a) Washington Creek upstream study area showing predominance 

 of boulders. 



b) Washington Creek upper mined study area, note spread of 

 flow, multiple channels, lack of surface water. 



Figure 43. Washington Creek upstream and mined area on 9 

 September 1977 showing reduction of i nstream^cover due to 

 gravel removal operation (flow level [O. II m /sec] = 20 per- 

 cent of mean annual flow). Other habitat alterations include 

 increased braiding, siltation, and intergravel flow. 



154 



