Simulation Hydraulic Of Karoun River In Iran With Purpose Indicate Capacity Changes Of River Flow With HEC-RAS Model

ABSTRACT: Generally, a river system from source point to the discharge point is subjected to continuous morphological changes for example degradation or aggradations of bed River. The present study attempts to investigate the morphological changes of the Karoun River and explore the effects of the river floods especially within Ahvaz region. In this regard, the observed changes in the rating curve at Ahvaz and Farsiat stations over a specified period showed that for a constant elevation of water surface, the river flow has reduced. In this study the changes of the water level profile using whit hydraulic model HEC-RAS was simulated and profiles were plotted with floods of a 2 to 200 years return period. The results showed that the water profile level with same return period flood for 2000 and 2004 year between Ahvaz-Farsiat stations has increased. This indicates the aggradations of the bed due to sedimentation process. This demonstrates a reduction in the river flow capacity.