Gomaspan Dam Catchment Area Runoff Volume Evaluation by SCS Method

Author: Basil Younus Mustafa^1
1Polytechnic University, Technical Engineering College, Civil Engineering Department, Erbil, Iraq

Abstract: This research presents a method for computing daily, monthly and annual runoff volume (annual inflow) for Gamesman dam catchment area on Bastora stream in Erbil Governorate. The procedure is developed by the U.S. Soil Conservation Service (SCS) which depends on physical parameters of the catchment area and daily rainfall depth data in Shaqlawa Meteorological station within the catchment area. The advantage of this method is being straightforward to apply, and the physical parameters are easily determined. The runoff depth and volume was computed upon collecting and determining physical parameters (such as drainage area, land uses, soil type and soil infiltration rate) for the catchment area. The results were compared with estimated depth and volume of runoff suggested by (Sogreah) empirical equation used in the design planning report for Gomspan dam prepared by the Project’s Consultancy team. The results of the comparison revealed the fact that the depth and volume of runoff was over estimated in the planning report.

Keywords: Runoff, SCS, RCN, SRO

doi: 10.23918/eajse.v3i2p195

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