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23rd Avenue Corridor Improvements Project

Updated January 22, 2015

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 – December 2014

Phase 1 construction will begin as soon as late March 2015! You are invited to learn more about construction details at the pre-construction open house (likely in late February or March). Please check back for more information in February, or sign up below to receive project updates by email!


Improving safety and mobility in your neighborhood

As soon as late March 2015, the Seattle Department of Transportation (SDOT) will begin constructing improvements along 23rd Avenue between S Jackson Street and E John Street. These improvements will improve safety and mobility for drivers, pedestrians and transit riders. The project includes:

  • 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)
  • Repaving 23rd Avenue
  • 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
  • Working with Seattle Public Utilities to replace 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

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. The graphic below illustrates why there is not enough space in the road to accommodate more than one lane of traffic during construction.

To minimize the impact of construction in front of your home, business or route to school or work, 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

While construction is happening in your zone, you should expect the following:

  • Full northbound closure of 23rd Avenue with detours (23rd Avenue will generally be reduced to one southbound lane while work is taking place in a zone)
  • Northbound traffic should use Martin Luther King Jr. Way to detour to the next zone
  • Multiple weekend closures at major intersections
  • Occasional night work
  • Short-term driveway closures and sidewalk detours
  • Temporary loss of parking on side streets
  • Heavy equipment and trucks traveling and staging
  • Noise, dust and vibration

How to use the detour

Northbound traffic 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.

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
  • 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

Neighborhood Greenway

Phase 1 of the Central Area Neighborhood Greenway will be installed prior to construction along 23rd Avenue. 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:

  • Ensure the contractor provides pedestrian and vehicle access for customers
  • Place “Businesses Are Open” signs to encourage patronage during construction
  • Provide businesses with project information cards for front counters and/or customized maps or materials to support their individual marketing efforts
  • Limit the number and duration of interruptions to driveway access
  • Keep the project area as tidy as possible throughout construction
  • Provide advance notice about construction activities, including email updates and door-to-door flyers
  • Have a community liaison available on-site or by phone 24 hours a day
  • Maintain a website with updated construction information

The City also has additional resources available for businesses and organizations affected by construction. 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:

Phone: 206.733.9960 

Staff are currently available during normal business hours; a 24-hour hotline will be accessible just prior to – and during – construction

Email address:


Phase 1 (S Jackson Street to E John Street)

  • Construction: mid-March 2015 – late 2016
    • Zone A (S Jackson Street to E Cherry Street): approximately 8 months, roughly mid-March 2015 – December 2015
    • Zone B (E Cherry Street to E Union Street): approximately 6 months, roughly December 2015 – May 2016
    • Zone C (E Union Street to E John Street): approximately 6 months, roughly May 2016 – November 2016

Phase 2 (S Jackson Street to Rainier Avenue S)

  • Design: Spring 2013 – 2015
  • Construction: Likely 2017, pending funding

Phase 3 (E Roanoke Street to E John Street)

  • Construction of transit stop improvements could start as soon as 2017, pending funding


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).

The corridor is in poor condition, with narrow lanes and no turn lanes, many pothole patches and restricted and uneven sidewalks. The City of Seattle is investing in the Central District by improving 23rd Avenue to make it safer for those who drive, take transit and walk.

The new roadway – opportunity for a safer 23rd Avenue

On streets with 25,000 vehicles per day or fewer, redesigning a street 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. There will be a pre-construction open house in February 2015 to share construction details with the community and answer questions. Please contact us if you would like to request a community briefing.
Previous outreach efforts have included:

  • December 1, 2014: Met with the Central Area Chamber of Commerce (CACC) to discuss the planned improvements for the community.
  • November 2014: Conducted door-to-door outreach to businesses on and adjacent to 23rd Avenue to provide design and construction updates and answer questions.
  • September 27, 2014: Participated in the City’s Central Area Block Party.
  • September 10, 2014: Hosted a public drop-in session to share design updates for Phase 1 construction.
  • September 6, 2014: Staffed a booth at the Madrona Farmers Market.
  • August 2014: Visited business and residences along Phase 1 of the 23rd Avenue corridor and distributed project information and answered questions about the project.
  • August 16, 2014: Participated in the Central Area Community Festival.
  • August 2, 2014: Participated in UmojaFest.
  • February 2014: Hosted an open house for community members about the 23rd Avenue corridor, the planned improvements to the corridor and latest project schedule, as well as the selected route for the Central Area Neighborhood Greenway.
  • January 2014: Hosted three public drop-in sessions throughout the corridor to share design and schedule updates and answer questions.
  • Late 2013/early 2014: Presented project information to community, business and educational organizations.
  • Coordinated with the 23rd Avenue Advisory Core Team (ACT), an advisory group that collaborates directly with the City of Seattle and the community to ensure that the shared vision and implementation actions pertaining to the 23rd Avenue Action Plan (Union-Cherry-Jackson) reflect the voices and balanced interests of the community.
  • August 2013: Participated in the Central District Street Fair.
  • June 2013: Hosted an open house and presented the preferred alternative – a 3-lane cross-section with a parallel greenway facility – which was selected through community input and a Complete Streets assessment. The concept reflected strong community interest in improving pedestrian crossings and bicycle facilities in the corridor.
  • March 2013: Hosted an open house and presented several options for roadway cross-section improvements.
  • Regularly present to City advisory boards (Pedestrian, Freight and Bicycle) and Council. 

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?


Maribel Cruz
Project Communications Lead

Ron Scharf
Project Manager

To request information in another format:

If you need this information translated, please call (206) 733-9990.

Si necesita traducir esta información al español, llame al (206) 733-9990.

如果您需要此信息翻譯成中文 請致電 (206) 733-9990.

Kung kailangan mo ang impormasyon na ito na nakasalin sa Tagalog mangyari lamang na
tumawag sa (206) 733-9990.

Nếu quý vị cần thông tin này chuyển ngữ sang tiếng Việt xin gọi (206) 733-9990.

የዚህን መረጃ ትርጉም ከፈለጉ፣ በዚህ ስልክ ቁጥር ይደውሉ፡ (206) 733-9990.

ናይዚ ሓበሬታ ትርጉም እንተደሊኹም፣ በዚ ቁጽሪ ስልኪ ይድውሉ፡ (206) 733-9990.

Odeeffannoon kun akka siif (206) 733-9990.

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