Bigfork County Water and Sewer District - Advanced Wastewater Treatment in Bigfork, Montana

Bigfork County Water and Sewer District is a wastewater treatment facility serving the community of Bigfork in Flathead County, Montana, United States. The plant treats wastewater for approximately 2,980 residents, reflecting a small to medium-sized agglomeration typical of rural Montana communities. The facility employs advanced treatment processes, exceeding the secondary treatment standard required by the U.S. Clean Water Act. With a designed capacity of 3,785.40 cubic meters per day and an average discharge volume of 787.37 cubic meters per day, the plant operates well below its capacity, indicating room for future growth. As a U.S. facility, it operates under a National Pollutant Discharge Elimination System (NPDES) permit issued by the Montana Department of Environmental Quality, which sets effluent limits to protect water quality. The plant's treated effluent is discharged into the local watershed, which ultimately drains into Flathead Lake, one of the largest natural freshwater lakes in the western United States. Flathead Lake is part of the Columbia River Basin and supports diverse aquatic life, including native trout species. The advanced treatment helps protect this ecologically sensitive lake from nutrient pollution and other contaminants.

The plant discharges into the Flathead River system, which flows into Flathead Lake, a large natural lake in northwestern Montana. Flathead Lake is a critical habitat for native fish species such as bull trout and westslope cutthroat trout, and it supports a vibrant recreational economy. The lake drains into the Clark Fork River, then the Pend Oreille River, and eventually the Columbia River, which reaches the Pacific Ocean. The advanced treatment level helps minimize nutrient loading and protects the lake's oligotrophic status, which is sensitive to phosphorus inputs.