Lakeside-Somers Wastewater Expansion Raises Concerns for Flathead Lake’s Water Quality
In the spring of 2025, the Flathead Lakers submitted comments to the Montana Department of Environmental Quality (DEQ) on the proposed expansion of the Lakeside Somers County Water and Sewer District’s wastewater treatment facilities. While we supported the need for improved infrastructure, we raised concerns about the chosen site, which sits only 10–20 feet above groundwater in soils with limited filtration capacity. Without additional safeguards, nutrients and emerging contaminants like PFAS could migrate quickly into Wiley Slough, Ashley Creek, and ultimately Flathead Lake.
Since then, the project has become a flashpoint in the community. A recently published op-ed in the Flathead Beacon urges DEQ to require the best available wastewater technology, not just incremental improvements, when Flathead Lake’s water quality is on the line. The Flathead Lake Biological Station also raised concerns about the expanded sewer treatment facility in a recent op-ed in the Daily Interlake. A distinguished Scholar at the University of Montana and Professor Emeritus at Flathead Lake Biological Station Ric Hauer created an educational video explaining how shallow groundwater and permeable soils could allow pollutants to reach the lake faster than predicted, and why transparent monitoring of nitrogen, phosphorus, and PFAS is essential.
Meanwhile, the financial implications are becoming clearer. In August, the Lakeside Water and Sewer Board voted unanimously to raise sewer rates to help cover costs of the project. Starting in September, ratepayers are seeing significant increases in their monthly bills, sparking frustration among many residents who question both the affordability and the adequacy of the proposed treatment system. Find out more here.
Legal challenges are also unfolding. Citizens for a Better Flathead and the Confederated Salish and Kootenai Tribes filed suit against DEQ, arguing that the agency approved a discharge permit without properly analyzing nutrient impacts. Their complaint points out flaws in DEQ’s groundwater modeling and warns that the facility could eventually release up to 900,000 gallons of effluent per day, nutrients that could worsen conditions in already impaired Ashley Creek and undermine Flathead Lake’s water quality. Read more at kpax.com.
The Lakers continue to advocate for strong safeguards for protecting water quality in the Flathead watershed. Flathead Lake is already under pressure from nutrient pollution, invasive species, and climate change. Any new wastewater project must be held to the highest standards to ensure we protect this irreplaceable resource for future generations.
Read the Lakers’ full public comments on the proposed Lakeside-Somers sewer expansion and why stronger safeguards are needed to protect Flathead Lake.