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SR 99 – Spokane St. Br. to Alaskan Way Viaduct Concrete Pavement Rehab


December 2014

  • This project was declared operationally complete on Oct. 2, 2014. Operationally complete means the roadway is open to traffic and the majority of work is complete.
  • For other closures on SR 99 for other projects, check the Seattle construction website.
  • This project is similar to other pavement repair projects we have done in King County near Kent and Seattle.
  • Sign up to receive email updates about this project and other Seattle area topics.


In summer 2014, contractor crews will replace or repair 81 concrete panels in both directions of State Route 99, between South Spokane and South Holgate streets in Seattle’s SODO neighborhood. Crews also will grind down 198,000 square feet, approximately three and a half football fields, of wheel ruts.

This project is similar to concrete grinding and replacement work we have done on I-5 in Kent, Seattle near the Ship Canal Bridge, and I-405 near Bellevue.

What can drivers expect?
• Weekend and weeknight lane closures in both directions of SR 99 between South Spokane and South Holgate streets

Why is WSDOT repairing and replacing concrete panels from Spokane St. to Alaskan Way Viaduct?

Forty years of winter weather and increasingly higher traffic volumes have resulted in cracked, rutted and bumpy pavement on SR 99 south of the Alaskan Way Viaduct. The concrete panels that make up this stretch of road lasted longer than engineers thought they would, however now it’s time to grind down the ruts and replace the most severely damaged sections.

Repairing damaged concrete panels extends the life of SR 99.
• Cars, trucks and vehicles of varying weights pass over panels causing the concrete to flex. Cracked panels flex leading to more cracking and damage.
• Normally, concrete panels expand and contract with seasonal temperature change. Cracked panels, however, become increasingly damaged when moisture freezes and thaws in the existing cracks.

Repairing cracked and rutted concrete panels helps keep drivers safe. 
• Water can pool in rutted sections of road. Drivers can lose traction when passing over pooled water at high speeds.
• Repairing concrete reduces bumps and ruts making for a safer, smoother ride.

Over the years, maintenance crews have made temporary repairs to problem areas. However, the pavement is failing faster than crews can keep up and it’s time for longer lasting repairs.

The End Result
Crews will repair 81 concrete panels along SR 99 between between South Spokane and South Holgate streets in Seattle’s SODO neighborhood.This project helps extend the life of SR 99, and provide a safer, smoother ride for drivers.

Project Benefits
Improved Safety – Replacing cracked concrete panels and grinding out potholes and wheel ruts makes for a smoother safer ride for drivers

Extends the life SR 99 - Reduces the need for emergency repairs, which are costly to taxpayers and can cause unwanted congestion during rush hour.

What is the project timeline?
• March 24, 2014 – The contract was awarded to Penhall Company
• Summer 2014 - Construction starts
• Winter 2014 - Expected completion 

Financial Information

Financial Data for PIN 109936G
Funding Source Amount ($ in thousands)
2003 Gas Tax (Nickel Funding) $0
2005 Gas Tax (TPA) $0
Pre-Existing Funds (PEF) $1,393
Total $1,393

Project signage will reflect the cost of construction engineering, project bid award and sales tax.

How can I get more information?
John Chi
WSDOT Project Engineer 
Phone: 425-225-8741

Kris Olsen
WSDOT Communications
Phone: (206) 440-4704

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