
The City of Hillsboro currently has only one source of water—the Tualatin River. To secure a reliable additional source of water, Hillsboro partnered with Tualatin Valley Water District and the City of Beaverton to build the Willamette Water Supply System (WWSS).
The Cornelius Pass Road Pipeline Project is a 3.3-mile section of pipeline between Frances Street and just south of Highway 26. About 900 feet of this section of the pipeline will cross the northeast corner of Orenco Woods Nature Park (OWNP). Existing right of way is generally the preferred location for water pipelines. However, at this location, the TriMet bridge and Rock Creek bridge abutments across NE Cornelius Pass Road make it unfeasible to build the WWSS pipeline within the existing right of way. The east side of NE Cornelius Pass Road cannot be utilized for this construction because it is already developed with housing. The feasible location for this segment is through the eastern section of Orenco Woods Nature Park near Cornelius Pass Road.
The need to route the pipeline through the park was anticipated during park development. The City of Hillsboro’s OWNP 2015 land use approval required a utility easement for the future WWSS pipeline construction. Since 2017, the Willamette Water Supply Program (WWSP) has been in communication with Metro and City of Hillsboro Parks and Recreation staff to discuss the easement and its ultimate limits.

Project Updates
The Orenco Woods Nature Park Wildlife Protection and Adaptive Management Plan - Related Documents Library
- Washington Department of Fish and Wildlife: Integrated Streambank Protection Guidelines
- Washington State Aquatic Habitat Guidelines Program: Stream Habitat Restoration Guidelines
- WWSP Preliminary Design: Environmental, Land Use and Cultural Resources Review
- Wetland Delineation Report: WWSP Cornelius Pass Pipeline Project (PLW 2.0)
- Conceptual Post-Construction Site Restoration Plan
- Application to Clean Water Services for Programmatic Master Service Provider Letter
- Orenco Woods Nature Park: Master Plan Report
- Development Review 012-15: Orenco Woods Crossing Nature Park. Order No. 8154
- Orenco Woods Savannah Restoration Plan
- Orenco Woods Nature Park: Site Conservation Plan
- City of Portland Environmental Services: Protecting Nesting Birds
- Oregon Metro: Wildlife corridors and permeability
- Permit NWP-2015-0041
- Biological Opinion and Incidental Take Statement. WCR-2017-7795
- Removal/Fill Permit. 60102-RF
- Service Provider Letter. 18-000921
- Water Quality Certification. 2015-00041