ods for eliminating lethal agents at the turbine 

 blades can be applied at the specific area through 

 which most of the fish pass. Knowledge of the ex- 

 tent of fish concentrations also can aid in determin- 

 ing the feasibility of guiding them into safe 

 bypasses. 



Information is available on diel movement and 

 distribution of fingerling salmonids at several 

 points in the river system. Mains and Smith ^ stud- 

 ied timing and distribution of fingerling move- 

 ment in river channels; Gauley, Anas, and ScUot- 

 terbeck (1958) investigated diel niovement in spe- 

 cial bypasses at Bonneville Dam. Because the 

 physical environment in these studies differed 

 markedly from that in turbines and associated 

 water passages, tlie data could not be. applied to 

 turbine areas with complete confidence. Additional 

 studies accoi'dingly were projwsed. 



This paper reports on experiments at two dams 

 on the Columbia River to acquire data on timing 

 and distribution of fingerling salmonids entering 

 turbine intakes. In 1960, diel movement and verti- 

 cal distribution of fingerling salmonids were in- 

 vestigated at The Dalles Dam; data on lamprey 

 ammocoetes also were obtained. In 1961, the ver- 

 tical distribution of fingerlings was studied at 

 McNary Dam. 



RESEARCH AREAS 



The Dalles and McNary Dams, operated by the 

 U.S. Army Corps of Engineers, are hydroelectric 

 projects on the Columbia River (fig. 1) with maxi- 

 mum heads of 27.0 and 27.5 m., respectively. De- 

 signs and dimensions of low-head dams on the 

 Columbia River are similar, but the powerhouses 

 are located parallel (The Dalles) or at a right 

 angle (McNary) to the course of the River (fig. 2) . 



At the times of these experiments, in 1960 and 

 1961, The Dalles Dam had 12 operative turbines 

 and McNary liad 14. Turbines of both Dams are 

 equipped with three intakes — A, B, and C. Each 

 intake has a gatewell, or vertical shaft, which 

 extends from an opening in the ceiling of the in- 

 take to the forebay deck. Figure 3 is a cross section 

 of an intake at The Dalles Dam, showing the gate- 

 well and other features. The turbines and turbine 

 intakes of McNai-y Dam have a similar design. 



= Mains, J. E., and J. M. Smith. Determination of normal stream 

 distribution, size, time and current preferences of diownstream 

 migrating salmon tind steclhead trout in tbe Columbia and Snake 

 Rivers. Progr. Rep. Fish. Eng. Res. Program, 1956. North Pacific 

 Division, U.S. Army Corps of Engineers, pp. 14-26. 



RIVER FLOW 



MCNARY DAM 



SPILLWAY 



-« RIVER FLOW 



POWERHOUSE TURBINES 



Figure 2. — Comparison of The Dalles and McNary Dams. 

 The orientation of the powerhou.?e of The Dalles Dam, 

 nearl.v parallel to the course of the River, cau.ses water 

 to turn nearly 90° to pass through turhiiies. The power- 

 house of McNary Dam is oriented at right angles to the 

 course of the River. 



DESIGN AND OPERATION OF SAMPLING 

 APPARATUS 



A special intake frame supiDorting six fyke nets 

 (fig. 4) was used to capture fingerlings passing 

 tlirough turbine intakes at The Dalles and McNary 

 Dams. The fyke nets were installed one above the 

 other in the frame. When the frame was installed 

 in the intake, the nets extended from the ceiling of 

 the intake to within 1 m. of the floor and strained 

 the center flows of the intake. Nearly one-third of 

 the flow of a single intake (one-ninth of the flow 

 of a single turbine) was strained by the six nets, 

 discounting slightly reduced flows through the 

 nets owing to liead loss caused by the webbing. 



The frame was lowered through the intake gate- 

 well (fig. 3) with a gantry crane operated by per- 

 sonnel of the U.S. Army Corps of Engineers. After 

 the frame was installed, the turbine discharge was 

 set. Normal fluctuations in total head on the tur- 

 bine produced minor changes in turbine discharge 

 during each test. Water velocities without the nets 



JUVENILE ANADROMOUS FISH IN TURBINE INTAKES 



601 



