gold dredging projects are located in Burnt River Canyon, but it 

 was reported that these operations were discontinued during World 

 Viax II • These dredges operated directly in the stream channel, 

 forming conical mo\mds of gravel tailings five to eight feet in 

 height as they slowly progressed upstream. At the time of obser- 

 vation they had not blocked the channel to the migration of fish 

 at any point o The dredges were aided by power shovels that removed 

 large quantities of gravel from the alluvial fan deposits at the 

 mouths of several small, intermittent tributaries. The stream had 

 an average width of 30 feet in this section, and was discharging 

 slightly more than U5 c.f.So The water temperature was 70 F« at the 

 lower end of the canyon, and the prevailing high water temperature 

 during the summer months is an adverse factor in any evaluation of 

 this section for salmon. The gradient is moderate to fairly steep, 

 having an average rise of U8 feet per mile. There are numerous 

 good shallow riffles, but few large resting pools. The stream bed is 

 composed chiefly of medium and small rubble, and it is estimated that 

 60 percent of the bottom constitutes suitable salmon spawning area. 

 Aside from the high water temperatures that occur in this part of 

 the main Burnt River, it appeal's to be the best part of the stream 

 for salmon spawning. There are three small irrigation ditches, none 

 of which were in operation at the time of observation. 



Section jk) - Bridgeport Vglley t 



B\irnt River Canyon opens above into the Bridgeport Valley, 

 which extends about 15 miles upstream. For the most part the 

 Bridgeport Valley is about a mile wide, but in the upper three miles 

 it narrows rapidly into a small canyon. The stream had an average 

 width of 27 feet, and was discharging lil c.f.s. The water temper- 

 ature was 69 F, at the lower end of the valley. The gradient is 

 slight for the most part, having an average rise of 10 feet per mile. 

 There are few shallow riffles, but pools are almost continuous. The 

 stream bed is composed chiefly of mediim auid small rubble, with a 

 heavy layer of mud and silt. It is estimated that 10 percent of the 

 bottom constitutes suitable salmon spawning area. The upper three 

 miles of this section have a higher gradient, less silt in the stream 

 bed, and better spawning area. There are seven irrigation ditches, 

 with a total water diversion of about 62 c.f.s. 



Section ($) - Hereford Valley ; 



Above Bridgeport Valley, Burnt River extends for a distance of 

 20 miles upstream through Hereford Valley to Unity Dam, This valley 

 has an average width of about one mile. Terraces and bench lands 

 encroach untiH the stream is finally confined to a narrow, rocky gorge 

 for the upper l|- miles. Ihe average width of the stream was 30 feet. 



86 



