10,7 High and Low River-Flow Months 



Level of river flow is most important in any consideration of water-quality 

 management. Periods of high-river flow provide poor guidelines because the 

 assimilative capacity of the river is greatly increased. What has been called high 

 flow occurs less than 90 percent of the time for the month of August, and it is 3 

 to 4 times the median flow. For best guideUnes in managing water quality, some 

 combination of median flow and low flow would provide the best results. What 

 is called low flow occurs 10 percent or less of the time for the low-flow month 

 August. Planning for the low-river flow for low-flow months may be very 

 expensive and B-class classification may be difficult to attain. B-class in low- 

 river-flow months is impossible to attain with the technology assumed in this 

 study. 



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