Estimation of the Change in Lake Water Level by Artificial Intelligence Methods

In this study, five different artificial intelligence methods, including Artificial Neural Networks based on Particle Swarm Optimization (PSO-ANN), Support Vector Regression (SVR), Multi- Layer Artificial Neural Networks (MLP), Radial Basis Neural Networks (RBNN) and Adaptive Network Based Fuzzy Inference System (ANFIS), were used to estimate monthly water level change in Lake Beysehir. By using different input combinations consisting of monthly Inflow - Lost flow (I), Precipitation (P), Evaporation (E) and Outflow (O), efforts were made to estimate the change in water level (L). Performance of models established was evaluated using root mean square error (RMSE), mean square error (MSE), mean absolute error (MAE) and coefficient of determination (R²). According to the results of models, ε-SVR model was obtained as the most successful model to estimate monthly water level of Lake Beysehir.     

Water Demand Forecasting Model for the Metropolitan Area of São Paulo,Brazil

This work is concerned with forecasting water demand in the metropolitan area of São Paulo (MASP) through water consumption, meteorological and socio-environmental variables using an Artificial Neural Network (ANN) system. Possible socio-environmental and meteorological conditions affecting water consumption at Cantareira water treatment station (WTS) in the MASP, Brazil were analyzed for the year 2005. Eight model configurations were developed and used for the Cantareira WTS. The best performance was obtained for 12-h average of the input variables. The ANN model performed best with three times steps in advance. The hourly forecasting was obtained with acceptable error levels. Model results indicate an overall tendency for small errors. The proposed method is useful tool for water demand forecasting and water systems management. The paper is an important contribution since it takes into account weather variables and introduces some diagnostic studies on water consumption in one of the largest urban environments of the planet with its unique peculiarities such as anthropic affects on weather and climate that feeds back into the water consumption. The averaging is a low pass filter indeed and we used it to improve Signal to Noise Ratio (SNR).     

Modeling the Effect of Cistern Size,Soil Type,and Irrigation Scheduling on Rainwater Harvesting as a Stormwater Control Measure

Urban stormwater runoff could have negative impacts on water resources and the environment. Rainwater Harvesting (RWH) can serve both as a stormwater control and water conservation measure. Cistern size and irrigation scheduling are two of the factors that directly impact the total runoff from a residential unit with a RWH system and the amount of potable water used for irrigation. The effectiveness of RWH was evaluated for four soil types; Sand, Sandy Loam, Loamy Sand, and Silty Clay, with a root zone of 15.2 cm using three irrigation scheduling methods (Evapotranspiration (ET)-based, soil moisture-based, and time-based), and five cistern sizes. Total runoff volumes and total supplemental potable water used were compared among the three irrigation scheduling systems and a control treatment without RWH. A model was developed to simulate the daily water balance for the treatments. Irrigation and runoff volumes were compared for the various scenarios. Silty clay soil resulted with 83 % more runoff than Sandy soil, while Sandy soil required on average 58 % more supplemental water than Silty Clay soil. On average, the 833 L cistern resulted with 41 % savings in water supply and 45 % reduction in total runoff. Results showed that the greatest volumes of runoff predicted were for the silty clay soil Control Treatment using a time-based irrigation scheduling method, while the least volumes calculated were for the sandy loam soil time-based irrigation scheduling treatment with 833 L cistern size. The greatest volumes of total supplemental water predicted were for sandy loam soil Control Treatment, while the least volumes were for silty clay soil ET-based irrigation scheduling treatment with 833 L cistern size. Regression equations were developed to allow for users to select a RWH cistern size based on the amount of water they want to save or runoff to reduce.     

Assessing Stability and Dynamics in Flood Risk Governance

European urban agglomerations face increasing flood risks due to urbanization and the effects of climate change. These risks are addressed at European, national and regional policy levels. A diversification and alignment of Flood Risk Management Strategies (FRMSs) can make vulnerable urban agglomerations more resilient to flooding, but this may require new Flood Risk Governance Arrangements (FRGAs) or changes in existing ones. While much technical knowledge on Flood Risk Management is available, scientific insights into the actual and/or necessary FRGAs so far are rather limited and fragmented. This article addresses this knowledge gap by presenting a research approach for assessing FRGAs. This approach allows for the integration of insights from policy scientists and legal scholars into one coherent framework that can be used to identify Flood Risk Management Strategies and analyse Flood Risk Governance Arrangements. In addition, approaches for explaining and evaluating (shifts in) FRGAs are introduced. The research approach is illustrated by referring to the rise of the Dutch risk-based approach called ‘multi-layered safety’ and more specifically its application in the city of Dordrecht. The article is concluded with an overview of potential next steps, including comparative analyses of FRGAs in different regions. Insights in these FRGAS are crucial to enable the identification of action perspectives for flood risk governance for actors at the level of the EU, its member states, regional authorities, and public-private partnerships.     

Decision Support for Mainstreaming Climate Change Adaptation in Water Resources Management

Climate change adaptation (CCA) has recently emerged as a new fundamental dimension to be considered in the planning and management of water resources. Because of the need to consider the already perceived changes in climate trends, variability and extremes, and their interactions with evolving social and ecological systems, water management is now facing new challenges. The research community is expected to contribute with innovative methods and tools to support to decision- and policy-makers. Decision Support Systems (DSSs), have a relatively long history in the water management sector. They are usually developed upon pre-existing hydrologic simulation models, providing interfaces for facilitated use beyond the limited group of model developers, and specific routines for decision making (e.g. optimization methods). In recent years, the traditional focus of DSS research has shifted away from the software component, towards the process of structuring problems and aiding decisions, thus including in particular robust methods for stakeholders’ participation. The paper analyses the scientific literature, identifies the main open issues, and proposes an innovative operational approach for the implementation of participatory planning and decision-making processes for CCA in the water domain.     

Integrated Ecosystem Management of River Basins and the Coastal Zone in Brazil

International society has begun to consider river basins and the coastal zone as one management unit that requires an ecosystem approach. Various countries have undertaken initiatives since the 1970s and have improved the approach to integrated coastal zone management. Brazil has not been one of them. Its sector-based approach to most environmental issues started in the 1980s with the National Environmental Policy Act (Law 6,938/1981). The National Coastal Zone Management Plan (NCZMP) was then approved by Law 7,661 in 1988. Shortly thereafter, the 1988 Brazilian Constitution was enacted, which established the environment as a common good to be used by the entire society but in such a way as to prevent environmental degradation and conserve its quality for present and future generations. The National Water Resources Policy (NWRP) was not enacted until 1997 (Law 9,433/1997). This law established that water resource management in Brazil must take into account estuarine ecosystems and the coastal zone, using an integrated approach. Only in 2006 did the National Water Resources Council (NWRC) create a technical chamber dedicated to developing regulatory measures for integrated management in Brazil. There has been substantial discussion and various proposals to implement it, as outlined in this article. This paper concludes with suggestions for implementing integrated river basin and coastal zone management in Brazil.     

Spatiotemporal Change of Blue Water and Green Water Resources in the Headwater of Yellow River Basin,China

The headwater of Yellow River Basin (HYRB) is crucial for the water resources of the whole basin in Northwest China. Based on the semi-distributed hydrological model “Soil and Water Assessment Tool” (SWAT), the spatiotemporal change trends of blue water and green water resources in the HYRB were analyzed quantificationally. By using the Sequential Uncertainty Fitting program (SUFI-2), the model was calibrated at Tangnaihai hydrological station and uncertainty analysis was performed. The results showed that the total water resources decreased by 1.08 billion m³ over the past five decades in the HYRB. Blue water and green water storage (soil water) presented the downtrend, while green water flow (actual evapotranspiration) increased between 1961 and 2010. The decrease in blue water resources were mainly attributed to the decrease in precipitation in the southwest parts of the study area while the increase in actual evapotranspiration and the decrease in soil water were the results of the uptrend of air temperature. In 1990s, an enormous transition occurred between the blue water (24.86 %) and green water flow (63.46 %). At seasonal scale, the largest down trend of blue water and uptrend of actual evapotranspiration all occurred in autumn. The decrease ratios of them were 88.3 and 83.1 % in inter-annual variation, respectively. The study can provided a scientific basis for integrated water resources management under the background of global climate change and human activity.     

A Solution for Flood Control in Urban Area: Using Street Block and Raft Foundation Space Operation Model

The overdevelopment of urban area has decreased the city’s ground permeability and increased its surface runoff. Moreover, the urban area existing flood control system meets the high risk and new challenge for water resource management due to global warming and climate change. A huge idle raft foundation space of existing buildings in urban area is found to be practicable solution for urban flood control systems. Through the operation model using street block and raft foundation space in urban area can effectively reduce peak runoff during typhoon seasons and extreme rainfall periods. This study selected a certain street block in Taipei City and 47 typical typhoons as validation, and constructed a Street Block-Raft Foundation flood control model (SB-RF model). Firstly, the optimal solution for reducing peak runoff for the 47 typhoons was obtained using Linear Programming. Data from the optimal solution and Back Propagation Neural Network were then used to simulate the SB-RF model flood control. This paper not only demonstrates the effectiveness of proposed model in controlling urban floods, but establishes an expected average peak runoff reduction rate and proposes a methodology for optimizing flow controls. Results are proved to be useful as reference for urban flood control for urban area such as Taipei City during typhoon season.     

Understanding the Role of Urban Road Surface Characteristics in influencing Stormwater Quality

Urban road surfaces are one of the most important stormwater pollution sources. Asphalt and concrete road surfaces are typical road types in China and have different characteristics such as roughness, textures and infiltration rates. This could lead to differences of collecting and retaining pollutants. In this context, designing stormwater treatment for different road surfaces respectively is crucial to effectively minimize the stormwater deterioration. This closely depends on an in-depth understanding of stormwater quality characteristics on urban road surfaces. This research study investigated the stormwater quality characteristics on typical asphalt and concrete surfaces. The research outcomes show that road surface characteristics could play a more important role in influencing the resulting stormwater runoff quality than rainfall characteristics. Additionally, asphalt surface due to the relatively rough nature could play a more important role in influencing the overall pollutant export characteristics from urban road surfaces. It is also noted that there are notable differences in pollutant wash-off processes on different surfaces, where the wash-off process on asphalt surfaces tends to be a transport limiting process, while the wash-off process on concrete surfaces tends to be a source limiting process. These results can contribute to stormwater treatment design enhancement for urban roads such as treatment placement, rainfall event selection and water quality estimation.     

Assessment of River Water Quality Based on Theory of Variable Fuzzy Sets and Fuzzy Binary Comparison Method

There has been an increasing need for the proper evaluation of river water quality in order to safeguard public health and to protect the valuable fresh water resources. In order to overcome the own limitations of the traditional evaluations which can only use a point value instead of an interval for grading standards, on the basis of the fuzzy binary comparison method (FBCM) and the theory of variable fuzzy sets (VFS), an integrated variable fuzzy evaluation model (VFEM) is proposed for the assessment of river water quality in this paper. This model possesses the preciseness of the algorithm and operability in practice, can well solve the grading standards which are interval form. In order to explore and compare the present method with other traditional methods, two cases studies in the Three Gorges and Tseng-Wen River are made. The results show that the proposed VFEM method can convey water cleanliness to certain degree by using the eigenvector of level H, which is much stricter in the superior level, and that it can improve the veracity for the assessment of water quality.     

Multi-Temporal Analysis of Mean Annual and Seasonal Stream Flow Trends,Including Periodicity and Multiple Non-Linear Regression

Global warming affects the hydrological cycle and the long-term water budget of river basins. Flow variations have been noticed in the Danube River Basin, especially in its south-western parts where a downward trend in mean annual flows has been prevalent in the past several decades. Time series of mean annual and seasonal flows of the Sava River at hydrological stations Sremska Mitrovica and Zagreb are analysed in this paper. The trend is assessed with the Mann-Kendall test including the effect of serial correlation. Additionally, the trends are assessed in the multi-temporal framework. It is concluded that the long-term periodicity of annual flows has a considerable impact on the time series trend. Long-term component with cycles of 40 years in mean annual flows are detected by the time series analysis in frequency domain. Regression analysis showed a significant correlation between mean annual flows of the Sava River and annual precipitation, mean annual atmospheric pressure and air temperatures at meteorological station Ljubljana, as well as with the North Atlantic Oscillation (NAO) Index.     

Identification of Homogeneous Rainfall Regimes in Northeast Region of India using Fuzzy Cluster Analysis

Regionalization methods are often used in hydrology for frequency analysis of floods. The hydrologically homogeneous regions should be determined using cluster analysis instead of the geographically close stations. In view of the ongoing environmental and climate changes in the Northeastern of India, regionalization of homogeneous rainfall region is essential to lay out an effective flood frequency analysis of this region. The choice of appropriate cluster approach used according to the data of the basin is also significant. In the context of this study, total precipitation data of stations operated by Indian Meteorological Department (IMD) in Northeastern of India basins for cluster analysis are used. Further, five cluster validity indices, namely Partition Coefficient, Partition Entropy, Extended Xie-Beni index, Fukuyama-Sugeno index and Kwon index have been tested to determine the effectiveness in identifying optimal partition provided by the fuzzy c mean clustering algorithm (FCM). A comparison is also performed using K- Mean clustering algorithm. Additionally, regional homogeneity tests based on l-moments approach are used to check homogeneity of regions identified by both cluster analysis approaches. It was concluded that regional homogeneity test results show that regions defined by FCM method are sufficiently homogeneous for regional frequency analysis.     

Multi-Criteria Evaluation of Small-Scale Sprinkler Irrigation Systems Using Grey Relational Analysis

The technical and socioeconomic evaluation of small-scale sprinkler irrigation systems is a multi-criteria problem characterized by complexity and uncertainty. In order to solve that, the application of Grey Relational Analysis (GRA) was presented. An evaluation model with ten sub-criteria under four groups, namely, technical, economic, environmental and social, was established. Among the criteria, calculation method of labor use in the small-scale sprinkler systems was originally addressed, and Life Cycle Cost (LCC) was used as an economic indicator. In the design of GRA, a combination weighting method based on Analytical Hierarchy Process (AHP) and entropy measurement was employed to take into account the experts’ knowledge and the inherent information in the experimental data. Six irrigation systems for three field sizes 0.5 ha, 2 ha and 5 ha respectively were considered to verify the model. The systems were optimized with Genetic Algorithms (GAs) first to figure out the optimal combinations of sprinklers and pipes and further, field tests were performed. The discussions show that: the developed approach has successfully provided the ranking of systems for three field sizes. When different types of sprinklers are used, the criteria including atomize index, application efficiency and specific energy consumption change greatly. And the ownership cost, particularly the energy consumption fee, accounts for the largest part of LCC in most of the systems. In comparison, System 5 and System 1 are generally the best. The evaluation model solved by GRA integrated with GAs is effective and can be extended to the comprehensive evaluation and optimization of other irrigation systems.     

GIS Based Estimation of Sediment Discharge and Areas of Soil Erosion and Deposition for the Torrential Lukovska River Catchment in Serbia

In the present study the SHETRAN river basin modelling system was used in conjunction with Geographic Information System (GIS) to estimate potential erosion and deposition rates within the catchment and the concentrations of sediment in a flow at the catchment outlet on the example of the 114.31 km² mountainous torrential Lukovska River catchment in Serbia. The streams in the Lukovska River catchment are short, steep and often produce hazardous torrential floods as a consequence of strong rainfall of short duration. The soil erosion and sediment discharge were analysed in view of the catchment response to physical characteristics of the catchment. Considering that the most of total annual sediment discharge in watersheds of torrential character is achieved during storm events, the SHETRAN modelling system was calibrated on the example of a storm event in 1986 and validated for three other storm events in 1974, 1976 and 1979. The simulated results of discharges and sediment concentrations at the catchment outlet for both calibration and validation events were compared with the observed data and found to be reasonable. The changes of erosion and deposition rates within the catchment and in the course of time were estimated for the calibration event in 1986. The simulated erosion rates were within the range of 1 to 10.5 t/ha and corresponded to the observed rates of erosion in Europe during extreme rain events. The presented methodology is useful in identifying the erosion vulnerable regions in a catchment where erosion control measures should be implemented.     

Selecting the Best Flood Flow Frequency Model Using Multi-Criteria Group Decision-Making

Several criteria should be considered when selecting a probability distribution to describe hydrological data. This study examines how multiple criteria can be combined to make the best selection. Selection becomes more difficult and subjective when more than two criteria are used to determine the best distribution. Under these conditions, multi-criteria decision-making is necessary. In this study, 12 distributions were tested and compared for flood frequency analysis based on five selection criteria: root mean square error, Kolmogorov-Smirnov test statistic, relative average bias, modified Anderson-Darling test, and deviation in skewness and kurtosis. The comparisons are made using a multi-criteria group decision-making (MCGDM) based on ordered weighted averaging (OWA). Two preemptive goal programming models based on variance and entropy methods for a predetermined level of optimism by a group of decision-makers, determined the weight of the OWA operator. The model was applied to a case study of Mahabad River, a major river flowing into Lake Urmia in northwestern Iran. A sensitivity analysis of the results of MCGDM was done by changing the degree of optimism of the decision-makers. The results of sensitivity analysis showed the dependence of the rankings to the optimism degrees of the decision-makers. The 3-parameter Weibull (WBL3) and Pearson type 3 (PE3) distributions had the best results for Mahabad River flood data. A Monte Carlo simulation was conducted to test the ability of the models. It was concluded from the findings of the simulation that the PE3 distribution is the most appropriate for short sample sizes, while WBL3 is preferable for larger sample sizes.     

六安市金安区农业水价综合改革实践及其成效分析

农业水价综合改革试点目标在于建立机制,采取经济措施,促进农业节水。六安市金安区作为全国农业水价综合改革试点区,提出了农业水价综合改革“七步工作法”;完善了“灌区 + 用水合作社 + 用水户”管理组织体系,培育出国家级“农民用水合作示范组织”,形成具体操作方法,其实践经验可为相关地区提供参考。     

Rapid assessment of the water–energy–food–climate nexus in six selected basins of North Africa and West Asia undergoing transitions and scarcity threats

Existing strategies for management of water scarcity in the Middle East and North Africa negotiate a complex system of trade-offs between water, energy, and food production. The effects of rural households' green water management practices on basin-level water, energy, food and carbon stocks and flows are sketched qualitatively in six basin agro-ecosystems. The case for increased strategic support for green agricultural water management practices appears stronger when weighed from the nexus perspective, rather than purely from the point of view of water balance and food production. Trade-offs under critical transitions affecting agricultural water use are explored, and the scope for quantitative monitoring is discussed.     

基于GWAS模型的武安市水资源优化配置

为缓解河北武安市水资源供需不平衡的突出矛盾,立足水资源精细化管理的需求,构建了武安市GWAS(general water allocation and simulation )模型,并开展规划年(2025年与2030年)不同情景下武安市各乡镇水资源优化配置研究。结果表明:2025年和2030年,平水情景(P=50%)下模型优化配置水量基本可以满足各乡镇水量需求,枯水情景(P=75%)下各乡镇存在不同程度的缺水情况;全市普遍农业缺水,2025年平枯情景农业缺水率分别为6.45%和44.11%,2030年平枯情景农业缺水率分别为5.05%和42.47%;优化后的供水结构改善效果显著,地下水供水量占比在各规划年平枯情景下均有所下降。