I-90 - Snoqualmie Pass East - Keechelus Dam Vicinity to Stampede Pass Interchange (Phase 2) - Complete October 2019

Why did WSDOT improve safety and reliability on I-90?

Phase 2 was part of a 15-mile corridor improvement project to improve safety and reliability and reduce congestion along I-90 from Hyak to the Easton vicinity. On average, 31,000 vehicles travel over Snoqualmie Pass every day and traffic numbers double on weekends and holidays. Traffic volumes are expected to increase 1 percent every year, reaching an average of over 39,000 vehicles per day by 2040.

The End Result

WSDOT increased capacity and improved safety by:

  • Adding a new lane in each direction
  • Replacing concrete pavement
  • Stabilizing rock slopes
  • Building wildlife crossings
  • Straightening the roadway 
  • Adding new chain-up areas

Needs & Benefits

  • Safety. WSDOT improved the driving surface on I-90 by replacing the concrete pavement, straightening the roadway, and adding new chain-up areas.
  • Congestion Relief. WSDOT increased capacity by 50 percent in each direction to accommodate projected traffic volumes for the next 20 years by adding a lane in each direction.
  • Environmental. WSDOT minimized impacts to the environment and improved movement of wildlife.


  • Summer 2015 - construction began
  • Fall 2019 - construction completed


Funding Source ($ in Thousands)
$110,640 from 2005 gas tax (TPA)


Scott Golbek
Project Engineer
Phone: 509-577-1880

Summer Derrey
Phone: 509-577-1943

Thumbnail - I-90 - Phase 1 and 2 map

I-90 des vis thumbnail

Design Visualization of the I-90 Snoqualmie Pass East project.

Screenshot from Lifeline video

I-90 is a major transportation corridor in Washington state, find out why.

A design visualization of the wildlife overcrossing.

Take a look at all the progress crews are making on the project.