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Middle Missouri River Basin 



7. Main Stem Missouri River Drainage 



This segment of the Missouri River drainage extends from Three Forks, 



Montana to the mouth of the Marias River near Loma, Montana. The DNR&C 



drainage basin designations included under this section are 411, 41QJ, 



and 41Q. Water quality classifications (DHES) gradually degrade from 



B-Di to B-D3 in this watershed segment. 



Fores tl and ownership is dominated by the USFS; however, there is also 

 significant private timberland ownership, including: Burlington Northern, 

 Champion, and severaT large ranch companies. Silvicultural activities 

 have been pursued in many areas; related water quality impacts are 

 outlined in Table VI-C7 and located on Plate I . Some water quality 

 impacts are minimized due to the dry climatic conditions. However, 

 other impacts may be aggravated due to slow regeneration rates on some 

 sites. 



Of particular interest are Conservation District estimates of commercial 

 forestland contributions to non-point sediment pollution. Belt Creek 

 and the Smith River are adjacent watersheds, however, their sediment 

 contributions are radically different: Belt Creek yields sediment 

 pollution from 40 percent of its forestland. Smith River yields sediment 

 pollution from only four percent of its commercial forestland. This 

 difference is probably due to natural characteristics of the basins 

 (soft shale and siltstone sediments and Tertiary volcanics), as well 

 as degree of other management activities (USFS logging, agriculture, 

 etc. ). 



