Parma Sewage Lagoon - Secondary Wastewater Treatment in Canyon County, Idaho

Parma Sewage Lagoon is a municipal wastewater treatment facility located in Canyon County, Idaho, serving a population of approximately 1,983. The plant operates as a lagoon system providing secondary treatment, a common approach for small communities in the region. With a designed capacity of 2,574.07 million gallons per year and an actual discharge volume of 492.10 million gallons, the plant operates well below its capacity. As a US facility, it falls under the Clean Water Act's National Pollutant Discharge Elimination System (NPDES) permitting program, which sets effluent limits to protect water quality. The plant's treated effluent is discharged into local waterways that ultimately drain into the Snake River basin, a major tributary of the Columbia River. The Snake River supports diverse aquatic life and is an important resource for irrigation, recreation, and hydropower in the Pacific Northwest.

The plant discharges into the Snake River basin, which flows through southern Idaho and joins the Columbia River in Washington. The Snake River supports critical habitat for salmon, steelhead, and other native fish species. Downstream waters are used for agricultural irrigation and municipal supply, making nutrient and pathogen control important for protecting both ecological and human uses.