Suspended sediment concentrations remain low at low to medium stream velo- 

 cities. The concentration increases considerably at high discharge rates in 

 the logged stream but were found to be no greater than in the unlogged control 

 stream. 



Sediment is a particularly important factor in salmon spawning streams. It 

 affects subsurface water flows in streambed gravels and consequently it affects 

 the supply of oxygen necessary for salmon egg and fry survivali.'. The iinpor- 

 tance of this factor and the high variability found between samples and streams has 

 led to a plan for intensfying sediment studies both in the streams and on the land. 

 This phase of the study is being investigated jointly by the Research Center and 

 the Fisheries Research Institute. 



1/ Royce, William F. On the possibilities of improving salmon spawning areas. 

 Trans. Twenty-Fourth N. American Wildlife Conf. , pp. 356-366, 1959. 



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