipation processes. We believe that quantification and hierarchization may improve the estimation of overall artificial pond efficiency. We anticipate this work to be the basis for developing a process-based model of pesticide fate in artificial ponds. The model will be particularly helpful in setting up the dimensioning criteria to design performant and efficient ponds in order to mitigate pesticide transfer into the environment. [Display omitted] • Identification and formalisms of dissipation processes of pesticides in artificial ponds. • Sorption as a key process for lowly soluble and hydrophobic pesticide dissipation. • Biotransformation enhanced in water-substrate interfaces favoring microbial activity. • Interplay of processes contributes more significantly to the dissipation of pesticides. [ABSTRACT FROM AUTHOR]

The Adriatic Sea countries face significant problems regarding cross-border water resources management. DRINKADRIA project aims at developing a common methodological framework, for efficient and effective cross border water supply and resources management, taking into consideration different resources types (surface and ground water) emphasizing in drinking water supply intake. The common methodology is based in four pillars: climate characteristics and the climate change, water resources availability, water resources quality and finally water resources management. The present paper assesses both present and future vulnerability of water resources based on a common methodology and estimates the integrated vulnerability index for the Adriatic Sea region and the Corfu test area. [ABSTRACT FROM AUTHOR]

The paper presents the methodology for determining the operating and technical indicators for a preliminary assessment of the elements of water supply system (WSS) such as water treatment plants. The necessary data and system of technical indicators (TI) evaluation using the multi-objective optimization and Failure Mode and Effects Analysis (FMEA) are defined. The proposed methodology allows for the selection and ranking of WSS critical elements for more detailed analyses and suggestions of the type of renewal, including the estimated financial costs. Water treatment plants can be assessed by means of the specific part of the methodology. With respect to the water treatment plants the authors of the methodology realize that it is hard to generalize the entire audit since there are many types of water treatment plants as well as technological elements used. The proposed set of assessment indicators is based on the function of the water treatment plant, i.e. production of drinking water in the required quantity and quality. When assessing the technical condition of the water treatment plant this facility may not be viewed simply in structural and technical terms but it is absolutely necessary and much more important to assess it in technological terms. [ABSTRACT FROM AUTHOR]

Historically, water scarcity has been understood to result from unfavorable climatological and hydrological factors. From this perspective, infrastructural solutions that augment water supplies, such as desalination, are seen as the way to overcome physical resource limits and resolve water scarcity. Drawing on theories of scarcity, risk perception, trust, and governance, we argue that past experiences with poor water quality and a long-standing mistrust of water providers create a particular mode of water scarcity: perceptual scarcity. This paper presents findings from household surveys conducted in two arid Latin American cities where large-scale desalination projects have been undertaken to provide potable water. While both projects use state-of-the-art desalination technology, our survey results indicate that the majority of respondents do not drink desalinated water from their taps and purchase bottled water instead. Our results show that, despite significant investments in infrastructure, respondents still lack an adequate supply of water that is perceived to be fit for human consumption. The two case studies provide empirical evidence that challenges the assumption that desalination technology will resolve water quality and water scarcity concerns. We conclude that institutional investments that promote a more reliable and trustworthy water governance system are as important as investments in physical infrastructure. [ABSTRACT FROM AUTHOR]

Detection of enzymatic activities has been proposed as a rapid surrogate for the culture-based microbiological pollution monitoring of water resources. This paper presents the results of tests on four fully automated prototype instruments for the on-site monitoring of beta- d -glucuronidase (GLUC) activity. The tests were performed on sediment-laden stream water in the Hydrological Open Air Laboratory (HOAL) during the period of March 2014 to March 2015. The dominant source of faecal pollution in the stream was swine manure applied to the fields within the catchment. The experiments indicated that instrument pairs with the same construction design yielded highly consistent results (R 2 = 0.96 and R 2 = 0.94), whereas the results between different designs were less consistent (R 2 = 0.71). Correlations between the GLUC activity measured on-site and culture-based Escherichia coli analyses over the entire study period yielded R 2 = 0.52 and R 2 = 0.47 for the two designs, respectively. The correlations tended to be higher at the event scale. The GLUC activity was less correlated with suspended sediment concentrations than with E. coli , which is interpreted in terms of indicator applicability and the time since manure application. The study shows that this rapid assay can yield consistent results over a long period of on-site operation in technically challenging habitats. Although the use of GLUC activity as a proxy for culture-based assays could not be proven for the observed habitat, the study results suggest that this biochemical indicator has high potential for implementation in early warning systems. [ABSTRACT FROM AUTHOR]

This paper aims to examine if users perceive a difference in tap water quality supplied by publicly owned or privately owned water operators. More generally, this paper analyses whether and how certain relevant variables affect water quality using customer satisfaction as an indicator of water quality. Since the decision to privatise the service may be influenced by environmental and geographical factors as well as water operators' characteristics, data were analysed using a treatment effects model, in which privatisation was considered an endogenous binary treatment variable. Data were from a sample survey of 485 students enrolled at the University of Pisa (Italy). Our results suggest that water operator ownership influences the perceived quality of the supplied tap water. Decision-makers should include water quality as a relevant issue when deciding whether to privatise water services management. In addition, since there is a relationship between the perception of tap water quality and the quality of public service provision, for policy makers, it is of utmost importance to highlight the areas where the lack of satisfaction is higher and to encourage investment and water quality improvement programmes in these contexts. • Water operator ownership influences the perceived quality of tap water. • Water quality perception is not always related to water standard compliance. • Perception of water quality relates to the quality of public service provision. • Perceived quality decreases when mixed or private firms manage the water service. [ABSTRACT FROM AUTHOR]

• Water accounts compiled reveal a serious problem of local water management. • The approach unveils the water flows to and from the city, as well as within it. • It shows issues of water quality and of industrial water productivity at local level. • This information can strongly support the local decision-making processes. Data management for decision support is a challenging aspect of any decision-making process. Water management is not an exception. The objective of this paper is to present a procedure for compiling water accounts at an urban level to support political decision-making processes with solid foundations. The System of Environmental-Economic Accounting for Water (SEEA-Water) was used for this purpose. The case study of Santo Domingo de los Colorados in Ecuador serves to illustrate the benefits and the limitations of the available data and to identify data gaps. The compilation of the SEEA-Water at a local level is a pioneering work. The results reveal the water flows (from the environment to the economy, within the economy, from the economy to the environment), water quality, and the contribution of water resources to different economic activities for the period 2014–2015 at the local level. The information was categorized for the water supply industry, the sewage industry, for the rest of the industries and services, and for the households. On the basis of our empirical example, this paper shows how SEEA-Water underpins informed decision-making on urban water management and serves to improve the quality of water-related data. [ABSTRACT FROM AUTHOR]

Sustainable development requires that resources use should be kept within boundary values. This paper provided a complete explanation of the theoretical concepts of the three-dimensional water footprint model (3D WF model) and improved the 3D WF model by extending it to both water quantity and water quality assessment perspectives. Size and depth of blue water footprint (BWF) and grey water footprint (GWF) help assess the sustainability of regional water resources in terms of both source and sink appropriation, which emphasizing the importance of freshwater resources as critical natural capital. Then, the improved 3D WF model was used to explore the sustainability of regional freshwater resource utilization by taking the freshwater resource utilization status of 31 provinces in mainland China as an example. The values of blue water footprint size (BWF size) and grey water footprint size (GWF size) in China from 2003 to 2015 were 575.6 billion m³ and 1552.3 billion m³, corresponding to the dominant factors of agricultural sources (64.0%) and domestic sources (75.3%), respectively. The high value areas of blue water footprint depth (BWF depth) and grey water footprint depth (GWF depth) were mainly located in North, East and Northwest China, with a high mismatch between freshwater resource stock and flow possession. After clustering, Xinjiang was in a source deficit dominated region; Beijing, Tianjin, Shaanxi, Shanghai and Henan were in a sink deficit dominated region; Ningxia, Hebei, Liaoning and Shandong were in a dual source and sink deficit region. The water footprint size (WF size) and water footprint depth (WF depth) reflect the intra- and intergenerational equity in the sustainable use of regional water resources, and the improved 3D WF distinguishes types of unsustainable regional water resources (source shortage or sink shortage, or both), which is important for raising awareness of water conservation among residents and helping managers to tailor water management policies to local conditions. • Improved 3D water footprint model to assess the sustainability of water appropriation in both water quality and quantity. • Water surplus and deficit ratios is developed to assess regional water use. • There are large differences in provincial freshwater resource depletion. • 3D Water footprint model is an extension of the sustainable representation of 2D water footprint model. [ABSTRACT FROM AUTHOR]

This paper reviews existing methods for assessing livestock water resource use, recognizing that water plays a vital role in global food supply and that livestock production systems consumes a large amount of the available water resources. A number of methods have contributed to the development of water resources use assessments of livestock production. The methods reviewed in this study were classified into three categories: water productivity assessments, water footprint assessments and life cycle assessments. The water productivity approach has been used to assess benefits derived from consumptive water use in livestock production; the water footprint approach has raised awareness of the large amounts of water required for livestock production; and life cycle assessments highlight the important connection between water resource use and local impacts. For each of the methods we distinguish strengths and weaknesses in assessing water resource use in livestock production. As a result, we identify three key areas for improvement: 1) both green and blue water resources should be included in assessments, and presented separately to provide informative results; 2) water quality should not be summarized within quantitative assessments of water resource use; and 3) methods for assessing water use in livestock systems must consider the alternative uses, multiple uses and benefits of a certain resource in a specific location. [ABSTRACT FROM AUTHOR]

In developing countries, access to public water services does not ensure clean or reliable supply; nor does it indicate equitable delivery. Further, concentrating on accessibility offers a biased picture of performance and exaggerates the level of accomplishment, while concealing the presence of major challenges to further progress. Through a qualitative study, this article explores the quality dimension of water supply services in Abuja city, Nigeria. Data were obtained from in-depth interviews with residents and city officials, supplemented by personal observations. Lack of reliability, low water pressure, inefficient billing systems, inadequate facility maintenance, spatial inequality in service delivery, and lack of public involvement were found to immensely undermine the delivery of water services in the city. The paper concludes by suggesting ways of enhancing the quality of water services in Abuja and other developing areas. [ABSTRACT FROM AUTHOR]

The purpose of developing alternate water sources is to secure water sources of sufficient quantity and high quality due to water quality and/or quantity problems of an existing water source and, thereby, raise the level of consumer satisfaction. Considering the enormous costs and the effects to the consumers and operation of water supply enterprises, a technique to support long term management of water supply systems is needed. In this paper a System Dynamics computer simulation model was developed to evaluate the effects of alternate water source development. The System Dynamics model was used for the simulation of the effects of the alternate water source development project in Busan, South Korea. [ABSTRACT FROM AUTHOR]

Cost-effective management of leakage has driven the sectorization of water supply networks into discrete areas that are referred to as District Metered Areas (DMAs). The resulting change in network topology has a major impact on the hydrodynamic conditions and consequently changes in water quality. This paper investigates the impact of DMAs on the potential for discoloration by analysing the spatio-temporal distribution of historic discoloration-related customer contacts for a UK water company. The results demonstrate that the sectorization of networks could have a negative effect on discolouration. A management strategy to reduce the risk of discoloration in DMA-based systems is discussed. [ABSTRACT FROM AUTHOR]

Analysing water networks online should not be constrained to classic hydraulic simulations. Including other processes can give a much better global view of what is happening in the network. Water quality modelling [1], event detection [2] or online source identification [3], for example, are some of the processes that can be considered as part of a global water network analysis. In the context of this paper, the online analysis is understood as getting the most of the water network current state based on the information available from it. The work presented describes a system aimed to support the coordination of different processes working on the online analysis of water networks. Several aspects of Petri nets [4] are used for modelling the interaction among the processes. The system is described from a software engineering perspective but the application is focused on the benefits for running online water distribution system analysis. [ABSTRACT FROM AUTHOR]

This paper presents a comparison of two different modelling approaches for the generation of residential water demand pulses as Poisson processes. Both approaches are able to preserve the mean value of daily water demand. The main difference lies in the fact that the first considers the correlation between pulse durations and intensities whereas the second neglects it. Overall, the results of the applications aimed at reproducing the measured pulses in two households show that the increase in parameterization burden associated with taking correlation into account delivers a considerable improvement in the quality of model predictions. [ABSTRACT FROM AUTHOR]

Supplying modern water systems in smart cities requires the ability to monitor water quality in the production plants and the distribution network. Protection against accidental or intentional events is usually based on an Early Warning Detection System (EWDS) to minimize the impact of any contamination [1]. A major issue is positioning online sensors along the water distribution network to ensure the best protection at minimum cost. Several contributions for tackling such problem have been proposed during the last decade, including a scientific challenge comparing 14 methodologies [2] and two reviews of about 150 articles [3,4]. Currently there is no consensus about algorithms or design objectives to use, and such a problem is NP-hard [5,6]. In this paper, a greedy approach is proposed to near-optimally solve the sensor placement problem dealing with large-scale water systems. This methodology is designed to integrate both the specificity of the studied network (expert/prior knowledge) and flexibility related to the uncertainty of the nature, time, and duration of contamination injections. The method is illustrated to minimize the expected fraction of the exposed population on the largest network in France (about 100,000 nodes, 600,000 connections, above 8,000 km of pipes). Costly approaches in terms of computation time, such as MIP (Mixed-Integer Programming) and exhaustive search cannot scale to large networks. A sensitivity analysis is presented using the greedy approach on a sub-network which leads to choose the number of sufficient contamination simulations and the concentration threshold used to detect contaminations. The extensive experiments allow us to highlight the effectiveness and the rapidity of the proposed approach. [ABSTRACT FROM AUTHOR]

Water quality forecasting can provide useful information for public health protection and support water resources management. In order to forecast water quality more accurately, this paper proposes a novel hybrid model by combining data decomposition, fuzzy C-means clustering and bidirectional gated recurrent unit. Firstly, the original water quality data is decomposed into several subseries by empirical wavelet transform, and then, the decomposed subseries are recombined by fuzzy C-means clustering. Next, for each clustered series, bidirectional gated recurrent unit is applied to develop prediction model. Finally, the forecast result is obtained by the summation of the predictions for the subseries. The proposed forecast model is evaluated by the water quality data of Poyang Lake, China. Results show that the proposed forecast model provides highly accurate forecast result for all of the six water quality data: the average of MAPE of the forecast results for the six water quality datasets is 4.59% for 7 day ahead prediction. Furthermore, our model shows better forecast performance than the other models. Particularly, compared with the single BiGRU model, MAPE decreased by 32.86% in average. Results demonstrate that the proposed forecast model can be used effectively for water quality forecasting. [Display omitted] • A new real-time data decomposition strategy is proposed. • More accurate prediction result is obtained by clustering the decomposed subseries. • Bidirectional gated recurrent unit has a great simulation capacity. • Proposed model is a powerful tool to predict water quality. [ABSTRACT FROM AUTHOR]

Packaged “sachet” water has become the primary drinking water source for millions of West Africans despite ongoing controversy over inadequate management of the new waste streams created by all the plastic wrappers. While recent literature from Ghana has shown that municipal water rationing and lower socioeconomic status tend to drive sachet consumption at the metropolitan scale, some low-income communities with a reliable piped water supply still exhibit diverse drinking water-seeking behaviours. This paper explores the drinking water landscape of one poor, informal community in Ashaiman, Ghana, as a case study of the individual- and community-level factors that shape household drinking water decisions. Using the results of a water questionnaire completed by 95 households and the transcripts of four focus groups, our findings suggest that, after controlling for demographics, sachet water consumption is associated with proxies for higher disposable income and lack of knowledge about household water treatment methods, while social processes and attitudes toward water quality do not seem to drive drinking water decisions. This community presents a paradoxical drinking water landscape, as poverty abounds despite excellent piped water access, and low-income households with slightly greater means tend to opt for packaged water as opposed to being driven to it by piped water shortages. These nuances in drinking water purchasing behaviour can inform policy and planning for drinking water provision in urban slums across the region. [ABSTRACT FROM AUTHOR]

The narrative of environmental justice is powerfully and passionately advocated by researchers, practitioners and activists across scale and space. Yet, because these struggles are multifaceted and pluralistic, rooted in complex, evolving “socio-material-political interminglings” the concept is difficult to grasp, and even harder to realise. Recent literature raises concerns as to what makes for environmental injustices, how injustices are defined, classified as urgent and/or critical, by whom and why, how they gain political attention, etc. This paper draws attention to these issues by contrasting the largely untold, nonetheless entrenched and enduring “old” water supply injustices in the Darjeeling region of the Eastern Himalaya in India with articulate contestations relating to the speedy advancement of “new” hydropower projects here. Water supply problems in the Darjeeling region are particularly wicked – nested in fractious ethnicity–identity political conflicts. These complex local realities tend to obscure the everyday challenges relating to water as well as render these problems spatially anecdotal. What happens – or does not – around water here is certainly unique, yet comparison to other struggles in other settings show that locational and environmental politics provide critical evidence to question the several implicit universalisms in relation to water justice. [ABSTRACT FROM AUTHOR]

Models like SWAP, HYDRUS and SALTMED compute crop water uptake under osmotic stress with a dimensionless piecewise linear or S-shaped reduction function. Parameters for these functions, to reduce water uptake, corresponds normally to the Maas and Hoffman salinity threshold and slope values. Unfortunately, extensive crop- and site-specific calibration of the parameters is required. This is because these values, amongst other reasons, serve only as guidelines and express salt tolerance at a time and root-zone average soil salinity and not local total potential heads. In this paper an alternative model (Soil WAter Management Program, SWAMP), that does not rely on these parameters and functions were presented and evaluated. The algorithm used by SWAMP to simulate the water supply of a rooted soil layer and hence water uptake, under decreasing matric potentials was adapted to include the effect of decreasing osmotic potentials. Data from a lysimeter trial was used to evaluate SWAMP. The model was calibrated to represent the soil conditions of the trial, i.e. peas and maize were irrigated with EC's between 20 and 600 mS m −1 and grown in sand to sandy loam soils with water tables of the same quality. Under these osmotic stress conditions, SWAMP was able to simulate weekly water uptake of both crops grown on both soils well, i.e. the aggregated accuracy, correlation and pattern performance ( I SWAMP ) were above 75%. No macro-pattern was observed. Thus, the water uptake residuals contain no structure that is not accounted for in the algorithm and parameters. No extensive calibration was necessary because the parameters for the algorithm were calculated from easily measured inputs. From the three most sensitive parameters, only the critical leaf water potential of a crop might be difficult to obtain. SWAMP contains default values for a number of crops. A model is, therefore, presented that simulate the change in osmotic stress with changing soil water content and that does not rely on the salinity threshold and slope parameters. [ABSTRACT FROM AUTHOR]

The primary effects of droughts on river basins include both depleted quantity and quality of the available water resources, which can render water resources useless for human needs and simultaneously damage the environment. Isolated water quality analyses limit the action measures that can be proposed. Thus, an integrated evaluation of water management and quality is warranted. In this study, a methodology consisting of two coordinated models is used to combine aspects of water resource allocation and water quality assessment. Water management addresses water allocation issues by considering the storage, transport and consumption elements. Moreover, the water quality model generates time series of concentrations for several pollutants according to the water quality of the runoff and the demand discharges. These two modules are part of the AQUATOOL decision support system shell for water resource management. This tool facilitates the analysis of the effects of water management and quality alternatives and scenarios on the relevant variables in a river basin. This paper illustrates the development of an integrated model for the Llobregat River Basin. The analysis examines the drought from 2004 to 2008, which is an example of a period when the water system was quantitative and qualitatively stressed. The performed simulations encompass a wide variety of water management and water quality measures; the results provide data for making informed decisions. Moreover, the results demonstrated the importance of combining these measures depending on the evolution of a drought event and the state of the water resources system. [ABSTRACT FROM AUTHOR]

Lack of access to safe drinking water remains a present concern in many developing countries, particularly in rural locations. Membrane water treatment technologies have the potential to remove microbiological and chemical contaminants reliably and simultaneously from a wide range of water sources. When powered by renewable energy, these systems are autonomous and have the ability to ‘leapfrog’ over installation of traditional infrastructure for electricity and water supply to reach remote communities. In this paper, current estimated costs for water, membrane plants and infrastructure are compared to indicate the window of opportunity for these exciting renewable energy powered membrane (RE-membrane) technologies. General estimated costs for decentralized membrane systems are within the range of some untreated water costs in developing countries. Specific system costs, however, are very process and location dependent. The appropriateness of a successful approach thus depends partially on careful examination of these parameters. In view of the comparisons made here, the biggest hurdle to adoption of the RE-membrane technology in a remote location may not be cost, but rather sustainability issues such as the lack of skilled personnel for operation and maintenance, service networks, availability of spare parts, socio-economic integration and adaptive capacity of communities to transfer and develop technology appropriate to local needs and circumstances. [ABSTRACT FROM AUTHOR]