Proceedings of the Korea Water Resources Association Conference (한국수자원학회:학술대회논문집)
- 2015.05a
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- Pages.173-173
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- 2015
Determination of Design Flood Levels for the Tidal Reach of the Han River
- Jun, Kyungsoo (Graduate School of Water resources, Sungkyunkwan University) ;
- Li, Li (Graduate School of Water resources, Sungkyunkwan University)
- Published : 2015.05.27
Abstract
The flood water level in tidal river is determined by the joint effects of flood discharge and tidal water levels at downstream boundary. Due to the variable tidal boundary conditions, the evaluated design water levels associated with a certain flood event can be significantly different. To avoid determining of design water levels just by a certain tidal boundary condition and remove the influence of variability in boundary condition from the evaluation of design water levels, a probabilistic approach is considered in this study. This study focuses on the development of a method to evaluate the realistic design water levels in tidal river with taking into account the combined effects of river discharge and tidal level. The flood water levels are described by the joint probability of two driving forces, river discharge and tidal water levels. The developed method is applied to determine design water levels for the tidal reach of the Han River. An unsteady flow model is used to simulate the flow in the reach. To determine design water levels associated with a certain flood event, first, possible boundary conditions are obtained by sampling starting times of tidal level time series; then for each tidal boundary condition, corresponding peak water levels along the channel are computed; and finally, design water levels are determined by computing the expectations of the peak water levels. Two types of tides which are composed by different constituents are assumed (one is composed by