172nd Ave Infrastructure Improvements
Re-designing the roadway to improve safety and connectivity for pedestrians, cyclists, and motorists along SE 172nd Avenue.

Thank you for visiting the virtual open house. You will find general information about the project, concept design exhibits, a project timeline and more below. Please complete the comment form at the end to submit comments or ask questions.
Project Overview
The proposed infrastructure improvements within the 172nd Ave corridor will reduce congestion, increase safety and connectivity, and help prepare Happy Valley, Pleasant Valley, Carver and Gresham for expected population growth. The street is a main road in the area and these improvements have been prioritized in the transportation plans for the City of Happy Valley and Clackamas County for many years. Improvements are coming to the area between Misty Dr and Scouters Mountain Road.
The City of Happy Valley is assisting in project coordination and review. The county is managing and leading the design and construction activities.
Improvements Include:
- Widening the roadway to four travel lanes
- Adding a separated bike and pedestrian path
- Constructing curb ramps to comply with Americans with Disability Act requirements
- Enhancing pedestrian crossings at 172nd Ave/Troge Road and Scouters Mountain Road
- Constructing a frontage road on the west side of 172nd Ave between Troge Road and Hagen Road
- Constructing a traffic signal or roundabout at 172nd Ave and Troge Road
- Widening Troge Road to add new bike lanes and sidewalks between 172nd Ave west and Olympic St
- Adding a new lane to the roundabout at Scouters Mountain
- Moving utilities underground
- Adding street lighting
- Building drainage and detention facilities
- Planting landscape areas including street trees and center medians
- Constructing up to two new culvert or bridge structures along Rock Creek under Troge and SE 172nd Ave
- Relocating Rock Creek and adding native plantings
Project Area
Existing Conditions
Proposed Typical Sections
Entire Design
Intersection Configuration Options
Alternative 1A - Standard Signalized Intersection at Troge
Close up view of Alternative 1A intersection below:
Swipe left to see the proposed changes for Alternative 1A.
Alternative 1B - Shifted Signalized Intersection at Troge
Close up view of Alternative 1B intersection below:
Swipe left to see the proposed changes for Alternative 1B.
Alternative 2 - Roundabout at Troge
Close up view of Alternative 2 intersection below:
Swipe left to see the proposed changes for Alternative 2.
Schedule
We expect engineering design, permitting and right of way acquisitions to be complete by the end of 2026, with construction scheduled for 2027 and 2028. The estimated schedule is shown below, but may change for a variety of reasons:
- Design: March 2023 to Winter 2026
- Right of way: Summer 2024 to Winter 2026
- Construction: Spring 2027 to Winter 2028
Funding
The $30 million project is paid for by the City of Happy Valley and city/county Transportation System Development Charge Joint District Funds. Clackamas County owns and maintains 172nd Ave, and is managing and leading the design and construction activities. The City of Happy Valley is assisting in project coordination and review.
Right of Way Process
There are times when Clackamas County must acquire right of way over private properties to improve existing roads or construct new roadway facilities. A right of way is an easement which grants the county access to a portion of private property for public use. It is the county’s policy and practice to obtain right of way with fairness and equity.
The county is empowered to acquire private property for public use. With this authority goes the obligation to protect the rights of individual property owners. The county has a dual responsibility to recognize and protect individuals who are directly affected by acquisition of land, and to provide competent and efficient services to the public as a whole.
We estimate 49 properties in the project area will require right of way acquisitions. As the project enters the right of way phase, county representatives or the right of way consultant (Epic Land Solutions) will reach out to each affected property owner.
All right of way acquisitions are conducted as required by state and federal law. Read about the right of way acquisition process.
Questions or concerns? Provide your information in the comment section to start a conversation with our team.
Environmental Protection
We will proactively reduce any impacts associated with the construction of the project near Rock Creek. Environmental protections for this project include:
Improving Wildlife Access
Rock Creek flows under the Troge Road/172nd Ave intersection. The small bridges that carry Rock Creek near this intersection will be removed and replaced with one or two wider culverts. The culvert(s) will carry Rock Creek and will also serve to provide fish and wildlife passage.
Conserving Wetlands
We will reconstruct portions of the Rock Creek channel to be able to remove the existing bridges and install new culverts along Rock Creek. Additional environmental protection measures include monitoring wetland and habitat conservation areas, and may include preserving vegetation or planting new vegetation near Rock Creek.
Developing New Flood Plain Plans
The improvements and modifications will impact the flood plain along Rock Creek. We will follow the Federal Emergency Management Agency’s process to remap the new flood plain and the county flood plain management requirements.
Improving Drainage, Water Quality, and Habitat
Right now, rainfall carries sediment and pollutants directly to Rock Creek. We will improve water quality and the drainage system in the Rock Creek Basin by filtering and cleaning the water before reaching Rock Creek to create better habitat for fish and wildlife.
Community Feedback
Open House and Public Comment
Clackamas County hosted a virtual online open house from February 22, 2024 to March 29, 2024. In addition, an in-person open house was hosted at Happy Valley City Hall on February 22, 2024. Project staff will respond to any questions or concerns for those who requested to be contacted.
Stay Connected
To sign up for the email list and be notified of future feedback opportunities and construction scheduling for this project, visit the project webpage and scroll down to the bottom to enter your email address.
For questions about the project, please contact the Clackamas County Project Manager, Jonathan Hangartner at jhangartner@clackamas.us .
Thank you!