lA. little Salmon River . — (October 9, 19h2; Parkhurst and Bryant.) 

 The Little Salmon River enters the main Salmon River at Rigging, Idaho, 

 approximately 82 miles above the mouth. It is about Ii3 miles long, of 

 which the lower 3U miles were surveyed. Near the mouth the stream had an 

 average width of about 50 geet. The discharge was 210 c.f.s. and the 

 water temperature was 5U.5 F. The lower 2k miles has a fairly steep 

 gradient in many places and a large amount of bedrock and large rubble. 

 Good spawning area is not extensive. In the upper 10 miles of the section 

 surveyed the stream has a sli^t gradient and a large amovmt of mud and 

 sand. There were 76,000 square yards of suitable spawning area, con- 

 stituting approximately 9 percent of the total bottom in the portion 

 surveyed. No total barriers to fish were found, but several small falls 

 and c ascades render the upper section difficult of access to salmon 

 dtiring low-water stages. No salmon were seen during the siurvey, and it 

 was reported that none had been seen spawning in the Little Salmon for 

 several years. The stream formerly supported a fair run of Chinook 

 salmon. It is easily accessible, and the fish were formerly subjected 

 to an intensive sport fishery. It is of little or no value as a salmon 

 producer at present, but has some potential value. 



lA-(l), Rapid River. — (Not surveyed) Rapid River enters the Little 

 Salmon River approximately k miles above the mouth. The stream is about 

 21 miles long, and was discharging about 2$ c.f.s. Its principal tributary 

 is lA.-(l)a , the West Fork, about 9 miles long. Rapid River was reported 

 to support a small run of Chinook salmon, 



IB. South Fork, Salmon River . — (Not surveyed) The South Fork 

 enters the Salmon River approximately 129 miles above the mouth. It is 

 about 80 miles long, Gaging-station records for the water-year I9UO-I9UI 

 (U.S.G.S., I9U2) give the mean discharge as 1,506 c.f.s. at a point 

 about 20 miles above the mouth. The principal tributaries are IB-(I) , 

 the Secesh River, entering approximately 3U miles above the mouth and 

 extending about 22 miles, and lB-(2) , the East Fork, entering approxmately 

 3$ miles above the mouth, and together with lB-(2)a , Johnson Creek, extend- 

 ing about 60 miles. The East Fork was reported to be often turbid from 

 mining silt below Stibnite, Idaho, approximately 26 miles above the conflu- 

 ence with the South Fork. The South Fork is difficult of access, and a 

 large part of the watershed is seldom frequented. The stream is known to 

 have formerly supported large rims of Chinook salmon and steelhead. The 

 present condition of these i*uns has not been determined, but it is report- 

 ed that they still occur to some extent. 



IC. Middle Fork, Salmon River . — (June 20-July 2U, 19Ul; Parkhurst, 

 Zimraer, Frey, and Bryant.) The Middle Fork enters the Salmon River approxi- 

 mately 191 miles above the mouth. The stream is about IO6 miles long, of 

 which the upper 88 miles and all the major tributaries were surveyed. It 

 is the largest and most important tributary to the main Salmon River, 

 Gaging-station records for the water-year 1938-39 (U.S.G'.S., 19U0) gives 

 the mean discharge as 1,U8U c.f ,s, at a point about 30 miles above the 

 mouth. The stream width decreased from about 200 feet near the mouth to 

 7$ feet at the confluence of Bear Valley and Marsh Creeks, which is con- 

 sidered the point of origin. 



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