Considering the flood intensity of Karoun’s sub-basins and effective parameters on it in lumped and semi-distributed management simulation of flood hydrograph

Karandish, Fatemeh; Ebrahimi, Kumars; Porhemmat, Jahangir

doi:10.22059/jwim.2014.50038

Considering the flood intensity of Karoun’s sub-basins and effective parameters on it in lumped and semi-distributed management simulation of flood hydrograph

Document Type : Research Paper

Authors

Fatemeh Karandish ¹

Kumars Ebrahimi ²

Jahangir Porhemmat ³

¹ Assistant Professor, Department of Water Engineering, Faculty of Water and Soil, Zabol University, Zabol, Iran

² Associate Professor, Department of Irrigation and Reclamation, Faculty of Agricultural Engineering and Technology, College of Agriculture and Natural Resources, University of Tehran, Tehran, Iran

³ Associate Professor, Soil Conservation and Watershed Management Institute, Tehran, Iran

10.22059/jwim.2014.50038

Abstract

The response of Karoun basin in Lumped and Semi-distributed simulation were compared. Also, the flood intensity of the sub-basins and the effects of physical parameters on flood hydrograph have been investigated. Results demonstrated that there was no significant difference between the characteristics of flood hydrograph in lumped and semi-distributed simulation. Also, results showed that the flood intensity of each sub-basins doesn’t just depend on the area of each sub-basin and further parameters such as the distance of each sub-basins based to the basin outlet and some other physical or climatic parameters would affect the flood intensity of each sub-basins. Based on the results of prioritizing the intensity of each sub-basins in the study area, Barez and Dazakabad sub-basins are in the first and seventh priorities based on the share of sub-basins on flood discharge. However Barez and Soulekan sub-basin ranked in first and seventh proiorities based on the share of sub-basins per unit area. Sensitivity analysis has been done based on five important parameters including; main river slope, Gravelius coefficient, curve number, area of sub-basins and the average slope of basin. Results indicated that the curve number has been the most effective factor on the flood rates of each sub-basin. Therefore, a suitable management for the land use changes as the most effective factor on curve number would greatly control the basin flood intensity.

Keywords

curve number

flood hydrograph

gravelius coefficient

HEC-HMS

prioritizing