Get ready: I-5 lanes to close in August, major backups expected

Summertime traffic will likely get far worse with 19 straight days of lane closures on northbound Interstate 5 just south of downtown Seattle.

The state Department of Transportation (DOT) will close at least two lanes over 1.13 miles, triggering big backups on I-5 and on other roads, including Interstate 405 and surface streets south of the city.

If drivers don't seek alternate routes, backups on northbound I-5 could reach Tacoma, DOT officials said today.

Starting Aug. 10, two to three lanes at a time will be closed all day between the West Seattle Bridge and the I-5/I-90 interchange while crews replace metal joints in the roadway.

DOT officials said these joints are outdated and may fail, leading them to pop up in the middle of the highway.

The agency strongly encourages commuters to take alternative routes to ease the traffic congestion.

About 130,000 drivers use this section of I-5 every day, said Laura Penning, a spokeswoman for the DOT.

The agency said it hopes half of all motorists will try going a different route during those 19 days, she said. Even if they do, the DOT expects congestion between 4 a.m. to 11 p.m.