Major projects

Alaskan Way Viaduct Replacement Program

The Alaskan Way Viaduct Replacement Program consists of 30 projects led by the Washington State Department of Transportation, King County, the City of Seattle and the Port of Seattle. The Federal Highway Administration is a partner in this effort.

Ferry system electrification

Washington State Ferries (WSF) is embarking on an ambitious initiative to begin the transition to an emission-free fleet through a hybrid electric ferry system. WSF operates the largest ferry system in the United States. It is also the biggest contributor or greenhouse gas emissions of any state agency in Washington, burning 19 million gallons of diesel fuel to support 24 million passengers every year.

This shift to hybrid electric ferries is in response to governor and legislative direction as well as alignment with the agency’s own long-range planning initiatives. To transition to a hybrid electric fleet, WSF is working on the three key elements of the electrification system – building new vessels, converting vessels, and electrifying the terminals.

I-405/SR 167 Corridor Program

The I-405/SR 167 Corridor Program stems from the I-405 Master Plan and SR 167 Corridor Plan, foundational documents that guide project development, funding and delivery. The I-405 Master Plan alone includes over 150 projects designed to improve travel between Lynnwood and the Renton/Tukwila area. When combined with SR 167, this north-south corridor forms a 50+-mile transportation system providing travelers with a reliable trip in the express toll lanes, regular lanes and high-capacity transit (bus rapid transit).

I-5 - Mounts Road to Thorne Lane I/C - Corridor Improvements

In July 2015, the Washington State Legislature included $495 million to fund the I-5 Mounts Road to Thorne Lane Interchange - Corridor Improvements project, as part of the Connecting Washington transportation revenue package. The project is funded through a 10 year period, from 2015-2025.

I-5 - SR 16 Tacoma/Pierce County HOV Program

The Tacoma/Pierce County HOV Program is a series of projects, spanning over 20 years, that build high-occupancy-vehicle (HOV) lanes on I-5, SR 16 and SR 167 in Pierce County.

I-90 - Snoqualmie Pass East Project

The I-90 Snoqualmie Pass East Project improves 15 miles from Hyak to Easton. Phases 1 and 2 from Hyak to the Stampede Pass interchange is complete. Phase 3 begins fall 2021.

Industrial Way/Oregon Way (IWOW) Intersection Improvements Project

The Industrial Way/Oregon Way (IWOW) Intersection is a four-legged intersection with Industrial Way (SR 432) as the east and west legs, Oregon Way as the north leg and SR 433 as the south leg, which crosses the Columbia River into Oregon.

The IWOW project is being designed to reduce traffic backups, improve travel reliability, maintain, or improve emergency response and facilitate more efficient travel through the corridor to support economic opportunities across the region.

North Spokane Corridor

The North Spokane Corridor (NSC) is a 10.5-mile multi-modal corridor. When complete, the NSC will be a 60-mile per hour, north/south limited access facility that connects I-90 at the south (just west of the existing Thor/Freya interchange) and connects to US 2 (at Farwell Road) and US 395 (at Wandermere) on the north end. Various stages of construction remain to complete the project.

Puget Sound Gateway Program

The Puget Sound Gateway Program combines the SR 509 Completion Project in King County and the SR 167 Completion Project in Pierce County to complete critical missing links in Washington state's highway and freight network. These projects build important new connections to the state's ports, improve the movement of freight and reduce congestion on local roads and highways. Both projects have multimodal benefits and together create 6.5 miles of new bike/pedestrian paths and 3.5 miles of new sidewalks.

SR 160 - Fauntleroy Terminal - Trestle & Transfer Span Replacement

The SR 160 - Fauntleroy Terminal - Trestle & Transfer Span Replacement project will replace the aging Fauntleroy ferry terminal to maintain safe and reliable ferry service for people who travel between West Seattle, Vashon Island, the Kitsap Peninsula and beyond. The terminal faces several challenges. Built in the 1950s, parts of the terminal are aging, seismically vulnerable and overdue for replacement. Rising sea levels could damage the structure from debris during high tides in the future .

SR 520 Bridge Replacement and HOV Program

The SR 520 Bridge Replacement and HOV Program enhances travel safety and mobility with modern, structurally stronger bridges, as well as substantial transit and roadway improvements along this urban corridor. Built in stages, the improvements extend from I-405 in Bellevue to I-5 in Seattle.