Movement of Fall Chinook Salmon Fry Oncorhynchus Tshawytscha : A Comparison of Approach Angles for Fish Bypass in a Modular Rotary Drum Fish Screen.

摘要

The Pacific Northwest National Laboratory (PNNL) performed tests to determine whether a significant difference in fish passage existed between a 6-ft screening facility built perpendicularly to canal flow and an identical screening facility with the screen mounted at a 45-degree angle to the approach channel. A modular drum screen built by the Washington Department of Fish and Wildlife was installed at PNNL`s Aquatic Ecology research laboratory in Richland, Washington. Fall chinook salmon fry were introduced into the test system, and their movements were monitored. A total of 14 tests (400 fish per test) that lasted 20 hours were completed during April and May, 1996. There was no significant difference in fish passage rate through the two approach configurations. Attraction flow to the bypass across the face of the screen was more evident for the angled approach, although this did not appear to play a significant role in attracting fish to the bypass. Approach velocities at the face of the screen did not exceed the 0.4 fps criteria for either approach configuration and posed not threat to fish. No fish passed over, around, or through the drum screen during any test.