ARTIFICIAL FISH PASSAGE FOR DAM OR UNDERWATER BEAM

摘要

Fishes having a homing instinct, such as salmons, sweet fishes, and daces, grow in sea and then return to an upstream region of a river for the purpose of spawning. At this time, these fishes are in trouble with the spawning due to a dam or an underwater beam. If the underground beam having low height difference is constructed in a U-shaped water channel as an artificial fish passage according to the present invention, the fishes can move to the upstream region across the underwater beam. The artificial fish passage of the U-shaped water channel is installed to an opening portion of the underwater beam. An inclination of the water channel is set to be low, and a venturi is installed in the U-shaped water channel to reduce the flow speed. Therefore, the fishes having the homing instinct can swim to a spawning ground around the upstream region across the underwater beam. An artificial fish passage of a spiral pipe may be installed in a dam of a river, and a venturi is installed in the spiral pipe and reduces the inclination of the spiral pipe to reduce the flow speed in order for the fishes having the homing instinct to swim to a spawning ground around the upstream region across the underwater beam. Since the U-shaped water channel and the spiral pipe reduce the consumption amount of the discharge water, the present invention is effective for the dry season.;COPYRIGHT KIPO 2015