February 2012
- Visit what's happening now for a snapshot of the latest construction and special event activity in the south end.
- We're rebuilding East Marginal Way South in front of the U.S. Coast Guard. See the latest photos.
- Get a bird's eye view of construction as it unfolds with our live construction cameras.
- The southern mile of the viaduct is long gone. In case you missed it, take a gander at our Flickr photos of the demolition.
Overview
The State Route 99 Alaskan Way Viaduct carries thousands of vehicles to and from downtown Seattle, two major stadiums and the Port of Seattle each day. Its increasing age and vulnerability is apparent by crumbling concrete, exposed rebar, weakening column connections and deteriorating railings.
In fall 2011, we demolished the viaduct's south end section and replaced it with the first of two new bridges. Construction on the second bridge, which will eventually carry northbound SR 99 traffic, is currently underway.
This project is part of the Alaskan Way Viaduct Replacement Program.
Why is WSDOT
replacing the south end of the Alaskan Way Viaduct?
The section of the viaduct between South Holgate and South King streets was built in unstable soil that could liquefy in an earthquake, and its columns did not reach deep enough into solid ground. The viaduct's south end was vulnerable in an earthquake and needed to be replaced.
The End Result
The southern mile of the Alaskan Way Viaduct is being replaced with two side-by-side bridges that meet current earthquake standards, have wider lanes and improve mobility for people and goods in the south of downtown area. This project will connect to the SR 99 tunnel.
Additionally, a new overpass at South Atlantic Street will help keep freight and other traffic moving when trains are blocking the intersection with Alaskan Way South.
Project Benefits
- Safety: The new roadway will meet current earthquake design standards. Wider lanes and new shoulders will provide better emergency access and give drivers more room to maneuver.
- Mobility: The new section of SR 99 will have three lanes in each direction south of South Royal Brougham Way and new on- and off-ramps near the stadiums. A new South Atlantic Street overcrossing will improve connections between the Port of Seattle and major freeways by allowing traffic to bypass passing trains.
What is the project timeline?
2001: Nisqually earthquake damages viaduct. Alaskan Way Viaduct replacement begins.
2007: Replacing the viaduct between South Holgate Street and South King Street is identified as one of several projects that could be built as the decision process continues for the viaduct's central waterfront section.
2008: Release Environmental Assessment for South Holgate Street to South King Street Viaduct Replacement Project.
2009: Release Finding of No Significant Impact; crews remove electrical lines from south end of the viaduct in preparation for construction.
2010: Utility relocation complete. Road and bridge construction begins.
2011
February
- New north-south street (East Frontage Road) opens between South Royal Brougham Way and South Atlantic Street, just to the east of SR 99.
- Crews demolish First Avenue South on-ramp to northbound SR 99.
May
- SR 99 between the West Seattle Bridge and Seattle's sports stadiums reduced to two lanes in each direction during construction.
- Crews set first girders for the new southbound SR 99 bridge.
June
- Gov. Gregoire announces that demolition of the viaduct's south end will begin in October 2011, six months ahead of schedule.
October
- SR 99 closes for a week while demolition of the viaduct's south end begins.
- Complete four-lane construction bypass connecting the viaduct's central waterfront section to the new SR 99 bridge.
November - December
- Complete demolition of the viaduct south of Railroad Way South. SR 99 remains open during demolition.
- Begin construction of second bridge.
2012
Summer
- Begin work on South Atlantic Street overcrossing.
2013
- New SR 99 between South Holgate and South King streets complete.
- South Atlantic Street overcrossing complete.
Financial Information
Project budget: $394.8 million
The project includes three separate contracts:
- Stage 1 moved utilities that were in the way of construction. Work started in 2009 and was completed in 2010.
- Stage 2 replaces the south end of the viaduct between South King Street and South Holgate Street and improves nearby city streets.
- Stage 3 builds an elevated bypass of the BNSF tail track on South Atlantic Street, near the Port of Seattle's Terminal 46 entrance.
This project has committed funding from the state gas tax and federal sources.
How can I get more information?
Contact:
Travis Phelps
Communications
Phone: 206-805-2861
Mobile: 206-462-0554
E-mail: PhelpsT@wsdot.wa.gov
or
Greg Phipps
Communications
Phone: 206-805-2862
E-mail: PhippsG@wsdot.wa.gov
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