What is included in Stage 2?
The SR 509, 24th Avenue South to South 188th Street– New Expressway Project includes the following key features:
- Two miles of new SR 509 expressway between 24th Avenue South and South 188th Street [Des Moines/SeaTac]
- Reconfigured SR 509 interchanges at South 160th Street and South 188th Street [Burien/SeaTac]
- New South 192nd Street bridge over the new SR 509 expressway [SeaTac]
- SR 509 expressway bridge spanning park land and a stream south of South 200th Street [SeaTac]
- New southbound auxiliary lane on I-5 between the SR 516 interchange and South 272nd Street [Kent]
- Increased multi-modal access and safety features on local streets and trails [Burien/Des Moines/SeaTac]
- Two new noise walls near South 160th Street in Burien and extension of one existing noise wall alongside I-5 in Kent
- Retaining walls to minimize impacts to nearby wetlands and stream buffers
- Landscaping, wetland preservation, and environmental rehabilitation activities at Barnes Creek in Des Moines and within the SR 509 corridor in SeaTac
