Relative survival of subyearling chinook salmon after passage through the bypass system at the first powerhouse or a turbine at the first or second powerhouse and through the tailrace basins at Bonneville Dam, 1992

In 1992, the NMFS expanded passage survival research at Bonneville Dam to include assessment of passage through the turbines and the bypass system at the First Powerhouse. This assessment was necessary to identify the safest passage routes at Bonneville Dam for juvenile salmon migrating in the summer. The objective of this study was to compare relative survival among marked groups of subyearling chinook salmon released into the bypass system of Bonneville Dam First Powerhouse, the turbines at the First and Second Powerhouses, and at a site in swift water about 2.5 km downstream from the dam. Estimates of long- and short-term relative survival- will be developed by comparing recovery percentages of these different groups. Contract no. DACW57-85-H-0001