portions of the watershed. Since 1967, 3091 acres have been harvested in the 

 watershed. 



Existing water yield increases were calculated using the Equivalent Clearcut 

 Area method (see Analysis Methods). The pre fire existing water yield was 

 approximately 14 %. Post fire existing water yield increased to approximately 

 15.7%, slightly over the threshold, but because of stable channel conditions 

 increases are not expected to be detrimental. 



Dirty Ike Creek 



Past and ongoing management activities within the affected watershed include 

 fire, timber harvest, road maintenance and use and recreation. 

 Approximately 1 1 1 acres in the Dirty Ike watershed recently burned. Most of 

 the bum severity was a mosaic fire, with a portion of the State Trust Lands, 

 resulting in a stand replacement conditions. 



Since 1962, approximately 2087 acres have been harvested in the Dirty Ike 

 watershed between State and Plum Creek ownership. Harvest Levels in the 

 watershed range from moderate to high. The upper portion of the watershed 

 has had extensive past harvest history. 



Pre fire existing water yield increases are approximately 7.9% or 516 acre feet 

 Post fire water yield increased to approximately 10.1%, but still well below 

 the 15% threshold developed for Dirty Ike Creek. 



Ashby Creek 



The water yield analysis was calculated for the entire Ashby Creek watershed, 

 which includes the West Fork Ashby Creek 



Past and ongoing management activities within the affected watershed include 

 fire, timber harvest, road maintenance and use, grazing and recreation. 



Dirty Ike Salvage Environmental Assessment 



3-7 



