Experimental Study on a Steep Pool-and-Weir fishway using Ayu
Proceedings of the International Symposium on Fishways '95
The Organizing Committee for International Symposium on Fishways '95 in Gifu
In Japan fishways are usually constructed more mild slope than 10%, because the targets of the fishways are almost always Ayu fish which is 10-20 cm long. However, the fishways in sabo dams sometimes need to be settled more steep slope than 10%. Therefore the authors tried to examine the possibility of a steep pool-and-weir fishway for sabo dams through fishway experiments using Ayu fish. The authors confirmed that the Denil type fishways are not suitable for Ayu fish in the field. As a result of the experiments, it is confirmed that Ayu ascends the pool-and-weir fishways of 20-30% gradient in limited water levels (less than 10cm high on each weir).