Southbound I-5 off-ramps to Mercer Street in Seattle closing four consecutive weekends starting Sept. 8

Closure includes express lanes off-ramp to Mercer Street

SEATTLE – Travelers heading to Seattle’s South Lake Union area will soon need to prepare for four consecutive weekend closures of the southbound Interstate 5 off-ramps to Mercer Street.

Contractor crews working for the Washington State Department of Transportation will close both the mainline and express-lane off-ramps to Mercer Street beginning at 10 p.m. Friday until 5 a.m. Monday the weekends of Sept. 8-11, Sept. 22-25, and Sept. 29-Oct. 2.

The weekend closure for Sept. 15-18 is now a 21-hour closure scheduled to begin at 10 p.m. Friday, Sept. 15 until 7 p.m. Saturday, Sept. 16.

The Sept. 29 - Oct. 2 weekend closure is postponed. A new date will be announced soon.

During the closures, crews will repave sections of the roadway, perform utility and drainage work, and continue building a new retaining wall. These closures help keep the project on schedule for spring 2024 completion.

This work is part of the SR 520/I-5 Express Lanes Connection Project.

Stay up to date

Some of the closures are weather-dependent. The public will be notified of any changes to the schedule on the SR 520 Construction Corner webpage. People can also get real-time traffic information from the WSDOT app or by calling or texting the 24-hour hotline at 206-316-2559.

Slow down on ice and snow.

It's easier to skid or lose control traveling at higher speeds. Give yourself more time to stop.

Carry chains, practice installing them.

Winter conditions could mean chains are required on your route. Practice putting them on your vehicle ahead of time.

Pack your winter car kit.

Carry extra supplies like warm clothing, ice scraper and brush, jumper cables and other emergency items.