February 2013
SR 520 open houses
- You're invited to SR 520 open houses! Join us to learn latest about current and future construction.
- Meeting details:
Bellevue
4:30-7:30 p.m., Tuesday, Feb. 5, 2013
North Bellevue Community Center
4063 148th Avenue Northeast
Bellevue, WA 98009
Seattle
4:30-7:30 p.m., Wednesday, Feb. 6, 2013
St. Demetrios Church
2100 Boyer Avenue East
Seattle, WA 98112
January 2013 Pontoon update
All interior precast panels have been set inside the second cycle of pontoons in Aberdeen. Work is well under way on the three longitudinal pontoons, two supplemental stability pontoons, and one cross pontoon in the basin.
Current work includes:
- Pouring concrete for keel slabs.
- Setting forms for pontoon walls and top slabs.
- Installing reinforcing steel.
- Continuing to build interior precast panels for the cycle 3 pontoons.
Check out recent photos of the progress.
New pontoon update page
Why is WSDOT
building new pontoons?
Overview
The aging SR 520 floating bridge on Lake Washington is vulnerable to windstorms and needs to be replaced. Moving forward with pontoon construction is a critical step towards construction of the new SR 520 bridge. The $367.3 million Pontoon Construction Project broke ground in February 2011 at a 55-acre site in Aberdeen. Since the groundbreaking, WSDOT and contractor Kiewit-General (K-G) have built a casting basin facility featuring a concrete batch plant, on-site water treatment, and a 4-acre casting basin, where pontoon construction is under way.
By the Pontoon Construction Project’s completion date in 2014, crews will have constructed 33 pontoons, 21 of which will be 360 feet long, 75 feet wide, and nearly 30 feet tall. These pontoons are the largest ever built in Washington. Once complete, each batch of pontoons will be floated out of the casting basin, inspected, and towed into place on Lake Washington where they will serve as the floating foundation for the new SR 520 bridge.
The End Result
WSDOT is moving forward with pontoon construction as part of the replacement of the SR 520 bridge. Pontoons will be built in six cycles in the casting basin in Aberdeen. After each cycle is completed, the pontoons will be inspected, outfitted, and towed to Lake Washington, where they will be connected together to form the floating foundation for the new SR 520 bridge.
Project Benefits
The pontoons for the SR 520 bridge will improve safety and reliability. They will be designed and built to:
- Withstand a 1,000-year earthquake event.
- Withstand windstorms up to 89 mph.
Once complete, the new pontoons will support a wider, six lane roadway with dedicated transit/HOV lanes, wider, safer shoulders, and a 14-foot-wide bicycle/pedestrian path.
What is the project timeline?
- 2009 - Innovative pontoon construction testing.
- 2010 - Publish draft environmental impact statement.
- 2010 - Issue final environmental impact statement.
- 2011 - Receive Record of Decision from FHWA.
- 2011 - Begin and complete casting basin facility construction.
- 2012 - Begin pontoon construction.
- 2014 - Complete pontoon construction.
Financial Information
Project signage will reflect the cost of construction engineering, project bid award and sales tax.
The project is funded through the following sources:
With the passage of ESHB 2211 in the 2009 legislative session, WSDOT has been authorized to collect tolls on the SR 520 floating bridge since 2011. This will expedite the replacement of the SR 520 floating bridge and has allowed us to move forward with construction.
How can I get more information?
Contact:
For comments and questions about the project, or to be added to the mailing list or e-mail list, please e-mail pontoons@wsdot.wa.gov.
To listen to a recording of the latest project information and leave a verbal comment or question, please call the project hotline at 1-360-591-8012.
To contact the project office by mail:
Pontoon Construction Project
999 3rd Avenue, Suite 900
Seattle, WA 98104
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