South Spokane Street Viaduct Deck Rehabilitation

Updated September 17, 2024

What's Happening Now?

The South Spokane Street Viaduct Deck Rehab continues this week and weekend (September 18-23, 2024). However, the Spokane St Swing Bridge (also known as the West Seattle Low Bridge) is currently closed to motor vehicles as Seattle Department of Transportation (SDOT) crews continue to repair damage from a car crash on the evening of September 14. This ongoing closure could affect our schedule moving into the weekend.

If the Low Bridge is still not working by this weekend, our schedule between Friday and Saturday may need to chan. Please pay close attention to the schedule layout below, which is organized by the direction of lanes impacted, as opposed to dates.

If you have not already, you can sign up for email updates here.  

South Spokane Viaduct Location map

Project Background  

As its name suggests, the Spokane Street Viaduct (or the SSV) sits above South Spokane Street. The Viaduct was first built in the 1920s. Back then, it was one of only two road connections between West Seattle and downtown.  

The SSV is important to Seattle's transportation network. The Viaduct literally helps connect West Seattle to the rest of the city: people leaving Interstate 5 (I-5) use the SSV to enter the West Seattle Bridge and the Spokane Street Swing Bridge (aka the Low Bridge). Large, heavy vehicles travel across the bridge every day. Think heavy freight vehicles, buses, and hundreds and hundreds of cars. Add wet weather conditions to this equation and the wear and tear is inevitable.  

What are we doing? (Project Overview) 

To keep the SSV in good shape, we are dedicating the money, time, and labor to repair the road surface. We want to make sure the road surface (or what we call the deck) can handle that volume of cars, buses, and trucks. This Deck Rehabilitation project will replace the existing surface and fix these cracks using a stronger and more durable top layer of polyester coating. 

We will also update the scuppers. Scuppers let rain or other water drain into inlets. They are the are openings on the bottom of the bridge’s median barriers. We need those in good working condition so that water can drain from the road surface, making it safer to drive. 

Why are we doing this work (now)? 

The best answer to the above question is that a LOT of vehicles cross the Viaduct daily. While the SSV has undergone repairs and expansions in recent years, the deck occasionally gets cracks or other damage from the traffic. Again, a lot of people use the viaduct daily. If we do this work now, we can avoid the road surface deteriorating sooner. 

How will we do it? 

First, we grind down the current road surface. Then we blast that exposed road to give it a coarser texture. That coarseness will help the polyester coating stick better. Then we apply the polyester overlay! All three eastbound lanes will receive this treatment. We will also be doing spot repairs on the westbound lanes.   

We will also update the scuppers. Scuppers are openings on the bottom of the bridge’s median barriers. A scupper lets rain or other water drain into inlets. Water can then drain from the road surface, making it safer to drive. 

There will overnight closures most weeknights as well as entire weekends. We do this to protect the work zone. Depending on the location of our current work zone, you will need to consult the table(s) below to see detours. 

When we’re doing it (Schedule) 

Construction Updates:(*schedule is subject to change)   

Eastbound Work

Eastbound Right Lane Restrictions (Sept 19, 2024)

South Spokane Street Viaduct WB Lane Restrictions

Start Time End Time Lane Restrictions Ramp Closures

7 PM, Sept 19 (Thur Night)

6 AM, Sept 20 Eastbound Right Lanes

1st Ave S Off Ramp OPEN

4th Ave S Off Ramp OPEN

Eastbound Left Lane Restrictions (Sept 18 & 21, 2024)

SSV EB Left Lanes Closed

Start Time End Time Lane Restrictions Ramp Closures

7 PM, Sept 18 (Wed Night)

6 AM, Sept 19 Eastbound Left Lanes

1st Ave S Off Ramp OPEN

4th Ave S Off Ramp OPEN

4:30 PM, Sept 21 (Sat Aft)

6 PM, Sept 21

1st Ave Off Ramp OPEN

4th Ave Off Ramp CLOSED 

EB to NB SR-99 Ramp OPEN 

Eastbound Full Closures - Sept 21-23, 2024

SSV EB All Lanes Closed

Start Time End Time Lane Restrictions Ramp Closures

6 PM, Sept 21 (Sat Night)

5 AM, Sept 23 Eastbound Full Closure

1st Ave Off Ramp CLOSED

4th Ave Off Ramp CLOSED 

EB to NB SR-99 Ramp OPEN 

Westbound Work *Dependent upon weather and Spokane Street Swing Bridge/Low Bridge functioning

Westbound Full Closures - Sept 20-21, 2024

Start Time End Time Lane Restrictions Ramp Closures

10 PM, Sept 20 (Fri Night)

4 PM, Sept 21 Westbound Full Closure

WB S Spokane St Viaduct – from I-5 Interchange to SR 99 CLOSED

S Columbian Way Off Ramp to WB Spokane Viaduct – CLOSED. Ramp to Lower Spokane St will remain OPEN

NB I5 Off Ramp to WB Spokane Viaduct – CLOSED. Ramp to Lower Spokane St will remain OPEN

SB I5 Off Ramp to WB Spokane Viaduct – CLOSED. Ramp to S Columbian Way will remain OPEN

1st Ave S Off-Ramp CLOSED

1st Ave S On-Ramp CLOSED

Port of Seattle Terminals 5-18/Harbor Island/11th Ave SW Off-Ramp CLOSED 

EB S Spokane Street Viaduct All Lanes OPEN

Detours

Wednesday Night (Sept 18, 2024)

SSV EB Left Lanes w 1st & 4th

Tuesday & Thursday Night (Sept 17 & 19, 2024) 

SSV EB Right Lanes w 1st & 4th

Friday Night Through Saturday Afternoon (Sept 20-21 2024) *Dependent upon weather and Spokane Street Swing Bridge/Low Bridge functioning

SSV WB Closures

Saturday Afternoon (Sept 21, 2024)

SSV EB Left Lanes w/ no 4th

Saturday Afternoon through Monday Morning (Sept 21-23, 2024)

SSV All Lanes w/ 99

Funding  

The SSV is one of three Seattle bridges that will receive $4.5 million for repairs. The Federal Highway Administration Bridge Improvement Program supplies this money. Thanks to a Bipartisan Infrastructure Law, we can perform these repairs. 
 

Materials

  • We will share our outreach materials here when available
     

Transportation

Greg Spotts, Director
Address: 700 5th Ave, Suite 3800, Seattle, WA, 98104
Mailing Address: PO Box 34996, Seattle, WA, 98124-4996
Phone: (206) 684-7623
684-Road@seattle.gov

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The Seattle Department of Transportation (SDOT) is on a mission to deliver a transportation system that provides safe and affordable access to places and opportunities for everyone as we work to achieve our vision of Seattle as a thriving, equitable community powered by dependable transportation.