Columbia Blvd STP - Portland, Oregon Wastewater Treatment Plant

Columbia Blvd STP (Columbia Boulevard Wastewater Treatment Plant) is a large municipal facility located in Portland, Oregon, United States. Serving a population of over 720,000, it is one of the key wastewater treatment plants in the Pacific Northwest region. The plant operates under the regulatory framework of the US Clean Water Act, which requires secondary treatment for municipal wastewater. As a large facility serving a major urban area, it is subject to stringent National Pollutant Discharge Elimination System (NPDES) permits issued by the Oregon Department of Environmental Quality. These permits set limits on effluent quality to protect receiving waters. The treated effluent from Columbia Blvd STP is discharged into the Willamette River, which flows north through Portland and eventually joins the Columbia River. The Columbia River then empties into the Pacific Ocean. The plant plays a critical role in protecting the water quality of the Willamette River and downstream ecosystems, including salmon and steelhead habitats.

The plant discharges into the Willamette River, a major tributary of the Columbia River. The Willamette River supports diverse aquatic life, including several species of salmon and trout that are culturally and economically significant. The Columbia River basin is one of the largest watersheds in North America, draining into the Pacific Ocean. Protecting water quality in this system is essential for maintaining healthy fish populations and recreational uses.