SR 510 - Yelm Loop - New Alignment Phase 2

Project news

  • Phase 2 construction was funded by the 2015 Connecting Washington revenue package.


Why is WSDOT proposing to complete the SR 510 Yelm Loop?
State Route 510 is a two-lane highway that is often congested in the Yelm area during peak commute hours. Congestion can also be heavy when drivers are diverting around crashes or other incidents on I-5 and during the summer travel season.

SR 510 is the main street through Yelm. Heavy traffic congestion has the potential to negatively affect emergency response times and economic vitality.

This project would complete a bypass of the main commercial area of town, helping reduce congestion on Yelm Avenue and 1st Street South, improving traffic and freight mobility and reducing the potential for collisions.

The original timeline for this project had construction beginning in summer 2022. The project has been accelerated with the goal of starting construction in 2020. The accelerated timeline is due to unanticipated available funding combined with extensive preliminary work, such as environmental studies and preliminary design, conducted during the first phase of the project. In the first phase, WSDOT also purchased most of the right of way needed for this new portion of state highway.

Next steps: WSDOT is undertaking a Practical Solutions process to move forward on this project. WSDOT will re-engage stakeholders and take a fresh look at previous project plans. The fresh look will include reviewing the project’s purpose and need to ensure the proposed design is still appropriate and will provide intended benefits. The process includes evaluating traffic control at each intersection along the proposed alignment, and updating the project’s environmental documents.

The End Result
In this project, crews will build the 3 remaining miles of SR 510 between Cullens Road and 170th Street Southeast. The new connection, like the previously built Phase 1, is proposed to be a two-lane highway with bicycle and pedestrian facilities.

Project Benefits

  • Improving regional mobility on local roads and highways by providing a more efficient travel option.
  • Relieving traffic congestion and completing critical freight links.
  • The completed highway will allow traffic to move more efficiently between Thurston and Pierce counties.

What is the project timeline?

  • Spring 2018 - Stakeholder involvement 
  • Spring 2018 - Design work 
  • Summer 2018/Early 2020 - Environmental reevaluation
  • Summer 2020 (tentative) - Construction begins
  • Fall 2022 – Completed


Financial Data for PIN 351029A
Funding Source Amount ($ in thousands)
2003 Gas Tax (Nickel Funding) $0
2005 Gas Tax (TPA) $0
Pre-Existing Funds (PEF) $0
CWA $58,500
Total $58,500


How can I get more information?

Doug Adamson 360-357-2717
WSDOT Communications

Bill Elliott, 360-357-2735
WSDOT Project Engineer