Link to Transportation Home Page Link to Transportation Home Page Link to Transportation About Us Page Link to Transportation Contact Us Page
Delivering a first-rate transportation system for Seattle Scott Kubly, Director







Site Index

Neighborhood Traffic Operations Home
Frequently Asked Questions
20 MPH Zones
Traffic Circle Program
Typical Traffic Circle Design
Traffic Calming Program
Neighborhood Service Centers
Safe Routes to School Engineering Toolkit
Other Funding Sources

20 MPH Zones

Designing Safer Streets

August 18, 2015

Kids crossing a neighborhood street using a crosswalk

The goal of the 20 MPH Zone program is to improve safety and livability in Seattle neighborhoods by decreasing vehicle speeds. SDOT hopes that reducing neighborhood speed from 25 MPH to 20 MPH will make streets safer for all travelers.
There are two phases to our neighborhood 20 MPH Zone program:

  • Phase One: Install 20 MPH signs and 20 MPH markings on the street.
  • Phase Two: If speeds are not reduced with signs, install other safety improvements such as curb bulbs, speed humps, and other appropriate traffic calming devices.

Neighborhoods in cities all over the world are developing “Slow Zones”. That’s why we want to try out this program in Seattle.

  • London had a 46% collision reduction in their Slow Zones.
  • New York Slow Zones report slower and less aggressive driving.

SDOT will implement six pilot 20 MPH Zones in 2015. The locations were selected based on collision history, number of nearby pedestrian generators, geographical representation and partnership opportunities.

Seattle's 20 MPH Zones are part of a safety-based Vision Zero program that is a partnership between the Seattle Department of Transportation (SDOT) and the Seattle Police Department (SPD) to end fatalities and serious injuries on city streets by 2030.

Click on orange area to see a larger version of the 20 MPH Zone

Home | About Us | Contact Us | Site Index | News | FAQs | E-Mail Alerts