Channel Condition and Dynamics 



1 1 ) Welted Width/Max Depth Ratio: Wetted width/maximum depth ratio values are based on 

 R1/R4 habitat surveys completed in sub-watershed -01 and the LNF rule-set. The determination 

 for the other three sub-watersheds is based on the sediment determination made using the LNF 

 rule-set. Therefore, wetted width/maximum depth ration was rated as functioning appropriately 

 in subwatershed -01 and the others are functioning at unacceptable risk. 



12) Streambank Condition: Streambank stability is based on R1/R4 and walkthrough habitat 

 surveys on portions of most perennial streams on National Forest lands. The LNF rule-set was 

 also used as the majority of Upper Willow Creek lies on private land. Forest Service habitat 

 survey data indicate streambank stability has been impacted by grazing and mining in portions of 

 subwatershed -01. Therefore, this indicator was rated as functioning at risk in -01. For the other 

 three subwatersheds the rule-set, modified by limited habitat survey data was used to determine a 

 functioning at risk rating for subwatershed -02 and a functioning at unacceptable risk rating for 

 both subwatershed -03 and -04. 



13) Floodplain Connectivity: Human activities (roads, conversion of valley bottom lands to 

 agricultural uses and irrigation practices) have reduced floodplain connectivity in the three lower 

 subwatersheds. Although high water during spring runoff typically overtops streambanks and 

 access the floodplain in much of the watershed, the extent of floodplain access has probably been 

 reduced. However, some function still exists. This indicator is rated functioning at risk for 

 subwatersheds -01,-02 and -03. Floodplain access is largely unaltered in -01 and functioning 

 appropriately in this sub-watershed. 



Flow/Hydrology 



14) Change in Peak/Base Flows: The timing and magnitude of peak and summer low flows are 

 altered in -02. -03, and -04 due to the presence of numerous irrigation diversions. Only two 

 subwatersheds have received sufficient timber harvest to possibly affect transpiration rates, -03 

 and -04. This indicator is functioning at risk in subwatersheds -02, -03,and -04 and functioning 

 appropriately in subwatersheds -01. 



15) Drainage network Increase: Subwatershed -01 has few roads and no irrigation ditch system. 

 This subwatershed is functioning appropriately. Higher road densities (0.6-1.6 miles/mile^) and 

 extensive irrigation ditch systems in subwatersheds -02, -03, and -04 have increased the drainage 

 network to some degree. This indicator is functioning at risk in these subwatersheds. 



Watershed Conditions 



16) Road Density & Location: Subwatershed -01 has few roads and stream crossings. This 

 indicator is functioning appropriately. The other three subwatersheds have higher road densities, 

 varying from 0.6 miles/mile^ in -02 to 1.6 miles/mile^ in -04. All three of these subwatersheds 

 contain numerous (22-37) stream crossings. This indicator is functioning at risk in these Habitat 

 Unit Conservations. 



17) Disturbance History: Upper Willow Creek contains substantial amounts of sensitive soil 

 types, primarily granitics in subwatersheds -02 and -03. The greatest acreage of timber harvest in 



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