9 



+ 



o 

 o 



IE 

 O 



o 

 o 



m 



3 



+ 

 O 



Z 



>• 



> 



P 

 o 



3 

 O 



z 

 o 

 o 



1-9 



JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV, DEC. 



COLUMBIA RIVER BELOW VANTAGE 



Average Monthly Water Quality 



1954-1957 ^,3 22 



50 



