Assessments of Best Management Practices 



pacts by ownership. 



The impacts have been summarized by the 

 major categories of BMPs identified on the 

 audit form.The "Timber Harvest" category, 

 which represents 1 1 of the 39 practices audited, 

 contributed the greatest number of potential 

 impacts to water quality — more than 30 per- 

 cent of all impacts, both "major" and "minor," 

 came from this one category alone.Most of 

 these deficiencies were associated with prac- 

 tices in the Streamside Management Zones 

 (SMZs) and with the location and drainage of 

 skid trails. 



The "Road Drainage" category involved 

 five of the 39 practices audited, but accounted 

 for more than 20 percent of all "major" and 

 "minor" impacts observed. Figure F-3 shows 

 the percentage of impacts as they were distrib- 

 uted by BMP category and by ownership. 



The Montana Department of State Lands' 



timber sales were the only ones on which major 

 impacts were not observed.Major impacts were 

 most often found on the Private Non-Industrial 

 sales, and 40 percent of their sales had at least 

 one major impact. The Flathead National Forest 

 and Plum Creek Timber Co. rated very simi- 

 larly with approximately 14 percent and 16 

 percent of their sales, respectively, registering 

 at least one major impact. 



This assessment included the same set of 

 BMPs that were audited in the 1988 EQC field 

 study, as well as additional or amended prac- 

 tices added to the audit form as a result of 

 adopted changes in the BMPs resulting from the 

 House Joint Resolution 49 report (1987 Legis- 

 lature). Most of those changes involved im- 

 provements of practices associated with stream- 

 side management zones, including minimum 

 SMZ width criteria.This practice was evaluated 



-/. OF IMPACTS BV BHP CATXGORV 



3B 



Koad Plan Drainage Constpuct. Main ten. 



Harvest 



Slash 



■■ Small Private E^?gJ Plum Creel< 

 d} All 



EZD USPS 



R\q 8tote Lands 



Figure F-3: Percentage of impacts by BMP category 



Flathead Basin Cooperative Program Final Report 



Page 85 



