Halsey STP - Secondary Wastewater Treatment in Halsey, Oregon

Halsey STP is a municipal wastewater treatment facility located in Halsey, Oregon, a small community in Linn County. The plant serves a population of approximately 740 people, reflecting its role as a small-scale treatment operation within the state's wastewater infrastructure. The plant provides secondary treatment, a standard level required under the U.S. Clean Water Act for municipal facilities. With a designed capacity of 745.72 m³/day and an actual discharge volume of 378.54 m³/day, the plant operates well below its capacity, indicating room for future growth. As a U.S. facility, it operates under an EPA National Pollutant Discharge Elimination System (NPDES) permit issued by the Oregon Department of Environmental Quality, which sets effluent limits to protect water quality. The treated effluent from Halsey STP is discharged into a local waterway that ultimately drains into the Willamette River basin, a major tributary of the Columbia River. The Willamette River supports diverse aquatic life, including salmon runs, and is a critical water resource for the region. The plant's secondary treatment helps reduce organic pollutants and suspended solids, contributing to the ecological health of the downstream environment.

Halsey STP discharges into a local tributary of the Willamette River, which flows north to join the Columbia River before reaching the Pacific Ocean. The Willamette basin supports important fish species such as Chinook salmon and steelhead trout, making water quality management crucial. The plant's secondary treatment reduces biochemical oxygen demand and total suspended solids, helping to maintain the ecological integrity of the river system.