bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of Various Reanalyses Gridded Data with Observed Data from Meteorological Stations over India
Authors: Bandyopadhyay Arnab , Nengzouzam Grace , Singh W. Rahul , Hangsing Nemtinkim , Bhadra Aditi
Published: September 2018

Meteorological data such as precipitation and temperature are important for hydrological modelling. In areas where there is sparse observational data, an alternate means for obtaining information for different impact modelling and monitoring activities is provided by reanalysis products. Evaluating their behaviour is crucial to know their uncertainties. Therefore, we evaluated two reanalyses gridded data products, viz., Coordinated Regional Climate Downscaling Experiment (CORDEX) and National Centers for Environment Predictors and GCM (General Circulation Model) predictor variables (NCEP); two station based gridded data products, viz., Asian Precipitation - Highly-Resolved Observational Data Integration Towards Evaluation (APHRODITE) and India Meteorological Department (IMD) gridded data; one satellite based gridded data product i.e., Tropical Rainfall Measuring Mission (TRMM); and one merged data product, i.e., Global Precipitation Climatology Project (GPCP). These products were compared with IMD observed station data for 1971 to 2010 to evaluate their behaviour in terms of fitness by using statistical parameters such as NSE, CRM and R2. APHRODITE and TRMM gridded data showed overall good results for precipitation followed by IMD, GPCP, CORDEX and NCEP. APHRODITE also showed good agreement for mean temperature. CORDEX and NCEP gave a promising result for minimum and maximum temperatures with NCEP better than CORDEX.
Comparison Between Diffusive and Advective Approach in Quality Analysis of a Real Distribution Network
Authors: Piazza Stefania , Blokker E.J. Mirjam , Freni Gabriele , Puleo Valeria , Sambito Mariacrocetta
Published: September 2018

In recent years, the evaluation of water quality in distribution systems has generated enormous interest in the scientific community due to the increasing concentration of population in urban areas and frequent issues connected with supply water quality. Following the wave of bioterrorism subsequent the events of September 11th 2001, a need can be foreseen to seek adequate preventive measures to deal with contamination in water distribution systems that may be related to the accidental contamination and deliberate injection of toxic agents of any origin in the distribution networks. Therefore, it is very important to create a sensor system that detects contamination events in real time, while maintaining the reliability and efficiency of the measurements, limiting the cost of the instrumentation. A reliable monitoring system, for this kind of problems, cannot be deployed without realistic modelling support. The current state-of-the-art in water distribution systems analysis usually adopt a simplified approach to water quality modelling, neglecting dispersion and diffusion and considering simplified reaction kinetics. Even if such simplifications are commonly acceptable in fully turbulent flows, they may take to relevant errors in transition flows with low velocity thus taking to unreliable interpretation of the contamination in complex networks. The present paper aims to compare different modelling approaches to the evaluation of contaminant dispersion in two distribution networks: one laboratory network in which contamination experiments were carried out in a controlled environment (Enna, Italy) and a full-scale real distribution network (Zandvoort, Netherlands).
Analysing the Cascading Effects on Critical Infrastructure in Torbay Coastal/Pluvial Flooding with Climate Change
Authors: Gibson Michael , Chen Albert S , Khoury Mehdi , Vamvakeridou-Lyroudia Lydia , Stewart Dave , Wood Michael , Savic Dragan , Djordjević Slobodan
Published: September 2018

Critical Infrastructures (CIs) are commonly designed, built and maintained based on rigorous standards in order to withstand the climate and weather-related pressures. However, shifts in climate characteristics may result in increases of the magnitude and frequency of potential risks, or expose specific CI to new or increased risks not previously considered. As vital components of the normal functioning of modern societies, their resilience encompasses the operational elements, their structural integrity and the capacity to maximize business output under climate stressors. In this work, we propose an integrated and participatory methodological approach to assess the risk and enhance the resilience of interconnected CIs to urban flooding under climate change. The proposed methodology has been applied to the Torbay case study in the EU-CIRCLE project that is also presented in the paper.
Parameter Uncertainties Assessment in a Conceptual Rainfall-Runoff Model Using Bayesian Paradigm
Authors: Pereira Tatiane , Cruz Guilherme , Formiga Klebber
Published: September 2018

In this study, the calibration of the rain-flow conceptual model UFGModel1.1 is carried out, and the uncertainties in the predictions of flow rates associated with the parameter set estimates are evaluated by the Generalized Likelihood Uncertainty Estimation (GLUE) and Differential Evolution Adaptive Metropolis (DREAM). The water catchment area of the Botafogo Stream, located in the city of Goiânia, Brazil, was selected as experimental for the development of the study, in which a more distributed spatial discretisation degree (thirteen planes and six channels) was adopted for this basin. The results showed that the various parameter sets were considered optimal, allowing high modelling efficiency, despite the loss of the quality of the simulations and uncertainty increase when using the GLUE.
Two-Dimensional Modeling of Flow and Contaminant Transport in Meandering Channels
Authors: Seo Il Won , Shin Jaehyun
Published: September 2018

In this study, a depth-averaged two-dimensional hydrodynamic model and scalar transport model were used to analyze the characteristics of both velocity field and concentration field of the complex flow in meandering channels. The two-dimensional shallow water model used in this study adopted the dispersion stress method in order to induce the effect of secondary flow which is normally omitted in the depth averaging process of the shallow water equation. A new vertical profile equation for the secondary flow was applied to the momentum equations by adopting the dispersion stress method. Comparisons with the experimental results of the large meandering channels of the River Experiment Center of KICT show that the computed values of the water surface profile and velocity magnitude were in good agreement with the observed data. The results of the 2D advection-dispersion model show that the longitudinal dispersion is much larger than theoretical results by Elder (1959) in meandering channels.
Applicability of the Deep Learning Flood Forecast Model Against the Inexperienced Magnitude of Flood
Authors: Hitokoto Masayuki , Sakuraba Masaaki
Published: September 2018

Although artificial neural networks (ANN) is widely used for real-time flood prediction model, it is pointed out that the weak point of the model is poor applicability for the inexperienced magnitude of flood. In this study, the ANN models were applied to first-grade rivers in Japan, Tokoro River catchment and Abashiri River catchment. The training data of the ANN models were all the rainfall-runoff event which exceeded the Flood Watch Water Level during the period of 1998-2015. Types of observation data were river-stage and rainfall at 1-hour pitch. The validation data was the largest flood since the river-stage observation had started. The main component of the model was the four-layer feed-forward network. As a network training method, the deep learning based on the denoising autoencoder was applied. The output of the neural network was change in river-stage in T hours at the prediction point. The input data was the upstream river-stage, hourly change in river-stage and hourly rainfall. The river- stage prediction up to 6 hours showed very good accuracy, and It was proved that it can be nicely predicted even for the past largest flood.
Reservoir Monitoring Using Satellite SAR and GNSS: a Case Study in Southern Italy
Authors: Pipitone Claudia , Cigna Francesca , Dardanelli Gino , La Loggia Goffredo , Maltese Antonino , Muller Jan-Peter
Published: September 2018

Recently, it has been demonstrated that it is possible to relate water levels of a reservoir with its dam displacements. Water levels were determined via remote sensing, while dam displacements were measured via Global Navigation Satellite System (GNSS). Results have shown that displacements and water levels are correlated.

Water levels at the Magazzolo reservoir in southern Italy were firstly retrieved using two remote sensing approaches: by visual matching between the reservoir shoreline and contour lines, and by evaluating the surface extent via unsupervised classification to estimate the water levels with an area/depth relation. Dam displacements were measured using GPS receivers on the dam and a permanent station from a GNSS Continuously Operating Reference Stations (CORS) network, about 30 kilometers away.

Subsequently, two other remote sensing approaches were tested to detect reservoir levels; the first based on shape similarity indices, while the second on the evaluation of the average distance between a reservoir shoreline and contour levels. First results were extracted from a Landsat 8 optical image acquired during a clear sky day. Within this work, algorithms for water level retrieval have been tested and validated under different conditions over a more consistent satellite dataset including Sentinel-1A Synthetic Aperture Radar (SAR) images acquired from October 2014 to September 2015. The dataset is also used to analyses dam displacements via Interferometric SAR (InSAR), to be compared with the effects of water level fluctuations on the dam. First results suggest that it is possible to correlate dam displacements and water levels derived by the same dataset. However, it is shown that displacements also depend on meteorological forcing.
Framework Implementation for Smart Water Management
Authors: Ler Lian Guey , Gourbesville Philippe
Published: September 2018

The objective of smart water management is to achieve water security at all levels (building, city and regional) in a sustainability and self- sufficiency manner, through the use of information technology, monitoring and control technology and the implementation of holistic system of all the processes in water cycle. It also provides the water utilties economic benefits through the reduction of non-revenue water losses through the detection of illegal connections and water theft. According to the characteristics of smart water, we proposed the following overall framework for a smart water city. In the proposed framework, there are seven main components which can be categorized into three main compartments. First is Hardware (Sensors and Sensors Adapters) which deals data acquisition, monitoring, conversion and transmission. The second component is Water Information System (Big Water Data Management and Analysis) which deals with data processing and storage. The third one is Software (Support Services and Applications), which deals with modelling and analytics, real- time monitoring and control system, decision support system and visualization and dissemination of information to stakeholders.
Study of Pollutant Transport in Environmental Flows Using Depth-Averaged Random Walk Method
Authors: Wu Xuefei , Yang Fan , Liang Dongfang
Published: September 2018

A depth-averaged random walk scheme is applied to investigate the process of solute transport, including advection, diffusions and reaction. Firstly, the model is used to solve an instantaneous release problem in a uniform flow, for which analytical solutions exist. Its performance is examined by comparing numerical predictions with analytical solutions. The advantage of the random walk model includes high accuracy and small numerical diffusion. Extensive parametric studies are carried out to investigate the sensitivity of the predictions to the number of particles. The result reveals that the particle number influences the accuracy of the model significantly. Finally, the model is applied to track a pollutant cloud in the Thames Estuary, where the domain geometry and bed elevation are complex. The present model is free of fictitious oscillations close to sharp concentration gradients and displays encouraging efficiency and accuracy in solving the solute transport problems in a natural aquatic environment.
Application of Distributed Deterministic Hydrological Model in Mediterranean Region, Case Study in Var Catchment, France
Authors: Ma Qiang , Duong Vo Ngoc , Gourbesville Philippe
Published: September 2018

During last decade, due to intensification of urbanization, connections between human and nature become more closed. Through hydro-informatics applications, such as hydrological or hydraulic model simulations, for local water managers, their knowledge and understanding of regional hydrological characteristics can be strongly improved. Among different kinds of hydrological models, the deterministic distributed hydrological model (MIKE SHE), shows obvious advantages in integrate representing multiple hydrological processes in catchment water cycle and producing more accuracy and detail results at any places on the simulation domain. This research is in project of AquaVar, which aims to create one model-based DSS in Var catchment at French Mediterranean Region. The main objective of this study is to build one deterministic distributed hydrological model through one optimized modelling strategy, which is able to overcome to problems caused by missing data, to well represent the complicated hydrological system in Var catchment. Based on a series of hydrological assessments and model testes, under reasonable hypothesized conditions, the model of MIKE SHE was calibrated from 2008 to 2011 and validated from 2011 to 2013 with daily time interval. With high statistical performance and can well presentation of the floods occurred during simulation period, the model results is able to be applied in AquaVar DSS for real time simulation and forecasting further scenarios. Besides, the modelling strategy conceived in this research can be also applied for building deterministic distributed hydrological models in other similar area.
A Web-GIS Tool for Rainstorm Hazard Management Over Large Areas
Authors: Grasso Susanna , Libertino Andrea , Claps Pierluigi
Published: September 2018

Spatial analysis of rainfall extremes benefits of scientific advances and continuous data increments, that have led to the development of various methodologies in the last decades. In the field of the hydrologic design, due to technical, socio-economic and legislative factors, the availability of new methodologies does not imply the total substitution of the old, consolidated, procedures. This suggests that the hydrologic design is often supported by the opportunity to considering and comparing the results of estimates coming from different estimation methods. In this work, a tool named MultiRain is proposed, aimed at providing harmonized regional rainfall estimates for a given point and on areal basis. The software tool is based both on a QGis plugin and on a web-based WPS (Web Processing Service) procedure. Both the interfaces allow to build in a seamless way, from multiple models, the Intensity-Duration-Frequency (IDF) curves, either relative to a point or integrated over an area. The computation has been made automatic by manipulating old procedures lacking a map-based access. The procedures adopted for ensuring homogeneous comparison between the older ones and the more recent ones are described, with reference to three different methods and to their implementation over a 25,000km2 area in the North-West of Italy.
Doppler Radar Data Assimilation for Mesoscale Numerical Rainfall Prediction
Authors: Tian Jiyang , Liu Jia , Li Chuanzhe , Yu Fuliang
Published: September 2018

Hydrological prediction needs high-resolution and accurate rainfall information, which can be provided by mesoscale Numerical Weather Prediction (NWP) models. However, the predicted rainfall is not always satisfactory for hydrological use. The assimilation of Doppler radar observations is found to be an effective method through correcting the initial and lateral boundary conditions of the NWP model. The aim of this study is to explore an efficient way of Doppler radar data assimilation from different height layers for mesoscale numerical rainfall prediction. The Weather Research and Forecasting (WRF) model is applied to the Zijingguan catchment located in semi-humid and semi-arid area of Northern China. Three-dimensional variational data assimilation (3-DVar) technique is adopted to assimilate the Doppler radar data. Radar reflectivity and radial velocity are assimilated separately and jointly. Each type of radar data are divided into seven data sets according to the observation heights: (1) <500m; (2) <1000m; (3) <2000m; (4) 500~1000m; (5) 1000~2000m; (6) >2000m; (7) all heights. Results show that the assimilation of radar reflectivity leads to better results than radial velocity. The accuracy of the predicted rainfall deteriorates as the rise of the observation height of the assimilated radar data. Conclusions of this study provide a reference for efficient utilisation of the Doppler radar data in numerical rainfall prediction for hydrological use.
Approach to Mitigation of Territory Inundation with Help of Flood Control by Small Water Reservoirs
Authors: Ilinich Vitaly , Perminov Aleksey , Rukhovich Olga , Naumova Anna
Published: September 2018

The research dedicated to modeling of flood mitigation on the river basin with help of simulation of flood control by virtual small water reservoirs located in different places of the river system. Such problem decided with help of modeling of flood hydrograph and its routing through water reservoir on the base GIS. Reducing the degree of flooding should occur due to the limited hydraulic flow capacity of the water flow by dam spillways without flood control by people. The offered model is represented on the example of concrete river basin. Results have showed relevance of the model for flood mitigation on the river basin.
Scaling Characteristics of Storm-Centered ARF Using Radar Rainfall
Authors: Kim Eunji , Kang Boosik
Published: September 2018

In the hydraulic design practices, it is necessary to apply areal reduction factor to convert the point rainfall into the areal rainfall in the reference area. The fixed-area ARF (ARFf), which is commonly used, can be considered unrealistic because it is estimated through independent frequency analysis of the point rainfall and the areal rainfall. In this study, storm-centred ARF (ARFs) was estimated using radar rainfall data to reflect the spatial distribution characteristics of storm events effectively. ARFs representing the duration and the return period was extracted by 95% non-exceedance probability of the Weibull distribution to derive envelope covering all values from various storm events. ARFs has a correlation with not only the reference area but also the duration and the return period. Their relationships are defined as the scaling factors. A new ARFs equation that reflects the spatio-temporal characteristics of actual rainfall is presented.
Storm Surge Assessment Methodology Based on Numerical Modelling
Authors: Santos Lara , Gomes Mariana , Vieira Luis , Pinho José , Antunes Do Carmo José
Published: September 2018

Coastal zones face severe weaknesses and high-risk situations due to coastal threats like erosion and storms and due to an increasing intensive occupation. Tropical storms events can contribute to the occurrence of these situations, by causing storm surges with high water levels and, consequently, episodes of waves overtopping and coastal flooding. This work aims to describe a methodology to estimate the storm surge occurrences in the Portuguese coastal zone, recurring to historical tropical storms data that occurred in the vicinity of Portugal and to numerical modeling of its characteristics. Delft3D software together with DelfDashboard tools were applied for the numerical modelling. An automatic generation procedure of storms was implemented based on the few available historical storms data characteristics. Obtained results allows to characterize storm surges along the Portuguese coast, identifying the most vulnerable areas and, consequently contributing for its proper planning and management.
Flood Estimation in Ungauged Catchment Using ENKI Simulation: A Case Study in Norway
Authors: Chen Yueyang , Bruland Oddbjørn , Li Tiejian
Published: September 2018

This paper deals with flood estimation in ungauged catchment using continuous rainfall-runoff model. The rainfall-runoff model used in this study is developed based on the ENKI hydrological framework. In this study, flood estimation in ungauged catchment is based on transfer of parameter values from nearby station. The catchment used in this study to test the suitability of the ENKI system in flood estimation of ungauged catchment is the Gaula catchment located in Norway. This catchment has three main sub-catchments where flow records are available. The ENKI system is calibrated for each sub-catchment. In order to test its suitability in flood estimation, the average of the parameter set obtained from any of the two sub-catchments is used in the remaining sub-catchments. The performance of the ENKI system in flood estimation is evaluated in terms of the Nash–Sutcliffe (NSE) model efficiency index and the model ability to simulate the daily observed Annual Maximum Series (AMS). The result of this study shows that the ENKI framework has considerable potential in flood estimation in ungauged catchments.
Visualising the Operation of Evolutionary Algorithms Optimising Water Distribution Network Design Problems
Authors: Walker David , Craven Matthew
Published: September 2018

Multi-objective evolutionary algorithms (MOEAs) are well known for their ability to optimise the water distribution network design problem. However, their complex nature often restricts their use to algorithm experts. A method is proposed for visualising algorithm performance that will enable an engineer to compare different optimisers and select the best optimisation approach. Results show that the convergence and preservation of diversity can be shown in a simple visualisation that does not rely on in-depth MOEA experience.
A Serious Game to Explore Different Flooding Scenarios and their Respective Effects on Infrastructures
Authors: Khoury Mehdi , Chen Albert S. , Gibson Mike , Vamvakeridou-Lyroudia Lydia , Stewart Dave , Wood Michael , Savic Dragan , Djordjevic Slobodan
Published: September 2018

Using the Unity3d game engine, a Serious Game has been developed to explore different flooding scenarios under climate change in the town of Torbay in Devon, United Kingdom, and discover the resulting consequences on different critical infrastructures, aiming at enhancing their resilience. The system also sports a rather unique 3D navigable information board comprised of a virtual table populated with documents and interactive post-it notes introducing a compelling narrative.
Tapping the Power of Shallow-Water Models for Flood Hazard Mapping
Authors: Sanders Brett F. , Luke Adam , Schubert Jochen , Goodrich Kristen , Feldman David , Cheung Wing , Boudreau Danielle , Eguiarte Ana , AghaKouchak Amir , Houston Douglas , Basolo Victoria , Matthew Richard
Published: September 2018

Advances in shallow-water modeling and high performance computing, combined with the increasing availability of fine scale geospatial data, now makes it possible to simulate flooding at spatial and temporal scales comparable to how people experience flooding. This poses enormous opportunities to improve the targeted communication of flood risks and accelerate adoption of vulnerability reduction measures. Here we present collaborative shallow-water modeling of flood hazards with end users, which results in hazard maps tailored to local decision-making needs and poised to reduce flood vulnerability within at risk communities.
Numerical Simulation of the Land use Effect on Catchment Flood Mitigation
Authors: Guo Kaihua , Hou Jingming , Liu Feifei , Zhang Yangwei
Published: September 2018

Land use has significant impact on the hydrologic and hydraulic processes in a catchment. This work applies a hydrodynamic based numerical model to quantitatively investigate the land use effect on the flood patterns under various rainfall and terrain conditions in an ideal V-shaped catchment and a realistic catchment, indicating the land use could considerably affect the rainfall-flood process and such effect varies with the catchment terrain, land use scenario and the rainfall events. The rainfall-flood process is less sensitive for the side slope than the channel slope. For a channel slope lower than the critical value determined as 0.035-0.040 in this work, the forest located in the middle of the catchment slope could most effectively attenuate the flood peak. When the channel slope is higher than the critical one, forest located in the downstream of the catchment could most significantly mitigate the peak discharge. Moreover, the attenuation effect becomes more obvious as the rainfall becomes heavier. The research can help more reasonably guide the land use plan related to flood risk.
Research and Development of Flood Control Operation System of Beijing City, China
Authors: Fuxin Chai , Shu Liu , Changwei Hu , Hongping Zhang
Published: September 2018

Assembling all the data of weather, rainfall, hydrology, engineering, water logging and other real-time information and basic information of the Beijing, the flood forecasting coupling model with hydrological and hydrodynamic method and the operation model of gate and dam are constructed. Obeying object-oriented open design concept, Beijing flood control operation system based on B/S framework is developed, using Java language and database technology, which has achieved these functions that the analysis of flood control situation, flood forecast, flood control operation, flood simulation, evaluation of regulation results and scheduling management etc. At the same time, the mobile application client is developed by using html5 technology, with the functions of flood information query, mobile patrol and dangerous case report etc. All these can provide the decision-making basis for the integrated flood control management of Beijing city.
Climate Changes Impacts on Groundwater Recharge in the UAE
Authors: Mohamed Mohamed Mostafa
Published: September 2018

Despite the continuous increase in water supply from desalination plants in the UAE, groundwater remains the major source of fresh water satisfying domestic and agricultural demands. Additionally, groundwater has always been considered as a strategic water source towards groundwater security in the country. Quantification of groundwater recharge is a prerequisite for efficient and sustainable groundwater resources management in arid regions. Therefore, groundwater recharge from the ephemeral Wadi beds and subsurface flow from mountainous valley beds play an important role in water management. Although, both surface and groundwater resources in UAE are scarce; the anticipated climate change impacts could make these resources even scarcer. As such, the main aim of this paper is to assess the potential impacts of future climate variability and change on groundwater recharge in the eastern region of UAE. This paper will explore rainfall characteristics in the region, their projections and their impacts on Wadi hydrology and groundwater recharge processes. Another objective of the study is to identify groundwater recharge regions to the shallow unconfined groundwater aquifer in the northeastern part of Abu-Dhabi Emirate. Outcomes of this study will help to accurately estimate current and future sustainable extraction rates, assess groundwater availability, and identify pathways and velocity of groundwater flow as crucial information for determining the best locations for artificial recharge.
Flash Flood Simulations Based on Shallow Water Equations to Investigate Protection Measures for El Gouna, Egypt
Authors: Marafini Ester , Tügel Franziska , Özgen Ilhan , Hinkelmann Reinhard , La Rocca Michele
Published: September 2018

Severe and sudden events like flash floods are considered to be one of the most hazardous environmental disasters. Therefore, predicting the whole process of flooding is fundamental to prevent urban damages. In this context, the simulation of flash floods is an important tool to analyse the flow processes in order to find solutions to the problem. In this work, a case study of the flash flood event of 9th March 2014 in the city of El Gouna in Egypt was carried out using the Hydroinformatics Modeling System (hms), a two-dimensional (2D) shallow water model developed at the Chair of Water Resources Management and Modeling of Hydrosystems, Technische Universität Berlin. The flooding processes are simulated in great detail on unstructured grids. The aim of this work is to investigate the flow field around the settlement of the study area, when structures such as storage basins and dams are adopted as protection measures for the city. Different scenarios are analyzed to find out the most suitable one, which is able to minimize the risk during the flash flood event.
Intelligent Drought Tracking for its Use in Machine Learning: Implementation and First Results
Authors: Diaz Vitali , Corzo Perez Gerald A. , Van Lanen Henny A.J. , Solomatine Dimitri
Published: September 2018

Due to the underlying characteristics of drought, monitoring of its spatio-temporal development is difficult. Last decades, drought monitoring have been increasingly developed, however, including its spatio-temporal dynamics is still a challenge. This study proposes a method to monitor drought by tracking its spatial extent. A methodology to build drought trajectories is introduced, which is put in the framework of machine learning (ML) for drought prediction. Steps for trajectories calculation are (1) spatial areas computation, (2) centroids localization, and (3) centroids linkage. The spatio- temporal analysis performed here follows the Contiguous Drought Area (CDA) analysis. The methodology is illustrated using grid data from the Standardized Precipitation Evaporation Index (SPEI) Global Drought Monitor over India (1901-2013), as an example. Results show regions where drought with considerable coverage tend to occur, and suggest possible concurrent routes. Tracks of six of the most severe reported droughts were analysed. In all of them, areas overlap considerably over time, which suggest that drought remains in the same region for a period of time. Years with the largest drought areas were 2000 and 2002, which coincide with documented information presented. Further research is under development to setup the ML model to predict the track of drought.
Managing Large Geodatasets for Urban Flood Risk Mapping: The Mexican Flood Risk Atlas
Authors: Courty Laurent Guillaume , Breña-Naranjo Jose Agustín , Pedrozo-Acuña Adrián
Published: September 2018

We present a flood risk mapping framework created in the context of the update of the Mexican flood risk atlas. This framework is based on a nation-wide GIS database of map time-series. Those maps are used as forcing for a deterministic, raster-based numerical model. For each catchment of interest, the model retrieves the data from the GIS and perform the computation on the specified area. The results are written directly in the GIS database, which facilitate their post-processing. This methodology allows 1) the generation of flood risk maps in cities located across the national territory, without too much effort in the pre and post-processing of information and 2) a very efficient process to create new flood maps for urban areas that have not been included in the original batch.
Estimation of Longitudinal and Transverse Dispersion Coefficients in Saturated Porous Media Involving Physical Model
Authors: Ebrahimi Kumars , Nazem Mohammad Reza , Mardani Zahra , Araghinejad Shahab , Liaghat Abdolmajid
Published: September 2018

The world's urban population growth, indiscriminate use of fertilizers and chemical poisons are actually threatening groundwater resources. The main target of this paper has been tracking of distribution of a conservative tracer in a porous media and in a laboratory-scale model, to estimate the longitudinal and transverse dispersion coefficients. In this study non-cohesive sands were used to create the porous media body in the laboratory model with a grain diameter of 1-2.5 mm. Salt (NaCl) with concentrations of 5, 7.5 and 10 g/l were used as a tracer. The results of 5g/l concentration tests are reported in this paper. An EC-meter apparatus was used to measure the EC values of the tracer to monitor its plume migration. Then the collected and recorded EC data were used to calculate the tracer concentration data in different points over time, for each test. The calculated concentration data were compared with values which were obtained from the analytical solution using Fickian second law. According to the results, for instance, in the case of 5 g/l of the tracer, the obtained values of the longitudinal and transverse coefficients are equal to 3.36e-6 and 6.58e-7 m2/s, respectively.
Comparison of Accuracy of Artificial Neural Network (ANN) and Kriging Methods for Estimating Chlorine Concentration
Authors: Ghaleh Navi Faezeh , Mazandarani Zadeh Hamed , Savic Dragan
Published: September 2018

Groundwater is one of the major sources of fresh water. Maintenance and management of this vital resource is so important especially in arid and semi-arid regions. Reliable and accurate groundwater quality assessment is essential as a basic data for any groundwater management studies. The aim of this study is to compare the accuracy of two Artificial Neural Network (ANN) and Kriging methods in predicting chlorine in groundwater. In case of ANN, we created an appropriate emulator, which minimize the prediction error by changing the parameters of the neural network, including the number of layers. The best Kriging model is also obtained by changing the variogram function, such that the Gaussian variogram has the least error in interpolation of the amount of chlorine. To evaluate the accuracy of these two methods, the mean square error (MSE) and Coefficient of determination (R2) are used. The data set consists of the amount of chlorine, in a monthly basis, measured at 112 observation wells from 1999 to 2015 in aquifer Qazvin, Iran. MSE values for ANN and Kriging are 14.8 and 15.4, respectively, which indicate that the ANN has a better performance and is more capable of predicting chlorine values in comparison with Kriging.
A Teaching Experiment Using a Serious Game for WDNs Sizing
Authors: Laucelli Daniele , Berardi Luigi , Simone Antonietta , Giustolisi Orazio
Published: September 2018

A new playful interface allowing a more intuitive understanding of real-life problems is the Serious Gaming, which combines video game and utility functions addressed to problems other than the mere entertainment. The use of Serious Gaming allows having fun while favoring the learning process related to specific technical fields. This paper presents the results of using Serious Gaming within a university classroom of 26 students to solve an engineering problem, i.e. the pipe sizing of several water distribution networks. It relates to five benchmark water distribution networks, and students were asked to find the optimal value of pipe diameters to match minimum capital cost of pipes and good average pressure. Therefore, the players/students can be seen as decision makers, from a real-life standpoint. The paper has multiple aims, such as investigating the gaming approach usefulness in consolidating/learning the main concepts of network hydraulics and bringing users closer to real-life complexity of engineering problems where different technical aspects must be considered at the same time.
Development of a Modularity Index for Reliability Assessment of Isolation Valve Systems
Authors: Giustolisi Orazio
Published: September 2018

Mechanical reliability refers to the assessment of the capacity of the water distribution network (WDN) to provide a correct service to the different type of costumers under abnormal operating conditions due to a failure of a system component. It depends on the effectiveness of the isolation valve system (IVS) and on the failure probability of components. Starting from the calculation of the actual customer demands during abnormal operating conditions of the hydraulic systems due to valve shutdowns and the failure probability of the separated segments, the work develops a metric for WDN reliability assessment. The finding is that the topologic part of WDN reliability assessment, relating to the IVS, is based on the risk of disconnection. Starting from it, the works develops a special modularity index for IVS reliability assessment.
A Grid Convergence Study for the Integral Porosity Shallow Water Model on Unstructured Triangular Meshes
Authors: Özgen-Xian Ilhan , Liang Dongfang , Hinkelmann Reinhard
Published: September 2018

The integral porosity shallow water model (IP) is a modified form of the depth-averaged shallow water flow model, which utilizes porosities to account for unresolved sub-grid-scale topography such as buildings to enable fast urban flooding simulations. Existing research has repeatedly pointed out that the IP model is inherently oversensitive to the mesh de- sign. This paper presents a detailed grid convergence study of the IP model for simulating a laboratory experiment on the interaction between a dam-break wave and an obstacle in a channel, which is featured by the highly complex non-hydrostatic flow with a backwards- propagating hydraulic jump. We compare three different mesh refinement techniques with up to six levels of refinement: (1) uniform, (2) manual, (3) locally coarsened. For this investigated case, the modeling error due to the shallow water assumptions is more sig- nificant than that due to the porosity treatment. Neither a conventional shallow water model, nor the integral porosity model is able to predict the measured data well owning to non-hydrostatic flow conditions and a backwards propagating hydraulic jump. We show that the integral porosity model results converge to the conventional shallow water model results at locations that are not affected by these non-hydrostatic flow conditions. We conclude that, when the obstacle density is low, high-frequency oscillations may appear in the domain owing to Ka ́rma ́n vortex shedding. These cannot be captured accurately by the integral porosity shallow water model, unless high resolutions similar to those in the conventional shallow water models are used. However, the benefit of the porosity model is lost by using high resolutions.
AquaVar: Real Time Models for Underground and Surface Waters Management at Catchment Scale
Authors: Gourbesville Philippe , Gaetano Marc , Ma Qiang
Published: September 2018

Management of water uses requests to harmonize demands and needs which are getting more complex and sophisticated. During the past 3 decades, modeling systems for hydrology, hydraulics and water quality have been used as stand alone products and were used in order to produce an analysis of a current situation and to generate forecast according to different horizons. The current situation requests an integration of the modeling tools into the information systems that are now dedicated to the global management of urban environments. Energy distribution, water distribution, solid wastes collection, traffic optimization are today major issues for cities that are looking for functional Decisions Supports Systems (DSSs) that may operate in a sustainable perspective. The basic requirement of real time assessment of the situation, the modeling systems identified as main elements of analytics and used for forecasts have to integrate a common framework allowing modular approach and interoperability. The paper presents the interest for a generic operational approach that could be implemented in order to address the management of water uses in a complex urban environment and to provide real time assessment and forecasts. The proposed approach is illustrated with application on Var catchment (3,000 km2) located in the French Riviera.
From CCTV Data to Strategic Planning: Deterioration Modelling for Large Sewer Networks in Germany and Colombia
Authors: Caradot Nicolas , Hernandez Nathalie , Sonnenberg Hauke , Torres Andres , Rouault Pascale
Published: September 2018

Most cities are facing an aging sewer infrastructure in extensive and emerging need of repair, rehabilitation or renewal. Deterioration modelling can be a valued data mining tool to tackle this issue by supporting utilities in defining strategic investment planning. This study aims to demonstrate the benefits of deterioration modelling using sewer CCTV inspection data and GIS characteristics (material, age, depth, width, traffic load, etc.) of two different cities: Braunschweig in Germany and Bogota in Colombia. A probabilistic Markov-based model has been applied to identify and exploit relationships between sewer condition and characteristics in the extensive datasets of the two cities. The quality of prediction of the model has been evaluated by analyzing the deviation between model observations and model predictions. Results show relatively low deviations (< 15%) indicating a satisfying model performance in both cities and underlining the relevance of deterioration models to simulate the condition of sewer networks and to support strategic asset management.
A Spatio-Temporal Statistical Downscaling Approach to Deriving Extreme Rainfall IDF Relations at Ungauged Sites in the Context of Climate Change
Authors: Nguyen Truong-Huy , Nguyen Van-Thanh-Van , Nguyen Hoang-Lam
Published: September 2018

This paper proposes an efficient spatio-temporal statistical downscaling approach for estimating IDF relations at an ungauged site using daily rainfalls downscaled from global climate model (GCM) outputs. More specifically, the proposed approach involves two steps: (1) a spatial downscaling using scaling factors to transfer the daily downscaled GCM extreme rainfall projections at a regional scale to a given ungauged site and (2) a temporal downscaling using the scale-invariance GEV model to derive the distribution of sub-daily extreme rainfalls from downscaled daily rainfalls at the same location. The feasibility and accuracy of the proposed approach were evaluated based on the climate simulation outputs from 21 GCMs that have been downscaled by NASA to a regional 25-km scale for two different RCP 4.5 and 8.5 scenarios and the observed extreme rainfall data available from a network of 15 raingauges located in Ontario, Canada. The jackknife technique was used to represent the ungauged site conditions. Results based on different statistical criteria have indicated the feasibility and accuracy of the proposed approach.
A Study of Public Safety Engineering Projects for the Improvement of Drinking Water Quality in Northwestern China — an Example from Shanshan County, Xinjiang
Authors: Shao Weiwei , Liu Jiahong , Yan Denghua , Zhang Haixing , Yang Zhaohui , Yang Guiyu , Liu Fenfen
Published: September 2018

Using Shanshan County as the research focus, this study investigates drinking water safety in northwestern China and proposes measures for improving the efficiency of clean water projects targeting drinking water quality in the region. As new technologies such as the Internet and the Internet of things gain wider usage, urban and rural safe drinking water projects should focus on equipping projects, modularizing the equipment, improving project management using internetization, and developing intellectualization for increased Internet dependence. This study proposes modularization of the equipment for clean water projects for centralized and decentralized water supply programs. For management of such projects, this research proposes internetization in project management as well as intellectualization of construction, including establishment of management facilities, automation of water plant operations, intelligent control of clean water operations, and online intelligent water monitoring. This study integrates various information resources and investigates the implementation of intellectualized management of water treatment facilities through scientific advances and evaluates the potential of these approaches for increasing the quality of public service.
An Approach for Urban Catchment Model Updating
Authors: Fava Maria Clara , Mazzoleni Maurizio , Abe Narumi , Mendiono Eduardo Mario , Solomatine Dimitri
Published: September 2018

Places with limited coverage of rainfall gauges could present the challenge of providing accurate predictions, especially in cases of urbanised areas with rapid responses to heavy rainfall events. Physically-based models can represent the physics and spatial distribution of rainfall events in urban watersheds. Data assimilation techniques have been widely used in hydraulic and hydrological models to update model states and provide a more reliable prediction. However, model updating in case of non-linear systems is considerably complex. In this study, we present an approach to update an urban model assimilating water level values. The preliminary results of this study show a significant improvement in the results of simulations when assimilating water level observation. The methodology is applied in the city of São Carlos, in Brazil, where the urban system is modelled using SWMM.
Advanced Loop-flow Method for Fast Hydraulic Simulations
Authors: Vasilic Zeljko , Stanic Milos , Kapelan Zoran , Prodanovic Dusan
Published: September 2018

Solution of the nonlinear system of equations describing the network hydraulics problem can be formulated in several different manners, yielding various methods of solution. The most popular formulation is probably the Global Gradient Algorithm (GGA). Loop-flow formulation is another method revisited by number of researchers in recent years. Loop-flow method has the smaller system matrix to solve, which is a benefit over the GGA’s matrix, coming from the fact that real networks typically have far less loops than nodes. However, need for cumbersome pre-processing to identify network loops and sparsity of solution matrix, which is highly dependent of implemented loop identification algorithm, remain key drawbacks of existing loop-flow methods. In addition, systematic testing on the real life networks of different topologies and complexities is still somewhat lacking in the literature. In this paper, new loop-flow type method based on the novel TRIangulation BAsed Loop identification algorithm (TRIBAL) coupled with efficient implementation of loop-flow based hydraulic solver (ΔQ) is presented. Performance of the new TRIBAL ΔQ method based solver is tested through the comparison with the reference GGA solver. Preliminary results show that significant calculation speedups can be achieved with proposed method, maintaining prediction accuracy and convergence of the reference solver.