2003 Volume 13 Issue 3 Pages 152-162
A bypass fishway, which detours dam reservoir, was proposed for downstream migrating of swimming fish at Pirika Dam. At the upstream end of the fishway, an inlet facility with a spillway was required to guide fish with the river water and return the excess water to the river. The main technical themes in the facility-plan were; i) to find an effective type of spillway for the intended function, and ii) to clarify design parameters to avoid misleading of the fish. Results of field experiment with the fish showed that canal-side-spillway with shallow overflow depth was the most effective type. Moreover, some design parameters related to the above-mentioned technical themes were clarified; such as appropriate overflow depth, shape of the side-spillway, and usage of lighting.