South Spokane Street Project

Revised March 16, 2010

Upcoming closures and detours

Latest SDOT Blog story

The next major milestone in the South Spokane Street Viaduct Project (the structure that links the West Seattle Bridge to I-5) is the permanent closure of the First Avenue South on-ramp to the westbound lanes of the viaduct, tentatively scheduled for May 17. The ramp closure is required to widen the Spokane Street Viaduct to the north by approximately 41 feet. A new west bound on- and off-ramp will be constructed on 1st Avenue with plans to open for use by the end of 2011.

In the year and a half during which there will be no access to the Spokane Street Viaduct from surface streets in SODO, vehicles will be detoured to the low level swing bridge to get to West Seattle. Alternative routes are noted in the detour map below.

SDOT will be monitoring traffic flows along the detour routes following the closure to determine whether changes in signal timing or other measures are needed to keep traffic moving.

The South Spokane Street project creates a new two-lane eastbound off-ramp leading to Fourth Avenue South; relocates the westbound on- and off- ramps to a new First Avenue South ramp; widens the upper roadway to the north by 41 feet - between Sixth Avenue South and East Marginal Way; and rebuilds the lower roadway in concrete, with new curbs, sidewalks and improved pedestrian and bicycle access. Work on this long-awaited project began in 2008 and is set to wrap up in 2012.

Key Schedule Dates:

*all dates subject to change

Click here to view a larger version of this Project Overview Map

Overview:

The Seattle Department of Transportation (SDOT) is significantly improving the South Spokane Street Viaduct, the 60-year-old elevated roadway that connects I-5 to the West Seattle Bridge. SDOT’s design goals are to:

• Provide new access to surface streets from the upper Spokane roadway
• Reduce delays on the lower Spokane roadway at railroad tracks
• Facilitate transit access between West Seattle and downtown
• Reduce conflicts between rail and vehicle traffic modes
• Enhance freight mobility
• Improve safety and traffic flow for all travel modes

SDOT conceptually designed the South Spokane Street Viaduct Widening Project in 1995 and has been implementing it in phases due to funding availability (see Project History page for more details):

• Seismic retrofit (1998-1999) - Addressing safety issues first, the Viaduct was seismically retrofitted to improve the Viaduct's ability to withstand an earthquake.
• Median barrier installation (1999) - Continuing to address safety issues, SDOT installed a median barrier down the center of the Viaduct as an immediate solution to the growing number of collisions between oncoming automobiles. The barrier divides the two directions of traffic and all but eliminates the possibility of head-on collisions.
• Lower roadway utility relocations (2003) - In 2003, SDOT relocated utilities at the street level to make room for the Viaduct widening itself. The project included drainage, water and sewer lines, Seattle City Light electrical utilities, and improvements to the City's traffic signal system.
• Upper roadway widening, lower roadway improvements and ramp construction (2009 - 2012)
• Working for SDOT, Mid Mountain Construction is currently building the new off-ramp from the eastbound Spokane Street Viaduct to 4th Avenue South and is improving the lower eastbound Spokane Street roadway.
• Working for SDOT, PCL Construction Services, Inc., begins widening the Viaduct in January 2010 and will also build a new on- and off- ramp from westbound Spokane Street Viaduct to 1st Avenue South and rebuild the westbound lower Spokane Street roadway.

Widening of Spokane Viaduct (Upper Roadway)
Changes	Benefits
The upper roadway between 6th Avenue South and East Marginal Way will be widened to the north by 41 feet. The existing upper roadway deck will be repaved and variable message signs will be installed. Seismic strengthening of the viaduct will be completed.	The widened structure will allow room for: Two thru lanes of traffic in each direction A new westbound acceleration/ deceleration lane A permanent median Wider lanes and shoulders An additional eastbound HOV/Transit lane between East Marginal Way and 4th Ave South
New Eastbound 4th Avenue Off-Ramp
Changes	Benefits
A new eastbound, two-lane off-ramp will be added to the Spokane Street upper roadway. The ramp will touch down at 4th Avenue South, where vehicles may head either northbound or southbound on 4th Avenue South.	The new ramp provides eastbound travelers on the West Seattle Bridge with direct access to downtown Seattle via 4th Avenue South. This new exit will allow traffic to exit the viaduct east of the rail tracks and thus avoid surface congestion due to rail-caused delays for vehicles. In addition, whenever the upper roadway becomes congested due to back-ups onto I-5, the new ramp will allow drivers to exit onto surface streets.
Before	After
New Westbound On- and Off-Ramp at 1st Avenue
Changes	Benefits
The existing ramp at 4th Avenue South for westbound traffic will be replaced by a new ramp at 1st Avenue South, built to current design standards. The existing westbound 1st Ave. on-ramp will be demolished, as crews widen the upper roadway 41 feet to the north.	Relocating the westbound ramps to 1st Avenue South will improve westbound traffic flow and safety. (The existing ramps at 4th Avenue South require an abrupt weave from the I-5 merge to exit off the viaduct, and a sharp right turn to enter traffic westbound. The new westbound merge lanes at 1st Avenue South will allow for smoother and much safer entry to and exit from the upper roadway.)
South Spokane Street Reconstruction (lower roadway)
Changes	Benefits
The lower roadway will be rebuilt with curbs and gutters, and a new 10-foot wide sidewalk with landscaping will be installed along the north side of the lower roadway	The lower roadway will be rebuilt with curbs and gutters, and a new 10-foot wide sidewalk with landscaping will be installed along the north side of the lower roadway.

How to Stay Informed:

You can choose to receive information in a variety of ways during this project:

Listserve notices: We will distribute email announcements for impending lane changes or closures, detours, schedules, etc. as well as periodic information about progress on the project. Use the form below to be added to that email list.

Progress Bulletins: We will periodically create and hand-deliver notices to surrounding properties, providing information about recent progress, upcoming activities, expected impacts and mitigation measures. These will also be available on this Web site and the information will be distributed via the City's listserve.

Area-wide flyers: We will occasionally print and mail newsletters to businesses and residences in a large area with general project information, schedule updates and contact information. These will also be made available to community groups, libraries and other distribution venues. If you have a suggestion for a valuable distribution point, please let us know.

Web site updates: Information on the project will be maintained here. Flyers and newsletters will also be available online.

Project Update Briefings: We will provide periodic in-person updates to identify project stakeholders, such as West Seattle and Georgetown neighborhood organizations, the Freight Mobility Advisory committee (FMAC), the Manufacturing and Industrial Council (MIC), SODO Association and others. Contact us to find out about joining a group for a presentation, or having a presentation for your organization.

Alternative modes of communication: We are looking at other means of providing information on the current status of the project and on upcoming activities, including text messages and low power AM radio broadcasts. We are also posting project update stories to our Blog. If you have other suggestions on outreach methods, please let us know . We are committed to working with local community and business organizations to provide communications that meet their constituents’ needs.

If you would like more information about the project, please call or email LeAnne Nelson, SDOT Community Relations, at 206-684-3897 or by email at LeAnne.Nelson@seattle.gov .

Find alternatives to sitting in traffic.
WayToGo SODO! is your source for tools and incentives to reduce your solo driving.