East Marginal Way Corridor Improvement Project

North Segment

The North Segment runs from S Atlantic St to S Spokane St. 

North Segment improvements will reduce conflicts between people biking and trucks accessing Port of Seattle driveways and increase safety and efficiency through the corridor. Design improvements include:

• Reconstructing the East Marginal Way S roadway to heavy haul standards from approximately S Massachusetts St to S Spokane St

• Protected bike lane separating non-motorized modes from freight traffic on the east side of East Marginal Way S between S Atlantic St and S Spokane St

• Multi-use path on the west side of the street between S Horton St and S Spokane St

• New signalized diagonal bicycle crossing at East Marginal Way S and S Horton St

• Rebuilding the intersection and existing traffic signal at East Marginal Way S and S Hanford St

• Revised curb radius with a truck apron at S Spokane St

• New bike crossing with rapid flashing beacon (RRFB) at East Marginal Way S and S Massachusetts St

• Replacing the existing water main in areas where the roadway will be reconstructed north of S Horton St

• Rebuilding the sidewalk on the west side of East Marginal Way S adjacent to the roadway reconstruction north of S Horton St

• Redesigning driveway at Terminal 25 South to improve visibility for people biking and driving

• Dynamic message sign at S Alaska St and East Marginal Way S

• Weigh-in-Motion system to help SDOT better understand wear and tear on our roadways and replace current spot-check enforcement system

The maps below show the current conditions and planned improvements between S Atlantic St and S Spokane St.  

Existing conditions: S Atlantic St to S Massachusetts St

Planned improvements: S Atlantic St to S Massachusetts St

Existing conditions: S Hanford St to S Horton St

Planned improvements: S Hanford St to S Horton St

Existing conditions: S Horton St to S Spokane St

Planned improvements: S Horton St to S Spokane St

Central Segment

The Central Segment run from S Spokane St and Diagonal Ave S. It is funded for design and unfunded for construction. We will continue to pursue funding opportunities to construct the Central Segment.

This project aims to upgrade the Heavy Haul network, provide a clear route through the confusing area between S Spokane St and Diagonal Ave S, and construct a shared use trail to separate people walking and biking from motor vehicle traffic.

Freight improvements proposed in the Central Segment include reconstructing the surface street of East Marginal Way S to heavy haul standards between S Spokane St and Duwamish Ave S, improving wayfinding and lighting, and a Weigh-in-Motion system for northbound traffic at Duwamish Ave S. At the intersection of Diagonal Ave S, this project plans to realign the southwest corner to improve the turning radius for eastbound trucks making a right turn.

Our proposed design includes a shared use path west of the SR-99 viaduct on the east side of East Marginal Way S south of S Spokane St. At approximately mid-block, the path will cross to the west side of the street at a marked crosswalk, where it will continue to Duwamish Ave S. People walking and biking will use a marked crosswalk with flashing beacons to cross Duwamish Ave S and continue on the west side of East Marginal Way S past the concrete plant. The project will continue a wide shared use trail south to Diagonal Ave S.

South Segment

The South Segment runs from Duwamish Ave S to 1st Ave S. It is unfunded for both design and construction. We will continue to pursue funding opportunities to advance the South Segment, but currently do not have a schedule for this portion of the project.

The South Segment, from Duwamish Ave S to 1st Ave S, is part of State Route 99. There are no existing bike facilities or sidewalks on the west side of the street and sections of missing sidewalks on the east side of the street.

In March 2018, we completed a preliminary design for the South Segment that included:

• Pedestrian improvements at each existing traffic signal
• Constructing missing sidewalks on the east side of the street
• Bus stop improvements
• Signal enhancements where appropriate to improve predictability and safety for people walking and biking

We also developed a proposal to improve pedestrian and bicyclist connectivity to the 1st Ave S bridge. Design and construction of the South Segment is currently unfunded. We will continue to pursue funding opportunities to advance the South Segment, but currently do not have a schedule for this portion of the project.

Click to enlarge