Rock Creek Interceptor Extension Project

The Rock Creek Interceptor Extension Project was identified as a priority in the Capital Improvement Master Plan to ensure a safe, resilient, reliable sanitary sewer system with the capacity to serve our community now and in the future. This project will provide additional capacity and system improvements to serve Clackamas County and portions of the Happy Valley, Pleasant Valley, and North Carver Comprehensive Plan area.

Interceptor Defined

An interceptor is a primary sewer line that receives wastewater flow from several smaller trunk and local sewer lines. The interceptor moves the wastewater to the wastewater treatment facility. Interceptors are some of the largest pipes in a sewer system.

Project Location

The work includes extending the Rock Creek Interceptor beyond the intersection of SE 172nd Avenue and SE Troge Road to the north and east: 

• The north interceptor extension (in red) generally follows the Rock Creek tributary north to the Multnomah County border and includes approximately 9,800 linear feet of new sewer.  
• The east interceptor extension follows SE Troge Road to SE Foster and includes approximately 3,200 linear feet of new sewer.  
• The map included is the approximate location of the new sewer. Final alignment has not yet been determined and will take place during the design phase.

This project is dependent on downstream capacity upgrades being completed under the Clackamas Area Interceptor Improvement Project. See map including downstream projects.

Project Planning

One of the first tasks is to create a baseline of conditions 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. Geotechnical borings will also be taken. Property owners will be contacted before access is needed on private property.

This project is primarily within residential areas. 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 Rock Creek, wetlands, and stream crossings. The Rock Creek Extension 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 Master Plan.