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Safranbolu is known for the abundance of its water resources. The city is a unique and historic settlement that hosts very beautiful examples of traditional Turkish architecture. The city attracts both national and international tourists. In this paper, firstly the Ottoman period water supply structures of Safranbolu are described. Incekaya Aqueduct and water transmission system, also known as the Pasha Water Supply System or Spring System are discussed. The Incekaya Aqueduct delivers drinking water from the spring at Danaköy Village to Safranbolu enabling the transfer over the Tokatlı Canyon via gravity. This aqueduct, a very historic and aesthetically pleasing water structure, was commissioned as a city asset by Ottoman Grand Vizier Izzet Mehmet Pasha in the period of 1794-98. The paper secondly discusses the pool rooms that serve as an example of the spatial usage of water features in traditional residential architecture of the Ottoman period in Safranbolu. The pool rooms were constructed either within or separate from the traditional Safranbolu mansions. Asmazlar Mansion in Safranbolu and Deligözler House in the Bağlar District have been evaluated as examples of pool rooms within the house, and two garden pools in the Bağlar and central districts are assessed as examples of outside pools, known as pavilion mansions with a garden pool. [ABSTRACT FROM AUTHOR]

In this paper, the problem of flooding management using hybrid model predictive control is presented and applied to the Ebro River in Spain. The Ebro River presents flooding episodes in the city of Zaragoza during spring when snow melts in the Pyrenees. To avoid flooding in populated areas, some land outside the city is prepared for flooding. This paper presents a control approach to determine and fix the level of flooding in pre-established zones by controlling side gates that determine the water input to the land to be flooded. Finally, several scenarios are used to validate the performance of the proposed approach. [ABSTRACT FROM AUTHOR]

This paper describes a novel evolutionary data-driven model (DDM) identification framework using the NSGA-II multi-objective genetic algorithm. The central concept of this paper is the employment of evolutionary computation to search for model structures among a catalog of models, while honoring the physical principles and the constitutive theories commonly used to represent the system/processes being modeled. The presented framework provides high computational efficiency through connecting a series of NSGA-II runs which share results. Furthermore, the employment of a multi- objective optimization algorithm enables a unique way of incorporating different aspects of model goodness in the model selection process, and also, at the end of the search procedure, provides a number of potential optimal model structures, making it possible for the modeler to make a choice based on the goal of the modeling. As an illustration, the framework is used for modeling wash-off and build-up of suspended solids (TSS) in highway runoff. The performance of the discovered model confirms the potential of the proposed evolutionary DDM framework for modeling environmental processes. [ABSTRACT FROM AUTHOR]

This paper presents a decision support methodology aimed at assisting Water Distribution System (WDS) operators in the timely location of pipe bursts. This will enable them to react more systematically and promptly. The information gathered from various data sources to help locate where a pipe burst might have occurred is frequently conflicting and imperfect. The methodology developed in this paper deals effectively with such information sources. The raw data collected in the field is first processed by means of several models, namely the pipe burst prediction model, the hydraulic model and the customer contacts model. The Dempster-Shafer Theory of Evidence is then used to combine the outputs of these models with the aim of increasing the certainty of determining the location of a pipe burst within a WDS. This new methodology has been applied to several semi-real case studies. The results obtained demonstrate that the method shows potential for locating the area of a pipe burst by capturing the varying credibility of the individual models based on their historical performance. [ABSTRACT FROM AUTHOR]

This paper performs a literature update of quantitative studies of water and sanitation services (WSS), with an emphasis on tracking the benchmarking literature. There are 190 studies which use cost or production functions to evaluate the performance of WSS utilities. The studies examine: (1) the scale, scope or density economies of utilities in a particular country or region; (2) the influence of ownership on efficiency; (3) the existence and power of incentives associated with different governance systems (including external regulation); and (4) performance assessment (benchmarking). In addition, this paper presents patterns regarding quantitative methods adopted over time, as well as some major trends in results. [ABSTRACT FROM AUTHOR]

Water network partitioning in district metering areas, or sectorization, is an important process for improving water network management. It can help water utilities to implement active leakage control, conduct pressure management, and prevent network contamination. It is generally achieved by closing some network pipes, thus reducing pipe redundancy and affecting system performance. No systematic set of performance indices has been defined to evaluate a sectorization design and thus allow for a comparison of different possible sectorizations on a formal basis. In this paper, several performance indices for water network partitioning are proposed and tested using two real water supply systems: Parete in Italy and Matamoros in Mexico. Both systems' sectorizations were previously designed by a novel effective automatic technique recently developed by the authors. For both the original and sectorized networks, the proposed performance indices considered energy dissipated in the network, network resilience, pressure variation, fire-fighting capacity, water age, and mechanical redundancy. Network resilience appears to be the most representative index for the entire network, whereas pressure variation indices are more appropriate for describing individual districts. Except for fire-fighting capacity in one network, system performance did not appear to be affected significantly after sectorization. [ABSTRACT FROM AUTHOR]

Considerable amounts of water can be saved by automating irrigation canals. The design of most of the practical automatic controllers rely on a simplified model of the irrigation canal. This model can be obtained from measured data (identification) or can be formulated (white box models) assuming simplifications in the physical concepts and using the canal geometry. Several models of this kind are presently available. Moreover, short canals reveal a resonance problem, due to the back and forth of waves. This paper is focused on how to choose a suitable model for short canal pools with the purpose of control design. Four simple models are applied to two different types (resonant and non-resonant) of short canals: First order transfer function based on the Hayami model, Muskingum model, Integrator Delay (ID), and Integrator Delay plus Zero (IDZ). Model predictive controllers are developed based on these models and they are tested numerically and experimentally in order to evaluate their contribution to the control effectiveness. The controllers based on the ID and IDZ model showed the best performance. [ABSTRACT FROM AUTHOR]

This paper proposes a non-negative depth reconstruction method for improving the numerical performance of a partial inertial model (PIM) for applications involving steep-slope and low-friction conditions. The PIM solves the continuity equation of two-dimensional (2D) shallow water equations (SWEs) with the interface fluxes evaluated by a simplified momentum equation that partially restores the inertial terms. In applying the PIM to flood simulations, a practical challenge is to represent complex topography and to track the moving wet-dry interface without resulting in negative water depths. Another challenge is to avoid the numerical issue caused by the lack of physical diffusive terms when it is applied to low-friction cases. To cope with these difficulties, the PIM is improved by introducing a non-negative depth reconstruction method, featuring two different ways for calculating the interface fluxes. The performance of the improved PIMs is investigated through applications to several theoretical and practical benchmark test cases. The comparison of the numerical results against analytical solutions or predictions from the original PIM and a full 2D finite-volume hydrodynamic model shows that the proposed reconstruction method can avoid non-negative water depth predictions, and improve the numerical performance of the original PIM when applied to steep-slope and low-friction conditions. [ABSTRACT FROM AUTHOR]

Multi-objective design of Water Distribution Systems (WDSs) has received considerable attention in the past. Multi-objective evolutionary algorithms (MOEAs) are popular in tackling this problem due to their ability to approach the true Pareto-optimal front (PF) in a single run. Recently, several hybrid metaheuristics based on MOEAs have been proposed and validated on test problems. Among these algorithms, AMALGAM and MOHO are two noteworthy representatives which mix their constituent algorithms in contrasting fashion. In this paper, they are employed to solve a wide range of benchmark design problems against another state-of-the-art algorithm, namely NSGA-II. The design task is formulated as a bi-objective optimisation problem taking cost and network resilience into account. The performance of three algorithms is assessed via normalised hypervolume indicator. The results demonstrate that AMALGAM is superior to MOHO and NSGA-II in terms of convergence and diversity on the networks of small-to-medium size; however, for larger networks, the performance of hybrid algorithms deteriorates as they lose their adaptive capabilities. Future improvement and/or redesign on hybrid algorithms should not only adopt the strategies of adaptive portfolios of subalgorithms and global information sharing, but also prevent the deterioration mainly caused by imbalance of constituent algorithms. [ABSTRACT FROM AUTHOR]

This paper explores the welfare costs associated with drought plan transactions between a public municipal water agency, the El Dorado Irrigation District (EID) in California in the USA and its customers. The EID imposes a tiered pricing plan for municipal customers, which was analyzed as a discrete continuous choice (DCC) model by water users within a climate driven water evaluation and planning (WEAP) model of the EID water system. The DCC is subsequently used to estimate the compensating variation (CV) measure of the loss of consumer welfare in the case where a customer does not receive water that matches a preferred level of demand. In addition to monetized welfare loss, we look at other metrics of performance such as reservoir storage and hydropower generation. For the drought-of-record under full build-out, results show that the welfare loss to EID customers from the imposed drought plan is far less than if no drought plan were in place. This suggests that current consumption is well beyond essential needs and, without a drought plan, water shortages in the later period of a drought would generate a much greater welfare loss. Most of the cost associated with the drought plan is born by EID in the form of reduced revenues. [ABSTRACT FROM AUTHOR]

In this paper, the main features and performances of a new numerical scheme, ILILPM (Improved Locally and Instantaneously Linearized Parabolic Model) are described. ILILPM is an improved version of the Parabolic and Backwater (PAB) and Linearized Parabolic Model (LPM) schemes, proposed in literature for the approximate solution of the Parabolic Wave model. The algorithm presented is able to take into account transcritical flow regime and transitions from free-surface to pressurized flow in tree-like channel networks. Due to its unconditional stability, the model allows large computational time steps, leading to very fast simulations during transients for a class of flow conditions larger than those solved by the parent schemes. The model is demonstrated by comparing its results with experimental observations and with the results provided by the numerical solution of the full De Saint-Venant equations. [ABSTRACT FROM AUTHOR]

In this paper, a time domain reflectometry (TDR)-based solution for detecting water leaks in underground pipes is described and experimentally validated. The proposed method strongly reduces the inspection time that is typically required by traditional leak detection methods. In fact, it can successfully inspect pipes that are hundreds of meters long. In this work, two different configurations of the system are described: one can be used for detecting leaks in 'already-installed' metal pipes; whereas the other is suitable to be employed for detecting leaks in 'newly-installed' pipes made of any material. The performance of both these system configurations was assessed through an extensive, on-site experimental campaign, carried out with the collaboration of one of the largest European water operators, Acquedotto Pugliese S.p.A. (AQP). Representative results, related to both configurations, of three experimental cases (ECs) are reported and commented on. Finally, some practical considerations on the applicability of the system are provided. [ABSTRACT FROM AUTHOR]

Open water systems are one of the most externally influenced systems due to their size and continuous exposure to uncertain meteorological forces. The control of systems under uncertainty is, in general, a challenging problem. In this paper, we use a stochastic programming approach to control a drainage system in which the weather forecast is modeled as a disturbance tree. Each branch of the tree corresponds to a possible disturbance realization and has a certain probability associated to it. A model predictive controller is used to optimize the expected value of the system variables taking into account the disturbance tree. This technique, tree-based model predictive control (TBMPC), is solved in a distributed fashion. In particular, we apply dual decomposition to get an optimization problem that can be solved by different agents in parallel. In addition, different possibilities are considered in order to reduce the communicational burden of the distributed algorithm without reducing the performance of the controller significantly. Finally, the performance of this technique is compared with others such as minmax or multiple MPC. [ABSTRACT FROM AUTHOR]

Computer models of water distribution networks are commonly used to simulate large systems under complex dynamic scenarios. These models normally use so-called demand-driven solvers, which determine the nodal pressures and pipe flow rates that correspond to specified nodal demands. This paper investigates the use of data parallel high performance computing (HPC) techniques to accelerate demand-driven hydraulic solvers. The sequential code of the solver implemented in the CWSNet library is analysed to understand which computational blocks contribute the most to the total computation time of a hydraulic simulation. The results obtained show that, contrary to popular belief, the linear solver is not the code block with the highest impact on the simulation time, but the pipe head loss computation. Two data parallel HPC techniques, single instruction multiple data (SlMD) operations and general purpose computation on graphics processing units (GPGPU), are used to accelerate the pipe head loss computation and linear algebra operations in new implementations of the hydraulic solver of CWSNet library. The results obtained on different network models show that the use of this techniques can improve significantly the performance of a demand-driven hydraulic solver. [ABSTRACT FROM AUTHOR]

The dissolved organic matter (DOM) plays significant role in water safety due to not only the natural occurrence but also man-induced pollution. To characterize and predict DOM treatability becomes therefore a very important and hot topic. In this paper, enhanced coagulation by four typical coagulants (FeCl3, Al2(SO4)3, polyaluminum chloride (PAC) and high performance polyaluminum chloride (HPAC)) without pH control was characterized using the chemical fractionation (resin adsorption, RA) and physical fractionation (high performance size exclusion chromatography (HPSEC) combined with peak fitting technique). The results show that the DOM removal can be separated into two stages, rapid removal and continual slow removal. The PAC exhibits efficient removal in the rapid part while the traditional salts are more efficient in the latter part. It is also very important for pH control to improve DOM removal by the traditional coagulants. DOM treatability per unit dosage (1 x 10-4 mol/l) for the four coagulants was then calculated in the order of HPAC (26.0%)>PAC (17.3%)> FeCl3 (14.3%)>Al2(SO4)3 (12.0%). Two sets of DOM treatability models, i.e. removal efficiency, for enhanced coagulation of the four coagulants were developed by combining the chemical and physical DOM fractions based on the quantitative analysis of the removal state of raw water. The two sets of models could be transformed to each other. The composition of the removable DOM by enhanced coagulation of the four coagulants was revealed and validated using 29 raw waters (in 13 source waters in three seasons), and as a result the low deviation indicated that the predicted data matched well with the actual data. It provided the possibility for the application in practical operation of water plant. [ABSTRACT FROM AUTHOR]

The research presented in this paper aims at the support tool for generation of multiple networks with preset or randomised properties. To explore particular phenomena, water distribution analysis may require a coherent set of cases. Readily available in the literature are simple synthetic networks used for benchmarking, either real-life cases that are too diverse in size and configuration. The network generation tool (NGT) developed on the principles of graph theory connects any seed of nodes prepared in EPANET modelling software, by avoiding pipe crossings or unnecessary duplications. The pipe properties can be assigned by specifying a range of arbitrary lengths and diameters, by using coordinates to calculate the lengths, or by genetic algorithm optimisation of initial diameters. Equally, the nodal elevations and demands are arbitrarily assigned when not predefined in EPANET. Several sets of networks have been generated, up to 200 junctions. To test robustness of the tool, 13,000 layouts of a 50-junction seed have been generated using different settings. NGT has been proven to be capable of executing this task mostly within a few minutes, producing network layouts that resemble those from practice. [ABSTRACT FROM AUTHOR]

The 'reclaiming' by Paris of its water back into public hands is a paradox in the homeland of transnational water companies and at a time when the European Commission rather favours the liberalisation of public services 'of general economic interest'. Yet what has happened is more complex. A quick historical review of management formulas in Europe reveals both the specific model of delegation to private companies made in France, and also the maintained direct labour management formula (with direct public procurement by municipalities) used in several French cities to be presented. Paris has a long history of public procurement of water, whilst using a private company for metering and billing customers. Mayor Chirac changed to a semi-public company with public production and private distribution contracted out to two private companies (with responsibility for the fight and left banks). Mayor Delanoë managed to reclaim the distribution in a commercial but public institution called an Établissement Public à caractère Industriel et Commercial (EPIC); this had unsuspected impacts on water supply issue in the suburbs. While Paris can obviously run its services directly, the emerging issue appears to be multi-level governance at the metropolitan level, rather than just a public-private debate. This paper also discusses in detail the arguments put forward by Anne le Strat, Deputy Mayor for Water, in favour of returning to public control, and presents the difficulties of assessing the performance of a service operator, under both delegation and direct management. [ABSTRACT FROM AUTHOR]

Nowadays irrigation district managers require several tools to assess irrigation networks' performance such as hydraulic models, geographic information systems (GIS) or decision support systems (DSS) which are available but as independent elements. Thus, simplifying the use of these tools by means of applications that integrate all these components would be helpful for irrigation district managers. In this paper, a computer tool combining a GIS, a hydraulic model and performance indicators (PIs) has been developed creating a database to deal with most information required in an irritation district. MapObjects Java Edition was used for the GIS integration and EPANET calculation module for the hydraulic modeling. This tool enables the study of the network performance, taking into account real measures (data from the remote control system) and simulated measures (obtained when running the hydraulic model) which are stored in a database and used to calculate different indicators that can be represented in the GIS. The PIs calculated with this tool give important information regarding the network response to different conditions, malfunction problems and failures in supply. Therefore, this tool is also useful to study the effects of improvements and the quality of service provided to farmers. [ABSTRACT FROM AUTHOR]

In this paper, a exible fuzzy model is proposed for the hydraulic performance analysis of separate domestic sewer systems. In the proposed model, all modeling outputs such as discharge, velocity and depth are developed as fuzzy numbers by taking into account all the available information and expert knowledge about the basic design/analysis parameters. The fuzzy outputs are then combined with performance assessment curves to calculate the hydraulic performance values. The proposed model was applied to a part of the sewer system of a city in Iran, and performance graphs were plotted. Such graphs can be used by design engineers and operation managers to improve the design quality, reliability and the performance of a system with uncertain parameters. The analysis results can also be used in decision-making and identifying priorities to develop rehabilitation strategies. [ABSTRACT FROM AUTHOR]

Performance assessment of water supply and wastewater services is today a major issue. Over the past six years, the National Civil Engineering Laboratory (Portugal) has been developing performance assessment systems for drinking water treatment plants (WTPs) and wastewater treatment plants (WWTPs). In 2009, a national field-test was launched in Portugal, 'PASt21', involving 27 plants (10 WTPs and 17 WWTPs). This paper presents an overview of the second generation of the performance indicator (PI) systems for the overall performance assessment of WTPs and WWTPs, the extent to which the systems were applied in the 5-year study period (2006--2010), and the aggregated results (average, median, percentiles 25 and 75, maximum and minimum) of representative PIs in each assessment group. It was concluded that all indicators are relevant, and the results show the ability of the proposed PI systems to assess the overall performance of a given treatment plant. The aggregated results are very important for the continuous improvement of the plant performance through benchmarking and periodic reassessment of targets. [ABSTRACT FROM AUTHOR]

The prediction of groundwater levels in a well has immense importance in the management of groundwater resources, especially in arid regions. This paper investigates the abilities of neuro-fuzzy (NF) and artificial neural network (ANN) techniques to predict the groundwater levels. Two different NF and ANN models comprise various combinations of monthly variablities, that is, air temperature, rainfall and groundwater levels in neighboring wells. The result suggests that the NF and ANN techniques are a good choice for the prediction of groundwater levels in individual wells. Also based on comparisons, it is found that the NF computing techniques have better performance than the ANN models in this case. [ABSTRACT FROM AUTHOR]

This paper describes the development of mathematical models, which represent static and dynamic properties of the AQUAI-MOD® hydraulic controller coupled with a standard pressure reducing valve (PRV) as well as a new experimental set-up for testing the controller and calibrating and validating the models. The purpose of the AQUAI-MOD® controller is to modulate the PRV outlet pressure according to the valve flow. The controller has been experimentally tested to assess its operation in different conditions and operating ranges and in all cases showed good performance. The mathematical models of the PRV and its controller have been developed and solved using the Mathematica software package to represent both steady state and dynamics conditions. The numerical results of simulation of the mathematical model have been compared with experimental data and showed a good agreement in magnitude and trends. The model can be used to simulate the behaviour of the PRV and the AQUAI-MOD® hydraulic controller in typical network applications. It can also be used at the design stage to size the controller components and to compute the required set points for the minimum and the maximum pressure before installing the controller in the field. [ABSTRACT FROM AUTHOR]

The number of automated measuring and reporting systems used in water distribution and sewer systems is dramatically increasing and, as a consequence, so is the volume of data acquired. Since real-time data is likely to contain a certain amount of anomalous values and data acquisition equipment is not perfect, it is essential to equip the SCADA (Supervisory Control and Data Acquisition) system with automatic procedures that can detect the related problems and assist the user in monitoring and managing the incoming data. A number of different anomaly detection techniques and methods exist and can be used with varying success. To improve the performance, these methods must be fine tuned according to crucial aspects of the process monitored and the contexts in which the data are classified. The aim of this paper is to explore if the data context classification and pre-processing techniques can be used to improve the anomaly detection methods, especially in fully automated systems. The methodology developed is tested on sets of real-life data, using different standard and experimental anomaly detection procedures including statistical, model-based and data-mining approaches. The results obtained clearly demonstrate the effectiveness of the suggested anomaly detection methodology. [ABSTRACT FROM AUTHOR]

There is ever increasing commercial and regulatory pressure to minimise the cost of water distribution networks even as the demand for them keeps on growing. But cost minimizing is only one of the demands placed on network design. Satisfactory networks are required to operate above a minimum level even if they experience failure of components. Reliable hydraulic performance can be achieved if sufficient redundancy is built in the network. This has given rise to various water distribution system optimization methods including genetic algorithms and other evolutionary computing methods. Evolutionary computing approaches frequently assess the suitability of enormous numbers of potential solutions for which the calculation of accurate reliability measures could be computationally prohibitive. Therefore, surrogate reliability measures are frequently used to ease the computational burden. The aim of this paper is to assess the correlation of surrogate reliability measures in relation to more accurate measures. The surrogate measures studied are statistical entropy, network resilience, resilience index and modified resilience index. The networks were simulated with the prototype software PRAAWDS that produces more realistic results for pressure-deficient water distribution systems. Statistical entropy outperformed resilience index in this study. The results also demonstrate there is a strong correlation between entropy and failure tolerance. [ABSTRACT FROM AUTHOR]