Hydrological Modeling

Enhanced streamflow forecasting has always been an important task for researchers and water resources managers. However, streamflow forecasting is often challenging owing to the complexity of hydrologic systems. The accuracy of streamflow forecasting mainly depends on the input data, especially rainfall as it constitutes the key input in transforming rainfall into runoff. This emphasizes the need for incorporating accurate rainfall input in streamflow forecasting models in order to achieve enhanced streamflow forecasting. Based on past research, it is well-known that an optimal rain gauge network is necessary to provide high quality rainfall estimates. Therefore, this study focused on the optimal design of a rain gauge network and integration of the optimal network-based rainfall input in artificial neural network (ANN) models to enhance the accuracy of streamflow forecasting. The Middle Yarra River catchment in Victoria, Australia was selected as the case study catchment, since the...

In this study, assessment of the amount of sediment inflow and the total quantity
deposited in the kenyir reservoir was made. Kenyir reservoir is the biggest man-made
lake in Southeast Asia. Kenyir dam and reservoir are mainly designed for hydroelectric
power generation and flood mitigation purposes. Recently it is observed that there is an
increase in the sediment accumulation in front of the intake particularly during low
water level in the reservoir. Prediction of sediment accumulation was undertaken by
using GSTARS3 sediment transport model. One of the main problems encountered in
employing GSTARS3 model for predicting the sediment accumulation in Kenyir
reservoir is the lack of hydrological data, so HEC-HMS is used to overcome this
problem. Statistical tests show that the modeling processes give outputs with reasonable
accuracies. The errors in the model simulation are 5.5 % for Berang river thalweg, 7.5
% for Berang river cross section, 6.2 % for Kenyir river, and 7.6 % for Kenyir river
cross section. The HEC-HMS and GSTARS3 can be used collectively to predict
sediment accumulation for reservoir with limited hydrological data.

Στόχος του παρόντος βιβλίου είναι να επικεντρωθεί στις πληροφορίες του νερού που προέρχονται από τις παρατηρήσεις της γης και τα λογισμικά, τα συστήματα και τις τεχνολογίες για τη βελτίωση της μοντελοποίησης των πληροφοριών για τους υδατικούς πόρους, την ανάλυση, την οπτικοποίηση και την κοινή χρήση τους.

Απευθύνεται κυρίως στους προπτυχιακούς και μεταπτυχιακούς φοιτητές που διδάσκονται το μάθημα της υδρογεωπληροφορικής καθώς και σε επιστήμονες που αναζητούν στοχευόμενες λύσεις στα προβλήματα της υδρολογίας, της υδραυλικής και περιβαλλοντικής μηχανικής για την αειφορική διαχείριση των υδάτων με τη χρήση μοντέλων προσομοίωσης και πληροφορικής.

Οι αναγνώστες θα εξοικειωθούν με τα μοντέλα που εφαρμόζονται σε συστήματα με βάση το νερό, θα αναπτύξουν βασικές δεξιότητες και ικανότητες στην διαχείριση των υδάτων χρησιμοποιώντας τα σημαντικότερα υδρολογικά μοντέλα αξιοποιώντας τα γεωγραφικά συστήματα πληροφοριών καθώς και διάφορα συστήματα πληροφόρησης και στήριξης αποφάσεων.

Η Υδρογεωπληροφορική προέρχεται από τη σύζευξη των 3 λέξεων: της υδρολογίας, της γης και της πληροφορικής και εύκολα καταλαβαίνει κανείς ότι αφορά ένα έντονα διεπιστημονικό πεδίο, το οποίο συνδέει το νερό και τα περιβαλλοντικά προβλήματα με διάφορες υπολογιστικές μεθόδους μοντελοποίησης και τις ραγδαία αναπτυσσόμενες τεχνολογίες της χωρικής πληροφορίας, των συστημάτων στήριξης αποφάσεων και της επικοινωνίας.

Το βιβλίο αυτό περιλαμβάνει 12 Κεφάλαια. Η ιδιαιτερότητά του είναι ότι σε κάθε κεφάλαιο πέρα από το θεωρητικό κομμάτι περιλαμβάνει αναλυτικά παραδείγματα για κάθε εφαρμογή που αποτελούν ένα πλήρη οδηγό για όποιον τα εφαρμόσει.

Το 1ο κεφάλαιο περιλαμβάνει μια εισαγωγή στην ορολογία και τους στόχους που πραγματεύεται το συγκεκριμένο βιβλίο καθώς και τους τρόπους και τα μέσα που θα χρησιμοποιηθούν προς την κατεύθυνσης της επίτευξης των συγκεκριμένων στόχων.

Το 2ο κεφάλαιο αναφέρεται στα δεδομένα (προέλευση και δομή) που χρησιμοποιούνται ως δεδομένα εισόδου (input data) προκειμένου να επιτευχθούν οι διάφορες υδρολογικές λειτουργίες.

Στο 3ο κεφάλαιο περιγράφεται η αναλυτικά η διαδικασία του ελέγχου ομοιογένειας των μετεωρολογικών δεδομένων καθώς επίσης και η συμπλήρωση και επέκταση αυτών των χρονοσειρών.

Το 4ο κεφάλαιο αποτελεί ένα λεπτομερή οδηγό δημιουργίας επιφανειών με τη χρήση των γεωγραφικών συστημάτων πληροφοριών και γεωστατικών μεθόδων δημιουργίας επιφανειών.

Το 5ο κεφάλαιο αναδεικνύει την σημαντικότητα της διακριτικής ικανότητας (ανάλυσης) και γενικά της χωρικής μεταβλητότητας της κατά τη χρησιμοποίηση της σαν δεδομένο εισόδου στις διάφορες υδρολογικές διαδικασίες.

Στο 6ο κεφάλαιο γίνεται μοντελοποίηση της εξατμισοδιαπνοής με τη χρησιμοποίηση πληροφοριακών συστημάτων.

Στο 7ο κεφάλαιο γίνεται μοντελοποίηση της διήθησης σε συνδυασμό με διάφορες διαφορικές εξισώσεις.

Στο 8ο κεφάλαιο γίνεται μια αναφορά στην υδραυλική τραχύτητα και στους τρόπους υπολογισμού της.

Στο 9ο κεφάλαιο γίνεται αναφορά στη μοντελοποίηση διάφορων υδρολογικών διαδικασιών με τη χρησιμοποίηση του εργαλείου ArcHydro και του προγράμματος ArcGIS.

Στο 10ο κεφάλαιο περιλαμβάνει μια λεπτομερή αναφορά στη μη αυτόματη υδρολογική μοντελοποίηση μέσω του προγράμματος ArcGIS σε επίπεδο λεκάνης απορροής.

Το 11ο κεφάλαιο περιλαμβάνει τη μοντελοποίηση του μοναδιαίου υδρογραφήματος με το συνδυασμό της μεθόδου του Clarke και τη χρήση των Γ.Σ.Π..

Στο 12ο κεφάλαιο παρουσιάζεται το πληροφοριακό σύστημα ολοκληρωμένης μελέτης διευθέτησης λεκανών απορροής Torrential-MIK, ένα λογισμικό που αναπτύχθηκε από το Εργαστήριο Διευθέτησης Ορεινών Υδάτων και Διαχείρισης Κινδύνου του Τμήματος Δασολογίας και Διαχείρισης Περιβάλλοντος & Φυσικών Πόρων του Δημοκρίτειου Πανεπιστημίου Θράκης, ενώ τέλος παρουσιάζονται εκτενή παραδείγματα που αφορούν το συγκεκριμένο λογισμικό.

English summary

The aim of this current book is to focus on the water information derived from the observations of the earth as long as the various software, systems and technologies to improve the modeling of information on the water resources, their analysis, visualization and their shared use.

The book addresses to all the undergraduate and graduate students who are being taught the lesson of “Hydrogeoinformatics” as long as scientists who seek for targeted solutions regarding problems that refer to hydrology, hydraulics and environmental engineering for sustainable water management using modeling
and software simulations.

Potential readers will become familiar with models applicable to systems based on water, will develop key skills as long as skills in water management using the major hydrological models, utilizing geographic information systems and various information systems and decision support systems.

Hydrogeoinformatics originates from the coupling of three words: hydrology, geo (earth) and informatics and that makes it easy for someone to understand that it refers to a strongly interdisciplinary field, which links water and environmental problems with various computational modeling methods and the rapidly developing technologies of spatial information systems, decision support systems and communication systems.

This book includes 12 chapters. Its specificity is that each chapter beyond the theoretical part includes detailed examples for each application. These examples constitute a complete guide for those who will apply the given procedures.

The 1st chapter includes an introduction to the terminology and objectives dealt within this book as well as the ways and means that are used towards the achievement of the specific targets.

The 2nd chapter refers to the data (sources and structure) that are used as input data in order to achieve the various hydrological functions.

Chapter 3 describes in detail the process of homogeneity test for the meteorological data as well as the filling and the extension of the data series.

Chapter 4 constitutes a detailed guide to create surfaces with the use of geographical information systems and surfaces generation geostationary methods.

The 5th chapter highlights the importance of the resolution and generally the spatial variability while using it as input to the various hydrological processes.

Chapter 6 analyses the modeling of the evapotranspiration using information systems, chapter 7 describes the modeling of filtration in combination with various differential equations, while chapter 8 shortly describes the method for calculation of the hydraulic roughness.

Chapter 9 refers to various hydrological modeling procedures performed by using the ArcHydro tool, an extension from ArcGIS program, while chapter 10 includes a detailed guide in manual hydrological modeling through the ArcGIS program in a basin scale.

Chapter 11 includes the modeling of the unit hydrograph combining the method of Clarke and the use of geographical information systems.

Chapter 12 presents the integrated information system for the management of waterbasins, Torrential-MIK, software that was developed from the laboratory of mountainous watersheds and risk management, department of Forestry and management of the environment and the natural resources, Democritus University of Thrace, while in the second part of this chapter detailed examples that refer to the software are presented.

Many watersheds experience scarcity of water for agricultural and domestic use for most part of the year. Ur river watershed in Tikamgarh district of Madhya Pradesh, India, falls under a drought prone region of India. Water allocation and management are essential for sustainable agriculture for this region. Water Evaluation and Planning system (WEAP)-based decision support system can prove to be an effective tool for water allocation, supply and demand analysis. In the present study, spatially distributed model by using WEAP-MABIA method has been developed for analysis and simulation of agricultural water demands in the Ur river watershed. WEAP-MABIA method uses dual crop coefficient approach which helps in computing the separate soil evaporation and transpiration under various water availability situations. Year 2012–2013 is used as base year for customizing WEAP model for 8 subwatersheds. The model was calibrated using PEST tool, available in WEAP. The calibrated model was used for estimating future water demands and unmet demands by using future climate series, from 2015 to 2030, of IPCC scenario- RCP 4.5 of GDFL-ESM2M model. As per GFDLESM2M model (RCP4.5) predictions, rainfall is going to greatly vary in the coming years. The years 2020–2021 and 2028–2029 may experience very dry climatic conditions with 500 mm or less annual rainfall, while 2017–2018, 2023–2024 and 2025–2026 may experience heavy showers (1200 mm). Straight effects of this rainfall pattern could be seen in future water availability for agriculture and resultant crop yield. A high unmet demand exists in the case of agriculture since the first priority for water supply is meant to be for domestic purpose. Area under agriculture in Ur river watershed is large, while respective water supply is low. This gap puts an extra pressure on water resources leading to over extraction of groundwater and related problems. Looking at this scenario, water allocation requires great attention to narrow down the gap between existing demands and water supply. Since area under agriculture is large, water-efficient crops should be more emphasized. Also, efficient agricultural practices and rain water harvesting should be promoted in the study area. Since the watershed falls in semiarid condition and river flows are seasonal, different stress/deficit irrigation scenarios can be built using customized WEAP model to get higher yield.

Land cover refers to the physical and biological cover over the surface of the land and it is a term used for the human modification of the earth terrestrial surface. In Ethiopia studies on land use land cover pattern and its effect was done at watershed and catchment level only. There is argument on land use land cover pattern in Ethiopia. Some researchers reported vegetation coverage was improved due to afforestation and plantation programme, while many others came up with the result of vegetation coverage was reduced in expense of agricultural land and settlement/build up area expansion. Surface runoff and evapotranspiration were affected by reduction of vegetation coverage which affects catchment hydrological cycle (increase wet river flow and decrease dry river flow).Land use land cover dynamics was reported both as causal and effect, and deforestation was the main cause of climate change in Ethiopia and also vegetation cover removal was stated as the major cause of land degradation and soil erosion which affects land productivity. More detailed study on land use land cover dynamic pattern and its effect on ecosystem at national or basin level to decide and give direction for policy makers whether it is increased or decreased when compared to before 2 or 3 decades is recommended. Also to alter the negative impact of land use land cover change on hydrological response, land degradation, soil erosion and climate change protecting existing vegetation coverage is mandatory in addition to new plantation programmes.

The  objective  of  this  research work  is  to  model  stream  flow  at the  outlet of  the  gauged  Baro watershed and analyze the associated uncertainty that can affects the accuracy in estimation of the stream flow. The soil and water assessment tool (SWAT) model was used to simulate the stream flow using the meteorological data of thirty one years from 1986 to 2016. The model was calibrated for a period of sixteen years from 1990-2005 and validated for the observed data for eleven years from 2006-2015 and shows a good agreement with R2 = 0.90 during calibration and R2= 0.93 during validation whereas NSE=0.66 during calibration and 0.61 during validation. The uncertainty analysis was done by  using  first  SUFI-2  and  to  check  parameter  uncertainty  using  SWAT-CUP,  which  are  both packages  of  SWAT  CUP,  were  used  to  establish  the  uncertainty  bounds  of  the  model
Key words;    Baro Watershed, Synthetic scenario, RCP, Climate, SWAT, SWAT-CUP

The paper presents water balance of Karup catchment, Denmark using integrated catchment modelling tool MIKE SHE. In the present study, water balance in saturated and un-saturated zone was investigated. Beside this, by changing land use water balance is simulated for Karup catchment. Unsaturated zone water balance is characterized by returning 48% water to the atmosphere as evapotranspiration, 49% as percolation and remaining 3% as un-saturated zone storage change. On the other hand, saturated zone water balance is characterized by flowing 28% water to the river as base flow, 50% as drain to river, 20% as saturated zone storage change and rest of are capillary rise and model error. Model simulation shows subsurface storage change was higher during November to February of each year. Beside this, model shows 1982 was quite dry year with low saturated zone storage.

For determining of Muskingum model coefficients, requires to an output hydrograph. Such hydrograph is not available in most rivers. In this research, the Muskingum's new coefficients are determined by the method that which is not require to output hydrograph and its accuracy is high. This coefficient is determined based on kinematic wave model with suitable scheme. The comparison between results of Muskingum model with new coefficients and dynamic wave model, showed that the new coefficients, are valid at special conditions. The new coefficients were adjusted by optimization technique for all conditions. The new adjusted coefficients are function of bed slop, bottom width and Manning's roughness coefficient for the river. The results of these coefficients were validated by dynamic wave model.

Decision makers in the field of water engineering adopt models to support their decisions. These hydrological models are simplification of reality and therefore there is always some degree of associated risk or uncertainty. Proper assessment of uncertainty in hydrological models may help to avoid high risk decisions, high cost of product-life cycle, over design structures, etc. Among uncertainty analysis techniques, methods like analytical, approximation, sampling based and methods based on analysis of model errors are the most common. In this thesis model uncertainty will be analysed using a number of different techniques.

The MIKE SHE model is able to simulate the entire stream flow which includes
direct and basic flow. Many models either do not simulate, or use simplistic
methods to determine the basic flow. The MIKE SHE model takes into account
many hydrological data. Since this study was directed towards the simulation
of surface runoff and infiltration into saturated and unsaturated zone, the
MIKE SHE is an appropriate model for reliable conclusions. In this research,
the MIKE SHE model was used to simulate runoff in the area of river basin
Sperchios. The rainfall data from meteorological stations covering the whole
river basin Sperchios were selected and used. The use of daily data entry
stations, combined with geological and soil data, primarily from the literature,
and these parameters, data and vegetation leaf area, were an important
foundation for proper calibration and simulation of all physical processes.
Overall, the model was able to simulate the surface runoff sufficiently
satisfactory, representing all the hydrological data adequately

Hydrological Hydrological Hydrological modeling tools have been increasingly used worldwide in the management of water resources at modeling tools have been increasingly used worldwide in the management of water resources at modeling tools have been increasingly used worldwide in the management of water resources at modeling tools have been increasingly used worldwide in the management of water resources at watershed watershed watershed watershed level.

A strategy for adaptive control and energetic optimization of aerobic fermentors was implemented, with both air flow and agitation speed as manipulated variables. This strategy is separable in its components: control, optimization, estimation. We optimized parameter’s estimation (from the usual KLa correlation) using sinusoidal excitation of air flow and agitation speed. We have implemented parameter’s estimation trough recursive least squares algorithm with forgetting factor. We carried separate essays on control, optimization and estimation algorithms. We carried our essays using an original computational simulation environment, with noise and delay generating facilities for data sampling and filtering.

Our results show the convergence and robustness of the estimation algorithm used, improved with use of both forgetting factor and KLa dead-band facilities. Control algorithm used in our work compares favorably with PID using the integrated area criteria for deviation between oxygen molarity and critical molarity (set point). Optimization algorithm clearly reduces energetic consumption, respecting critical molarity. Integration of control, optimization and adaptive algorithms was implemented, but future work is needed for stability. Methods were defined and implemented for stability improvement. We have implemented data acquisition and computer manipulation of air flow and agitation speed for actual fermentors.

With the objective of understanding the potential and limitations of available precipitation products for hydrological studies, this paper compares six daily and sub-daily precipitation datasets and their impacts on the water balance of the Negro River basin in the Amazon basin. The precipitation datasets contain gauge-based data [data derived from the Hybam Observatory Precipitation (HOP) dataset and provided by the Climate Prediction Center (CPC)], satellite-based data [the Global Precipitation Climatology Project (GPCP) one-degree daily and TRMM Multisatellite Precipitation Analysis (TMPA) datasets] and model-based data [the NCEP-DOE AMIP-II re-analysis (NCEP-2) and 40-year ECMWF Re-Analysis (ERA-40) datasets]. Each dataset has a common set of meteorological forcing data which are used to run the MGB-IPH hydrological model for the period from January 1998 to August 2002.The average precipitation of all the datasets is 2542 mm for the Negro River basin, with a standard deviation of 317 mm. TMPA and NCEP-2 have the lowest (2216 mm/year) and the highest (3065 mm/year) precipitation rates, respectively. The HOP and CPC datasets agree best with observed discharge. GPCP gives the best results among the ungauged datasets, followed by ERA-40. TMPA and NCEP-2 are found to be the least accurate. TMPA can reproduce the water cycles reasonably well, but underestimates the precipitation fields and discharges over the basin, while NCEP-2 is unable to represent the rainfall quantity and cycles, and the water discharge. Results suggest that gauge-based data are still the most representative of the actual precipitation in the northern Amazon basin. However, some satellite and model-based can reproduce fairly well the water cycle at the basin scale and monthly time step.► The spatio-temporal heterogeneities of six precipitation at the daily time step over the Negro River basin were compared. ► The effects of the datasets on the simulated water cycle of the Negro River basin were analyzed by using the MGB-IPH model. ►The rainfall datasets were compared at different temporal scales and also at the basin-wide and catchment scales. ► Mean rainfall over the basin varied substantially from a dataset to another but the evapotranspiration is in good agreement. ► This reveals an energy limited evapotranspiration in most parts of the basin.

La microcuenca de drenaje de la quebrada Curucutí se ubica en la vertiente norte del Macizo del Ávila (10º33’08”-10º36’23” LN y 66º57’38”-66º59’14” LO), en el sector centro occidental del estado Vargas (Venezuela). Este pequeño sistema fue una de las más de veinte cuencas que se activaron hidromorfodinámicamente, como respuesta a las excepcionales precipitaciones ocurridas en Diciembre de 1999, en el Litoral Central de Venezuela. Es por ello que el propósito de este trabajo es, analizar e interpretar la dinámica hidrogeomorfológica de la microcuenca de drenaje de la quebrada Curucutí, en términos del control que ejercen sus parámetros morfométricos en las características de la respuesta hidrológica. La metodología comprendió: (a) Cálculos y mediciones de parámetros morfométricos de la microcuenca y de su red de drenaje, con apoyo en cartas topográficas del área a escalas 1:5.000 y 1:10.000, y ortofotomapa a escala 1:25.000; (b) cálculo del tiempo de concentración de la microcuenca, y de la velocidad media del flujo; y (c) estimación de los hidrogramas unitarios y caudales pico de crecientes. También se realizó un trabajo de campo, para medir el ancho de la sección hidráulica de interés (ápice del abanico). La microcuenca de drenaje de la quebrada Curucutí, es un sistema hidrogeomorfológico cuya respuesta hidrológica está determinada por la pequeña área del mismo, fuertes pendientes en las vertientes y cauces del sector montañoso, la densidad de drenaje media, el orden 5 de la microcuenca, una relación de bifurcación media de 3,73, alta torrencialidad, las dimensiones de las tormentas y la intensidad y duración de las lluvias. En breves palabras, la respuesta hidrológica de la microcuenca, es condicionada y controlada por las características morfométricas del sistema y de su red de drenaje. Los cortos tiempos de concentración, así como las magnitudes estimadas de los caudales pico de crecientes y los picos y tiempos al pico de los hidrogramas unitarios obtenidos, corroboran la influencia que ejercen las características fisiográficas de la microcuenca y la estructura de la red de drenaje, en las respuestas rápidas y violentas del sistema. Ello definen escenarios críticos de inundaciones, para eventos de períodos de retorno de 50, 100 y 500 años principalmente, y en el peor de los casos de 1000 años. Este trabajo aporta elementos de gran importancia para la concepción y/o reevaluación de ser el caso, del diseño hidráulico e hidrológico de estructuras para el control de crecientes y de sedimentos, así como para el análisis, evaluación y zonificación de la amenaza por inundaciones, y el diseño de sistemas de alertas tempranas.

In modern civilization, water distribution network has a substantial role in preserving the desired living standard. It has different components such as pipe, pump, and control valve to convey water from the supply source to the consumer withdrawal points. Among these elements, optimal sizing of pipes has great importance because more than 70% of the project cost is incurred on it. Unfortunately, optimal pipe sizing falls in the category of nonlinear polynomial time hard (NP-hard) problems. Hence, solid research activities march on because of two facts, namely, importance and complexity of the problem. The literature revealed that the stochastic optimization algorithms are successful in exploring the combination of least-cost pipe diameters from the commercially available discrete diameter set, but with the expense of significant computational effort. The hybrid model PSO-GA, presented in this paper aimed to effectively utilize local and global search capabilities of particle swarm optimization (PSO) and genetic algorithm (GA), respectively, to reduce the computational burden. The analyses on different water distribution networks uncover that the proposed hybrid model is capable of exploring the optimal combination of pipe diameters with minimal computational effort.

Utilizing new approaches to accurately predict groundwater level (GWL) in arid regions is of vital importance. In this study, support vector regression (SVR), Gaussian process regression (GPR), and their combination with wavelet transformation (named wavelet-support vector regression (W-SVR) and wavelet-Gaussian process regression (W-GPR)) are used to forecast groundwater level in Semnan plain (arid area) for the next month. Three different wavelet transformations, namely Haar, db4, and Symlet, are tested. Four statistical metrics, namely root mean square error (RMSE), mean absolute percentage error (MAPE), coefficient of determination (R 2), and Nah-Sutcliffe efficiency (NS), are used to evaluate performance of different methods. The results reveal that SVR with RMSE of 0.04790 (m), MAPE of 0.00199%, R 2 of 0.99995, and NS of 0.99988 significantly outperforms GPR with RMSE of 0.55439 (m), MAPE of 0.04363%, R2 of 0.99264, and NS of 0.98413. Besides, the hybrid W-GPR-1 model (i.e. GPR with Harr wavelet) remarkably improves the accuracy of GWL prediction compared to GPR. Finally, the hybrid W-SVR-3 model (i.e. SVR with Symlet) provides the best GWL prediction with RMSE, MAPE, R2, and NS of 0.01290 (m), 0.00079%, 0.99999, and 0.99999, respectively. Overall, the findings indicate that hybrid models can accurately predict GWL in arid regions.

Urban flooding, caused by unusually intense rainfall and failure of storm water drainage, has become more frequent and severe in many cities around the world. Most of the earlier studies focused on overland flooding caused by intense rainfall, with little attention given to floods caused by failures of the drainage system. However, the drainage system contributions to flood vulnerability have increased over time as they aged and became inadequate to handle the design floods. Adaption of the drainages for such vulnerability requires a quantitative assessment of their contribution to flood levels and spatial extent during and after flooding events. Here, we couple the one-dimensional Storm Water Management Model (SWMM) to a new flood inundation and recession model (namely FIRM) to characterize the spatial extent and depth of manhole flooding and recession. The manhole overflow from the SWMM model and a fine-resolution elevation map are applied as inputs in FIRM to delineate the spatial extent and depth of flooding during and aftermath of a storm event. The model is tested for two manhole flooding events in the City of Edmonds in Washington, USA. Our two case studies show reasonable match between the observed and modeled flood spatial extents and highlight the importance of considering manholes in urban flood simulations.

ABSTRAK Hubungan curah hujan-limpasan merupakan fenomena hidrologi yang kompleks, sehubungan dengan adanya proses yang tidak linier, bervariasi terhadap waktu dan merupakan distribusi yang spasial. Hubungan curah hujan limpasan ini sangat penting artinya dalam bidang manajemen sumber daya air. Dengan mengetahui data hujan di stasiun – stasiun penakar hujan yang berpengaruh pada DAS yang ditinjau, maka dapat dicari hubungan antar hujan yang jatuh dan limpasan aliran yang terjadi. Penelitian ini disusun untuk pengaplikasian model dalam mentransformasikan curah hujan limpasan menjadi debit aliran sungai. Model Hidrograf Regresi Linier adalah metode yang digunakan untuk menentukan fungsi linier yang paling sesuai dengan kumpulan titik data (curah hujan dan debit) yang diketahui dengan menggunakan persamaan yang sudah ditentukan untuk memberikan hasil perbandingan simulasi dengan data aktual. Model Tangki adalah salah satu model hidrologi yang gunanya untuk menganalisis karakteristik aliran sungai dimana dalam hal ini adalah limpasan air sungai yang terjadi. Model ini menerima masukan data harian hujan, evapotranspirasi dan debit sungai dalam satuan mm/hari sebagai parameter tank model. Data yang diperoleh dari 3 stasiun air hujan yaitu di Tampaksiring, Tegalalang dan Ubud sehingga didapat hasil rata-rata dengan metode Polygon Thiessen yang dikombinasi dengan data debit dan Evapotranspirasi. Penyusunan Hidrograf Regresi Linier dengan menggunakan sebaran titik-titik data dari hasil pengukuran pada bidang x-y didapat rumus persamaan dengan y=8.2678x+0.5878, dimana (y) debit simulasi dan (x) intensitas curah hujan dan penyusunan tangki pada DAS Tukad Petanu WS 03-01.A3.223 di daerah hilir merupakan daerah persawahan. Secara umum, daerah persawahan memiliki tanah keras dan memiliki 2 Model Tangki dalam Parameternya. Hasil pengamatan untuk Hidrograf Regresi Linier dengan nilai koefesien korelasi (r) dari tahun 1994 sebesar 0.92, tahun 1995 s/d 1998 nilai (r) tidak diketahui ini disebabkan karena adanya data observasi yang tidak akurat, dengan menunjukkan data yang bisa dipakai untuk mendekati dengan data observasi adalah tahun 1994. Dan untuk Model Tangki nilai koefesien korelasi (r) tahun 1994 sebesar 0.97, tahun 1997 sebesar 0.62, dan tahun 1995, 1996, dan 1998 nilai (r) tidak diketahui ini disebabkan juga data observasi yang tidak akurat, dan hasilnya menunjukkan data yang bisa dipakai untuk mendekati dengan data observasi adalah tahun 1994 dan 1997. Dengan kata lain untuk rata-rata nilai (r) Hidrograf Regresi Linier sebesar 0.18 dari tahun (1994 s/d 1998) dan Model Tangki sebesar 0.32 dari tahun (1994 s/d 1998). ini menunjukkan bahwa model tangki lebih bisa diterima dalam menghasilkan data debit permodelan. Karena model Tangki memiliki data input masukan yang lebih banyak dari pada model Hidrograf Regresi Linier. Kata kunci: Curah Hujan Limpasan, Hidrograf Regresi Linier, Model Tangki.

Para la estimación de caudales picos de crecientes como parte de la investigación que se lleva a acabo a través del Proyecto “Hidrogeomorfología de cuencas de drenaje de la vertiente norte del Macizo del Ávila, estado Vargas, Venezuela”, se procedió a calibrar el Modelo del HUIG en la microcuenca de drenaje de la quebrada Curucutí. Esta microcuenca se ubica en el sector centro occidental del estado Vargas al norte de Venezuela, y su localización geoastronómica está definida por las coordenadas: 10º33’08” – 10º36’23” LN y 66º57’38” – 66º59’14” LO. Para la aplicación del modelo del HUIG, se ejecutaron tres etapas fundamentales concatenadas en el siguiente orden: (a) cálculo de los hietogramas de exceso de lluvia a partir de los hietogramas de diseño suministrados para la investigación; (b) cálculo de intensidades de la lluvia efectiva; y (c) estimación propiamente dicha de los caudales picos de crecientes. La calibración del modelo en la microcuenca de drenaje de la quebrada Curucutí, dependió de los siguientes parámetros: (a) el número adimensional de curva CN, utilizado para el cálculo de los hietogramas de exceso de lluvia; (b) los parámetros morfométricos de la cuenca (pendiente media (S) de la corriente de orden más alto; ancho máximo del cauce (b) de la corriente de orden más alto en la sección hidráulica de interés; longitud total (L) de la corriente de orden más alto; área de drenaje (A) de la corriente de orden más alto hasta la sección hidráulica de interés; relación de longitud media (RL) de la red de drenaje hasta la sección hidráulica de interés) utilizados en el cálculo de las caudales picos de crecientes; y (c) la n (coeficiente de rugosidad del lecho de la quebrada) de Manning, el cual es un parámetro hidráulico que se utilizó también en el cálculo de las caudales picos de crecientes. Los caudales obtenidos para distintos períodos de retorno (2,33, 5, 10, 25, 50, 100, 500 y 1000 años) y duraciones de la lluvia a intervalos de 5 minutos durante 24 horas, se compararon estadísticamente con los obtenidos por González y Córdova (2003) para la misma microcuenca, por el método de la onda cinemática. Los coeficientes de correlación arrojaron muy buenas aproximaciones, con lo que se afirma que la calibración estuvo bastante ajustada. Ello permitirá aplicar este modelo calibrado a otras cuencas de drenaje con características fisiográficas similares, e información hidrológica escasa o inexistente.

Hydrological droughts usually affect large areas and minimum river flow is an appropriate index for the study of hydrological droughts. are commonly used for analyzing multivariate data? This study considered 35 hydrological indicators which were divided into 5 groups, including amplitude, duration, frequency, timing, variability, that characterized the various flow regime characteristics. Factor analysis and principal component analysis were used to calculate the hydrological indices for 14 stations of Karun watershed, Iran, and analyze the main components (PCAs). Then, the main components, the most important parameters of the Karun domain, which included A2, A4, D3, D5, V1, F and T, were determined and based on these indices, they were grouped by cluster analysis. Hydrological indicators were divided 6 groups which most of them near PC1 which then follow PC2 but at least of them follow other PC. The only group has positive axis include: D6, A2, A1 that Station 7 and 13 near it. Three groups hydrological indicators have positive PC2 and one group also negative and positive PC2.two groups has negative PC2.two groups of hydrological indicators has positive and 4 groups of hydrological indicators has negative.

Keywords:
Cluster Analysis, Component Analysis, Hydrological Drought, Hydrological Index

1] Accurate estimates of basin-wide water and energy cycles are essential for improving the integrated water resources management (IWRM), especially for relatively dry conditions. This study aims to evaluate and apply a fine-resolution global data set (Global Land Data Assimilation System with Noah Land Surface Model, GLDAS/Noah; 3-h, 0.25-degree) in a semiarid mesoscale basin (∼15000 km 2 ). Four supporting objectives are proposed: (1) validating a Water and Energy Budget-based Distributed Hydrological Model (WEB-DHM) for GLDAS/Noah evaluation and application; (2) evaluating GLDAS forcing data (precipitation; near-surface air temperature, T air ; downward shortwave radiation, R sw,d ; downward longwave radiation, R lw,d ); (3) investigating GLDAS/Noah outputs (land surface temperature, LST; evapotranspiration; fluxes); (4) evaluating the applicability of GLDAS forcing in modeling basin-wide water cycles. Japanese 25-year reanalysis and in situ observations (precipitation; T air ; R sw,d ; discharge) are used for GLDAS/Noah evaluation. Main results include: (1) WEB-DHM can reproduce daily discharge, 8-day LST and monthly surface soil moisture (point scale) fairly well; (2) the GLDAS is of high quality for daily and monthly precipitation, T air , monthly R lw,d , while it overestimates monthly R sw,d ; (3) the GLDAS/Noah agrees well with the verified WEB-DHM and JRA-25 in terms of LST, upward shortwave and longwave radiation. While the net radiation, evapotranspiration, latent and sensible heat fluxes modeled by GLDAS/Noah are larger than WEB-DHM and JRA-25 simulations in wet seasons; (4) the basin-integrated discharges and evapotranspiration can be reproduced reasonably well by WEB-DHM fed with GLDAS forcing except linear corrections of R sw,d . These findings would benefit the IWRM in ungauged or poorly gauged river basins around the world. (2011), Evaluation and application of a fineresolution global data set in a semiarid mesoscale river basin with a distributed biosphere hydrological model,

Successful streamflow forecasts depend on an adequate performance evaluation of the hydrological model. In this study, the hydrological responses were compared using two hydrological models, physic-based and semi-distributed, Soil and Water Assessment Tool (SWAT) and Variable Infiltration Capacity (VIC), using input data from the Verde River Watershed, located in the Minas Gerais state in southern Brazil. This is a study of one of the most important headwater watershed regions of Brazil (Mantiqueira Range). Both models were suitable for streamflow simulation, with values of R2 (determination coefficient) and NSE (Nash-Sutcliffe) higher than 0.8, NSELog higher than 0.35 (Nash–Sutcliffe Efficiency of the logarithmic values of discharge) and PBIAS (percentage deviation) less than 25%. The integration of SWAT and VIC models can be useful in different water-resource assessment studies. Therefore, based upon this study further investigations should be conducted using various hydrological ...

Simulation of large basins (over 1,000 km2) is needed for largescale water resources planning and management. Due to increased volume of calculations and increased heterogeneity, basin simulation is challenging. In areas with severe withdrawal of water resources, simulating and having the ability to predict future changes is important, while severe withdrawals complicate issues and simulation. The aim of this study is to evaluate the ability of Hydro Geosphere, a fully integrated hydrologic model, to simulate a large basin (Hamadan-Bahar Catchment, Iran) with an area of 2,456 km2 and severe groundwater withdrawals. In this study, fully-integrated surface/ subsurface flow modeling was done using the Hydro Geosphere model. Simultaneous solution of surface and groundwater flow equations and
calculation of actual evapotranspiration as a function of soil moisture in each unit of evaporation zone improves the simulation of interdependent processes such as aquifer recharge and drainage, which is one of the difficult issues in modeling. To obtain initial conditions, the model was used in steady state mode using 20-year average of rainfall data and withdrawal from the aquifer. Then, to apply the model in unsteady state and evaluate its performance in daily stresses, the model was used for the period of 19922005 and parameters were calibrated. Validation was done for the period of 2006-2010 and results showed satisfactory hydrologic simulation of the study area.

The main objective of this study is to take advantage of spatial altimetry data to help monitoring river discharges in poorly gauged basins. A methodology is defined to obtain high accuracy relationships between water levels provided by spatial altimetry and water discharge computed by a hydrological model. The proposed method is based on a distributed rainfall-runoff model calibrated and validated against a few in situ data. Discharge is modeled in a daily time step at river locations tracked by the satellite and combined with water height observations to produce rating curves. The methodology is evaluated in the Northern Amazon basin, corresponding to the upper part of the Branco River basin, the major tributary of the Negro River. The MGB-IPH (an acronym from the Portuguese for Large Basins Model and Institute of Hydraulic Research) is run for a 10-year period, from January 1997 to December 2006, in a daily time step. Eight gauge stations are used to calibrate and validate the model, resulting in Nash-Sutcliffe coefficients from 0.47 (Maloca do Contão station -5896 km 2 ) to 0.85 (Caracaraí station -126,085 km 2 ) in the calibration process, and 0.42 (Posto Funai station -9708 km 2 ) to 0.94 (also at Caracaraí station) in the validation process. Results suggest the existence of relations between model accuracy and the size of drainage areas, which can be firstly attributed to a poor rainfall monitoring and also to model restrictions, which was specially developed to large basins. Water level time series (35-day time step) at 12 virtual stations (VS) are deduced from ENVISAT tracks from October 2002 to November 2006. The rating curve parameters, including the zero-flow depth (h), are estimated by fitting a power-law relation between modeled discharges and satellite-derived water altimetry. Zero-flow depths are optimized for each VS in order to define the best fitted curve. Additionally, slopes along reaches where two or more VS's are defined can be provided. Comparisons between daily water discharges provided by in situ observations and rating curve estimates at three VS's resulted in RMS errors from 9.9% to 26.9%, which are in accordance with previous experiences and acceptable for most hydrological applications. River bed slopes derived from both ENVISAT and SRTM were compared. Results suggest that altimetric data provide more accurate slopes and it should be preferred whenever it is available.

Groundwater is the main available freshwater resource and therefore its use, management and sustainability are closely related to the Sustainable Development Goals (SDGs). However, Land Use Land Cover (LULC) and climate change are among the factors impacting groundwater recharge. The use of land-use and climate data in conjunction with hydrological models are valuable tools for assessing these impacts on river basins. This systematic review aimed at assessing the integrated modeling approach for evaluating hydrological processes and groundwater recharge based on LULC and climate change. The analysis is based on 200 peer-reviewed articles indexed in Scopus, and the Web of Science. Continuous research and the development of context-specific groundwater recharge models are essential to increase the long-term viability of water resources in any basin. The long-term impacts of natural and anthropogenic drivers on river basin interactions require integrating knowledge and modeling capabilities across biophysical responses, environmental problems, policies, economics, social, and data.

Rapid glacier retreats due to rising temperatures have been predicted in the Hindukush-Karakoram-Himalaya (HKKH). Recent findings indicate shrinking glaciers in parts of the Himalayas, affecting ice storage and ultimately water availability. Insights on ice storage of the HKKH remain controversial, where glaciers retreat in some parts, while surging in others. In high-altitude areas only few in-situ observations are available, leading to ambiguous closure of the hydrological balance. Objective of this paper is to analyze the closure for the Upper Indus Basin (UIB). A first-order analysis using longterm flow and precipitation records, estimates of evaporation and ice storage is performed. Satellite information, atmospheric reanalyses, in-situ observations and related uncertainty are independently investigated. Trend analysis of 50-year stream flow indicates a statistically insignificant decrease of basin outflow. Analysis of 100-year precipitation data at valley stations shows no significant longterm trend, whereas temperature has increased moderately. Estimates of evaporation and sublimation in the HKKH system are notably few. Findings suggest that a substantial loss of ice in the UIB during the 1999-2009 decade is unlikely. Ice storage is probably at equilibrium or under slight accumulation, as indicated by recent altimetry studies in the Karakoram. In the UIB there is no evidence for intermediate-term risk to water supply as suggested in recent literature.

The Merguellil catchment (1183 km), whose runoff is a major water resource for the Kairouan area in semi-arid Tunisia, was equipped with water and soil conservation works (WSCW) during the 1990s, mainly to reduce soil erosion and silting of the downstream El Haouareb reservoir. The spatial configuration of the hydro-meteorological station network makes it possible to characterize the catchment-scale hydrological impact of the WSCW. The catchment is subdivided into two parts, the upper subcatchment and the lower subarea. The latter covers 84% of the catchment surface area and gathers 97% of the surfaces controlled by WSCW. The space-time variability of the rainfall-runoff relationship is first analysed, comparing the runoff responses from the two nested catchments for different rain event depth ranges. A non-parametric test, based on a resampling approach, is applied to the lower subarea runoff simulated with the GR4J daily lumped rainfall-runoff model, which is calibrated for severa...

Successful streamflow forecasts depend on an adequate performance evaluation of the hydrological model. In this study, the hydrological responses were compared using two hydrological models, physic-based and semi-distributed, Soil and Water Assessment Tool (SWAT) and Variable Infiltration Capacity (VIC), using input data from the Verde River Watershed, located in the Minas Gerais state in southern Brazil. This is a study of one of the most important headwater watershed regions of Brazil (Mantiqueira Range). Both models were suitable for streamflow simulation, with values of R2 (determination coefficient) and NSE (Nash-Sutcliffe) higher than 0.8, NSELog higher than 0.35 (Nash–Sutcliffe Efficiency of the logarithmic values of discharge) and PBIAS (percentage deviation) less than 25%. The integration of SWAT and VIC models can be useful in different water-resource assessment studies. Therefore, based upon this study further investigations should be conducted using various hydrological ...

GA SAKe is an empirical-hydrological model aimed at forecasting the time of occurrence of landslides. Activations can be predicted of either single landslides or sets of slope movements of the same type in a homogeneous environment. The model requires a rainfall series and a set of dates of landslide activation as input data. Calibration is performed through genetic algorithms, and allows for determining a family of optimal kernels to weight antecedent rainfall properly. As output, the mobility function highlights critical conditions of slope stability. Based on suitable calibration and validation samples of activation dates, the model represents a useful tool to be integrated in early-warning systems for geo-hydrological risk mitigation purposes. In the present paper, examples of application to three rock slides in Calabria and to cases of soil slips in Campania are discussed. Calibration and validation are discussed, based on independent datasets. Obtained results are either excellent for two of the Calabrian rock slides or just promising for the remaining case studies. The best performances of the model take advantage of an accurate knowledge of the activation history of the landslides, and a proper hydrological characterization of the sites. For such cases, GA SAKe could be usefully employed within early-warning systems for geo-hydrological risk mitigation and Civil Protection purposes. Finally, a new release of the model is presently under test: its innovative features are briefly presented.