Abstract
To manage and distribute water resources efficiently, a rainfall runoff model must be selected and established. To determine the appropriations for this rainfall runoff model, however, accurate flow data must first be obtained. Thus, in this study, the simulated flow of Korea's Geum River was compared with the observed flow at Gongju point, a main control point, using the Streamflow Synthesis and Reservoir Regulation (SSARR) model. The results obtained showed a huge difference between the simulated and observed flows during the low flow period. To determine what caused this difference, a confidence analysis of the formula of the stage discharge curve at Gongju point, developed by the Ministry of Construction and Transportation's Geum River Flood Control Office, was conducted. The flow during the low flow period (between 2003 and 2005) was also measured, and the value obtained was compared with the simulated flow. The long‐term flow as low flow was also calculated, through runoff component analysis, to determine the hydraulic characteristics of the control point and to examine the runoff characteristics during the low flow water utilization seasons.
The study results show that during the low flow period (between 2003 and 2005), the simulated flow (based on the SSARR model) approximated the long‐term flow (based on the runoff component analysis).
The results, however, also show that the observed flow, according to the stage discharge curve formula developed by the Geum River Flood Control Office, was overestimated by about 10% up to 20% both during the normal water level and drought seasons, due to hydraulic factors caused by the spatial characteristics of Gongju point, a main control point. The results of the study reveal that the estimation of the flow must be corrected, and that such flow must be continuously monitored. Copyright © 2008 John Wiley & Sons, Ltd.