Date:  Monday, July 20, 2009

Contact: Mike Murphy, WSDOT Communications, 206-440-4699
Jeff Switzer, WSDOT Communications, 206-440-4700

SEATTLE – Drivers who endured backups for the past two weeks on westbound I-90 between Bellevue and Seattle are seeing a typical commute today. Over the weekend crews wrapped up a project to replace two aging and cracked expansion joints on the I-90 floating bridge. The westbound mainline lanes reopened Saturday morning, even earlier than expected. WSDOT negotiated a shorter construction schedule that required reopening the lanes by Monday morning.

WSDOT and General Construction, Co. replaced the massive steel joints in the I-90 express lanes in May and the westbound mainline in July. During the work in July, all westbound I-90 traffic was funneled into the two express lanes around the clock.

“The drivers who have endured a long summer of work on I-90 deserve a big thank you for their patience. Contractor crews used the lessons learned from the joint replacement in May to speed up the work in July. We know that I-90 is a vital transportation corridor that we wanted to turn back to the commuters as quickly as possible to keep the economy and the region moving,” said Paula Hammond, Washington Transportation Secretary.

Traffic during the closure
Traffic engineers used data gathered from in-road sensors in the weeks before the work to calculate potential delays. Those numbers showed possible delays of an hour or more between Issaquah and Seattle. Thanks to drivers who changed their habits, the travel times were far less on most days, averaging about 30 minutes in the mornings and 45 minutes in the afternoons – about double the average travel time. The longest westbound morning commute between Bellevue and Seattle was 54 minutes on Tuesday, July 14. The longest afternoon commute was 85 minutes on Thursday, July 9. On some days, half the usual number of vehicles used the I-90 floating bridge, resulting in shorter delays. We saw travel times rise on SR 520 across the lake, and I-405 faced backups during construction. Many drivers also chose to leave early, before 6:30 a.m., to beat the morning rush hour altogether.

“We saw the Eastside morning commutes pick up at 6 a.m. They usually pick up around 7:30,” said WSDOT Assistant Regional Administrator Russ East. “We have drivers to thank for helping to minimize the congestion.”

Contractor crews worked 24 hours most days, chipping away concrete, cutting out the old joints, lowering in the new joints with a huge crane and pouring new concrete. Good weather and experience led the contractor and WSDOT to draft a solid plan for these two weeks of construction. To speed up the project, WSDOT paid the contractor $510,000 to finish by July 20. To meet that deadline, the contractor did early nighttime sawcutting on the bridge, hired more crews and coordinated two simultaneous work zones on the floating bridge.

Regional teamwork
This project required careful planning with Metro Transit, Mercer Island and Bellevue officials, and emergency service providers who depend on I-90 daily. To help buses and vanpools avoid traffic backups, WSDOT restriped transit access to the I-90 express lanes from Bellevue Way SE. Metro rerouted its I-90 corridor buses on this route to save time. To help prevent traffic backups in Mercer Island’s business district, police officers sent drivers through a detour route designed with help from Mercer Island officials if morning traffic was too heavy for the freeway on-ramps.

To help ambulances and fire engines quickly bypass congestion and construction closures, emergency providers had maps, photos, diagrams and a connection to WSDOT’s 24-hour traffic center. Eastside dispatchers checked in regularly to track congestion delays on the floating bridge. WSDOT planned ahead with fire chiefs for possible emergency scenarios, which eased concerns about limiting cross-lake access to Harborview Medical Center in Seattle.

Remaining work
Construction crews are closing the I-90 express lanes in between the morning and evening commutes this week to replace concrete barrier on Mercer Island. The barrier was removed two weeks ago to allow two lanes of traffic to merge from the I-90 westbound mainline lanes to the I-90 express lanes while the crews replaced the expansion joints on the floating bridge.

During the evening commute and into the evening, traffic will be narrowed to one lane in the I-90 express lanes on the east side of Mercer Island.

• From 9 a.m. to 2 p.m., Monday, July 20 through Friday, July 24: The I-90 express lanes will be completely closed for construction. 
• From 2 p.m. to 10 p.m., Monday, July 20 through Friday, July 24: The left I-90 express lane will be closed for construction on Mercer Island from Island Crest Way to East Mercer Way when traffic is heading in the eastbound direction.

WSDOT bridge engineers were concerned the cracked expansion joints could pose a safety risk if not replaced. For videos, photos and other project information, on the $8.5 million project, please visit www.wsdot.wa.gov/projects/i90/HomerHadleyBridgeRepair.

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