SR 99

Route ID
099

UPDATE - Announcing ‘Conechella:’ Multiple highway closures across greater Puget Sound weekend of Aug. 22-25

UPDATE: The series of westbound SR 18 lane, ramp and directional closures has been postponed and will be rescheduled at a later date. The scheduled work on the SR 99 First Avenue Bridge has also been canceled. The information has been removed in the news release below.

What a blast: Project to improve traction in SR 99 tunnels in Seattle

SEATTLE – It’s about time for people who use the State Route 99 tunnel under downtown Seattle to get a grip.

Beginning Monday night, Aug. 18, contractor crews working for the Washington State Department of Transportation will texturize lanes in the tunnels to improve traction for vehicles.

The quick-moving project requires up to five nightly closures in each the northbound and southbound tunnels. Work is expected to wrap up before Labor Day weekend.

Start planning now: Major highway closures, lane reductions around Puget Sound Oct. 11-14

Update: Oct. 10, 2024 - I-5 lane closures in Seattle will now include northbound lanes between mid-Boeing Field and the West Seattle Bridge. The updated information is reflected in the release below.

Update: Oct. 9, 2024 - The hours for the I-405 overnight lane reductions and ramp closures have changed. Note the lane closures will occur 8 p.m. Friday, Oct. 11 to 8 a.m. Saturday, Oct. 12. Ramps will be closed from 11 p.m. Friday to 8 a.m. Saturday. This updated information is reflected in the release below.

SR 99 tunnel to close for first two weekends in October for inspection in Seattle

SEATTLE – Both directions of the State Route 99 tunnel in Seattle will close the first two weekends in October for its first six-year inspection. The tunnel opened to travelers in February 2019 to replace the Alaskan Way Viaduct and provide safety and mobility improvements along Seattle's central waterfront. 

Closure details

From 10 p.m. Friday, Oct. 4, until 6 a.m. Saturday, Oct. 5, and from 10 p.m. Friday, Oct. 11, until 6 a.m. Sunday, Oct. 13, both directions of the SR 99 tunnel will close.

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.