Gervais STP - Secondary Wastewater Treatment Plant in Gervais, Oregon

Gervais STP is a municipal wastewater treatment facility located in Gervais, Oregon, a small city in Marion County. The plant serves a population of about 2,080 residents, reflecting its role in managing domestic wastewater for a small community. As a secondary treatment plant, it provides biological treatment to reduce organic pollutants and suspended solids before discharge. The plant has a designed capacity of 567.81 thousand gallons per day and currently treats an average daily flow of 264.98 thousand gallons per day, operating well within its capacity. Under the U.S. Clean Water Act, facilities of this scale are typically regulated through National Pollutant Discharge Elimination System (NPDES) permits issued by the Oregon Department of Environmental Quality, which set effluent limits to protect water quality. The treated effluent from Gervais STP is discharged into a local water body that ultimately drains into the Willamette River, a major tributary of the Columbia River. The Willamette River basin supports diverse aquatic life, including salmon and steelhead, and is an important ecological and economic resource for the Pacific Northwest. The plant's operations contribute to maintaining water quality in this sensitive watershed.

Gervais STP discharges into a local stream that flows into the Willamette River, which then joins the Columbia River before reaching the Pacific Ocean. The Willamette River basin is a critical habitat for several fish species, including Chinook salmon and steelhead trout, and supports a rich riparian ecosystem. The plant's secondary treatment helps reduce nutrient and pollutant loads, protecting downstream water quality and aquatic life.