1948). Johnson (1966), too, dennonstrated the 

 need for such extensions. During his study at 

 Ice Harbor Dam, 3 of 30 chinook salmon with 

 sonic tags were swept back through open spill- 

 gates. 



Our experiments with pipes were made 

 during the salmion migration seasons of 1963 

 and 1964. The purposes in 1963 were to; (1) 

 learn spacial and flow requirements of pipe 

 passageways for adult salmon and trout and 



(2) examine the influence on fish of changes 

 in illumination at the entrance and exit. During 

 1964 the tests were continued to: (1) explore 

 further the spacial requirements (minimum 

 dian^eter of pipe acceptable); (2) study the 

 influence of water velocity, illumination, and 

 water depth in longer pipes (up to 82.3 m.); 



(3) determine fish passing capacity; and (4) 

 improve the transition zone from pool to pipe. 



All tests were made in the Fisheries- 

 Engineering Research Laboratory at Bonne- 

 ville Dam on the Columbia River (see Collins 

 and Elling, I960). Basically the laboratory is 

 a large enclosed rectangular tank about 54.9 m. 

 long, 7,3 m. wide, and 7.3 m, deep. It is lo- 

 cated adjacent to the Washington shore fish 

 ladder on the right bank of the river. Fish 

 are diverted from the ladder, enter and pass 

 through the laboratory on their own volition, 

 and re-enter the ladder to continue their 

 ascent. They are not handled at any time. 



EXPERIMENTAL EQUIPMENT 

 AND DESIGN 



Several different pipe configurations were 

 used in testing the influence of flow and illum- 

 ination upon fish passage. 



Pipe Configuration 



Two pipes were used in the 1963 experi- 

 ments to examine spacial and flow require- 

 ments of pipe passageways and the influence 

 of change in illumination at the entrance and 

 exit. One pipe was 0,3 m. in diameter; the 

 other, 0.9 m. Both pipes were 30,5 m, long 

 and constructed of 0.9-rn, sections of gal- 

 vanized sheet-metal conduit, painted brown 

 on the inside (fig, 1), The two pipes were 

 mounted side by side with a common approach 

 and introductory and exit pools (fig. 2). The 

 pipes had smooth interior surfaces, were level, 

 and installed with the center lines at the same 

 elevation; they were submerged and com- 

 pletely filled with water so that there was equal 

 pressure against the walls. Hinged doors at 

 both ends permitted independent use of either 

 pipe. 



Water velocities were controlled by regu- 

 lating the head on the pipes with stoplogs in 

 the introductory and exit pools; velocities were 



Figure 1. — Construction of the 0.3- and 0.9-m.-dlam- 

 eter pipes from 0.9-m. sections of galvanized sheet- 

 metal conduit, 1963. 



measured with a current meter at the down- 

 stream end. 



Two pipes were used in 1964 (fig, 3) to ex- 

 amine the influence of pipe lengthand diameter, 

 water velocity, depth of flow, light, fish capac- 

 ity, and changes in size at the entrance of a 

 0,6-m, -diameter pipe, 82,3 m. long with two 

 180° turns (fig, 4), and a 0.3-m, -diameter 

 straight pipe, 27.4 m. long. Both pipes were 

 constructed of 0.9 m.-long sections of galva- 

 nized sheet- metal conduit, painted a uniform 

 brown on the inside. Because of the require- 

 ments of the capacity tests, the 0.3-m, pipe was 

 later replaced by a straight section of steel 

 pipe, 27,4 m. long and 0,6 m. in diameter. 



Both pipes had separate introductory and 

 exit pools, permitting simultaneous use. Nor- 

 mally the pipes were submerged and flooded; 

 when they were only partly full, however, the 

 water levels inside and outside were the same. 



Observation stations were established atthe 

 upstream and downstream ends of the two pipes 

 to tally the fish as they entered and left the 

 pipes (Points A and B, fig, 5), Hydroscopes 

 (glass-bottomed tubes) were used to improve 

 visibility. To increase visibility at the exits, 

 luminescent light panels were mounted on the 

 floor of the pools directly below the hydro- 

 scopes. The exit area of the 0,6-m. -diameter 

 pipe also contained a wire fyke to prevent fish 

 from entering the pipe system from the flow 

 introduction pool. Electronic detectors (fig, 5) 

 used in conjunction with a time-event recorder 

 provided a record of fish passage through 

 various sections. 



