A Comparison of Geomorphological and Hydrological Methods for Delimitation of Flood Plain in the Mankyung River, Korea

Abstract

River areas include channels, floodplains and all the areas affected by physical and ecological processes in river systems. It is noticeably different from present riparian zone which is bounded by dykes. In this study, two methods for delineation of a floodplain are proposed, which are used for evaluation of the function of a river. One of them is a geomorphology-based technique and the other is hydrology-based inundation analysis. For the Mankyung River, these two methods are applied to delineate the floodplain area. Areas delineated with both methods are mutually compared. The results show that the geomorphology-based method is suitable for the delineation of a valley bottom, including the floodplain in a broader sense, which is unlike an inundated area reflecting contemporary hydrologic conditions. Compared with other flood frequency areas, a 100-year flood inundation area was found reasonable to represent the spatial extent of a floodplain without regard to the longitudinal location along a river. However, it is necessary in certain rivers reach where the division of a channel exists to compare a geomorphological analysis on a valley bottom with an inundation area of different frequencies.

Integrated Prediction Model for Upstream Reservoir Sedimentation in a Weir: A Comprehensive Analysis Using Numerical and Experimental Approaches

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Analysis of Bed Sorting Methods for One Dimensional Sediment Transport Model

“…According to the literature, the Engelund-Hansen equation is the most suitable for sand transport computation. Because it is a dimensionless equation, it has advantages of application [33,34]. According to the investigation of MOLIT, sediment particles of the Geum river bed are composed of 73.48% sand, and it is one of the representative sand rivers among Korea's major rivers.…”