18C» Salmon Creeko— (August, 1936; Hanavan and Whiteleather.) 

 Salmon Creek enters the Okanogan Pfiver approximately 2 5 miles above 

 the moutho The stream is about 25 miles long. The Conconully 

 Reservoir Dam located about 16 miles above the mouth, is a total 

 barrier to fish. This dam was completed by the Bureau of Reclamation 

 in 1916. A similar, smaller dam is located on a tributary a short 

 distance above the Conconully Dam. The purpose of these dams is 

 to store water for use during the irrigation season, and to this 

 end practically the entire flow is impounded. Only a small amount 

 of ''Vfasted'* water may reach the Okanogan River during exceptionally 

 high run-off stages. During the irrigation season all the water 

 released from the reservoirs is taken out by irrigation diversions,, 

 Therefore there is never any significant flow in the lower portion 

 of the creek. This has resulted in the complete extermination of 

 salmon and steelhead in the stream* 



Before the completion of the irrigation project Salmon tlreek 

 supported a large run of chinook salmon, for a stream of its size. 

 It was important to the Indians as a fishing place, and the natives 

 dried many salmon there, but it is now of no further use to migratory 

 fish. 



18D. Omak Creek . — (April 27, 1937; Baltzo and Jobes.) Omak 

 Creek enters the Okanogan River approximately 31 l/2 miles above the 

 mouth. The stream is about 25 miles long, of which the lower 3/4 

 mile was surveyed, up to an impassable mill dam 16 feet in height. 

 The stream was 15 feet wide at the mouth, and was discharging 30 

 c.f.s. at the time of the storvey. The water temperature was 55°F, 

 at the mouth. The gradient is moderate, and was estimated to be 

 50-60 feet per mile. There were about 4,000 sauare yards of medium 

 and small rubble constituting 52 percent of the stream lied in the 

 section surveyed. A large part of this was considered to be suitable 

 salmon spawning area. There are two irrigation ditches in the section 

 surveyed. Neither of these is screened to prevent loss of fish. The 

 ditches were not in use at the time of the survey, and the diversion 

 dams were not barriers to fish. However, it was reported that in 

 late siunmer the lowermost ditch, about 400 yards above the mouth, 

 withdraws the entire flow remaining in the stream bed at that point, 

 and the diversion dam at that time is a total barrier. 



The stream section above the lumber mill dam contains little 

 potential salmon spawning area. The St. Mary's Mission diversion dam 

 is located at the lower end of a steep gorge about 5 miles above 

 the lumber mill dam. This dam is 5 feet high, and is constructed 

 on the crest of a bedrock slope or cascade having a drop of 12 

 feet. The upper steep cascade section through the rocky gorge 

 is composed almost entirely of bedrock and large rubble, and is 

 of no possible value to salmon. 



Chinook salmon and steelhead trout were reported formerly to 

 have spawned in small numbers up to the mill dam. These runs were 

 necessarily included in the trapping 'of fish at Rock Island Dam 



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