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1. Big Hole River Drainage 



The Big Hole River drains a large portion of southwest Montana. The 

 watershed is defined by the Bitterroot Range to the west, the Anaconda 

 Range to the north, and the Pioneer Mountains to the south (which the 

 river skirts around). The Big Hole River, part of the Missouri River 

 drainage, flows into the Jefferson River near Twin Bridge, Montana. 

 The DNR&C drainage basin identification number is 41D. The drainage 

 is classified as A-Open-Di above the town of Divide, Montana, and as 

 B-Di from Divide to the mouth. 



Although most timberland in the area is under USPS administration, there 

 is also private. State, and BLM ownership of merchantable timber. Timber 

 harvesting on non-USFS lands is relatively small scale. The principal 

 management objective on private ownerships in this area is to increase 

 grazing capacity. Under this situation, timber regeneration is discouraged. 



Most timberland in this area is moderately sloping with dry soils; there- 

 fore, impacts to water quality have been minimal (USPS - Wise River, pers. 



comm.). The five Conservation Districts in the Big Hole drainage have 

 estimated that less than five percent (26,260 acres) of the commercial 

 forest land can be considered as contributing to soil erosion and non- 

 point water pollution (1977); over 50 percent of these problems are con- 

 sidered correctable. Although impacts to water quality have not been 

 monitored, poor harvesting practices have been observed or reported 

 (USPS - Viisdom, pers. comm.; USPS - Wise River, pers. comm.; DHES, 1974). 

 Such practices include skidding across stream channels, leaving debris 

 in streams, cutting adjacent to streams, and poor sizing of cutting 

 units (too large). In some of the dry areas, such practices may not 



