Crews quiet the “thump” on I-405 in south Bellevue


Beginning today drivers will no longer hear the “thump, thump, thump” on I-405 in Bellevue as crews completed an extensive pavement repair process on I-405 as part of the I-405, South Bellevue Widening Project.

Over the past two summers, crews replaced 35 damaged concrete panels, repaired the joints between concrete panels (eliminating the thumping sound), and ground the pavement to a smooth and level driving surface.

“Now drivers will enjoy a smoother, quieter ride,” said Stacy Trussler, WSDOT Deputy Project Director. “We’re also extending the life of the pavement and getting more out of our original investment.”

Crews needed to repair the pavement because it was more than 40 years old, with significant wheel ruts due to traffic over time. Left unaddressed, in rainy weather, wheel ruts can cause vehicles to “hydroplane,” or lose contact with the road.

“Some drivers have wondered about the ‘patchwork pavement’ as the pavement repair progressed,” Trussler said. “To repair the joints, crews first cut slots between the pavement panels, inserted steel dowel bars for stability, and covered the bars with concrete. Finally, they ground the concrete to smooth it.”

The repaired sections are on both directions on I-405 from Southeast Eighth Street to Coal Creek Parkway. Most of the work took place during overnight lane closures on the freeway. Pavement repair crews also worked during two weekends in August, taking advantage of closures of southbound I-405 for removal of the Wilburton Tunnel. This helped speed the work and minimize the need for about three weeks of nighttime lane closures.

In summer 2009, crews will install test sections of quieter pavement along I-405 in south Bellevue, similar to what has been applied on SR 520. WSDOT will study the test sections to see how quieter pavement performs in the Pacific Northwest's driving and climate conditions.

When complete in 2009, the I-405, South Bellevue Widening project will help relieve congestion at one of the worst I-405 bottlenecks – the drive in and out of downtown Bellevue. For more information or to sign up for e-mail updates, visit