Spokane Street Viaduct Ramp & Widening Project

Revised June 24, 2008

Click here to view a larger version of the Project Overview (PDF)

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

This widening of the South Spokane Street Viaduct is the fourth and final phase of a project that was conceptually designed in 1995 and implemented in phases due to funding availability. The Project History page in this website provides a brief review of the prior work (seismic retrofitting, median barrier installation and lower roadway utility relocations.

Before	After
Changes	Benefits
New Eastbound 4th Avenue Off-Ramp 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 4 th Avenue South.	The new ramp provides eastbound travelers on the West Seattle Bridge with direct access to downtown Seattle via 4th Avenue South. An improvement in its own right, this access will be critical during the replacement of the Alaskan Way Viaduct, when SR-99 northbound will be inaccessible from West Seattle. 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.
Changes	Benefits
Widening of Spokane Viaduct (Upper Roadway) The upper roadway between 6th Avenue South and East Marginal Way will be widened to the north by 41 feet.	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 Westbound On- and Off-Ramp at 1st Avenue The existing ramp at 4th Avenue S. for westbound traffic will be replaced by a new ramp at 1st Avenue S., built to current design standards.	Relocating the westbound ramps to 1st Avenue S. will improve westbound traffic flow and safety. (The existing ramps at 4th Avenue 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 will allow for smoother and much safer entry to and exit from the upper roadway.)
Changes	Benefits
Upper Roadway Deck Improvements The existing upper roadway deck will be repaved and variable message signs will be installed.	The variable message signs will provide advance notice of serious congestion resulting from accidents or special events. That advance notice and a smoother roadway will help drivers choose their route and reach their destination more safely.
Seismic Strenghtening Seismic strengthening of the viaduct will be completed.	The stronger structure will reduce the likelihood of serious damage to the structure in the event of a major seismic event.
Lower Roadway Reconstruction 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	Creating a formal sidewalk on the north side of Spokane Street will serve as a link for bicyclists between the bike paths west of East Marginal Way and the planned E-3 Busway bike path, and will facilitate pedestrian traffic.
Planted Median on 4th Ave A planted median will be constructed on 4th Avenue South north of Spokane.	The planted media will separate traffic effectively, while also bringing green growth to an industrial area.

Construction Impacts:

The main construction impact will be closure of the lower Spokane Street roadway between 1st Ave S and 4th Ave S for most of the project. This will require detour routes to be established for both eastbound and westbound surface-level traffic. Additionally, most parking under the viaduct between East Marginal Way and 6 th Avenue South will be eliminated during construction.

The principle detour route for eastbound traffic will be north along East Marginal Way, then east on South Hanford St., north on 1st Ave S. and east on Lander Street. Westbound traffic will be diverted north on 6th Ave. S. to S. Lander Street where the reverse of the east bound route will lead to S. Spokane and the West Seattle Bridge. Signals along these routes may be adjusted to reduce congestion, but greater congestion and slower transit times should be expected.

A series of slides has been developed to present the principle detour route for the project throughout the projected construction schedule.

Projected Schedule:

• Utility relocation work — July 2008 through October 2008 (eastbound lower roadway closure from 1st to 4 th Ave South begins)
• New 4th Avenue Off-ramp construction: — November 2008 through Spring 2010
• Spokane Viaduct Widening: Spring 2009 through Summer 2011.

How to Stay Informed:

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

List-serve 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 website and the information will be distributed via the City's list-serve.

Area-wide fliers: 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.

Website updates: Information on the project will be maintained here, including fliers and newsletters will be available on-line.

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 considering other means of providing information about the project and how to minimize construction related impacts, including a dedicated phone line recording, text messages, and/or citizen band (CB) radio reports on the current status and upcoming activities. 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 Art Brochet, Project Communications Liaison, at 206-547-1008 or by email at art@urbanrelations.com. Alternatively you may contact Stuart Goldsmith, Project Manager, at 206-615-0860, or by e-mail.