Preserving our roads & bridges

Learn how we maintain our state's highway system to keep people safe and goods moving 24-hours-a-day, 365-days-a-year.

We oversee the day-to-day needs of maintaining our state's highway system, including:

  • 20,679 highway lane miles (includes ramps, collectors and special use lanes).
  • More than 3,000 bridges.
  • 1,100 traffic signal systems.
  • 10 major mountain passes kept open all year.
  • Close to 50 safety rest areas.

Bridge & structure preservation

Learn how we preserve, inspect and rate the condition of Washington state bridges.

Chip seal

Learn about chip seals (or seal coating, BST, Bituminous Surface Treatment), the application of a special protective wearing surface to an existing pavement.

Performance highlights from the Gray Notebook

Traffic fatality crashes on Washington public roadways

increased 56% in March 2021 compared to March 2020.

11,906 incidents responded to

by WSDOT’s incident Response teams during the third quarter of 2021, nearly 6% more than same quarter in 2020.

WSF ridership was nearly 5.7 million in the first quarter of fiscal year 2022,

which was 1.6 million (38.3%) higher than the corresponding quarter in FY2021