Weekly Update: West Seattle Bridge

West Seattle Bridge at sunset. Photo Credit: Madison Linkenmeyer

Every Monday, we post a blog to keep you informed about our progress to stabilize the bridge, our efforts to address traffic and mobility, and other items related to the West Seattle High-Rise Bridge closure. 


In this week’s update:


West Seattle High-Rise Bridge Stabilization

We’re close to concluding the emergency measures that we’ve been constructing since May to stabilize the bridge and prevent further cracking. This was necessary whether we chose to repair or replace the bridge. In the past two weeks, we installed the new lateral bearings at Pier 18 and continued to install carbon fiber wrapping.

Pier 18 Bearing Replacement

Concrete blocks that will function as joints to hold the new lateral bearings in place.
We poured and cured concrete blocks that will function as joints to hold the new lateral bearings in place.

Last month, we released the damaged bearings at Pier 18, located on the east side of the Duwamish Waterway. Pier 18’s neoprene lateral bearings were compressed and bulging, locking together two critical parts of the bridge that typically are independent of each other. This was creating additional pressure and preventing the bridge from moving as it should. Last week, we finished pouring and curing the concrete that will hold the new lateral bearings in place. We then released and removed temporary restraints to begin clearing the work site.

Carbon Fiber Wrapping

We’re making progress on the last round of carbon fiber wrapping, which we’re on track to complete in mid-December. Carbon fiber wrapping helps support the now-stable and strengthened bridge. This is the last step in the stabilization project. Following the conclusion of the stabilization project, we’ll begin work on design and planning for the next phase of repair.

Upcoming Work

We’re on track to complete the stabilization work by the end of this year. As soon as the end of December, all work platforms will be lowered onto barges and temporary work structures will be removed. We’ll continue 24/7 monitoring and regular visual inspections after stabilization work is complete.

Stabilization sets the stage for upcoming repairs of the West Seattle High-Rise Bridge. Stabilizing the bridge after we closed it to traffic was crucial to preventing further crack growth and preserving the structure’s integrity. We’ve been implementing stabilization measures that will facilitate a smooth transition to repair.

Construction Impacts  

Kraemer North America, our contractor for the stabilization work, is working Monday through Saturday from 6 a.m. to 4:30 p.m. to stabilize the bridge. People driving may see lane reductions on Klickitat Ave SW and SW Klickitat Way (on the west and south sides of Harbor Island).

Past Work  

Stabilizing the West Seattle High-Rise Bridge is necessary to preserve public safety and the integrity of the bridge as we continue the full bridge repair work. Read our blog for information on the progress we’ve made since we closed the bridge in March.


Upcoming Live Load Testing on Terminal 5 Bridge

Starting on December 9, the Port of Seattle will conduct live load testing for the Terminal 5 (T5) bridge. Live load testing entails installing sensors on the bridge and running a truck (with a known weight and axle spacing) across the bridge. The information the Port receives from the sensors can be used to understand how the bridge responds to vehicle loads and ultimately to determine the bridge load rating.

Dec. 9 – 13: Upcoming Short-Term T5 Bridge Closure

Crews will close the T5 Bridge intermittently to vehicle traffic from Wednesday, December 9 through Sunday, December 13 between the hours of 7 a.m. to 4 p.m. The bridge will be completely open to traffic after work is done for the day at 4 p.m. 

Dec. 12 – 13: Upcoming Short-Term Lane Closure on West Marginal Way SW

This map shows the temporary, intermittent road closure on the Terminal 5 Bridge and a temporary lane reduction on West Marginal Way SW near the Terminal 5 Bridge. An orange line on Terminal 5 Bridge shows it will be closed December 9-13 from 7am to 4pm. A yellow line on West Marginal Way SW shows a lane reduction December 12-13 from 7am to 4pm.
This map shows the temporary, intermittent road closure on the Terminal 5 Bridge and a temporary lane reduction on West Marginal Way SW near the Terminal 5 Bridge.

On Saturday, December 12, and Sunday, December 13, one lane of West Marginal Way SW, just north of the Low Bridge (SW Spokane Street Bridge—see map), will be closed between 7 AM and 4 PM. The single-lane closure will allow the Port of Seattle to gain access to the underside of the segment of the bridge that crosses over W Marginal Way SW and to install sensors for the live load testing.

A Regular Bridge “Check-Up”

Generally, we conduct live load testing to evaluate how weight is distributed along a bridge when a vehicle is on it. A bridge load rating helps us establish an accurate weight capacity for the bridge by current standards, which is important to keeping users safe and maximizing the lifespan of the bridge. Updated bridge load ratings are required for all Federal Highway Administration bridges by the end of 2022 to account for changes in the sizes and weights of vehicles seen on roadways over the years. Live load testing is the most appropriate method of determining that rating for this bridge. With this information, the Port of Seattle can determine appropriate usage and any potential next steps for the bridge.

The Port of Seattle is conducting this work with support from SDOT crews. It’s a routine part of bridge maintenance and has no correlation to the West Seattle High-Rise Bridge closure or the operations of the Low Bridge (SW Spokane Street Bridge).

Questions About Our Work?

Email us at westseattlebridge@seattle.gov or call (206) 400-7511


Dec. 9 – 10: South Park Bridge (16th Ave S Bridge) Nighttime Closures

The South Park Bridge (16th Ave S Bridge) will be closed from 10:30 p.m. to 6 a.m. the nights of Wednesday, December 9 and Thursday, December 10 for inspections by King County Road Services. A signed detour will direct travelers to the 1st Ave South Bridge during that time. 


Week of Dec. 7: Low Bridge Camera Installation

Photo of the east entrance to the West Seattle Low Bridge. Trucks and cars are shown both driving away from the direction of the camera and coming towards the direction of the camera.
The east entrance to the Low Bridge. Photo Credit: Tim Durkan.

Starting in January 2021, we’ll be using a new automated photo enforcement system on the Low Bridge to limit unauthorized users between 5 a.m. and 9 p.m. each day. We already installed signs letting people know that photo enforcement will be used on the bridge, and now we’re ready to install the equipment.

We’re installing photo enforcement cameras near the Low Bridge this week (the week of December 7). If you are authorized to use the Low Bridge, then drive slowly and carefully in the construction zone. Flaggers may direct you through temporary lane shifts during installation. 


New Reconnect West Seattle Project Dashboard

Image of the Reconnect West Seattle project dashboard. The dashboard looks like a Google map with colored pins in specific locations on the map.
The Reconnect West Seattle project dashboard shows “pins” at each project location.

We recently launched a new project status dashboard to show the status and progress of the many Reconnect West Seattle projects designed to help mitigate the effects of the West Seattle High-Rise Bridge closure. The map uses the Google Maps interface, and has “pins” in three different colors to differentiate between projects:

  • Blue for projects which began/are beginning construction in 2020
  • Orange for projects beginning in 2021
  • Green for projects that do not yet have an estimated start date

The map will be updated on a regular basis, so keep it bookmarked for ongoing updates! 


Dec. 2 West Seattle Bridge Community Task Force Meeting

The West Seattle Bridge Community Task Force (CTF) met last week to discuss Mayor Durkan’s decision to repair the West Seattle High-Rise Bridge and the CTF’s role moving forward. CTF members shared what they’ve heard from their communities about the repair decision, and their priorities between now and when traffic returns to the West Seattle High-Rise Bridge in 2022.

The CTF will continue meeting regularly in 2021 to ensure that West Seattle and Duwamish Valley residents are informed and heard throughout the repair and Reconnect West Seattle process. You can watch a video of the full Dec. 2 meeting here.