Modélisation pluie-débit par le logiciel HEC-HMS de sous bassin versant L'oued Deurdeur_haut chéliff (nord-ouest Algérien)

Abstract

This study aims to model floods in the Derdeur River, a sub-basin of the Upper Chéliff located in the province of Aïn Defla, Algeria. The basin features a marked mountainous topography, with a maximum elevation reaching 1,800 m and an elongated shape (Kc = 1.78), favoring rapid runoff and short-term floods. In the context of hydrological risk management, the use of a reliable model is essential to anticipate extreme events and optimize prevention measures. To ensure the overall consistency of simulated results, it is necessary to develop a validation process. To this end, a sensitivity analysis was performed by adjusting the values of various HEC-HMS model parameters for the watershed. After running the model several times, the simulated flow results were compared with the monitoring values at the basin outlet (where the discharge station is located) for each parameter change. In this regard, the number of CN curves, the SCS lag time and the initial abstraction are calibrated. The measurement results confirmed those of the model and showed that the difference between the observed peak flow and the validated model was about 3.1%, with an R2 value of 0.98 and a Nash-Sutcliffe efficiency of 0.99. This study concludes that the HEC-HMS has proven to be a powerful tool for rainfall-runoff modeling in the Derdeur wadi basin