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23rd Avenue Corridor Improvements Project

Updated May 21, 2015

Phase 1 Construction | Current Schedule | Background | Outreach | Materials | Cost | Contact Us

Translated project materials available below

  • 中文 /Chinese
  • Español /Spanish
  • Tiếng Việt /Vietnamese
  • 한국의 / Korean
  • አማርኛ / Amharic
  • ትግርኛ /Tigrinya
  • Oromiffa/Oromo
  • Somali/Somali


Project updates – May 21, 2015

Construction forecast at-a-glance

On June 8, crews working for the Seattle Department of Transportation (SDOT) will begin major construction on 23rd Avenue between E John and S Jackson streets. Phase 1 construction will start in Zone A, which is between S Jackson and E Cherry streets. To learn more, read the construction fact sheet or visit the virtual construction open house we launched in March.

Before major construction begins on 23rd Avenue, SDOT will be working to wrap up work on Phase 1 of the adjacent Central Area Neighborhood Greenway. We began installing the greenway in late February and we expect to complete work by the end of June. The greenway will create a quieter, safer route for people to bike and walk. For more info about the route or list of improvements, read this handout about Phase 1 of the greenway project.

SPU early utility work complete

Crews from Seattle Public Utilities (SPU) wrapped up utility preparation work on 23rd Avenue, replacing some older water service lines in preparation for replacing the 100-year-old water main underneath the road. This work began on April 6 and was completed on April 30. Thank you for your patience and cooperation during this work.

Next monthly community drop-in scheduled for June 15

Each month throughout construction, SDOT will host a drop-in session to answer questions and share the latest construction information with community members and commuters. Join us for a drop-in on June 15! 

Monday, June 15, 2015, 5:30-7:30 PM
Garfield Community Center
2323 E Cherry Street, Seattle, WA 98122

Questions during construction?


What to expect – northbound closures and detours during construction

Construction between S Jackson Street and E John Street is expected to last approximately 20 months. To ensure the safety of pedestrians and drivers, as well as to allow enough space for crews to safely complete their work in a timely manner, northbound traffic in the active work zone will be detoured to Martin Luther King Jr Way. Southbound traffic will be maintained, though reduced to one lane at most times.

23rd Avenue is a narrow street. Maintaining two-way traffic request 22 feet, or 11-foot-wide lanes, at a minimum. Construction activities and equipment require approximately 30 feet of the roadway. The graphic below illustrates why there is not enough space in the road to accommodate more than one lane of traffic during construction.

Click to view larger

To minimize the impact of construction in front of your home, business or route to school or work, Phase 1 construction will be divided into three zones.

  • Zone A: S Jackson Street to E Cherry Street – Approximately 8 months
  • Zone B: E Cherry Street to E Union Street – Approximately 6 months
  • Zone C: E Union Street to E John Street – Approximately 6 months

click to view largerWhile construction is happening in your zone, you should expect the following:

  • Traffic closures and changes:

    • Full northbound closure of 23rd Avenue with a detour to Martin Luther King Jr Way
    • Southbound 23rd Avenue traffic reduced to one lane
    • Longer travel times in the area
    • Metro bus reroutes and stop relocations
    • Restricted access to residential side streets from 23rd Avenue

    Typical work schedule:

    • Monday through Friday between 7 AM and 5 PM
    • Periodic evening and weekend work

    Other temporary construction impacts:

    • Noise, dust and vibration
    • Heavy equipment and trucks traveling and staging
    • Pedestrian detours
    • Short-term driveway impacts
    • Short-term water service interruptions
    • Temporary loss of parking on side streets

How to use the detour

Northbound traffic within the active construction zone will be detoured east to Martin Luther King Jr. Way. To access a home or business mid-zone, drivers will need to use Martin Luther King Jr. Way (or another nearby arterial) to travel northbound and turn onto an east-west street at the end of a zone – S Jackson, E Cherry, E Union or E Madison/John streets – to then go southbound on 23rd Avenue. Use the detour map at right to determine how to access a business or residence mid-zone on 23rd Avenue.

We expect the first few weeks of detours to be a challenge as you adapt to the new routes. We appreciate your patience as we make adjustments to keep traffic and people moving – please plan for extra time as you travel through the corridor.

How to access your home or business during construction

Pedestrian access to your home or business entrance will be maintained. Crews can close driveways temporarily for up to 48 hours at a time, but the Community Liaison will notify businesses and residents prior to driveway work. For businesses with a driveway of 20 feet or wider, crews may be able to work on half of the driveway at a time to maintain access.

Plan ahead for driveway and side-street closures by identifying alternate routes and parking or loading areas on nearby streets.

King County Metro bus detours and stop changes

Generally, detours will only be in place when necessary, as affected by construction. For example, northbound Route 48 will use Martin Luther King Jr Way when work is happening in a zone, and then cut back over to 23rd Avenue to continue north. Southbound bus service on 23rd Avenue will be maintained, but likely experience some delays. See the bus detour map and descriptions by route below for more information.

Southbound Route 48: Southbound service may be delayed, but will continue on 23rd Avenue. Some bus stops may be temporarily closed, as needed for construction. Adjacent stops will remain open.

Northbound Route 48: During active construction in a zone, northbound Route 48 will follow the Martin Luther King Jr Way detour, along with general purpose traffic, and go west back to 23rd Avenue at the end of the active work zone to continue north on 23rd Avenue. See map.

Two additional temporary stops will serve northbound Route 48: just north of S Jackson Street and just north of E Yesler Way on Martin Luther King Jr Way.

Southbound Route 4: On weekdays, Route 4 will only operate as far as 21st Avenue and E James Street. Route 4 will not travel south of Garfield High School on weekdays because this route uses trolley buses and no substitute diesel buses are available on weekdays.

On weekends, Metro will operate a revised Route 4 using a diesel bus that does not require trolley wire. See map

Northbound and southbound Route 8: Will operate on Martin Luther King Jr Way between S Jackson Street and E Yesler Way. See map. (They will not operate via S Jackson Street, 23rd Avenue S and E Yesler Way northbound or via E Yesler Way, 23rd Avenue S and S Jackson Street southbound.)

Two additional temporary stops will serve northbound Route 8: just north of S Jackson Street and just north of E Yesler Way on Martin Luther King Jr Way.

Likewise, one additional temporary stop will serve southbound Route 8: just south of E Yesler Way on Martin Luther King Jr Way

Visit Metro’s Rider Alerts page to get the latest information about your route and any changes during construction. In advance of bus route changes, Metro will:

  • Update the Trip Planner
  • Update data for OneBusAway website and smartphone app
  • Post Rider Alerts at affected stops
  • Post routes changes on the Rider Alerts page
  • Notify Rider Alert subscribers of the changes via text message

Keeping your neighborhood safe and moving during construction

To balance the various needs of everyone who lives, works, plays and goes to school on and around 23rd Avenue, we have identified some tools to help manage traffic and keep people safe on the neighborhood’s streets. These include:


  • Signal timing modifications to keep traffic moving
  • Left-turn restrictions to minimize traffic backups and improve traffic flow
  • Signage, including detour information
  • An adjacent neighborhood greenway to provide a safe place for people to walk and bike


  • Uniformed police officers (UPOs) and flaggers on site
  • Traffic speed and volume analysis
  • “Local Access Only” signs and speed trailers where warranted, based on analysis

How will the contractor rebuild the street?

The construction work to rebuild 23rd Avenue will consist of four main activity types:

  • Removals
    • Remove select street trees
    • Remove the existing roadway
  • Utility work
    • Replace the water main
    • Install drainage pipes
  • Rebuilding
    • Repave the roadway
    • Install sidewalks and new curb ramps
  • Final restoration work and clean up
    • Plant street trees
    • Restripe and cleanup

Click here for more detail on these construction activities.

Neighborhood Greenway

Phase 1 installation of the Central Area Neighborhood Greenway has begun. The greenway will provide a space for people to bike and walk next to 23rd Avenue, but generally away from active construction.

Your favorite businesses and organizations will be open during construction

In addition to safety and mobility, we want to ensure the local businesses and places you visit regularly remain accessible during construction.

To help local businesses stay accessible and minimize some of the construction impacts they may experience, the City will:

Minimize impact to customer access

  • Divide the construction work into three zones to limit the amount of construction time in front of any one business
  • Ensure the contractor provides continual pedestrian and vehicle access for customers
  • Place “Businesses Are Open” signs to encourage patronage during construction
  • Limit the number and duration of interruptions to driveway access
  • Keep the project area as tidy as possible throughout construction

Provide communication tools to businesses

  • Provide businesses with project information cards for front counters and/or customized maps or materials to support their individual marketing efforts
  • Have a community liaison available on-site or by phone 24 hours a day
  • Provide advance notice about construction activities, including email updates and door-to-door flyers
  • Host monthly drop-in sessions to discuss construction updates and any community concerns
  • Maintain a website with updated construction information

The City has additional resources available for businesses and organizations affected by construction; see our project materials section below. If you are a local business/organization and would like more information, please contact the Office of Economic Development directly at 206-684-8090.

Construction contact information

Construction can be difficult. If you experience any issues or have questions during construction, please contact the community liaison via phone or email anytime, day or night:



The 23rd Avenue Corridor Improvement project includes three phases:

Phase 1: S Jackson Street to E John Street – construction starts in 2015 

  • Zone A (S Jackson Street to E Cherry Street): approximately 8 months
  • Zone B (E Cherry Street to E Union Street): approximately 6 months
  • Zone C (E Union Street to E John Street): approximately 6 months

Phase 2: S Jackson Street to Rainier Avenue S- construction starts in 2017 (pending additional funding)

Phase 3: E Roanoke Street to E John Street – transit stop improvements only – construction starts in 2017 (pending additional funding)

Click to view larger


For a good introduction to the project, be sure to check out our online open house or watch our overview video.

The Corridor

23rd Avenue is an essential arterial that connects a variety of users to businesses, educational institutions and residences in the Central District and beyond. Approximately 13,400-20,000 vehicles use 23rd Avenue each day. This area also serves high volumes of pedestrians, bike riders, and transit users (approximately 6,000 daily transit riders).

Why is the project needed?  
The corridor is in poor condition. Currently on 23rd Avenue, there are:

  • Many collisions (more than 900 reported in five years)
  • Poor road conditions (e.g. potholes, cracked pavement)
  • Narrow lanes
  • Back-ups created by left-turning vehicles
  • Narrow and uneven sidewalks
  • Inadequate buffers between vehicles and pedestrians

Improving safety and mobility in your neighborhood

In June 2015, the Seattle Department of Transportation (SDOT) will begin construction on 23rd Avenue between S Jackson Street and E John Street. This is the first phase of a project to improve safety and mobility for people who drive, walk, bike and take transit in the area.

Project improvements vary by phase and include:

  • Modifying 23rd Avenue from a four-lane street to a three-lane street - one lane in each direction with a center left-turn lane (key intersections will stay four lanes)
  • New pavement
  • Widening sidewalks to at least five feet and repairing broken and buckling sidewalks
  • Installing new streetlights
  • Upgrading traffic signals to give transit priority at key locations
  • Consolidating bus stops to improve transit speed
  • Replacing a 100 year-old water main that runs underneath 23rd Avenue
  • Installing public art near 23rd Avenue and E Union Street
  • Implementing a greenway adjacent to 23rd Avenue, to create a quieter, safer route for people to bike and walk

The new roadway – opportunity for a safer 23rd Avenue

The new corridor will have wider lanes – one in each direction – plus a 10-foot-wide center turn lane. The turn lane will allow left-turning vehicles to make a safe left turn, while still allowing thru-traffic to continue through an intersection and down the street.

On streets with 25,000 vehicles per day or fewer, such as 23rd Avenue, changing the street design from four lanes to three  can increase safety by reducing collisions, reducing speeding, allowing vehicles to turn without blocking traffic, managing drivers cutting in and out of lanes, creating space for wider sidewalks, making streets easier to cross and making it easier for freight and transit to travel. At most bus stops, the road will flare to approximately 18 feet, where buses can pull to the side and vehicles can pass the stopped bus in the travel lane. The City is also working with King County Metro to determine the benefits of electrifying the Route 48 line. The results from the study can be found in the Project Materials section below.


cross section

Public Outreach

SDOT is committed to engaging with the community and understanding the needs in the project area. To get ready for construction, we are conducting door-to-door outreach, briefing community groups and businesses, sending email and online notifications, and hosting a pre-construction open house. Please contact us if you would like to request a community briefing. 

To receive project email updates, sign up below!

Email address:

Project Materials

Current materials

Translated materials

  • Phase 1 Construction Handout


Previous materials


Project Cost

The project is being funded by a number of sources – local, state and federal. To date, the City of Seattle has allocated $45 million for improvements to the corridor. Phase 1 is fully funded. Phases 2 and 3 design are fully funded. Additional funding is needed for Phase 2 and 3 construction.

Questions or Comments?

Call the 24-hour project construction hotline: 206-727-8857

Maribel Cruz
Project Communications Lead

Therese Casper
Project Manager

To request information in another format:

If you need this information translated, please call (206) 727-8857.

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