Table 5. — Decrease in permeability of bottom materials from salmon spawning beds with 



addition of fine particles 1 



[Permeability readings corrected for standard viscosity of 1.0 centipoise at 68° F.] 



No fine particles added 



Fine particles added 



Fine particles added consisted of materials retained by a 0o208-mm. 

 (5 parts) and a 0, 104-mmo (3 parts) sieve and passing through a 0. 104-mm.o 

 sieve (12 parts). 



Table 6. — Mean percentage of total volume of bottom materials in five size classes of fine 

 particles from upstream Harris River before siltation from logging, after siltation, and 



after siltation and flooding 



iHarris River was observed to carry heavy silt loads on October 12 and 17, 1959. 

 ^Flooding occurred on about November 6 and December 6, 1959. 



13 



