usually dry or otherwise impassable. It was reported that no 

 significant number of bluebacks ever had been seen above the 

 dam. The dam diverts about 170 c.f .s, of water into an un- 

 screened canal for irrigation purposes « 



Just below Lake Skaha there is a cascade=type falls about 

 30 feet highj, which appears to be a barrier to fisho There is 

 also a low impassable dam at the outlet of Lake Okanogan which 

 has no fishwayo The towns of Okanogan, Omak, Tonasket, and 

 Oroville all discharge some raw sewage into the river. 



Two species of salmon, blueback and chinook, inhabit this 

 river systemo There is also sane evidence that steelhead trout 

 utilize the lower portion of the river to a limited extent. The 

 bluebacks ascend the river and, after ripening in Lake Osoyoos, 

 spawn in the lake and in the lake section extending upstream to 

 the impassable dam located about 8 miles above Oliver, British 

 Columbiao The upper 20 miles of this 25 mile stream section 

 consists almost entirely of excellent spawning riffles inter- 

 spersed with resting pools. 



Apparently Lake Osoyoos was originally one of the chief 

 producers of blueback salmon in the Coltimbia River system. 

 A number of plantings of adult blueback salmon and fingerlings 

 have been made in Lake Osoyoos by the U» S. Fish and TJlldlife 

 Service. There have been good returns of several thousand 

 adults from this program, and it appears that a good run has 

 been reestablished. In recent years the runs of chinook salmon 

 entering the Okanogan River have not been large. The chief chinook 

 spawning areas are located in the lower 16 mileS| up to the town 

 of Malott, £ind for a distance of a few miles downstream from Lake 

 Osoyoos. The former good runs of this species which entered the 

 Okanogan in order to ascend such tributaries as Salmon Creek and 

 Omak Creek have been exterminated, except for a few fish utilizing 

 the lower Similkameen River* 



18A. Chiliwist Creek «-° (August, 1936 j Hanavan and Wiite leather.) 

 Chiliwist Creek enters the Okanogan River approximately 14 l/2 miles 

 above the mouth. It is a small stream, flowing through a deep ravine 

 between barren hills in its lower reaches, and is entirely diverted 

 for irrigation. Small springs maintain a meager flow in the lower 

 1/2 mile. The stream is of no possible value to salmono 



I8B0 Loup Loup Creek. — (August, 1936 1 Hanavan and TThite leather c) 

 Loup Loup Creek enters the Okanogan River approximately 16 miles above 

 the mouth. Its watershed consists for the most part of barren or 

 sage covered hills ^ with some pine forest in the upper section. The 

 flow is continuous only in the upper section, and was estimated to 

 b© about 10 cofoSo on August 1, 1936. The entire flow is diverted 

 for irrigation into the broad Okanogan Valley. There are two storage 

 reservoirs, and the creek no longer joins the Okanogan River. The 

 stream is of no present or potential value to anadromous fisho 



93 



