Because riffles are the areas of a stream most affected by flow reduction 

 (Bovee, 1977 and Nelson 1980a) and because the riffle habitats are essential 

 for the maintenance of good trout populations, composites of the riffle cross 

 section for each Mount Haggin stream were analyzed for an instream flow 

 recommendation. Plots of wetted perimeter versus discharge for composites of 

 riffle cross sections were analyzed to determine lower and upper inflection 

 points. These inflection points provide a range of flows which are believed 

 to brackett those flows which are necessary to maintain the high and low levels 

 of aquatic habitat potential (Nelson, 1980a). The final instream flow 

 recommendation is selected from this range of flows. The selection was based 

 on the magnitude and composition of existing fish populations, water avail- 

 ability and quality, the recreational use or potential use, the existing 

 level of environmental degradation and flow contribution to downstream water 

 quality. Fish populations were determined by electrof ishing 1,000 foot 

 sections of each stream. Instream flow recommendations were determined for 

 Ajiierican, California, Oregon, Sevenmile, Seymour, Sixmile, Slaughterhouse, 

 Sullivan, Tenmile, Twelvemile and Willow Creeks during the course of this 

 study. Two other Mount Haggin streams. Deep and French Creeks, were analyzed 

 in 1979 under a separate project by Janet Decker-Hess of the MDFWP (MDFWP, 1981), 



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