The objective of this study is to propose a reduction and manage- ment counterplan of inundation damage in Sacheon-river and Sacheon-bay. For this study, hydrological and geomorphological the present situation and problems were investigated and analyzed in Sacheon city of estuary city. The results of this study are as follows.
The major causes of flood damage in the Sachun-bay attributed to the increased storm water runoff from the tributary and discharge from the Namgang dam with extraordinary rainfall such as typhoon. Based on the flood discharge from the Gawha stream generates cross flow which induces backwater effect in the tributaries and the excessive discharge over the design flood causes partial overflow in the Sachun-bay region. The flood damage estimated also increases due to the high development rate of flood plain and the raised sea level by storm surge.
In addition, there are many identified problems related to water management in Sachun-bay region including shortage of conveyance ability in tributaries, flooding in low-laying area. Furthermore, many other parameters have not yet been studied.
The regulations and plans recommended in this study include basin management plan, master plan of river refurbishment, and plan for low-laying area in sea shore. In addition, it is recommended that the maintenance and complement of hydraulic structures such as bridges and weirs. The reengineering of the existing reservoirs and monitoring and warning systems is needed to reduce potential flood damages.