Traffic safety methods

Find details about the methods we use to keep travelers safe, including roundabouts, road equipment and striping, and workzone safety information.

Collector/distributor

Learn about collector/distributors and how they improve traffic flow on freeways.

Diverging diamond interchange

Learn about diverging diamond interchanges, a proven way to move more people and reduce the potential for collisions.

Roundabouts

Learn about roundabouts, including how to travel through them as a pedestrian, cyclist or driver.

Rumble Strips

Learn about how we use rumble strips to keep vehicles on the roadway and reduce the frequency of collisions.

Striping

Basic information about annual roadway re-striping work, and how you can help.

Work zone safety

Find important information about traveling in and around roadway work zones, including information on traffic control training and certifications.

Performance highlights from the Gray Notebook

8,683 animals crossed the Snoqualmie Pass East Project area

as recorded by WSDOT and partners in 2020 and 2021.

46% increase in Amtrak Cascades ridership to 251,000 passengers

in 2021 compared to 172,000 in 2020.

Nine wetland and stream mitigation sites across 32.7 acres added

to our monitoring program in 2021 to help offset climate change impacts.