Regional Septage Treatment Facility

A septage treatment facility is a solution to preserve environmental quality and address population growth within our community. Flathead County has an estimated 40,000 wastewater treatment systems currently in place, with predicted continued growth to occur in the upcoming years. The increasing number of septic systems, in addition to the dwindling amount of available land for current septage disposal methods, has created a problem that could negatively impact the environment and our groundwater in the valley. A septage treatment facility will accept and treat septage and portable restroom waste, providing a solution to this growing disposal problem.

The proposed septage treatment facility will be the first of its kind in Montana.  

A wastewater treatment system is a system that is used to treat, or reduce contaminants, from wastewater that has been discharged from a home or business.  The treated water, or effluent, is then discharged back into the receiving environment. A WWTS is commonly referred to as a drainfield.  Septic tanks are an important part of on-site wastewater treatment systems, and they provide primary treatment of the wastewater before it is discharged into the groundwater. Over the years organic and inorganic solids and some liquid, also known as septage, accumulates in the septic tank and must be removed every 3-5 years to prevent from overfilling and passing this undesirable material into the drainfield which may cause catastrophic failure of the system. Septage pumped from septic tanks is currently disposed of through land application. Once the septage treatment facility is operational, septic pumpers will have another disposal option.

The local wastewater treatment plants located in Whitefish, Kalispell, and Columbia Falls are required to meet strict effluent limits and and as a result utilize sensitive biological treatment processes.  Septage, which is a very high strength waste, can easily upset these treatment processes resulting in an exceedance of effluent limits which is a violation of State law. Therefore, the area municipal treatment plants are unable to accept septage from surrounding septic tanks. As a result, septage in Flathead County is currently disposed of through land application which includes injecting the untreated septage into the soil.

Discussions of a solution for septage disposal and treatment has been ongoing for several years due to the population growth of our county and the limited availability of land for land application purposes. This project came together as a collaborative effort between the Flathead County Health Department, the cities of Kalispell, Columbia Falls, and Whitefish, Evergreen Water and Sewer District and the Lakeside County Water and Sewer District. Flathead County has been actively working on this project for two years, since project funding became available through the American Rescue Plan Act (ARPA). 

The facility will be located on property owned by Lakeside County Water and Sewer District (LCWSD) in the lower valley. LCWSD is currently working with their project engineer to finalize the facility design and location.

Flathead County originally purchased property at 305 Wiley Dike Road with the intent of building and operating a septage treatment facility at that location. After further due diligence, the County signed a new Interlocal Agreement with Lakeside County Water and Sewer District, where the County would provide funding but LCWSD would build, own and operate the facility. 

A Resolution of Intent to sell the property at 305 Wiley Dike Road to Lakeside County Water and Sewer District for furtherance of their wastewater treatment operations is scheduled for Commissioner consideration on March 28, 2024. 

Construction is scheduled to be complete by December 31, 2026. Lakeside County Water and Sewer District will build, own, and operate the facility.

Lakeside County Water and Sewer District is currently working with DEQ to obtain the proper project permits. Flathead County is closely monitoring LCWSD's permit application process. Both parties are optimistic about the permit's approval. In the unlikely event that the permit is not approved, the invested funding is refundable.