The Washington State Department of Transportation will team up with a Mukilteo contractor on repairs that could mean long delays for drivers heading north into downtown Seattle this August.

The state and Concrete Barrier Inc. will help protect drivers and extend the life of the freeway by paving more than one mile of northbound Interstate 5 and replacing failing bridge expansion joints between Spokane Street and I-90. The transportation department awarded the construction contract to Concrete Barrier Inc. for a winning bid of $11,917,777.

These repairs will significantly affect I-5 drivers and transit users, particularly during 19 continuous days of intense construction from Aug. 10 to Aug. 29 when crews will close several lanes of northbound I-5 at all times, leaving only two or three lanes open to workday traffic. Crews will repair the expansion joints on the southbound bridge using overnight closures starting in July. Concrete Barrier Inc. will complete the southbound repairs before the August closures begin.

The state transportation department included significant financial carrots and sticks in the contract to help ensure that crews complete the August closure as quickly as possible. Concrete Barrier Inc. will receive a $100,000 bonus each day they complete the August work ahead of schedule. The contractor will pay a $100,000 penalty each day they exceed the 19-day schedule.

Although state transportation department is working with the City of Seattle and other local communities, businesses and transit agencies to help keep traffic moving during construction, lengthy backups and significant delays are expected. The closures will have a substantial effect on commuters heading into downtown from West Seattle, South King County and Pierce County, and will push traffic onto other routes, including I-405, State Route 99 and city streets in Georgetown, Sodo, Rainier Valley and Beacon Hill.

Drivers also can expect periodic closures of the Spokane Street and Columbian Way on-ramps to northbound I-5 and the northbound I-5 exits to Fourth Avenue S., I-90, and James, Madison and Dearborn streets.

The contract award announcement is a reminder that drivers have just three months to take steps to ease their commute this August:

- Arrange to carpool or vanpool

- Practice taking the bus or train

- Make arrangements to work from home or another alternate worksite

- Discuss altering your work schedule to come in earlier or later than normal

- Try alternate routes

- Keep up to date on the project by subscribing to state transportation department's I-5 Seattle E-mail Alerts and by bookmarking state transportation department's project Web page

- Plan a vacation between Aug. 10-29

I-5 from Spokane Street to the I-90 interchange is an elevated bridge that is more than 40 years old. It's one of the busiest sections of freeway in Washington and the daily pounding has taken its toll. The expansion joints connecting the concrete spans that make up the freeway are failing and potentially pose a serious risk to drivers. Collisions and major traffic back-ups are a growing risk as the top steel plates of these joints detach more and more frequently.