Willamette Pump Station and Force Main Capacity and Condition Improvements Project

Clackamas Water Environment Services (WES) owns and operates the pump station and force main carrying wastewater from West Linn to our water resource recovery facilities. The existing Willamette Pump Station and Force Main, which were constructed 1986, have served the West Linn community well. However, improvements and upsizing are needed for WES to continue to provide a resilient, reliable sanitary sewer system to serve our community now and in the future. Pump stations are a vital part of our infrastructure that need to be operational 24 hours a day 365 days a year, pumping sanitary sewage safely through the collection system to our water resource recovery facilities for treatment.

The Willamette Pump Station and Force Main Capacity and Condition Improvements Project will replace the existing pump station with modern, more reliable, and efficient pumps and will allow us to be better prepared for emergencies by raising the critical equipment and access points above flood level. In addition to upgrading the pump station, this project will include a new, more resilient force main and gravity fed sewer line with an updated alignment that will increase capacity and help prevent overflows and improve the overall operation of the system. 

What is a pump station?

Pump stations are used to help transport fluids from one point to another. They play an integral role in sanitary sewer collection systems. Our sewer system relies on pump stations, or lift stations, to push wastewater from point A to point B, especially in cases where gravity can’t move flow from a low-lying area to higher ground. 

What is a force main?

A force main is a pressurized sanitary sewer pipe. Force mains are used where gravity is insufficient to move wastewater through a sewer line. 

What is a gravity sewer pipe?

A gravity sewer pipe is a sewer line that utilizes the energy resulting from a difference in elevation to move wastewater through the sewer system—generally to a pump station or ultimately to a treatment facility where it can be cleaned and discharged back into a river. 

Project Location

The Willamette Pump Station updates will be constructed at 1001 4th Street in West Linn. Additionally, the upgraded force main and gravity pipeline will be constructed along Willamette Falls Drive and connect to the broader system near the West Linn I-205 on-ramp. 

Project Planning

One of the first tasks is to create a baseline of conditions in the project area and along the pipeline route. Field crews will be surveying land, locating utilities, identifying potential environmental, cultural, and historic resources to protect, and assessing the topography, soil, and geology. Most of the work will be on WES-owned property or within the public right-of-way. Property owners will be contacted before access is needed on any private property.

This project is within the primarily residential West Linn community. Maintaining access to private properties is essential. We will coordinate with neighbors, local businesses, agencies, and service providers in the area.

This project includes sensitive environmental areas, including the Willamette River. Willamette Pump Station and Force Main Capacity and Condition Improvements Project will seek to minimize potential impacts to fish and wildlife habitats during design and construction. 

Community members, the WES Advisory Committee, industry experts, and elected officials provided vital input to prioritize this project as part of the Capital Improvement Plan.


150 Beavercreek Road #430, Oregon City, OR 97045

Office Hours:

Lobby hours
Monday to Thursday
7:30 a.m.–noon and 1–5 p.m.

Phone hours
Monday to Thursday
7:30 a.m.–noon and 1–5 p.m.

Customer service

Development services and permits

Related Events
Water Environment Services
Water Environment Services
Water Environment Services
Related News
Water Environment Services, Transportation and Development, Parks, North Clackamas Parks and Recreation
Public Health, District Attorney, Water Environment Services