Esse trabalho identificou, testou e aprimorou modelos de propagação de vazão simplificados a fim de verificar as vantagens e desvantagens dos modelos. As soluções apresentadas por esses modelos foram testadas com um modelo hidrodinâmico completo, considerado nesse trabalho como resultados ideias. Os modelos hidrodinâmicos simplificados testados foram: Um modelo não linear de Onda Cinemática, o modelo Muskingum-Cunge linear, duas versões do modelo Muskingum-Cunge não linar, o modelo Muskingum-Cunge modificado por Todini e o modelo IPHS1. O modelo hidrodinâmico completo utilizado nesse trabalho foi o modelo HEC-RAS. Desenvolveu-se ainda uma metodologia para representar o efeito da planície de inundação. Essa metodologia foi implementada nos modelos hidrodinâmicos simplificados. Para avaliar o comportamento dos diferentes modelos de propagação disponíveis foram criados testes numéricos em que foram aplicados os diferentes modelos, com variação de características dos hidrogramas sintético de entrada, das características do leito do rio e da planície de inundação, e dos critérios de discretização temporal e espacial. A avaliação dos resultados foi feita através dos erros de conservação de volume, de vazão de pico e de tempo de ocorrência da vazão de pico. Além disso, também foram considerados, em alguns testes, os critérios de aplicabilidade de Ponce para onda cinemática e difusão além da formulação do Δx ideal proposto por Fread. Os resultados mostram que o modelo Muskingum-Cunge Todini, modificado para representar o efeito da planície de inundação, é muito promissor. Esse modelo apresentou resultados que se aproximaram muito dos resultados obtidos pelo HEC-RAS, enquanto os outros modelos hidrodinâmicos simplificados apresentaram resultados piores. Com relação aos critérios de aplicabilidade, recomenda-se o uso de um Δx três vezes menor do que o valor sugerido por Fread. Além disso, pode-se concluir que os modelos simplificados podem ser utilizados fora dos limites de aplicabilidade sugeridos por Ponce. / This work has identified, tested and improved simplified flood routing models to verify the advantages and disadvantages presented. The solutions provided by these models were tested by using a full hydrodynamic model considered in this work as an ideal result. The simplified hydrodynamic models used were: A variable parameter kinematics wave model, the Muskingum-Cunge flood routing model, the variable parameter Muskingum-Cunge flood routing model (three and four points scheme) the Muskingum-Cunge modified by Todini (MCT) and the model IPHS1. The full hydrodynamic model used was HEC-RAS. It was also proposed a procedure to represent the effect of the floodplain rivers. To evaluate the behavior of different flood routing models numerical tests were created and were applied to then. The characteristics of synthetic inflow hydrographs, the characteristics of riverbed and floodplain, and the criteria for temporal and spatial discretization were perturbed. The evaluation of the results was made through the errors of conservation of volume, peak flow and time of occurrence of peak flow. Moreover, it was also considered, in some tests, applicability criteria recommended by some authors for different models, such as models of kinematic flood wave and diffusive flood wave. The results show that the Muskingum Cunge Todini, modified to represent the effect of the floodplain flow is very promising. Finally, it is also shown that this model closely approaches the full Saint Venant equation solution (HEC-RAS). The others models were worse than HEC-RAS and MCT. About applicability criteria, it recommends the use of the Δx three times smaller than the value suggested by Fread. Moreover, the simplified hydrodynamic models can be used outside limits of applicability suggested by Ponce about kinematic and diffusive wave.

Esse trabalho identificou, testou e aprimorou modelos de propagação de vazão simplificados a fim de verificar as vantagens e desvantagens dos modelos. As soluções apresentadas por esses modelos foram testadas com um modelo hidrodinâmico completo, considerado nesse trabalho como resultados ideias. Os modelos hidrodinâmicos simplificados testados foram: Um modelo não linear de Onda Cinemática, o modelo Muskingum-Cunge linear, duas versões do modelo Muskingum-Cunge não linar, o modelo Muskingum-Cunge modificado por Todini e o modelo IPHS1. O modelo hidrodinâmico completo utilizado nesse trabalho foi o modelo HEC-RAS. Desenvolveu-se ainda uma metodologia para representar o efeito da planície de inundação. Essa metodologia foi implementada nos modelos hidrodinâmicos simplificados. Para avaliar o comportamento dos diferentes modelos de propagação disponíveis foram criados testes numéricos em que foram aplicados os diferentes modelos, com variação de características dos hidrogramas sintético de entrada, das características do leito do rio e da planície de inundação, e dos critérios de discretização temporal e espacial. A avaliação dos resultados foi feita através dos erros de conservação de volume, de vazão de pico e de tempo de ocorrência da vazão de pico. Além disso, também foram considerados, em alguns testes, os critérios de aplicabilidade de Ponce para onda cinemática e difusão além da formulação do Δx ideal proposto por Fread. Os resultados mostram que o modelo Muskingum-Cunge Todini, modificado para representar o efeito da planície de inundação, é muito promissor. Esse modelo apresentou resultados que se aproximaram muito dos resultados obtidos pelo HEC-RAS, enquanto os outros modelos hidrodinâmicos simplificados apresentaram resultados piores. Com relação aos critérios de aplicabilidade, recomenda-se o uso de um Δx três vezes menor do que o valor sugerido por Fread. Além disso, pode-se concluir que os modelos simplificados podem ser utilizados fora dos limites de aplicabilidade sugeridos por Ponce. / This work has identified, tested and improved simplified flood routing models to verify the advantages and disadvantages presented. The solutions provided by these models were tested by using a full hydrodynamic model considered in this work as an ideal result. The simplified hydrodynamic models used were: A variable parameter kinematics wave model, the Muskingum-Cunge flood routing model, the variable parameter Muskingum-Cunge flood routing model (three and four points scheme) the Muskingum-Cunge modified by Todini (MCT) and the model IPHS1. The full hydrodynamic model used was HEC-RAS. It was also proposed a procedure to represent the effect of the floodplain rivers. To evaluate the behavior of different flood routing models numerical tests were created and were applied to then. The characteristics of synthetic inflow hydrographs, the characteristics of riverbed and floodplain, and the criteria for temporal and spatial discretization were perturbed. The evaluation of the results was made through the errors of conservation of volume, peak flow and time of occurrence of peak flow. Moreover, it was also considered, in some tests, applicability criteria recommended by some authors for different models, such as models of kinematic flood wave and diffusive flood wave. The results show that the Muskingum Cunge Todini, modified to represent the effect of the floodplain flow is very promising. Finally, it is also shown that this model closely approaches the full Saint Venant equation solution (HEC-RAS). The others models were worse than HEC-RAS and MCT. About applicability criteria, it recommends the use of the Δx three times smaller than the value suggested by Fread. Moreover, the simplified hydrodynamic models can be used outside limits of applicability suggested by Ponce about kinematic and diffusive wave.

A flood routing and stage prediction model is developed using the techniques of State Space and Kalman filtering. The governing equation is the physically based hydrologic method of flood routing with the output being an optimal estimate of stage given known inputs of streamflow. These equations are developed in state space and the Kalman filter is employed to estimate the flow and river stage. The model is applied to the Toutle and Cowlitz Rivers in the State of Washington, where the stage is affected by a shifting bed elevation. With the deterministic inputs at Mayfield Dam on the Cowlitz and Tower Road on the Toutle, the optimal output of stage is predicted at Castle Rock on the Cowlitz River. Addition of the Kalman Filter improves stage prediction based on an application to an observed storm event.

A key element of hydrologic routing models is the storage-discharge relationship assumed to follow a certain mathematical form, usually a linear or a power function, the parameters of which are calibrated based on existing inflow-outflow data. While this assumption simplifies the model calibration process, it also constrains the models to operate by this function throughout their flow range. In view of the complex and nonlinear river flow behavior, this approximation undoubtedly introduces errors. This research presents a new hydrologic river routing approach that is not limited by the above assumption. River reaches are modeled as cascades of interacting conceptual reservoirs, with storage-discharge functions identified by the data. A novel parameter estimation approach has been developed to identify these functions and all other model parameters based on control theory concepts. After calibration, these functions indeed exhibit different mathematical forms at different regions of their active variation range. The new approach is applied and successfully demonstrated in real world reservoir and river routing applications from the Nile River Basin. A Bayesian forecasting scheme was also developed that uses the new approach to generate flow forecasts with explicit uncertainty characterization.

This study was conducted at the mountainous catchment part of Batinah Region of the Sultanate of Oman called Al-Awabi watershed which is about 260km2 in area with about 40 Km long Wadi main channel. The study paper presents a proposed modeling approach and possible scenario analysis which uses 1D - hydraulic modeling for flood routing analysis; and the main tasks of this study work are (1) Model setup for Al-Awabi watershed area, (2) Sensitivity Analysis, and (3) Scenario Analysis on impacts of rainfall characteristics and transmission losses. The model was set for the lower 24 Km long of Al-Awabi main channel (Figure 13). Channel cross-sections were the main input to the 1D-Hydraulic Model used for the analysis of flash flood routing of the Al-Awabi watershed. As field measurements of the Wadi channel cross-sections are labor intensive and expensive activities, availability of measured channel cross-sections is barely found in this study area region of Batinah, Oman; thereby making it difficult to simulate the flood water level and discharge using MIKE 11 HD. Hence, a methodology for extracting the channel cross-sections from ASTER DEM (27mX27m) and Google Earth map were used in this study area. The performance of the model setup was assessed so as to simulate the flash flood routing analysis at different cross-sections of the modeled reach. And from this study, although there were major gap and problems in data as well as in the prevailing topography, slope and other Hydro Dynamic parameters, it was concluded that the 1D-Hydraulic Modelling utilized for flood routing analysis work can be applied for the Al-Awabi watershed. And from the simulated model results, it was observed that the model was sensitive to the type of Boundary Condition chosen and taken, channel cross sections and its roughness coefficient utilized throughout the model reach.

This study was conducted at the mountainous catchment part of Batinah Region of the Sultanate of Oman called Al-Awabi watershed which is about 260km2 in area with about 40 Km long Wadi main channel. The study paper presents a proposed modeling approach and possible scenario analysis which uses 1D - hydraulic modeling for flood routing analysis; and the main tasks of this study work are (1) Model setup for Al-Awabi watershed area, (2) Sensitivity Analysis, and (3) Scenario Analysis on impacts of rainfall characteristics and transmission losses. The model was set for the lower 24 Km long of Al-Awabi main channel (Figure 13). Channel cross-sections were the main input to the 1D-Hydraulic Model used for the analysis of flash flood routing of the Al-Awabi watershed. As field measurements of the Wadi channel cross-sections are labor intensive and expensive activities, availability of measured channel cross-sections is barely found in this study area region of Batinah, Oman; thereby making it difficult to simulate the flood water level and discharge using MIKE 11 HD. Hence, a methodology for extracting the channel cross-sections from ASTER DEM (27mX27m) and Google Earth map were used in this study area. The performance of the model setup was assessed so as to simulate the flash flood routing analysis at different cross-sections of the modeled reach. And from this study, although there were major gap and problems in data as well as in the prevailing topography, slope and other Hydro Dynamic parameters, it was concluded that the 1D-Hydraulic Modelling utilized for flood routing analysis work can be applied for the Al-Awabi watershed. And from the simulated model results, it was observed that the model was sensitive to the type of Boundary Condition chosen and taken, channel cross sections and its roughness coefficient utilized throughout the model reach.

The dynamic wave model (the complete form of the saint-Venant equations), as applied to flow routing in irrigation canals or flood routing in natural channels, is associated with parameter and model uncertainties. The parameter uncertainty arises due to imprecision in the estimation of Manning’s n used for calculating the friction slope (sf) in the momentum equation of the dynamic wave model. Accurate estimation of n is difficult due to its dependence on several channel and flow characteristics. The model uncertainty of the dynamic wave model arises due to difficulty in applying the momentum equation to curved channels, as it is a vector equation. The one-dimensional form of the momentum equation is derived assuming that the longitudinal axis of the channel is a straight line, so that the net force vector is equal to the algebraic sum of the forces involved. Curved channel reaches have to be discretized into small straight sub-reaches while applying the momentum equation. Otherwise, two- or three-dimensional forms of the momentum equation need to be adopted. A main objective of the study presented in the thesis is to develop a fuzzy dynamic wave model (FDWM), which is capable of overcoming the parameter and model uncertainties of the dynamic wave model mentioned above, specifically for problems of flow routing in irrigation canals and flood routing in natural channels. It has been demonstrated earlier in literature that the problem of parameter uncertainty in infiltration models can be addressed by replacing the momentum equation by a fuzzy rule based model while retaining the continuity equation in its complete form. The FDWM is developed by adopting the same methodology: i.e. By replacing the momentum equation of the dynamic wave model by a fuzzy rule based model while retaining the continuity equation in its complete form. The fuzzy rule based model is developed based on fuzzification of a new equation for wave velocity, to account for the model uncertainty and backwater effects. A fuzzy dynamic wave routing model (FDWRM) is developed based on application of the FDWM to flow routing in irrigation canals. The fuzzy rule based model is developed based on the observation that inertia dominated gravity wave predominates in irrigation canal flows. Development of the FDWRM and the method of computation are explained. The FDWRM is tested by applying it to cases of hypothetical flow routing in a wide rectangular channel and also to a real case of flow routing in a field canal. For the cases of hypothetical flow routing in the wide rectangular channel, the FDWRM results match well with those of an implicit numerical model (INM), which solves the dynamic wave model; but the accuracy of the results reduces with increase in backwater effects. For the case of flow routing in the field canal, the FDWRM outputs match well with measured data and also are much better than those of the INM. A fuzzy dynamic flood routing model (FDFRM) is developed based on application of the FDWM to flood routing in natural channels. The fuzzy rule based model is developed based on the observation that monoclinal waves prevail during floods in natural channels. The natural channel reach is discredited into a number of approximately uniform sub-reaches and the fuzzy rule based model for each sub-reach is obtained using the discharge (q)–area (a) relationship at its mean section, based on the kleitz-seddon principle. Development of the FDFRM and the method of computation are explained. The FDFRM is tested by applying it to cases of flood routing in fictitious channels and to flood routing in a natural channel, which is described in the HEC-RAS (hydrologic engineering center – river analysis system) application guide. For the cases of flood routing in the fictitious channels, the FDFRM outputs match well with the INM results. For the case of flood routing in the natural channel, optimized fuzzy rule based models are derived using a neuro-fuzzy algorithm, to take the heterogeneity of the channel sub-reaches into account. The resulting FDFRM outputs are found to be comparable to the HEC-RAS outputs. Also, in literature, the dynamic wave model has been applied in the inverse direction for the development of centralized control algorithms for irrigation canals. In the present study, a centralized control algorithm based on inversion of the fuzzy dynamic wave model (FDWM) is developed to overcome the drawbacks of the existing centralized control algorithms. A fuzzy logic based dynamic wave model inversion algorithm (FDWMIA) is developed for this purpose, based on the inversion of the FDWM. The FDWMIA is tested by applying it to two canal control problems reported in literature: the first problem deals with water level control in a fictitious canal with a single pool and the second, with water level control in a real canal with a series of pools (ASCE Test Canal 2). In both cases, the FDWMIA results are comparable to those of the existing centralized control algorithms.

From the Proceedings of the 1972 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - May 5-6, 1972, Prescott, Arizona / Almost all runoff from semiarid rangeland watersheds in southern Arizona results from intense highly variable thunderstorm rainfall. Abstractions, or transmission losses, are important in diminishing streamflow, supporting riparian vegetation and providing natural groundwater recharge. A flood routing procedure is developed using data from the walnut gulch experimental watershed, where flood movement and transmission losses are represented by a system using storage in the channel reach as a state variable which determines loss rates. Abstractions are computed as a cascade of general components in linear form. Wide variation in the parameters of this linear model with increasing inflow indicates that a linear relation between losses and storage is probably incorrect for ephemeral channels.