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Missoula City-County Health Department
(406) 258-4755
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Health Division: Environmental Health
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Environmental Health

Land Services: Individual/Shared Septic Systems

One important potential source of contamination is sewage. In the larger community settings of Missoula County, wastewater treatment plants are used to treat the sewage before the treated sewage is released back into the river. But not all of Missoula County's areas are served by wastewater treatment plants. Many homes in the county have on-site wastewater disposal systems that dispose of sewage into the ground. Gradually that sewage, if not properly treated, can contaminate our groundwater, which is also the source of our drinking water.

Our Health Department has worked very hard to prevent contamination of our underground drinking water sources. You can find out more by visiting the Water Quality website.

The State of Montana also regulates individual septic systems. The document that spells out the state requirements is called DEQ Circular 4. (WARNING: This document takes several minutes to load.)

Alternative Septic Systems

Occasionally, there arises a case where a conventional on-site septic system is not appropriate for a particular piece of land. It might be because there is high groundwater, a steep slope or a well or irrigation ditch too close to the proposed drainfield location. Whatever the reason, there may be an option for the property owner in the Approved Alternative Systems Manual.

Have questions?  Contact us at 258-4755, or see our directory.


Liquid Wastes

Liquid waste, also referred to as sewage, black water and grey water is regulated at both the County and State level.   Missoula County Board of Health regulates sewage with Health Code Regulation 1.  Montana Department of Environmental Quality has several regulations for liquid waste:

Forms - Individual Septic Systems

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