Seattle Downtown Traffic Signal Re-Timing Project

Do you feel you need to wait too long or that you stop too often for traffic signals in downtown Seattle? If so, you might be interested in this on-going Seattle downtown traffic signal re-timing project.

Traffic Signal re-timing2

2nd Avenue

Seattle’s signal lights were timed around 10 years ago, but rapid growth, significant construction activity, fast growing employment, increased biking and walking activity, and special events have caused new bottlenecks that can result in abrupt traffic backups throughout the city.

Second Avenue at University Street

2nd Avenue at University Street

Seattle Department of Transportation is studying overall metropolitan traffic patterns to determine the most efficient way to optimize 300 signals in the Central Business District. Traffic signal retiming is one of the most cost-effective ways to reduce delays for people driving, biking, and taking transit, thereby making our downtown streets safer and more efficient. Comprehensive signal retiming programs have documented benefits of 7 to 13 percent reduction in overall travel time, 15 to 37 percent reduction in delay and 6 to 9 percent fuel savings (Institute of Transportation Engineers, 2009).

The purpose of this project is to develop and introduce enhanced signal timing models that respond to real-time traffic volume fluctuations, incidents, special events and traffic condition on freeways. A unique element of this project is the inclusion of a system that will change signal timing patterns in response to current travel time data. This will improve travel times, freeway access, transit speed and reliability.

Downtown Traffic Retiming Map

Downtown Traffic Retiming Map

SDOT plans to implement and fine-tune the new signal timings at the end of 2015 and expects drivers to see an improvement in travel times through downtown at the beginning of 2016.

SDOT Grants for Projects that Encourage Walking and Biking to School

Did you know SDOT’s Safe Routes to School program provides funding to any K-12 public school, private school, non-profit, or PTA for projects that encourage kids to walk or bike to school safely? The Mini Grant program has been supporting grass-roots efforts at increasing safe biking and walking since 2009.

Take, for example, Denny International Middle School’s Bike to School program. Last year the Denny PTSA hosted donut and fruit days for kids who biked to school, handed out lights, reflectors and gloves during the winter months to keep kids safe on their bikes, kept kids hydrated with water bottles during warmer months, and made sure kids knew how to bike safely all year round by broadcasting safety information.

Last May the PTSA hosted their annual Denny-Lincoln Classic family bike ride and doubled their attendance! They handed out snacks and student-designed t-shirts to all participants and made sure to give each bike a thorough check through the A (air), B (brakes), Cs (chains). The student bike riders wound their way through the neighborhood down to Lincoln Park and were joined by the West Seattle Bike Connections group, Denny M.S. staff, and Principal Jeff Clark. The ride ended with a barbeque and prizes at the park. What a fun day!

Safe routes

Denny International Middle School students/staff joined by West Seattle Bike Connections group.

If you have a great idea you’d like to make a reality at your school, we can help you make it happen. There are two chances every year to apply for funding: April and October. The application is simple, just tell us what you plan to do and how that will improve safety at your school and encourage more kids to bike and walk. Send in a letter of support from the school principal and your application is complete!

For more information visit: For questions, contact or 206-684-7577.

Vision Zero Pedestrian Safety Patrols Have Begun

The City of Seattle’s Vision Zero efforts are underway.  The Seattle Police Department has begun pedestrian safety patrols on Lake City Way NE as part of the Lake City Way Traffic Safety Project and Vision Zero. Safety Patrols will occur in the heart of Lake City between roughly NE 120th Street and NE 130th Street. 

Lake City Way NE near NE 127th

Lake City Way NE near NE 127th

Officers will focus on the mid-block crossings just north and south of the intersection of Lake City Way and NE 125th Street. The location was selected based on the number of total collisions that occur in this area which is busy with pedestrian, transit, bicycle and vehicular traffic. SDOT recently enhanced these crossings with rapid flashing beacons through the Lake City Way Traffic Safety Project. These beacons provide an increased awareness to drivers that pedestrians are in the crosswalk and that drivers should stop.  

Lake City Way SDOT Cam facing southbound

Lake City Way SDOT Cam facing southbound

Enforcement will also focus on behaviors that are most commonly associated with pedestrian collisions and target people that fail to yield to pedestrians. Officers will be on the look out for other behaviors that commonly lead to trouble on Lake City Way including speeding and distraction.

This effort is part of our ongoing work to enhance safety on Lake City Way. Travelers can expect to see increased law enforcement on Lake City Way today and throughout 2015. We’ve partnered with the Washington State Patrol to help monitor conditions on this busy northeast Seattle corridor. SPD will continue these patrols citywide through our Vision Zero enforcement efforts.

Remember always stop for pedestrians in the crosswalk. It’s the law and it’s the Lake City Way. 

Thank you for supporting safety.

Vizion Zero

LCW1 (2)


We look forward to “Future of Transportation in Cities” featuring Gabe Klein tonight and hope you’re joining

We look forward to hearing from Gabe Klein tonight at the first of the Transportation Speaker series. Cathy Duchamp from KUOW will be moderating at the Seattle Central Library from 6 p.m. to 8 p.m.  See you all there.

Gabe Klein

Gabe Klein

Speaker Series Banner




What is the future of transportation in Seattle? What can Seattle learn from other cities?

We’re bringing the expertise of four national and international leaders who transformed cities through transportation to help Seattle see our streets and sidewalks in a new light. Join these leaders of New York City, Washington DC, Chicago and Bogotá as they challenge us to develop a transportation system than can meet current demands while also looking ahead to future needs.

In four nights from March to June, come hear about the effects of new technology, demographic changes, quick project delivery, and emerging public space needs on transportation, as well as the impact transportation can have on Seattleites’ health, prosperity and happiness. Together, let’s find the answer to “Where are we Going?”

Wednesday, March 25 6 p.m. to 8 p.m. “Future of Transportation in Cities”

  • Gabe Klein – Urban Land Institute, fmr. Transportation Commissioner, Washington DC and Chicago
  • Moderator: Cathy Duchamp, KUOW
  • Seattle Central Library 1000 Fourth Avenue

Sponsors: Seattle Department of Transportation, Office of Arts & Culture, KUOW

For more information:

Managing Traffic with updated Traffic Signals and Information Systems on Mercer Corridor

The Mercer Corridor Project is transforming Mercer Street into a principal arterial street that better serves the growing South Lake Union and Uptown urban centers while continuing to provide access to and from I-5 and the future SR 99 Tunnel for these neighborhoods and others to the north and west.  Given the volumes of traffic exiting and entering I-5 at Mercer Street and dispersing from Mercer to north and south streets, as well as west toward Queen Anne, Magnolia and Interbay, SDOT is installing new traffic signals and communications systems to move people and goods more efficiently along and across the corridor as efficiently as possible.  Enhancements to maximize the benefit of the new signals and communications are coming soon.

New Signal Light at Mercer Street and 5th Ave North

New Signal Light at Mercer Street and 5th Ave North

The Mercer Corridor project installed or updated 30 signals on Mercer, Valley, Roy, and Republican streets and on Fifth Ave N.  All of the signals are connected to SDOT’s Traffic Management Center to allow for better communication and coordination between signals.  Each signal includes a controller that can be equipped with new traffic control technology – adaptive signal control – which will be coming to the Mercer Corridor in the near future.  Adaptive signal control allows the signal system to be more responsive to real-time traffic conditions.  Detectors in the street will monitor traffic volumes and feed that information to signals downstream from the traffic flow, so they can adjust timing to better accommodate traffic flows.

New Signal Controller at Mercer Street and 5th Ave North

New Signal Controller at Mercer Street and 5th Ave North

Adaptive signal control is expected to be most effective during the periods before or after the peak demand periods in the corridor, sometimes referred to as “the shoulders.”  It will be less effective during the peak periods, especially the evening peak, when traffic is backed up trying to get onto I-5 and other destinations. Even the latest technology cannot move more traffic when there’s no space ahead.  Adaptive signal control is also expected to improve operations for people leaving Seattle Center after an evening performance or other event.  In that case, the signals would detect the surge of eastbound traffic, along with the lower demands on side streets late at night and give more green time to traffic on Mercer Street.


The Mercer Corridor will be the first application of adaptive signal control in the city.  The City Council provided $1 Million in SDOT’s budget to design and implement the system on Mercer.  Specification and design is starting in 2015, and the system will be implemented on Mercer in 2016.  The next phase of adaptive signal control, after Mercer, will be on Denny Way.


Mercer Corridor Aerial 10-14

Mercer Corridor Aerial 10-14

SDOT is also implementing other features on Mercer Street that will provide more information to those traveling on Mercer and to the engineers programming the signals.  The department is measuring travel times on Mercer using Bluetooth technology.  This new system collects and summarizes travel time information at multiple locations along the corridor so the engineers can zero in on specific problem areas or intersections.  The travel time information will be added to SDOT’s Traveler Information Map and on the Traveler’s app.  This and other information will also be displayed on new variable message signs at Ninth Ave N and Sixth Ave N along the corridor, as well as a new variable message sign that will be installed on Elliott Avenue W.


For up-to-minute construction updates join our project email list at: or call the 24-hour construction hotline at 206-419-5818.

Improvements to NE 75th Street Successfully Reduce Collisions

Seattle Department of Transportation (SDOT) announced the results of a before and after study evaluating the effectiveness of safety improvements on Northeast 75th Street between 15th Avenue Northeast and 35th Avenue Northeast. The findings indicate the changes have dramatically improved safety, benefitting everyone who uses the street.

The main safety improvement on Northeast 75th Street, implemented in August 2013, was adding lane striping to define a previously unstriped area as having one lane in each direction with a center turn lane. Little-used on-street parking was removed to prevent general traffic from using that space as a second lane, helping to reduce speeding and to make it easier for pedestrians to cross the street. School zone photo enforcement cameras were also installed in September 2014 at Eckstein Middle School.

NE 75th Street Before Safety Improvements

NE 75th Street Before Safety Improvements

NE 75th After Safety Improvements

NE 75th After Safety Improvements


Collision statistics from September 2013 through August 2014 show a 45 percent reduction in collisions from the time before the improvements were made, and no collisions involving pedestrians. Also, the number of drivers exceeding the 30 mph speed limit by 10 mph or more has declined significantly – by 75 percent for eastbound traffic and nearly 80 percent for westbound traffic.

The safety improvements did not increase the time it takes to drive this segment of street, also reported in the study and contrary to common perceptions. Furthermore, the volume of traffic remained unchanged, indicating traffic is not spilling over onto nearby streets. In fact, traffic volumes have actually increased slightly on 75th since the completion of the project.

SDOT traffic planners will continue to monitor traffic on Northeast 75th Street and nearby streets, looking for opportunities for additional safety measures, including improvements on Northeast 75th Street where it turns into Banner Way Northeast, near I-5. Please visit for the full report.

SDOT is analyzing several other corridors this year to identify ways to improve safety. Each is considered separately to identify improvements tailored to their unique characteristics. Traffic planners are currently studying 35th Avenue Southwest, Southwest Roxbury Street, Lake City Way Northeast and Rainier Avenue South. To learn more about Vision Zero, please see the program webpage at:

What Moves You, Seattle? Share Your Input on a New Transportation Levy Proposal

Seattle is one of the fastest growing cities in the country, and our transportation system is critical to our quality of life and economic vitality. Earlier this month, Mayor Ed Murray introduced Move Seattle — his ten-year transportation vision that integrates our long-term plans for walking, biking, transit, and freight and sets forth a holistic approach to meeting Seattle’s needs today and tomorrow.

To help make that vision a reality, the city will need to identify a replacement for the current Bridging the Gap levy that expires at the end of 2015. Today, Mayor Murray and SDOT Director Scott Kubly announced a proposal for a new levy the Transportation Levy to Move Seattle.

SDOT Director Scott Kubly  discusses the Levy to Move Seattle.

Mayor Murray and SDOT Director Scott Kubly (at podium) announce the Levy to Move Seattle.

The proposed nine-year, $900 million levy aims to take care of the basics by maintaining our streets, bridges, and sidewalks, while also investing in the future with improvements that give us more travel choices to move more people and goods in and around Seattle.


We’d like to get your input and reaction to this draft proposal before Mayor Murray sends it to the Seattle City Council in May. The City will need to submit a final levy proposal to King County by early August for it to be on the ballot in November 2015.

Your participation matters. Help shape our transportation future:

Visit to:


Attend an upcoming community conversation to talk directly with staff about the proposal and your transportation priorities:

Saturday, March 28:

  • New Holly Gathering Hall (7054 32nd Ave S, Seattle 98118): 10 AM –12 PM


Monday, March 30:

  • Roosevelt High School (1410 NE 66th St, Seattle 98115): 6 – 8 PM


Tuesday, March 31:

  • West Seattle High School (3000 California Ave SW, Seattle 98116): 6 – 8 PM


Learn more at



Parklet and Streatery Application Deadline Extended to March 30!

Interested in building a parklet or streatery but still need more time to complete your application? You’re in luck! We’re extending the application deadline for application to March 30 to give you more time to generate ideas and get the support of your neighbors.

Parklets and streateries are a great way to provide new open space in your neighborhood and help create more active and vibrant streets.

Montana Bar Parklet, at Howell and Olive Way on Capitol Hill.

Montana Bar Parklet, at Howell and Olive Way on Capitol Hill.

Best of all, applying to the program is easy! All we need for your initial application is:

  • The application form
  • Three letters of support from your community (four for a streatery)
  • A simple site plan showing the ideas for your parklet or streatery
  • A few photos of the proposed location


Still unsure if a parklet or streatery is right for your business or organization? Check out the Parklet Handbook and Streatery Supplement which detail what’s involved with both types of projects. These two documents have all the information you’ll need to understand how parklets and streateries are designed, permitted, built, and maintained.

Please keep in mind that all application materials must be emailed to by 5:00 p.m. on March 30, 2015. We’re excited to see your fun and creative ideas!

Spring Break Resurfacing in U-District

They plan to work on Brooklyn from Northeast 47th to Northeast 45th streets on Monday and Tuesday, March 23 and 24, from 7 a.m. to 7 p.m. if the weather is favorable. The street will be closed intermittently; alternate routes are recommended.

The crews then plan to move to Northeast 41st Street, working from Brooklyn to 11th Avenue Northeast from March 25 to 27 during the same hours, and this work is also dependent on favorable weather. NE 41st will be closed to through traffic.

University District Map

University District Map

Please be mindful that on-street parking will be restricted, so any cars left on that block may be towed.  All crosswalks and sidewalks will remain open during work hours.

Real Time Transit signs coming to Ballard, Wallingford and U-District

SDOT in partnership with King County Metro is installing 11 new Real Time Information Signs (RTIS) at bus stops along the NW Market Street/45th Street corridor through Ballard, Wallingford and the University District. These pole-mounted LED signs will let bus commuters know if their bus is on time or running late.  These new tracking tools will add to SDOT’s similar signs that were installed on the Jackson/Rainier corridor back in 2013.

RTIS Map Final

SDOT’s RTIS signs use up-to-the-minute data to deliver predicted bus arrival/departure times for routes using the stop where the sign is located. Knowing when your next bus is scheduled to arrive may seem like a simple piece of information, but these signs provide a number of other benefits to passengers, such as an increased sense of security that comes with knowing how long you’ll have to wait and whether you have time to run a quick errand or grab a snack. Additionally, real time transit signs have proven to be a cost-effective strategy for increasing transit ridership and transit users’ satisfaction with service, which reflects SDOT’s long-running efforts to improve transit reliability and rider experience.


Design visualization of a RTIS. The LED signs will let bus commuters know if their bus is on time or running late.

Design concept of RTIS

RTIS installation will require rebuilding the bus stops where the new signs will be located. Construction activities such as: saw cutting, sidewalk removal, underground electrical work, sidewalk replacement and RTIS installations are expected to begin this week and will continue for about three months, through early to mid-summer. As part of this work, crews will also complete a number of other pedestrian improvements, including new curb ramps and accessible pedestrian push buttons.





SDOT appreciates your patience during RTIS installation and hopes to minimize inconvenience; neighbors and travelers should expect:

  • Audible work activities including construction equipment noise and concrete replacement
  • Intermittent lane closures
  • Temporary sidewalk closures and detours
  • Temporary bus stop closures
  • Flaggers and uniformed police officers assisting with traffic control
  • Access to businesses and residences maintained


If you have questions about installation of the RTIS along the Market/45th corridor, please contact Paul Elliott at or 206-684-5321.


For more information on SDOT’s RTIS program:

Contact Jeff Bender at 206-684-8837 or