|Document Type:||Contract Report|
|Title:||Studies to evaluate the effectiveness of extended-length screens at The Dalles Dam, 1994|
|Author/Editor:||R. F. Absolon, Dean A. Brege, Benjamin P. Sandford, Douglas B. Dey|
|Publisher:||National Marine Fisheries Service|
|Contracting Agency:||U.S. Army Corps of Engineers. Portland, Oregon|
Our research objectives at The Dalles Dam in 1994 were to determine fish guidance efficiency (FGE) and descaling rates of the extended-length submersible bar screen (ESBS) and extended-length submersible traveling screens (ESTS) in the higher-flow turbine units at the east end of the powerhouse. We also evaluated horizontal distribution of migrating juvenile salmonids as they entered the turbine units across the powerhouse.
For each species, FGE was calculated as gatewell catch (guided fish) divided by the total number of fish (guided plus unguided), by species, passing through the turbine intake during the test period. We concluded the following based on tests in 1994: