DIEL MOVEMENT AND VERTICAL DISTRIBUTION OF JUVENILE 

 ANADROMOUS FISH IN TURBINE INTAKES 



BY CLIFFORD W. LONG, Fishery Biologist 

 BUREAU OF COMMERCIAL FISHERIES FISH-PASSAGE RESEARCH PROGRAM, SEATTLE, WASH. 98102 



ABSTRACT 



The behavior of fingerling salmonids was measured in 

 turbine intakes of The Dalles and McNary Dams on the 

 Columbia River to aid in developing methods for reduc- 

 ing fish mortality in Kaplan turbines. At The Dalles 

 Dam, diel movement and vertical distribution were 

 sampled at both ends and at the middle of the section 

 of the powerhouse that housed turbines 1 through 12. 

 At McNary Dam, vertical distribution was sampled in 

 intake 12-C, located near the middle of the River 

 channel. 



Comparisons of day-night occurrence at The Dalles 

 Dam showed that most chinook salmon (Oncorhynchus 

 tshawytscha), steelhead trout (Salmo gairdneri), and 

 ammocoetes of the Pacific lamprey {Lanipetra tri- 

 dentata) were caught at night (7 p.m. to 7 a.m.). 

 Vertical distribution studies at McNary and The Dalles 

 Dams included catches of sockeye salmon (O. nerka) in 

 addition to the above species. Salmonids were taken at 



all depths, but most were in the upper 30 percent of 

 water in the intakes (within 4.6 m. of the ceiling). 

 Ammocoetes at The Dalles Dam (no data for McNary 

 Dam) were concentrated near the center and bottom of 

 the intakes; verj' few were near the ceiling. 



To increase survival of fish by manipulating turbine 

 loads during a 24-hour operational period appears 

 feasible. During darkness when fish movements through 

 turbines increase and power demands decrease, the 

 reduction in turbine loads improves the flexibility for 

 adjusting turbine loads to increase fish survival. 



The concentration of fingerling salmonids near intake 

 ceilings probably causes most of the fish to pass the 

 turbine runner at or near the hub; therefore, methods 

 for eliminating lethal factors at the runner should be 

 applied first at the hub. In addition, use of deflection 

 and bypass techniques near intake ceilings would be 

 advantageous because the concentration of fish is 

 greatest there. 



The behavior of fingerling salmonids in turbine 

 intakes, inchiding their time of passage and distri- 

 bution in the ■n'ater mass, can profoundly influence 

 development of efficient and economical methods 

 for reducing fish mortality in turbines. The need 

 for fish protection at dams is becoming particu- 

 larly acute in the Columbia Basin because the 

 progeny of upriver stocks of salmonids soon will 

 be forced to pass tlirough the turbines of 8 to 10 

 dams to reach the sea. 



At present, normal spring flows are divided 

 about equally between spillways and turbines; 

 numbers of j'oung fish migrating downstream pre- 

 sumably pass through the spillways and the tur- 

 bines in proportion to the water passed by each. 

 Studies at McNary and Big Cliff Dams under 

 nonnal operating conditions (wicket gates opened 



Published May 1968. 



FISHERY BULLETIN: VOLUME 66, NO. 3 



75-80 percent) have shown that mortality of yoimg 

 salmon in Kaplan turbines is about 11 percent, 

 whereas mortality in the spillway is comparatively 

 light — 2 percent (State of Washington Depart- 

 ment of Fisheries ; ' Schoeneman, Pressey, and 

 Junge, 1961). Similar mortality is assumed to oc- 

 cur at other dams with comparable turbine de- 

 signs and operational features. 



Unless solutions are found, the total mortality 

 will increase in the future. When the Corps of 

 Engineers" Pi'ojects are completed, almost all water 

 in the Coliunbia Basin's flow regime eventually 

 will pass through turbines, eliminating the rela- 

 tively safe passageway now provided by water 



1 state of Washington Department of Fisheries. Research re- 

 lating to mortality of downstream migrant salmon passing 

 MeXary and Big Cliff Dams. Progr. Rep. Fish. Eng. Res. Program. 

 1960, N. Pac. Div., U.S. Army Corps Eng.. pp. 122-126. 



599 



319-171 O - 68 - 11 



