Neighborhood Traffic Operations: Arterial Traffic Calming Program

Traffic calming on arterial streets is challenging because of the multiple purposes served by arterial streets.  Arterial streets move people and goods efficiently within and through the City, provide routes for quick and efficient emergency response; and serve as your neighborhood street.

Arterial traffic calming is an approach for designing and operating streets to improve safety, and encourage the traveling public to drive more slowly.  Along with enforcement, physical devices and visual cues in or adjacent to the roadway can induce drivers to travel at slower speeds.

Arterial traffic calming includes such measures as speed limit signs, speed cushions, radar speed signs, and increased enforcement.

If there is a school located on the arterial street you are concerned about, please contact Brian.Dougherty@seattle.gov.  Particularly if there is school crosswalk, flashing beacons with a 20 mile an hour when children are present sign may be an option.

Step 1 - Community Request

An individual or group can request traffic calming for an arterial street by calling SDOT Neighborhood Traffic Operations at (206) 684-0353. If you are leaving a message please include your name, address, a phone number, e-mail address, and the intersection. You may also go the Resident Request Form, or email us at Neighborhood.Traffic@seattle.gov.

Step 2 – Preliminary Traffic Safety Analysis and Prioritization

In the fall, SDOT will review all requests for traffic calming on arterial streets.  Staff will review street characteristics including land use, collision data, and existing speed data.  If there is no recent speed data, a 7-day speed survey will be conducted.

Based on SDOT’s analysis, the streets will be ranked and SDOT staff will develop appropriate traffic calming measures.

Step 3 – Arterial Traffic Calming Implementation

You will receive a letter in November that details SDOT’s analysis, what SDOT has done in the past to encourage lower speeds on your street, and what we plan to do.

Potential low-cost educational measures include additional speed limit signs, additional enforcement by the Seattle Police Department (SPD), and deployment of SDOT’s radar speed trailer as an educational measure.

Potential higher-cost Physical Traffic Calming Devices include radar speed display signs and  speed cushions, but other devices are also considered based on the street’s design characteristics and available funding.

If your street does not rate high enough for Arterial Traffic Calming funds, but physical traffic calming devices are feasible, you will be directed to Other Funding Sources.