Studies to evaluate the effectiveness of extended-length screens at The Dalles Dam, 1994

In 1993, mean FGE at The Dalles Dam for yearling chinook salmon was 73, 60, and 44% for the extended-length submersible bar screen (ESBS), extended-length submersible traveling screen (ESTS) and STS, respectively. Mean FGE for subyearling chinook salmon was 59, 51, and 23% for the ESBS, ESTS, and STS, respectively. Specific research objectives at The Dalles Dam in 1994 were 1) Determine the FGE of an ESBS and an ESTS with juvenile salmonids (especially yearling and subyearling chinook salmon) in the higher-flow turbine units at the east end of the powerhouse during the spring and summer outmigration. 2) Evaluate the effects of an ESBS and an ESTS on juvenile salmonid descaling rates in the higher-flow turbine units at the east end of the powerhouse. 3) Evaluate the horizontal distribution of juvenile salmonids as they enter the turbine units across the powerhouse. Contract no. E96930030