cates that sunaval is highest at highest turbine 

 efficiencies. Peak efficiency is achieved at i-educed 

 fui-hine loads, typically near 70 percent of maxi- 

 niuin rated capacity." 



Reduced power demand also increases flexibility 

 for adjusting turbine loads to maximize fish sur- 

 vival — sliifting of load demand from turbines 

 where fish passage is high to turbines where fish 

 passage is low (between turbines in a given dam 

 and between dams in the same power-grid sys- 

 tem) . The potential increase in fish survival that 

 might be achieved by using this teclmique, liow- 

 ever, cannot be estimated with accuracy from avail- 

 able data. Among otlier requirements, timing of 

 fish movement should be detennined for shorter 

 jieriods of time, especially for dawn and dusk. 

 Peaks are expected at dawn and dusk (Mains and 

 Smith, footnote 3 ; Gauley et al., 1958 ; Monan et 

 al., footnote 7) and the demand for power fluctu- 

 ates during these hours of the day. 



VERTICAL DISTRIBUTION 



Data on vertical distribution have helped define 

 more precisely the direction that future research 

 should take to develop suitable protective methods. 

 Most fingerlings in turbine intakes of botli The 

 Dalles Dam and McNary Dam are in flows near 

 the ceiling of the intake. These flows pass the tur- 

 bine blades at or near the hub (G. D. Johnson, 

 footnote 2) . If fish remain in these flows, they also 

 must pass the blades near the hub. Protective meth- 

 ods designed to eliminate or nullify the effects of 

 lethal agents, therefore, should be used first at the 

 hub of the ninner. These data also imply that most 

 salmonid fingerlings could be routed into safe by- 

 passes if a guiding system were designed to remove 

 fish only from the upjier 4.6 m. of water within 

 turbine intakes. 



SUMMARY 



1. A frame supporting six fyke nets was used to 

 measure diel movement and vertical distribution 

 of fingerling chinook salmon, sockeye salmon. 

 stcelhea:d trout, and ammocoetes of the Pacific, lam- 

 prey in turbine intakes at Tlie Dalles Dam (1960) 

 and McNaiT Dam (1961) . 



2. The nets were positioned one above the other 



' Hydraulic plant operator training manual. Part II. U.S. Arm.v 

 irps of Engineers, North Pacllic Division. Portland. Orcg. 22 pp. 



in the frame and extended from the intake ceiling 

 to within 1 m. of the floor to strain the center third 

 of flows in a single intake (one-ninth of total tur- 

 bine discharge) . 



3. Diel movement for all age groups and species 

 did not differ significantly between areas of the 

 powerhouse at The Dalles Dam. Although all age 

 groups and species were more abundant at night 

 (7 p.m. to 7 a.m.) than during the day (7 a.m. to 

 7 p.m.), only the I-group salmonids were signifi- 

 cantly so. The night catches of I-group chinook 

 salmon and I-grniip steelhoad trout were 91 and 85 

 percent of the total, respectively, whereas the nig'ht 

 catches of 0-group salmonids and ammocoetes 

 were 67 and 62 percent of the total, respectively. 



4. Vertical distribution of salmonids did not 

 vary between areas of the powerhouse sampled at 

 The Dalles Dam. At both Dams, most I-group fin- 

 gerlings were concentrated in the top two of six 

 nets, or within 4.6 m. of the ceiling of the turbine 

 intakes. At The Dalles and McNary Dams, respec- 

 tively, the results for I-group chinook salmon were 

 73 and 79.3 percent; for I-group steelhead trout, 74 

 and 73.5 percent; and for I-group sockeye salmon, 

 58 and 62.3 percent. 0-group salmonids were less 

 strongly stratified than I-group fingerlings; 48 

 percent were caught in the top two nets. 



5. Vertical distribution of ammocoetes at The 

 Dalles Dam was the reverse of that for salmonids; 

 few were taken in the to}) two nets. 



6. Predominantly night movement of fingerlings 

 through turbines favors higher rather than lower 

 sur\'ival because (a) survival is highest at reduced 

 loads near 70 percent of maximum rated capacity 

 and (b) reduction in demand for power at night 

 results in lower turbine loads. Reduced turl)ino 

 loads also make it jwssible to shift loads from tur- 

 bines where fish passaige is greatest to those where 

 fish passage is least, thus increasing total fish 

 survival. 



7. The concentration of fingerlings near the 

 ceilings of intakes implies fliat most fish pass 

 through the Kaplan runnei"s at or near the hub. It 

 follows that inetiiods for eliminating the effects 

 of lethal agents at the runner should be applied 

 first at tlie hub. In addition, use of deflection and 

 bypass techniques near intake ceilings would be 

 advantageous because the coiiccntration of fish is 

 greatest in this region. 



G08 



U.S. FISH AND WILDLIFE SERVICE 



