recently identified grazing-related impacts and the inappropriate use a diversion on State 

 properties. Corrective measures are now being planned for all of these identified 

 problems beginning in 2006. 



Fisheries and other Monitoring 



In 2004 and 2005, we continued to monitor fish populations in upper Cottonwood 

 Creek in the area of a water lease, downstream of the Dreyer Diversion. The water lease 

 was initiated in 1997, prior to which time a major diversion (Dreyer Diversion) 

 completely dewatered a middle portion of Cottonwood Creek during the late irrigation 

 season. We also developed a new stage discharge relationship for the Dreyer ditch, 

 which will be used to monitor irrigation and instream flows (Figure 1 8) 



Fish population monitoring in the water lease area (mile 12.1) show higher 

 densities of WSCT following increased flows and the recent recovery of WSCT from a 

 recent drought-related low in 2003 (Figure 1 9). Whirling disease monitoring 

 continued near the mouth of Cottonwood Creek. The whirling disease results show a 

 continuous severe infection. We also completed related geomorphic and spawning site 

 surveys for Cottonwood Creek near the mouth (Results Part IV). 



,/ ^f ■, 

 Chamberlain Creek 



Restoration objectives: Improve access to spawning areas; improve rearing conditions for 

 WSCT; improve recruitment of WSCT to the river; provide thermal refuge and rearing 

 opportunities for fluvial bull trout. 



Project Summary 



Chamberlain Creek is a small Garnet Mountain tributary to the middle Blackfoot 

 River, entering at river mile 43.9 with a base flow of -2-3 cfs. Sections of lower 

 Chamberlain Creek were severely altered, leading to historic declines in WSCT densities. 

 Adverse changes to stream habitat included channelization, loss of insfream wood, 

 dewatering, streambank degradation from livestock, road encroachment, and elevated 

 instream sediment from road drainage. Other problems included fish losses to irrigation 

 ditches, impaired fish passage, and more recently the escalation of whirling disease in 

 lower reaches. 



Between 1990 

 and 1996, Chamberlain 

 Creek was the focus of 

 a comprehensive 



fisheries restoration 

 effort. Projects include: 

 road drainage repairs, 

 riparian livestock 



management changes, 

 fish habitat restoration, 

 irrigation upgrades 



(Consolidate ditches, 

 water conservation, 

 eliminate fish 



t^ eS^ c^ cc 



>* 



/ 



N**' 



5? cs<^ ^<5> ^ 



^"^ 



'V^^ 



Figure 20. CPUE for WSCT in Chamberlain Creek at mile 0. 1 , 1989- 

 2005 



31 



