Cobb. — Protecting Migrating Pacific Salmon. 149 



tiveness of the established fishways. Observation at the Wapato 

 and Sunnyside dams developed that many fish were to be seen 

 jumping- at both dams when the annual runs were on, and it was 

 noticed that quite a few managed to get over the dams in this 

 way, and the bigger the flood in the river the easier it appeared 

 to be for the fish. In order to determine whether fish were 

 passing through the fishway of the Sunnyside dam, last spring, 

 during the steelhead run, a trap was placed at the upper exit of 

 the fishway. This trap was left in for several weeks, and during 

 that period not a steelhead was captured, the catch consisting 

 of squawfish and suckers, none of which are inclined to jump out 

 of the water. During this period plenty of steelheads were, 

 however, observed jumping along the face of the dam. 



Previous investigation elsewhere had developed that the 

 fatal weakness of the standard type of pool and fall fishway is 

 that the entrance to the fishway is so far downstream that salmon 

 and trout almost invariably miss it, and the writer is impelled 

 here to express the fear that but few species of fish other than 

 suckers and squawfish would be apt to find it. 



During the preceding winter a plan radically modifying the 

 pool and fall system had been prepared and the modified fish- 

 ways are now under construction in both dams. In this the 

 device is carried a certain distance down stream, then turned at 

 right angles, thence turned again to face toward the dam, and 

 carried back to the foot of the apron of the dam. This makes a 

 structure resembling a staircase with one acute turn and landing 

 and in this way reduces at least one-half the extreme distance 

 of the fishway below the dam. By making the entrance to the 

 fishway parallel to the face of the dam and just at the foot of it a 

 convenient and easily found gateway is provided for the salmon 

 to enter. A somewhat similar plan has been found to work suc- 

 cessfully in the Ament dam on the Rogue River in Oregon, near 

 Grants Pass, where it superseded one of the old type which had 

 proved worthless. 



As the Sunnyside dam is quite wide, while the river just 

 below it is broken up into pools and shallows, it has been de- 

 cided to also construct another fishway of the modified type on 

 the western side of the dam. In the new pool and fall system 

 being installed in the Wapato dam, the pools are 7 feet long by 

 8 feet wide by 4 feet deep while the openings for the water to 



