The purpose of this study was to compare dam passage survival, at two spill treatment levels, of yearling Chinook salmon and steelhead smolts at John Day Dam during spring 2010. The two treatments were 30% and 40% spill out of total project discharge. Under the 2008 Federal Columbia River Power System (FCRPS) Biological Opinion (BiOp), dam passage survival should be greater than or equal to 0.96 and estimated with a standard error (SE) less than or equal 0.015. The study also estimated forebay residence time, tailrace egress time, and spill passage efficiency (SPE), as required in the Columbia Basin Fish Accords. However, by agreement among the stakeholders, this study was not an official BiOp compliance test because the long-term passage measures at John Day Dam have yet to be finalized and another year of spill-treatment testing was desired.
Revised: October 29, 2013 |
Published: November 15, 2012