9F* South Fork, Clearwater River *— (September, 19 38 j Hanavan 

 and WildingTJ The South Fork joins the Middle Fork to form the main 

 Clearwater River at Kooskia, Idaho, approximately 75 miles above the 

 mouth* The South Fork also is about 75> miles long* A power dam 

 about 21 miles upstream, near Grangeville, Idaho, is provided with a 

 poor fish ladder, and is considered a barrier to the upstream passage 

 of fish. Gaging station records taken just below the powerhouse near 

 Grangeville for the period 1910-<L o l6 and 1923-19U8 show a maximum re- 

 corded flood of 12,600 c*f .s* in May, I9U8* The minimum recorded 

 flow according to U.S. Geological Survey published reports was Ul 

 c.f .8. in November, 1931* The average discharge for 26 years was 803 

 c*f*s* 



The South Fork was extremely turbid at the time of survey, 

 due to gold dredging operations* Because of the lack of visibility 

 it was impossible to evaluate the spawning area* The disruption 

 of the stream bed by gold dredges and the resultant heavy silting 

 throughout most of the stream may be harmful to the production of 

 both salmon and trout* 



9G, Middle Fork Clearwater River * — (October 6-7,1938; 

 Parkhurst and Morton*) The Middle Fork joins the South Fork to 

 form the main Clearwater River at Kooskia, Idaho, approximately 

 75 miles above the mouth* The stream is 2k miles long, and is form- 

 ed by the confluence of the Lochsa and Selway Rivers* It is access- 

 ible to migratory fish throughout the course* At the time of the 

 survey the stream was 375 feet wide at the mouth, and maintained an 

 average width of more than 300 feet in the lower 10 miles* Dis- 

 charge measurements are not recorded for the Middle Fork* However, 

 gaging station records kept by the U.S* Geological Survey for the 

 Lochsa and Selway Rivers, plus our estimated flows for the minor 

 tributaries entering below the recording stations indicate a dis- 

 charge at the mouth of the Middle Fork of approximately 1,100 c*f*s* 

 at the time of the survey* The water temperature ranged from 56°F 

 to 58 F* The gradient is moderate throughout, with numerous good 

 shallow riffles and adequate resting pools* The stream appears to 

 present excellent conditions for the production of salmon and steel- 

 head trout* There were approximately 620,000 sq* yd* of suitable 

 spawning area, constituting 19 percent of the total stream bed* No 

 salmon were seen, but a spring run of steelhead trout was reported* 

 The stream is of little value at present to anadromous fish, but it 

 has great potential value for salmon and steelhead trout* 



9G-(1) Lochsa River * — (October 8-9,1938; Hanavan, Parkhurst, 

 Morton, and Wilding,) The Lochsa and the Selway Rivers join to form 

 the Middle Fork of the Clearwater approximately 2k miles above the 

 mouth of the latter stream* The Lochsa is approximately 75 miles 

 long, of which the lower 15 miles were surveyed* The stream extends 

 through the Net Perce, Clearwater, and Lolo National Forests* There 

 are few roads reaching the river, and most of its course is through 

 a wilderness area practically unmolested by man* The stream had 

 an average width of liiO feet in the section surveyed, and was dis- 

 charging U03 c*f*s* at a U*S* Geological Survey gaging station lo- 



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