to the upstream migration of fish* The Agency Valley reservoir 

 extends for about 3i miles above the dam, and has a drainage area 

 of U20 square miles. The reservoir is of some value to resident 

 rainbow trout. It also supports a large, undesirable population 

 of squawfish and other rough fish 



The North Fork was not surveyed in detail above the reservoir 

 because it has little potential value for anadromous fish, 



ID, South Fork, Malheur River .— (July 22-23, 19U2j Parkhurst.) 

 The South Fork enters the main Malheur about h miles below the River- 

 side dam, or approximately 97 miles above the mouth. The stream 

 extends for a distance of 2U miles, and in addition its principal 

 tributary, Camp Creek, extends another 21 miles to the south. There 

 are many minor intermittent tributaries, The barren foothills in- 

 cluded in the watershed of over 650 square miles have only a sparse 

 cover of sage and grass , The barren nature of the watershed is 

 no doubt responsible for the great natural fluctuation in discharge. 

 It was quite evident from the nature of the banks and the outwash 

 plains at the mouths of the tributaries that the South Fork was 

 subject to flash floods. Although the stream channel had an average 

 width of more than 20 feet, the discharge at the mouth at the time 

 of observation was only 3 c,f,s. The gradient is moderate, and under 

 more favorable flow conditions there would be a considerable amount 

 of spawning area. Further, there is not sufficient flow at low water 

 stages to maintain adequate resting pools as a refuge for trout or 

 salmon. The water temperature was 86.0°F. near the mouth at the time 

 of the survey. Under these conditions the stream must be considered 

 of no value to trout and salmon, 



2, Boise River , — (inspected at various times; not surveyed 

 in detailT) 'ihe Boise River enters the Snake River approximately 

 379 miles above the mouth* The main stem extends for a distance of 76 

 miles to Arrowrock Dam, The Arrowrock reservoir is 12 miles long. 

 Above the reservoir the river extends for an additional 12 miles to 

 the confluence of the North and Middle Forks, 



The Boise River formerly supported good runs of Chinook salmon 

 and steelhead trout. These runs have been exterminated for UO years, 

 due to the early extensive diversion of the flow for irrigation 

 and the intense pollution of the stream by cities and towns along the 

 course. 



1U 



