300 concrete panels to be replaced on I-5 between Northgate and Ballinger Way

Crews pulling up concrete panels on I-5 near Tukwila

Beginning in July, crews will replace more than three hundred concrete panels and grind out cracks and bumps on I-5 between Northeast 117th Street near Northgate and SR 104 in Shoreline. The work will help extend the life of the road and improve driver safety. The work will require overnight closures of multiple lanes and ramps.

The pavement on I-5 through King County was first installed between 1962 and 1965. It was designed to last through the 1980s. High traffic volumes, age and weather have all contributed to the telling signs of failing pavement - cracks, bumps and what pavement engineers call spalling. Spalling is pavement that is flaking, chipping or crumbling apart. However you might describe it, the pavement is failing and it is time for longer lasting repairs.

Simply laying asphalt on top of the existing concrete isn’t enough because of high traffic volumes and numerous bridges. Plans are to remove the existing nine-inch thick pavement on the freeway and replace it with thirteen inches of pavement reinforced with steel bars at the joints. The thicker concrete would ensure at least another 40 years of service, and the bars would help the roadway behave like a single unit rather than individual concrete panels. This would minimize the rough "thump, thump, thump" motorists now hear and feel as they drive on I-5 through Seattle.

A key part of the project is to keep 250,000 vehicles moving during pavement reconstruction with as minimal a disruption as possible.

Drivers are urged to plan ahead during this busy construction season. WSDOT offers tools and resources to help give travelers an advantage and take the edge off road closures:

• Check the Seattle traffic page before hitting the road
• Use travel alerts to get real-time information about blocking incidents
• Download WSDOT’s mobile app
• Follow @wsdot_traffic on Twitter
• Call 5-1-1 for traffic updates
• Check the What’s Happening Now website for updates