REEVALUATION OF THE FLOOD AND THE FLOOD CONTROL PLAN AROUND THE DAIJUU WEIR IN THE YOSHINO RIVER BY USING THE WATER LEVEL DATA AND THE RIVER SURVEY MAP IN THE MEIJI ERA

Abstract

The authors analyzed the hydraulic features of the Daijuu Weir and neighboring levee of the Yoshino River in the historical perspective, as the structures are important factors of flood control for the river. Firstly, the authors analyzed the precious data of water level observations around the Weir started by De Rijke, a Dutch engineer in 1883. Then using a river survey map surveyed in 1901, they restored the status of levees of the Yoshino River before modern improvement works. Thirdly they analyzed a relationship between the Yoshino River Levee and the Daijuu Weir based on the newspaper articles of the fifty years of period from 1878 through 1927. As the conclusion they reevaluated the flood and flood control plan of the Yoshino River around the Daijuu Weir.