The Montana Department of Environmental Quality has found no significant impact would result from planned upgrades and expansion of the Lakeside wastewater treatment facility. 

The state agency has set a public hearing on the draft environmental assessment for the second phase of the project for April 23 from 5 to 7 p.m. at the Lakeside Quick Response community room. The public comment period will end the same day at 11:59 p.m.  

Lakeside County Water and Sewer District is seeking approval of plans to construct and operate a new wastewater treatment facility. The draft assessment examines the environmental impacts of the new wastewater treatment facility, as required by the Montana Environmental Policy Act.  

The state agency found that the new facility would improve wastewater treatment by reducing nutrient loading to groundwater and surface water through higher-level treatment and create centralized septage management that hasn’t been available in Flathead County. 

The current wastewater treatment facility was constructed in 1988 and updated in 1994 and 2010 but is nearing capacity due to population increases. In August 2025, the District voted on three options for the new sewer treatment plant selecting a sequence batch reactor, which board members felt balanced construction and operational costs with treatment quality when compared to the other options.  

The environmental assessment evaluates the direct, secondary, and cumulative impacts that may result from Phase II, which includes approval of plans and specifications for the wastewater treatment facility and rapid infiltration basin systems, according to the draft assessment. These impacts include construction and operation of the facility, human health and safety, and cumulative impacts related to the additional treatment capacity. 

The scope of the environmental assessment is limited to the second phase. The first phase, which was approved April 9, 2025, concerned a permit that would allow for an update and expansion of Lakeside’s wastewater treatment facility to accept, treat, and handle wastewater and discharge treated wastewater into state groundwater via rapid infiltration basins, which are shallow earthen basins designed to allow treated wastewater to filter into the ground. 

As part of the first phase of the project, a new septage receiving and treatment facility is being constructed on Somers Stage Road, with expected completion in summer of 2026. The facility would not be operational until the completion of the second phase of the project, when the specialized wastewater treatment facility is finished to treat the district’s normal wastewater flow, along with septage from septic tanks.  

Lakeside entered into an agreement with Flathead County in 2023 to operate a regional septage treatment facility. There are 24,000 permitted septic systems that require regular pumping in the county, but no facilities that treat septage.  

Watchdog group Citizens for a Better Flathead called for the state agency to extend the public comment period to 60 days. The public comment period runs for two weeks ending on April 23.  

“This extension is vital to allow the public necessary time to hire independent experts to review the DEQ's proposal," said Co-Executive Director Mayre Flowers in a statement "Without it, the community is being denied the opportunity to provide informed and meaningful feedback on a project of immense public importance." 

The group has filed lawsuits against the Lakeside Water and Sewer District and the Department of Environmental Quality regarding the first phase of the project.  

In the draft environmental assessment, several impacts were examined. The agency expects the impacts of Phase II to be short-term and minor during construction and negligible to minor during operation. 

According to the draft, the wastewater treatment facility is expected to “reduce overall nutrient loading to groundwater and connected surface waters by providing higher‑level treatment, centralized septage management, controlled subsurface discharge, and higher quality effluent to the existing irrigation site” when compared to the existing facility.  

The public hearing will be held from 5 to 7 p.m. at the Lakeside Quick Response Unit, 201 Bills Rd, Lakeside. The state agency is accepting public comments on the draft environmental assessment through April 23. 

To view the environmental assessment, learn how to submit a comment, or for more information about attending the public hearing in person or virtually, visit deq.mt.gov/News/publiccomment-folder/lakeside-ea-04-09-26.

Reporter Elsa Ericksen can be reached at 406-758-4459 or [email protected]. If you value local journalism, pledge your support at dailyinterlake.com/support.