Lakeside wastewater treatment project up for review
Lakeside is seeking approval of upgrades and expansion of its wastewater treatment plant as it nears capacity.
The Department of Environmental Quality has issued a draft environmental assessment for improvements to the Lakeside County Water and Sewer District system, along with ground water pollution control system permits that would allow the facility to discharge treated wastewater into the ground. The state agency is taking comments on the project through Feb. 10.
“Lakeside’s wastewater system is nearing capacity and in need of expansion and improved treatment,” according to a notice by the Department of Environmental Quality. “The proposed facility meets a critical need especially as the number of nearby houses continues to increase.”
The environmental assessment evaluates any environmental impacts arising from the discharge permit and construction of the first phase of upgrades to the Lakeside wastewater treatment plant. Upgrades include constructing a facility to treat septage from septic systems in the Flathead Valley.
The total project, which includes the first phase under review by state and a second phase of work, is estimated to cost $26 to $30 million for design and construction. Funding for the first phase comes from federal and state grants and loans and is estimated at about $13.4 million.
The Montana Ground Water Pollution Control System would allow the district to discharge treated wastewater into groundwater via rapid infiltration basins, which are shallow earthen basins for the controlled infiltration of treated wastewater.
The state is authorizing Lakeside to move forward with construction necessary for treatment facility upgrades. Construction work necessary for the first phase of upgrades is set for 2025.
The state agency has determined that the project lacks significant adverse effects to the human and physical environment.
The district’s wastewater treatment system located on Larkin Lane in Lower Valley treats wastewater from the Lakeside area and Somers through an interlocal agreement. Growth within the district has result in increased flows, according to the Department of Environmental Quality’s environmental assessment, and has led the district consider facility upgrades since the existing treatment plant is “not sized to accommodate already committed and anticipated future connections.”
The treatment facility was originally constructed in 1988 and updated in 1994.
The current system does not discharge to state waters and operates by storing treated wastewater during the winter months and using land application during the agricultural season. The facility’s storage lagoon and irrigation site has limited the ability to accommodate increased wastewater or accept new connections.
Discharge to groundwater as authorized by the permit would not begin until the second phase of construction is complete. Additional approval for the second phase is required before the septage receiving facility can operate.
In addition, the first phase of construction will also include a force main to convey wastewater from the septage receiving facility to a new headworks facility at the existing Lakeside wastewater treatment plant and replacement of an existing wastewater lift station within the district’s collection system.
As part of the first phase, a new septage receiving and treatment facility would be constructed on the district’s existing land application site on Somers Stage Road near where it intersects with U.S. 93 South. The facility would include a septage unloading site where septage pumped from septic tanks can be disposed.
The facility would not be operational until the second phase when construction is complete for a specialized wastewater treatment facility to treat the district’s normal wastewater flows along with septage.
Flathead County commissioners in March 2024 entered into an agreement with Lakeside to construct and operate a septage treatment facility. The county is providing about $21.76 million in funding for the project including roughly $17 million in funding from the American Rescue Plan Act and grant funding from the state Department of Natural Resources and Conservation.
According to Flathead County, there are more than 24,000 permitted septic treatment systems within the county that require regular maintenance to pump septage from tanks. Traditionally the septage has been disposed of by land application, but due to significant development resulting in an increase in septics and a decrease in land application sites has resulted in a need for a better option, according to the environmental assessment.
The Department of Environmental Quality determined that the new facility would represent a new source of total nitrogen in the location. However, the wastewater and septage received and treated by the facility already exists in the Flathead Lake watershed and is currently treated to much lower standards. The project would therefore result in a “net reduction in the total nitrogen discharged in the greater watershed,” the analysis says.
To view documents related to the project and submit a comment visit: deq.mt.gov/News/publiccomment-folder/Extension-PN-MT-24-14-MTX000307
Deputy Editor Heidi Desch may be reached at 758-4421 or hdesch@dailyinterlake.com.