25Eo Beaver Creek .- — This small stream enters the Willamette 

 River about 272 miles above the mouth, is about 8 miles long, and has 

 not been surveyed. It and its tributary. Parrot Creek , are believed 

 to be of little if any value to salmon o 



25F. t.'olalla River a — (September 5-11, 194-0; Frey and Zimmer. 

 September 17-25, 194-15 Frey and Bryant.) Enters the V/'illamette River 

 about 3I2 miles above the mouth. The stream is approximately 50 miles 

 long^ of vj-hich the lower 38 miles were surveyed. The maximum dis- 

 charge was 22,300 CofoS., on March 31, 1931, and the minimum 25 c.f.s., 

 on September 14^ 1938. The lowest flovra occur from August through 

 October when the flovf is usually under 100 c.foS. This is the period 

 of salmon spawning in the stream. In the section surveyed the stream 

 was 4.0-100 feet wide. The gradient is slight in the lower 25 miles, 

 becoming moderate above. 



About 9 miles above the mouth there is a low gravel pit dam that 

 should be provided with a channel for fish at low water stages. About 

 10 J miles upstream there is an 11 foot high dam on a side channel that 

 forces migratory fish to drop doTmstream and ascend the other channel. 

 There is a 2-foot high stone dam 11 miles above the mouth diverting 

 T/ater to a swimming pool. This dan should be provided vfith a passage- 

 way for fish at low water stages. There is a 5-foot high rock dam lo- 

 cated 132 miles upstream tl:iat has a break at one end and making it 

 passable to fish. There was a low temporary dam 18 miles above the 

 moutb diverting one-fifth of the stream flow to a rock cruslier. Fish 

 can pass the gravel bars at this point if a definite channel is main- 

 tained for themo There is a vrooden irrigation diversion dam 18^ miles 

 upstream that is 2 feet high, diverts 172 c.f,s,, and is impassable at- 

 low Trater. There is a low stone dam 19 miles upstream tl-iat is impassable 

 at low ■water. There is a series of five loyi dams immediately upstream 

 that should be notched for the passage of fish at low water. There is 

 a low dam for a syz-imming pool 19^- miles upstream that should be pro- 

 vided with a channel for fish at lov;^ T/ater. A 2-foot high irrigation 

 diversion dam 19.8 miles upstream is a barrier at low vra,ter. It 

 diverts vmter into a side channel and thence into an irrigation ditch. 

 There is a wooden diversion dam 2 feet high located 23.2 miles up- 

 stream that is a barrier at low water*. The dam diverts into a side 

 channel from which an irrigation flume v/ithdraws more than 2 c.f.s. 



Just belovr the confluence of the North Pork, or 21^,8 miles above 

 the mouth, there is a fast rapids with the stream dropping 10 feet in 

 a distance of 50 feet that could be improved for fish passage. A 

 6-foot cascade located 26.2 miles upstream could also be improved for 

 passage of fish at loyr v/ater. 



All of the diversions on the stream should be screened. 



The lov/er 20 miles of the stream extend through a wide valley bot- 

 toffij, and tliis section is little used by spawning salmon. The vrater 

 temperature in this lower section ranged from 60-72° F., and the spring 



37 



