1. STREAM 

 Oregon Creek 



2. DESCRIPTION 



Oregon Creek originates on the east slope of the Anaconda-Pintl ar 

 Range at the Continental Divide and flows in a southerly direction for about 

 1.2 miles to its mouth on California Creek. It meanders through a very small 

 floodplain and is bordered by a narrow riparian zone. Streamside vegetation 

 is composed primarily of grasses and sedges with small clumps of willow and 

 alder scattered intermittantly. Coniferous growth is extremely sparse 

 throughout the 1.8 square mile drainage and streamside canopy is restricted 

 to willow clumps or is lacking. The lower reaches of the stream are bordered 

 by till from a placer mining operation. The drainage is characterized by high 

 open south-facing slopes. Oregon Creek has no major tributaries. The average 

 gradient of the 7.5 foot wide channel is 31.6 feet per 1,000 ft. Ownership 

 of the Oregon Creek drainage is held entirely by the MDFWP. 



Recreational uses of the Oregon Creek drainage include hunting, fishing 

 and snowmobi 1 ing. No estimate of fishing pressure is available for Oregon 

 Creek and no fisherman use was observed during the summer of 1980. The 

 drainage has been used in the past for commercial livestock grazing, timber 

 harvest (Newell 1980), and placer gold mining (Lyden 1948). Present commercial 

 use of the drainage is confined to cattle grazing. 



Water chemistry samples were collected from Oregon Creek during the 

 summer of 1980. Chemical data indicated that Oregon Creek is a calcium- 

 sodium-bicarbonate water of moderate specific conductance, alkalinity and 

 hardness. Water quality was generally good except for the presence of 

 elevated levels of arsenic (average 24.9 ug/1) and lead (.08 mg/1). The 

 probable source of the arsenic is the Anaconda Smelter. Other existing 

 environmental problems include sedimentation from the slumping roadbed of 

 Highway 274 and channel and streambank alteration from past placer mining 

 acti vi ties. 



3. FISH POPULATIONS 



A 1,000 foot section of Oregon Creek was electrofished on August 5 and 

 August 14, 1980. Game fish captured in descending order of abundance were 

 brook trout and rainbow trout. Mottled sculpins were the only nongame species 

 present. Electrofishing survey data is given in Table 14. 



Table 14. Summary of electrofishing survey for a 1,000 foot section of 



Oregon Creek (T3N, RllW, Sec. 20C) on August 5 and August 14, 1981. 



Species No. Captured Length Range (inches) 



Brook Trout 275 2.5-11.1 



Rainbow Trout 4 4.6-8.3 



Mottled Sculpin 



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