“There’s no question that traffic is going to be bad.”

That’s not something you want to hear from a transportation engineer.

But that was the message Washington State Department of Transport’s (WSDOT) Russ East delivered to the Issaquah City Council on Tuesday night ahead of maintenance work on the Interstate 90 floating bridge in May and July.

A number of westbound lanes will be out of action from May 4 to 23 and from July 5 to 28, as the department carries out work to repair cracks in the expansion joints underneath the bridge, work that is felt to be too urgent to delay any longer.

The snap shot for commuters is this: traffic will be bad in May, and much worse in July, between the typical commuter peak hours of 7 – 10 a.m. and 4 – 7 p.m.

“Our engineers are describing it like this – in May, it will be like when the Mariners were winning, and you were trying to get around downtown Seattle,” East said. “In July, it will be like 520 on a bad day.”

It is expected that traveling west between Bellevue and Seattle during peak hours in May will take about 30 minutes.

In July this trip is expected to take about 50 minutes, as the existing five lanes will be reduced to two.

East said that the trip from Issaquah to Bellevue could add about 20 minutes to that, depending on the amount of traffic backup.

He added a warning that these figures were based on the scenario that 50 percent of commuters would chose to take a different route.

If this doesn’t eventuate, the waits will be longer.

Councilman Fred Butler asked whether or not there would be concessions made to public transportation, in terms of lane usage or other considerations to make travel on buses more expedient.

“They will be given partial priority,” East replied, adding that although the department could not designate an entire lane for public transit, they would try to give transit “cue jumps,” when returning from the Bellevue Park and Ride and around the traffic exits/entrances around Mercer Island.

“But buses will be impacted just like everyone else,” he said.

East said that bus companies had indicated to him they would make alterations to their routes to try and avoid traffic build-ups.

There could also be related slowdowns on state Route 520, Interstate 405 and Interstate 5.

“If you regularly use I-90 or 520 to cross the lake, start making plans now for dealing with the projected congestion,” East said.

Bike and pedestrian paths across the bridge will remain open throughout the project.

Information about the park-and-rides and help in planning a bus trip can be found on Metro Online.

King County Metro and WSDOT are offering special vanpool and carpool incentives with a federal grant designed to ease commute congestion.

The incentives are open to commuters starting a new Metro vanpool on routes that routinely cross the I-90 or SR-520 bridges in either direction or travel on I-405.

Eligible vanpoolers in new groups that start between May 1 and July 1 will receive free vanpool fares for three months.

Five or more commuters who share the ride to a park-and-ride can get signed, reserved spaces at the lot or garage by forming a Metro vanshare group. WSDOT will pay the new vanshare group’s fees for three months.

Carpoolers also earn incentives. A $20 MasterCard gift card will be given to the first 3,000 new registrants on RideshareOnline.com or current registrants who go into the system and request an updated list of potential carpool partners.

Check RideshareOnline for details about the incentives.

For more information on the I-90 floating bridge work, go to www.wsdot.wa.gov/Projects/I90/HomerHadleyBridgeRepair/