Noise and vibration monitoring in place; resources available for neighbors in construction areas
SEATTLE, WA – Skanska, a leading global construction and development firm, today announced that a major phase of construction activity for the new Portage Bay Bridge will begin next week, starting Monday, November 4. Crews will:
- Begin piledriving in Portage Bay
- Use barges for work trestle construction and hauling
- Continue using trucks for hauling on East Lake Washington Blvd
- Remove trees and vegetation around Boyer Ave E
- Continue lane closures around E Roanoke St, Delmar Dr E and Boyer Ave E
“People are going to start to notice a lot of work happening on the Portage Bay Bridge project starting very soon. It’s exciting because it means we’re one step closer to completing one of the final bridges in a series that are providing seismically resilient connections between the communities east of Lake Washington and Seattle,” said Robin Clarke, project engineer and community liaison for Skanska USA Civil. “We are heavy into preliminary design development right now, but also moving into things that community members will be able to see on a daily basis like access road grading, utility relocates, site set-up, grading for walls, tree and vegetation clearing, and more, and we want people to know what’s going on.”
Piledriving work
Starting November 4, crews will begin installing piles and building the temporary work trestle. Over the course of the project, the team will install more than 700 piles to support the new bridge and trestle. Piledriving will occur six days a week through April. Loud noise and vibrations from impact work should be expected Mon-Fri, 7 a.m.-10 p.m., and Sat, 9 a.m.-10 p.m., with occasional Sunday work 9 a.m.-10 p.m. To learn more about piledriving and watch videos about the various techniques used, visit the Washington State Department of Transportation (WSDOT) Portage Bay Bridge project page for What to Expect During Construction.
Real-time noise and vibration monitoring
To ensure noise and vibrations are kept within acceptable limits, Skanska has installed more than a dozen vibration monitors around the project area from I-5 to Montlake Blvd E, and 10 noise monitors throughout the area, as well. Each set of monitors provides real-time data to both WSDOT and Skanska, allowing the company to adjust operations and stop work, if necessary, if vibrations or noise exceed thresholds or permitted limits. During daytime construction, noise should stay at an average of 85 decibels, slightly louder than a kitchen blender.
Nighttime noise mitigation and community outreach
While there will be nighttime construction work (weekdays, 10 p.m.-7 a.m., and weekends 10 p.m.-9 a.m.), it will not include piledriving. The Portage Bay outreach team will notify neighbors in advance of nighttime construction that requires a Temporary Noise Variance. Neighbors may contact the Portage Bay outreach team hotline 24/7 at 206-319-4520. Additionally, WSDOT has a pilot program available if you have concerns with noise. To see if you are eligible to participate, please send an email to .
Local street traffic changes
Crews will continue working on local streets for potholing, boring and utility work. Flaggers, detours, some parking restrictions and lane closures will take place around E Roanoke St, Delmar Dr E and Boyer Ave E. These changes will be announced via email updates and on the Construction Corner website at sr520construction.com.
Barge and truck hauling
Barges will be used weekdays, 7 a.m.-5 p.m. to transport materials to the project area to reduce truck traffic on local streets. Barges will haul large materials and heavy equipment to Portage Bay. One barge will make an average of two trips per day to Portage Bay from the staging side at Lakepointe in Kenmore. Additionally, crews will haul construction trailers and material to the project site along E Lake Washington Blvd.
Tree and vegetation removal and restoration
To access the area for utility work in early 2025, crews will remove trees and vegetation around Boyer Ave E and the existing Portage Bay Bridge. Any planned removals are pre-marked and have been permitted for removal under the Tree and Vegetation Management Plan and Section 106. As the project progresses, additional trees will be planted on the east and west sides of the project area, including the new Roanoke lid, 10th Ave E and Delmar Drive E. At the end of the project, there will be more trees in the project area than there are today.
About the Portage Bay Bridge project
The $1.4 billion design-build project includes the construction of two new parallel bridges that meet current seismic resiliency requirements as well as dedicated HOV and transit lanes, completing the SR 520 Program’s transit and HOV enhancements between Redmond and Seattle. The eastbound bridge span will extend the regional bicycle and pedestrian SR 520 Trail across Portage Bay, connecting to the city of Seattle’s non-motorized trail network. Construction of the landscaped lid over the highway will create nearly 3-acres of open space and reconnect communities that were severed by the original construction of SR 520. The project has an anticipated completion date in 2031.