112 U.S. BUREAU OF FISHERIES 



is likely to develop when even a very few fish are killed or stunned by 

 electrified water, it is not the policy of the Bureau to recommend the 

 electric screen for general use. 



Sunny side electric screen. — The Sunnyside Canal (capacity 1,500 

 second-feet), main diversion of the Yakima project of the Reclama- 

 tion Service, diverted water from March 14 to October 10, inclusive. 

 During the period of maximum irrigation demand which coincides 

 with the chief period of migration of fish, the flow of the canal 

 exceeded 1,000 second-feet. This canal is the lowest screened diver- 

 sion on the Yakima River. This year operating conditions were 

 much more favorable than during the preceding season, there being 

 a large overflow at the dam to serve as a bypass for the fish. In the 

 past during flood, drift has piled up against the Sunnyside headgates 

 interfering with the electrodes. Permanent facilities for handling 

 such drift have now been provided through the cooperation of the 

 Bureau of Fisheries and the Reclamation Service in the installation 

 of a mechanical winch. 



The operation of the Sunnyside electric screen was uninterrupted 

 throughout the irrigation season. Other electric screens were oper- 

 ated successfully at the Wapato Canal, Old Indian Canal, Tieton 

 Canal, Naches Power House in Washington, and the Kvichak River 

 in Alaska. 



Kvichak electric screen. — The Kvichak River is considered the great- 

 est red-salmon stream in the world. This electric screen is used in 

 connection with the counting of the escapement of salmon up the river 

 to the spawning grounds. This year the Kvichak screen was installed 

 at a point approximately 12 miles upstream from the site used in 1930. 

 At this new location 2 islands, each about one half mile long, divide 

 the river into 3 channels. The electric screen was installed across 

 the central channel at the lower end of the Islands. This central 

 channel, about 660 feet wide, is too deep and swift to permit the instal- 

 lation of the usual type of wooden rack and counting gates. The 

 racks closing the side channels were located at the upper end of the 

 islands. 



The screen consisted of an upstream row of electrodes of %-inch 

 galvanized chain properlj'- weighed and suspended in the water from 

 a piling support. The other side of the electric circuit was connected 

 to a 2K-inch diameter galvanized-iron pipe paralleling the chain 

 electrodes at a point 20 feet downstream. This pipe electrode was 

 supported from a row of piling and so suspended as to clear the 

 bottom of the channel by about 1 foot. Power was furnished from 

 a 9-kilowatt, 125-volt, 60-cycle alternating-current generator driven 

 by a 15-horsepower Fairbanks-Morse gas engine. Approximately 

 80 volts was found to be the most effective potential at the screen 

 and at this voltage the installation drew approximately 50 amperes. 



The action of the electric screen in diverting salmon away from 

 the central channel and directing them up the side channels to the 

 counting weirs was practically 100 percent effective. During the 

 period from June 28 to August 5 the actual count of salmon passing 

 through the Kvichak weir was as follows: 5,064,014 red salmon, 

 5,753 kings, 1,020 chums, and 200 pinks. No fish were observed to 

 pass through the electrified area, and they showed no hesitation in 

 being diverted to the side channels. Throughout this enormous run 

 less than 200 salmon were found to have been killed by the electric 



