SR 520 Bridge Replacement and HOV Program


The westbound lanes of SR 520 will close for construction work from 11 p.m. Friday, Feb. 26 to 5 a.m. Monday, March 1 between 92nd Avenue Northeast and Montlake Boulevard. This is the third of four SR 520 closures this winter so crews can set large concrete girders for a new freeway lid in Montlake and complete other tasks. For the most up-to-date information about SR 520 construction activities and planned road closures, check our SR 520 Construction Corner and its interactive construction map. You also can view Montlake Project construction photos taken daily, 'round the clock, by four mounted construction cameras.

Current News

Join us online March 4 to learn about two SR 520 & Alaskan Way Viaduct contracting opportunities

WSDOT is hosting a virtual meeting for contractors on Thursday, March 4 regarding contracting opportunities with two design-bid-build projects for the SR 520 and Alaskan Way Viaduct Replacement programs. Please register online via Zoom to receive a link to join the 2 p.m. meeting. This meeting is open to interested contractors of all sizes, from large primes to smaller minority-, veteran-, and women-owned businesses. The two upcoming projects are the SR 520/I-5 Express Lanes Connection Project and the AWV South Access Surface Street Connections Project. Construction for both projects is slated to begin in spring/summer 2021. The meeting will include a WSDOT presentation and time for Q&A.

Montlake lid begins to take shape

Aerial photo over State Route 520 in Seattle showing dozens of gray concrete beams aligned in a grid over the highway where a new freeway lid will be built.

Crews on the SR 520 Montlake Project set in place 84 concrete beams, or girders, over the highway (shown above) during two one-direction, weekend closures of SR 520 in late January and early February. Once 30 more girders are set in early March, crews will turn to building a three-acre freeway lid atop the beams. The lid -- between new crossings to be built at Montlake Boulevard (at left in the photo) and 24th Avenue East (at right) -- will feature landscaped open space, a regional transit hub, and improved connections to local and regional shared-use trails.

Read our recap of SR 520 Program highlights in 2020

2020 was a challenging year for everyone, but our SR 520 Program staff and contractor crews still managed to make great progress with the highway corridor’s reconstruction. Read our program administrators’ email update for a summary of our 2020 highlights, along with a peek at what’s in store for SR 520 work in 2021 and beyond. 

What a difference a year makes

side by side photos showing SR 520 construction progress from December 2019 to December 2020

These east-facing photos, taken one year apart, show the progress WSDOT contractor crews have made building temporary work platforms (at right) and removing the old SR 520 bridge over Union Bay. Crews on the SR 520 Montlake Project are cutting up large sections of the highway's old west approach bridge for removal by truck. They're also using the platforms to build a seismically resilient, three-lane bridge between Montlake and the SR 520 floating bridge. Once that new eastbound bridge opens, expected in 2023, the north span will revert back to a westbound-only bridge.

Program overview

The SR 520 Bridge Replacement and HOV Program is enhancing public safety and mobility by replacing the highway's aging, vulnerable bridges and making significant transit and roadway improvements throughout the corridor. Built in stages, the construction program's completed and planned improvements extend from I-405 in Bellevue to I-5 in Seattle.

map of the SR 520 corridor's major projects

Click on the map above to visit our SR 520 Major Projects webpage.


Phone: 206-770-3500
Find SR 520 Program contact information: Contact Us