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Prediction of flood hydrograph using the modified Cunge-Muskingum method in an ungauged basin: a case study in the Kulsi River basin, India

Bharali Biswadeep, Misra Utpal Kumar

Meteorology Hydrology and Water Management. Research and Operational Applications

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2021

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Vol. 9, Iss. 1-2

1--22

EN

The Cunge-Muskingum routing model is one of the most popular and widely used models for hydrologic channel flood routing. The application of Cunge-Muskingum model to an ungauged basin is hindered by the lack of hydro-meteorological data. In the present study, a method is proposed to predict the outflow hydrograph of an ungauged basin as a solution to this problem. The Cunge-Muskingum method is modified, considering the non-prismatic complex natural channel. The Soil Conservation Service Curve Number rainfall-runoff model is employed to obtain the inflow and lateral inflow hydrographs of the ungauged basins, and the Modified Cunge-Muskingum model is employed to anticipate the flood hydrograph at the outlet of the ungauged basin. The proposed approach is employed to the Kulsi River Basin, India, hypothetically treated as an ungauged basin, and the results are compared with the observed data at the outlet of the basin. The performance of the model is evaluated based on RMSE (50.34 m3/s), peak flow error (39.73%), peak flow time error (-3.44%), total volume error (7.36%), relative error (7.36%), mean absolute error (33.5%), correlation coefficient (0.785), coefficient of efficiency (0.59) and Kling-Gupta efficiency (0.66).The results reveal that the proposed Modified Cunge-Muskingum model is an efficient predictor of the flood hydrograph at the outlet of the ungauged basin.

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Study on the applicability of the SCS CN based models to simulate foods in the semi arid watersheds of northern Algeria

Abdi Ishak, Meddi Mohamed

Acta Geophysica

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2021

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Vol. 69, no. 1

217--230

EN

Algeria has experienced catastrophic foods over the second half of the twentieth century, causing many deaths and extensive material damage. This study was conducted to fnd a suitable event-based rainfall-runof (RR) model for semi-arid conditions, where continuous data are not available in all regional basins. The study compared, based on data availability, the SCS-CN model based on the antecedent moisture conditions (AMC) and four modifed SCS-CN models incorporating antecedent moisture amounts (AMA) in order to fnd the best model to reproduce the food hydrographs in two catchments. The modi fed models were predominant over the SCS-CN method. Nonetheless, the Singh et al. (Water Resour Manag 29:4111–4127, 2015. https://doi.org/10.1007/s11269-015-1048-1) model (M4) and the Verma et al. (Environ Earth Sci 76:736, 2017a. https ://doi.org/10.1007/s12665-017-7062-2) model (M5) were superior and demonstrated more stable structures. Coupled with the Hayami routing model, the models showed promising results and were able to reproduce the observed hydrographs’ shape. However, it was impossible to choose the preferred model since they each excelled as to a criterion. Therefore, the corresponding outputs were combined using the simple average (SA) method and the weighted average (WA) method. We found that the WA method showed better results in the two catchments and allowed a more accurate prediction according to the performance criteria.

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Assessment of two loss methods for estimation of surface runoff in Zaafrania urban catchment, North-East of Algeria

Dahdouh Y., Ouerdachi L.

Journal of Water and Land Development

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2018

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no. 36

37--43

EN

Surface runoff is a major problem in urban catchments; its generation is always related to the amount of effective rainfall dropped over the surface, however in urban catchments the process is considerably altered by the emergence of impervious areas. In this study the Soil Consevation Service – curve number (SCS-CN) and the Green–Ampt loss methods were used in rainfall-runoff modelling in the Zaafrania urban catchment which is located in Annaba city in the north east of Algeria. The two loss methods were carried out within Hydrologic Engineering Center – Hydrologic Modelling System (HEC-HMS), the choice of the appropriate method for simulating runoff hydrographs in the study area was made by comparing the simulated hydrographs versus observed data using visual inspection and statistical analysis. The results indicate that SCS-CN loss method fit better in the case of 100 years return period NSE (0.462) than in 10 years NSE (0.346) and the results of calibration of Green– Ampt loss method for the 100 years return period NSE (0.417) provide best fit than the case of 10 years NSE (0.381). Furthermore, the results of both return periods (10 and 100 years) of SCS-CN loss method provide best fit than the results of return periods (10 and 100 years) of Green–Ampt loss method. It could be concluded that SCS-CN method is preferred to the Green–Ampt method for event based rainfall-runoff modelling.

PL

Spływ powierzchniowy jest głównym problemem w miejskich zlewniach. Spływ jest zawsze uzależniony od opadu, jednak w miejskich zlewniach proces ulega znaczącej modyfikacji z powodu obecności powierzchni nieprzepuszczalnych. W badaniach prezentowanych w niniejszej pracy zastosowano dwie metody – SCS-CN (ang. Soil Coservation Service – curve number) i Green–Ampt do modelowania relacji opad–odpływ w miejskiej zlewni Zaafrania na terenie miasta Annaba na północnym wschodzie Algierii. Obie metody realizowano w ramach modelu HEC-HMS. Odpowiednią metodę symulowania hydrogramu odpływu dobrano na podstawie wizualnej oceny i analizy statystycznej. Wyniki dowodzą, że metoda SCS-CN dawała lepsze dopasowanie w przypadku stuletniego okresu powtarzalności (NSE = 0,462) niż w przypadku okresu dziesięcioletniego (NSE = 0,346). Wyniki kalibracji metodą Green–Ampt zapewniały lepsze dopasowanie dla stuletniego niż dla dziesięcioletniego okresu powtarzalności (NSE odpowiednio 0,417 i 0,381). Ponadto wyniki metody SCS-CN dla obu okresów (10 i 100 lat) wykazywały lepsze dopasowanie niż wyniki uzyskane za pomocą metody Green– Ampt dla tych okresów. Można wnioskować, że metoda SCS-CN ma przewagę nad metodą Green–Ampt w modelowaniu relacji opad–odpływ w odniesieniu do poszczególnych zdarzeń.