Author(s): Yuichi Seguchi; Yasuhiro Takemon; Shigeto Inagaki; Tetsuya Sumi
Linked Author(s): Tetsuya Sumi
Keywords: No Keywords
Abstract: Ayu-fish, or sweetfish, is a popular Japanese fish that swims from the sea and migrates up rivers in the spring. But in the Okawa River, which is a distributary channel of the Yodogawa River, the migration of large numbers of ayu has been obstructed by the Kema-suimon Floodgates. This report conveys the findings of a detailedinvestigation, based on a site survey and numerical calculations, of the conditions under which ayu can pass more easily through the Kema-suimon Floodgates from the perspective of current velocity and up-anddownstream water level differences. An operational project that attempted to lower the high-water level of the Yodogawa-ozeki Weir enabled ayu to swim upstream while ensuring river continuity.