East Marginal Way Corridor Improvement Project

Updated January 29, 2024

What's Happening Now?

We are preparing for construction of the North Segment and anticipate starting in early 2024! We will provide more information on the construction start date and schedule soon.

Stay connected

Visit our project library at the bottom of this page to read more about project features and schedule, view our federal grant proposals, and look at design plans. Comments and questions are welcome by emailing EastMarginal@seattle.gov or calling (206)257-2263.

Overview

As Seattle grows, improvements to freight mobility are essential to promote regional and international economic competitiveness. East Marginal Way is a major freight corridor that provides access to the Port of Seattle terminals, rail yards, industrial businesses, and between local Manufacturing and Industrial Centers (MIC's). It is also a designated Heavy Haul Route, critical last-mile connector, and vital route for over-sized trucks or those carrying flammable cargo. In addition, the corridor provides a major connection for people who bike between the West Seattle Bridge Trail, downtown, and the SODO neighborhood.

This project will:

  • Improve safety and reliability in the movement of people and goods

  • Support freight loads by rebuilding East Marginal Way S to heavy haul standards

  • Promote efficiency through signal modifications, improving wayfinding and lighting, and intelligent transportation systems

  • Improve safety by separating non-motorized modes of traffic from vehicle traffic  

Click here to view the latest design overview of the North Segment. The project reached final design in summer 2022 and we expect construction to begin as soon as early 2024.

Benefits

  • Safety - Improved access and multimodal connections for all corridor users. Separated facilities for people walking and biking to reduce potential conflicts.
  • Freight mobility - Support the economic vitality of our region by making it easier for freight to access the Port of Seattle and local industrial businesses.
  • Efficiency - New and updated facilities for people walking and biking will improve access for transit. Signal modifications and intelligent transportation systems (ITS) will optimize travel for all corridor users.

Project segments

This project extends along East Marginal Way S from S Atlantic St to 1st Ave S. The project is divided in three segments – North, Central, and South. Each segment is moving at its own schedule based on funding we have secured for design and construction. The North segment of the East Marginal Way S project is now designed and moving into construction. The Central Segment is funded for design and unfunded for construction. The South Segment is unfunded for design and construction.

Map showing 3 segments of the project

Select each segment below for more information about the design and schedule.

East Marginal Way Segments

North Segment

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

Graphic showing the location of the north segment

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

Map of existing conditions between S Atlantic St and S Massachusetts St

Planned improvements: S Atlantic St to S Massachusetts St

Map of planned improvements between S Atlantic St and S Massachusetts St

Existing conditions: S Hanford St to S Horton St

Map of the existing street configuration on East Marginal Way between S Hanford Street and S Horton Street

Planned improvements: S Hanford St to S Horton St

Map of the planned improvements on East Marginal Way between S Hanford Street and S Horton Street

Existing conditions: S Horton St to S Spokane St

Map of current conditions between S Horton St and S Spokane St

Planned improvements: S Horton St to S Spokane St

Map of planned improvements between S Horton St and 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.

Graphic of the Central Segment

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.

East Marginal Map South Segment
Click to enlarge

Benefits

Funding

Funding to evaluate alternatives and complete early design was provided by the 9-year Levy to Move Seattle, approved by voters in 2015. Learn more about the levy at Levy to Move Seattle website. In 2019, we secured grants from Transportation Improvement Board (TIB) and Federal Highways (FHWA) to complete full design for the north and central segments. In November 2021, we secured remaining grant funding to construct the North Segment of the project. North Segment funding partners include:

  • Freight Mobility Strategic Investment Board (FMSIB)
  • Transportation Improvement Board (TIB)
  • Port of Seattle
  • Federal Highways (FHWA) funds from PSRC and RAISE

We continue to look for funds for construction of the Central Segment and to advance the South Segment design. Opportunities include state funding for highways and for non-motorized facilities, FMSIB, and other local transportation packages.

Segment Design Funding Construction Funding
North Yes Yes
Central Yes No
South No No

Schedule

This project began in 2015 and has advanced project planning and design through consistent engagement with community members, businesses, partner agencies, and community advocacy groups. We have secured funding to construct the North Segment of the project and expect to begin construction as soon as early 2024. Construction of the Central and South Segments will depend on identifying funding sources.

Planning phase (2015 - 2016)

  • Data collection and preliminary traffic analysis

  • Early design workshops

  • Community engagement through online open house and survey

Design phase (2017 - 2023)

  • North Segment design - completed summer 2022

  • Central segment design - reached 90% design in summer 2023
  • Freight and bike community engagement survey

  • Briefings to community groups and bike detour workshop

  • Coordination with railroad agencies

  • Secured funds for North and Central Segment design and North Segment construction

Pre-construction of North Segment (2023)

  • Potholing to locate utilities
  • Ordered water main pipe
  • Outreach to businesses

Construction of North Segment (Expected 2024- 2026)

  • Expect to begin construction as soon as early 2024

  • Community outreach during construction

  • Expect to complete construction in 2026

Public Engagement

We are committed to keeping you informed and involved throughout this project. Your questions and comments are always welcome by sending us an email at EastMarginal@seattle.gov or calling (206) 257-2263. To request a briefing for your organization or for more information, please send an email to EastMarginal@seattle.gov.

Project Materials

If you need this information translated, call (206) 257-2263

Si necesita traducir esta información al español, llame al (206) 257-2263

如果您需要此信息翻譯成中文 請致電 (206) 257-2263

Transportation

Greg Spotts, Director
Address: 700 5th Ave, Suite 3800, Seattle, WA, 98104
Mailing Address: PO Box 34996, Seattle, WA, 98124-4996
Phone: (206) 684-7623
684-Road@seattle.gov

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The Seattle Department of Transportation (SDOT) is on a mission to deliver a transportation system that provides safe and affordable access to places and opportunities for everyone as we work to achieve our vision of Seattle as a thriving, equitable community powered by dependable transportation.