Thanks to good weather and swift construction crews, the I-90 floating bridge express lanes will reopen Saturday – a week sooner than previously scheduled.

That means Monday morning’s commute will be closer to normal with buses and carpools again able to use the I-90 floating bridge express lanes.

“Our contractor crews worked hard to finish this project quickly so drivers didn’t have to sit in construction congestion any longer than absolutely necessary,” said Russ East, Assistant Northwest Region Administrator. “I want to thank drivers for their patience during this important work.”

Construction on the I-90 express lanes forced cars and buses into mainline traffic and caused some commute delays until Eastside drivers shifted their schedules. On Friday, drivers who want to avoid westbound backups from Issaquah to Seattle still need to travel well before the 7-9 a.m. peak commute.

The work on the I-90 express lanes was crucial for keeping the floating bridge safe for drivers. The old joints, installed about 20 years ago, were cracked and engineers said the joints threatened to pop up into traffic and needed to be replaced. The I-90 express lanes closed May 3 for major surgery. Crews were given fewer than three weeks to chip concrete and cut free two massive steel expansion joints and replace them with new stronger joints.

The work was expected to be completed by May 23, a date set to include the tough job of removing and replacing the joints, as well as possible delays from rough weather and unforeseen demolition and construction challenges.

General Construction Co. took several key steps to make the roadwork go more swiftly, and crews:

* Worked 24 hours a day except for one day instead of previously planned 20-hour days.

* Made deep advance saw cuts in the I-90 express lanes for four days between 10 a.m. and 2 p.m. before the May 4 closure. This made it easier to chip out the concrete holding the joints in place.

* Spent a lot of time carefully coordinating two simultaneous work zones one mile apart on the floating bridge. The contractor created and followed an excellent work plan, state officials say. The plan also included protecting air and water quality and minimizing noise for nearby Mercer Island and Seattle residents.

* Aside from a 12-hour shift dealing with stormwater and weather, crews encountered no unexpected construction problems during the concrete chipping, joint cutting or 40-ton joint installations.

Only a few tasks remain to wrap up this first phase of the project. Crews must remove forms, conduct tests of the joints and restripe the lanes. Traffic is expected to be allowed in the I-90 express lanes sometime Saturday.

“We hope that the lessons learned installing these first two joints help shorten the construction schedule when we replace the next two joints on the I-90 floating bridge in July,” East said. Crews will completely close the I-90 westbound mainline July 5-28 to chip free and replace even larger expansion joints. Drivers need to continue to make plans to avoid potentially unprecedented gridlock on I-90 and other regional freeways in July.

The entire $8.3 million I-90 expansion joint project supports an estimated 80 jobs.

Work on the I-90 express lanes forced drivers and buses to share three westbound lanes into Seattle. That initially caused freeway backups to Issaquah during the morning peak until drivers started spreading out their commute times.

In July, those same westbound drivers will be funneled into just the two express lanes. Travel times could stretch to an hour or more from Bellevue to Seattle during the morning and evening peak commute times.

Drivers can start planning now to commute very early, ride a bike across I-90, work from home or choose alternate routes. Drivers have until June 8, to sign up for a vanpool and receive three free months.