Reconnect South Park
About this Project
Reconnect South Park is a partnership between us (OPCD) and community-based Reconnect South Park Coalition. We are working to enhance connectivity, economic opportunity, health, and environmental quality in the Duwamish Valley by rethinking State Route (SR) 99 and exploring how the corridor from South Holden Street to Tukwila International Boulevard could function in the future.
The Washington State Department of Transportation, which owns and operates SR 99, is an active technical partner. The work is coordinated with regional agencies through an Interagency Advisory Group that includes the Port of Seattle, King County, neighboring jurisdictions, and the Puget Sound Regional Council. This project is funded through City, state, and federal sources.
What's Happening Now?
We released a Potential Futures Analysis on June 22, 2026. The report compares four approaches to reimaging the corridor; Reroute and Reclaim, Narrower Boulevard, Wider Boulevard, and Bridges and Trails. These options are explored using 22 measures across five community-defined goal areas:
- Health and Well-Being
- Affordability and Economic Opportunity
- Mobility and Connectivity
- Healthy Environment
- Cost and Feasibility
Each approach offers a different balance of benefits and tradeoffs. The analysis is exploratory and non-binding. It does not recommend a preferred option, and no decisions have been made about the corridor's future. Read the executive summary for an overview or explore the full Potential Futures Analysis Report to understand the research and results.
Why We're Exploring This Corridor
This section of SR 99 running through the South Park neighborhood was built in the 1950s and 1960s. It was built diagonally across the neighborhood's street grid, creating 22 dead ends and leaving only a few safe ways to cross. Today, fewer than 10% of trips on the road start or end in South Park, and it is mostly used by regional traffic passing through. Four other major north-south routes also operate within a mile of this area. SR 99 sits immediately next to key community gathering spaces and community anchors, including Concord Elementary School, the South Park Branch of the Seattle Public Library, and the South Park Community Center. The Duwamish River flows within 20 feet of the road in some locations, affecting salmon and other critical habitats. Reconnect South Park is exploring how this corridor could be modernized to be safer, healthier, more connected, and beneficial to more people and places.
What's Next?
A coalition-led community visioning process will define what the corridor's future will look like, and result in a Community Vision Plan. This work is being done at the same time as more extensive traffic and freight study, and continued coordination with agency partners.
The project team will also develop strategies for community investment and stability so that current residents and businesses can thrive in place. This multi-year effort, developed with the South Park community, works to ensure that any future changes to the corridor support housing continuity and small-business stability.
Any future change to the corridor requires additional design and study, environmental review under state and federal law (NEPA and SEPA), coordination with WSDOT, and formal agency decision-making. Because of the scale of coordination involved, construction on any change is likely many years away.
This is a community-driven process, and community priorities have shaped it from the start. Since 2022, the Coalition has led engagement and outreach, connecting with thousands of neighbors, businesses, and organizations through hundreds of community events, surveys, small business interviews, and youth design workshops, and more.
The Coalition is now leading a community visioning process to shape the corridor's future, and your input will directly inform the Community Vision Plan.
To find upcoming events, take a survey, and learn how to get involved, visit the Reconnect South Park Coalition website and subscribe to receive South Park email updates.
Potential Future Analysis Report (June 2026)
Compares four approaches to the SR 99 corridor across 22 measures in five community-defined goal areas. A discovery tool: exploratory and non-binding, with no preferred option identified.
- Potential Future Analysis Report Executive Summary
- Read full Potential Future Analysis Report (Large 69mb file)
Reconnect South Park Storymap
The Reconnect South Park StoryMap is a visual, scrollable tour of the corridor today and the four potential futures.
Alternatives Review and Potential Fatal Flaws (May 2025)
The Potential Futures Definition Technical Memorandum: Considerations, Risks, and Potential Fatal Flaws screened the potential futures against infrastructure, environmental, regulatory, and operational risks. The review recommended dropping the tunnel option because of feasibility issues including utility conflicts, geotechnical and flood and seismic risks, and very high cost.