SR 520 Bridge Replacement and HOV Program - News and updates

Aug. 16, 2019 | Rest of the West news

Trolley line work on Montlake Boulevard scheduled for this weekend

King County Metro crews will adjust overhead trolley lines on Montlake Boulevard to prepare for upcoming Montlake Project construction. This work will take place from 7:30 a.m. to 6 p.m. daily, Saturday, Aug. 17, and Sunday, Aug. 18. Crews will intermittently close a single lane of either northbound or southbound Montlake Boulevard. Seattle Police Department officers will be on-site to manage traffic control.

Montlake nighttime work, off-ramp closure scheduled for next weekend

Westbound SR 520 off-ramp to Lake Washington Boulevard closes Friday night, Aug. 23  

If you’re traveling through the SR 520 corridor next weekend, be aware that the Lake Washington Boulevard off-ramp from westbound SR 520 will close for construction from 11 p.m. Friday, Aug. 23, to 5 a.m. Monday, Aug. 26. During the closure, bicycle and pedestrian access also will be closed across the 24th Avenue East overpass.

What to expect:

  • Drivers should detour through the Montlake Boulevard exit, and bicyclists and pedestrians should detour on Montlake Boulevard. Additionally, there will be short-term closures of the SR 520 Trail when equipment is moved across it. Flaggers will be present.

During this closure, crews will build a concrete block wall between the two off-ramps. This wall is part of a temporary Montlake Boulevard off-ramp that will be used during SR 520 Montlake Project construction. By scheduling this work over a weekend, crews are able to eliminate up to two weeks of weeknight ramp closures and nighttime work.

Investigation of contamination on gas station and market property continues with nighttime work Aug. 24-25

Following WSDOT’s acquisition of the Montlake Market and 76 gas station property in June, we are committed to cleaning up the contamination present on the site. In preparation for the cleanup work, WSDOT crews will conduct additional soil and groundwater investigations next weekend to evaluate the extent of the contamination.

Between 9 p.m. and 6 a.m. on Friday, Saturday and Sunday, Aug. 23-25, WSDOT contractor crews will conduct multiple borings into the ground on the market and gas station property and nearby areas. Investigation of material from the borings will help WSDOT develop a plan to efficiently sequence cleanup work and other Montlake Project construction needs.

Two construction workers guide a large drill into a roadway at night.

Crews bore holes for soil and groundwater testing.

What to expect

  • Crews will use drilling equipment to bore six holes on Montlake Boulevard and the eastbound SR 520 on- and off-ramp near the 76 gas station. Nearby neighbors may see lights and hear intermittent noise, including drill rigs and a vacuum truck, while the work is taking place.
  • This drilling activity will be done at night to reduce effects to nearby businesses and daytime traffic. Because the necessary equipment is louder than is typically allowed for nighttime work, the borings will be performed under a city of Seattle temporary noise variance. Residents of adjacent homes have been offered hotel stays, and a designated noise inspector will be on site to monitor and ensure that all available strategies are used to minimize effects to surrounding areas. Affected residents can call the Montlake Project 24-hour hotline (206-775-8885) to talk to project staff about questions or concerns.
  • Montlake business and traffic operations
    The market and gas station will remain open during their regular business hours and at least one gas pump will be open at all times. Some of the parking spaces may be used by drilling equipment. This work will require closing a lane on both Montlake Boulevard and the eastbound SR 520 on- and off-ramp. The closures will be coordinated to ensure Montlake Boulevard and the eastbound on- and off-ramp remain open at all times.

Updated Montlake Project Community Construction Management Plan now online

Thanks to all who provided feedback on the draft Montlake Project Community Construction Management Plan. The updated plan, including all of the appendices, is now available online on our Montlake Project webpage, under the “Project news” section. Based on public comment, you’ll notice a few changes in the updated version:

  • More information about how Graham, the project contractor, plans to use secondary haul routes for the project.
  • Clarification that haul trucks must cover their loads to reduce dust.
  • Information about traffic-calming measures implemented as part of the Montlake Project.

This document will continue to be updated throughout the course of the project.


Aug. 13, 2019 | Rest of the West news

Montlake Project update – nighttime noise variance goes into effect Friday, Aug. 16

Construction is underway on the SR 520 Montlake Project. Over the next four years, crews will build a seismically stronger, three-lane bridge over Union Bay for eastbound traffic, a highway lid in Montlake with a transit hub and landscaped open space, a new Montlake Boulevard interchange, and a bicycle and pedestrian bridge over SR 520.

As much as possible, Graham (the contractor) will work during the day to complete the project. As needed, Graham will work at night in order to minimize disruptions to daytime traffic and support the safety of the traveling public and our crews. Starting this Friday, Aug. 16, nighttime work will be done under a city of Seattle-approved Major Public Project Construction Noise Variance. This variance sets noise limits for nighttime construction activities and establishes a variety of operational requirements when crews are working between 10 p.m. and 7 a.m. on weekdays, and between 10 p.m. and 9 a.m. on weekends and legal holidays.

The noise variance requires crews to:

  • Use noise meters throughout the construction area to verify that nighttime activities remain within the decibel limits set by the city, and provide noise-monitoring reports to the city and the public to demonstrate compliance.
  • Deploy an independent noise inspector during all nighttime work to oversee noise monitoring and report on compliance directly to the city of Seattle. The inspector has authority to halt work if noise exceeds the limits set by the variance.
  • Prohibit noisy impact work at night, such as auger shaking, jack hammering and impact pile driving.

Additionally, WSDOT and Graham have voluntarily committed to the following measures:

  • Offer hotel accommodations to nearby neighbors when nighttime work is expected to be particularly noisy or extend for long periods.
  • Provide incentives for Graham to maintain positive community interactions, such as responsiveness to neighborhood concerns about noise, dust and lights.

You can read the noise variance application and decision on the city of Seattle’s website (document #3030792). You can also read more about our best practices to limit construction noise on our Construction Corner and in our Community Construction Management Plan (pdf 871 kb).

Aug. 7, 2019 | Rest of the West news

Montlake Project construction underway this week with nighttime off-ramp closures

If you travel through Montlake on SR 520, you may have noticed more construction activity this week on the SR 520 Montlake Project. Just like any good home improvement project, crews are starting with an important first step: preparing the work site.

What does this mean for you? If you have any nighttime journeys planned on SR 520, please be aware that the westbound SR 520 exit to Lake Washington Boulevard is closed nightly this week, through Saturday, Aug. 10, from 10 p.m. to 6 a.m.

In addition to the overnight ramp closures, this week you may see crews:

  • Installing fencing, erosion control, and water-treatment facilities at the Montlake work site
  • Removing trees and vegetation near SR 520 to allow construction of initial project elements
A map of the Montlake S r 520 interchange at the completion of Montlake Project construction. Labels on the map point out a new pedestrian land bridge, new eastbound lanes, a lid and transit hub, and an improved interchange.
Conceptual illustration of a completed Montlake lid and interchange, a pedestrian/bike land bridge, and a new, three-lane west approach bridge for eastbound SR 520 traffic.

Much of this work is to prepare for a major traffic shift (pdf 2.3 mb) later this fall, when crews will move eastbound traffic onto the West Approach Bridge North, which currently carries westbound-only traffic. This temporary shift will enable crews to replace the old, 1960s-era west approach bridge with a seismically stronger, three-lane bridge for eastbound-only SR 520 traffic.

We expect the Montlake Project to last approximately four years. Over the course of the project, short-term closures of on- and off-ramps at Montlake Boulevard, as well as lane closures on SR 520, will be required. Crews will often work at night and on weekends to avoid disruptions to daytime commuters and provide a safer work zone for both workers and the travelling public. Our nighttime work will comply with the noise limits and operational requirements spelled out in a Major Public Project Construction Noise Variance granted by the city of Seattle. 

Please visit and bookmark our SR 520 Construction Corner to find up-to-date information on SR 520 construction. The site includes an interactive construction map that shows the specific location and duration of near-term work, along with any associated road closures. The Construction Corner also describes our responsibilities and protocols for limiting the effects of our construction.

How to reach us and stay informed about SR 520 construction:

  • Call the 24-hour construction hotline (206-775-8885) with pressing Montlake Project questions or concerns.
  • Call the SR 520 Program information line (206-770-3554, M-F 8 a.m. - 5 p.m.) with general SR 520 inquiries.
  • Email SR 520 staff with your questions about the project or construction activities.
  • Visit the SR 520 Construction Corner for the most up-to-date information on closures and construction impacts.
  • Visit the SR 520 Program website to find general information about the project.
  • Follow us on Twitter @wsdot_520 to get key news and updates about the SR 520 program.

Get weekly updates via email

Visit the WSDOT email updates page, enter your email address, and under "Construction Reports" select one of the following:

"SR 520 Bridge Replacement and HOV Program"
The email update on the entire program, from I-5 to I-405. Includes information on highway closures, construction milestones, and upcoming public meetings.

"SR 520 Rest of the West News"
Construction is expected to begin in spring 2019 on our next stage of construction in Seattle -- the Montlake Phase. This update focuses squarely on SR 520 construction activities and impacts in Seattle.