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Montana Water Quality Standards (MAC 16-2.14(10)-S13380) 



The Montana Water Quality Standards have been developed pursuant to the 

 Montana laws regarding water pollution. These standards classify all 

 waters in the state of Montana with respect to their quality and beneficial 

 uses. Most waters in Montana are classified as being suitable either as 

 a public water supply and for propagation and growth of salmonid fishes 

 or for use as a water supply and growth and propagation of non-salmonid 

 fishes. There are a number of other water quality categories with 

 suitability for aquatic life, irrigation, industrial water supply and 

 public water supply being the key in these classifications. 



The water quality standards establish maximum allowable changes in water 

 quality and establish limits for pollutants which affect the prescribed 

 beneficial uses of state waters. The rule specifies minimum levels for 

 dissolved oxygen, temperature, col i form bacteria, dissolved chemical 

 substances, toxic materials, radioactivity, turbidity, color, odor, and 

 other deleterious substances. In addition to specific water quality 

 requirements, these standards also have general water quality criteria. 

 These general criteria provide for short term exceedence of specific 

 water quality criteria due to necessary activities such as dredging, 

 channel or bank alterations, stream diversions or other construction 

 activities where turbidities may exceed the criteria. 



The standards for each classification of waters should provide for protection 

 and non-degradation of stream water quality (a draft of revised water 

 quality standards has been completed by the Water Quality Bureau). 

 Enforcement of the standards is discussed under the MWPCA. 



