Flood Flow Simulation Downstream of Karkheh Dam and Providing Guidance and Control Solutions with Regard to Geological Setting of Watershed
Subject Areas :Noorodin Bazgir 1 , Alimohammad Akhondali 2 , Kazem Hammadi 3
1 -
2 - Department of Hydrology and Water Resources of Shahid Chamran University of Ahvaz
3 - Director of Basic Water Resources Studies, Khuzestan Water and Power Authority
Keywords: Flood, Karkheh catchment area, Geology, 2D simulation,
Abstract :
The Karkheh basin is located in the west of the country with an area over than 50 thousand square kilometers. Despite the presence of upstream reservoir dams, especially the large Karkheh Reservoir Dam, its downstream plains and cities are still not safe from flood hazards. Considering the geological positioning of the Karkheh River basin, during heavy rainfall, over 70% of the basin area has the potential to produce flooding. The aim of the current research is to simulate flood flow using a one- and two-dimensional model and to use flood channels and storage ponds to divert and store part of the flood in a way that reduces downstream damage to an acceptable level. In order to hydraulically model the flow in flood conditions, the MIKE FLOOD model was used. This model has the ability to simulate complex flows in the river and floodplains hydrodynamically. The hydrological and geometric data required for the model were prepared; Also, flood discharges of 500 to 2500 cubic meters per second with a duration of 11 days and a volume equivalent to 475 to 2376 million cubic meters were introduced as the upstream boundary to the model for simulation in 5 scenarios. The results of the study showed that among the options studied, the "Shakariyeh" pond and floodgate are active in all major floods of the Karkheh River and provide 50% of the total proposed storage volume of the entire system in terms of storage volume. Also, this pond ultimately leads to the Hur-e-Azim wetland, which in addition to helping to meet the environmental needs of the wetland, is also a suitable place to store and store a significant volume of floodwater. This area was determined as the most effective (first priority) location for the delay pond in terms of storage volume and susceptibility to topographic conditions.