Sewage from Oregon City, West Linn and Gladstone arrives to the Tri-City Water Resource Recovery Facility (WRRF) through a large pipe approximately 40 feet underground. In order to treat the incoming flow through the facility, the Influent Pump Station (IPS) pumps the flow up to ground level for subsequent flow through the treatment process. The IPS was originally constructed in 1985 and was sized to pump up to 50 million gallons per day. However, in recent years the pump station has been operating beyond its firm capacity during some winter wet weather events, meaning all five pumps and supporting equipment must be in service in order to pump flow that arrives to the plant during those storms. A major capital upgrade is needed to both expand the capacity of the facility and replace obsolete equipment.
Location
The Tri-City WRRF is a regional treatment plant located in Oregon City that serves customers in Gladstone, Happy Valley, Milwaukie, Oregon City, West Linn and unincorporated Clackamas County. Learn more about the Tri-City WRRF.
Project Planning
The recently completed Willamette Facilities Plan charted the path forward for the Tri-City WRRF through the year 2040. As part of the recommended improvements, the immediate need to pump more flow and to accommodate growth was identified for the IPS. Given the urgency for additional capacity, a project was initiated to address the IPS ahead of the future Wet Weather Expansion outlined in the Willamette Facilities Plan.
In the Summer of 2022, a Request for Proposals was issued to recruit an engineering design team for the project. Design will occur in 2023 through 2024, with construction anticipated to follow. All construction activity will occur on the site of the Tri-City WRRF and no public disruptions are anticipated.