Date

2014-08-01

Author

Mussen, Timothy D.
Patton, Oliver
Cocherell, Dennis
Ercan, Ali
Bandeh, Hossein
Kavvas, M. Levent
Cech, Joseph J.
Fangue, Nann A.

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

22
views

0
downloads

Cite This

Entrainment through water-diversion structures is a major passage challenge for fishes in watersheds worldwide. Behavioral guidance devices may be effective in passing fish by diversion inlets, thereby decreasing entrainment without reducing water-diversion rates, but data on their effectiveness is limited. In California's central valley, out-migrating Chinook salmon (Oncorhynchus tshawytscha) are a species at risk for entrainment through unscreened, small-scale water-diversion pipes. Therefore, we tested entrainment susceptibility and behavior of juvenile Chinook salmon in a large-river-simulation flume at a "river" velocity of 0.15 m.s(-1) with a 0.46 m diameter pipe diverting water at 0.57 m(3).s(-1), during the day and night. Compared with control conditions (no fish deterrent devices present), mean fish entrainment increased by 61% (day) and 43% (night) when underwater strobe lights were active, decreased by 30% when using a metal vibrating (12 Hz) ring during the night, and was unaffected by velocity cap attachments. Fish entrainments started at water velocities of 0.8 m.s(-1) and decreased by 54% from spring to summer, possibly resulting from decreased pipe-passage frequency and smaller fish-school sizes. Our findings suggest that substantial entrainment can occur if fish repeatedly pass within 1.5 m of active unscreened diversions, with an estimated 50% of fish lost after encountering 18 pipes in spring and 50 pipes in summer.

URI

https://hdl.handle.net/11511/100777

Collections

Department of Civil Engineering, Article