Tri City WPCP - Oregon City, Oregon Wastewater Treatment Plant

Tri City WPCP is a wastewater treatment plant located in Oregon City, Oregon, serving a population of approximately 141,676. The facility is situated in Clackamas County and is part of the regional wastewater infrastructure for the Portland metropolitan area. As a large agglomeration, the plant is subject to the US Clean Water Act and EPA NPDES permit requirements, which mandate secondary treatment and, in sensitive areas, additional nutrient removal. The plant's treatment processes and capacity are designed to meet these federal and state standards, ensuring compliance with discharge limits. The plant discharges treated effluent into the Willamette River, which flows north to the Columbia River and ultimately to the Pacific Ocean. The Willamette River supports diverse aquatic life, including salmon and steelhead, making water quality protection critical for downstream ecosystems.

Tri City WPCP discharges into the Willamette River, a major tributary of the Columbia River. The Willamette River basin supports a variety of fish species, including threatened salmon runs, and provides habitat for wildlife. The plant's discharge must meet strict water quality standards to protect these downstream ecosystems and recreational uses.