A Study on Design High Water Level of Tidal River at Urban Area

To utilize tidal river basin, runoff needs to be controlled effectively. The planning of water control is influenced by analysis of water level when the flood runs off in the river mouth. In order to analyze the water level of the tidal river, several hydraulic parameters are employed. The analysis showed that the gentler the bottom slope, the longer the period of tide oscillation, and the bigger amplitude of tide, the more affected the highest water level of the river. The analysis using perturbative method with above parameters proved that third order approximation is more accurate than second order. Therefore, the third solution can be adopted in deciding the design high water level of tidal river. In this study, we established the high water level design concept in river mouth, and elements which affect this notion is also discussed. Finally, the results are applied to urban tidal river basin to verify the propriety.