Transportation managers are pleading for people to reduce their trips as the state closes the Alaskan Way Viaduct for good on Jan. 11 but doesn't open the replacement Highway 99 tunnel for another three weeks.

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Transportation managers are asking people to reduce their trips as the state closes the Alaskan Way Viaduct forever on Friday night but doesn’t open the replacement Highway 99 tunnel for another three weeks.

Here’s what travelers can expect.


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No temporary lane capacity will be added to other highways during the three-week Highway 99 closure.

The state will convert a carpool lane of Interstate 5 to general traffic, southbound from Mercer Street to Corson Avenue, where public transit rarely goes anyway. This tweak might reduce delays beneath the downtown convention center, because solo drivers who merged in from Mercer can remain in the left lane.

Two more incident-response trucks will be stationed along state highways, bringing the total to 21 weekdays between Federal Way and the Canadian border.

Are you ready? Three-week Highway 99 closure downtown will push our patience to the limit

Recently, the state removed barrels that caused awkward merging where Interstate 90 meets northbound Interstate 5, and created a bus-bypass lane on the left shoulder, southbound from Lynnwood to Mountlake Terrace.

Two existing viaduct ramps closed early, Jan. 4, where drivers entered or exited the viaduct near the Sodo stadiums. After the anticipated tunnel opening Feb. 4, the new northbound exit in Sodo won’t be open for perhaps another week. During that time drivers coming from West Seattle must enter the 2-mile tunnel and not exit until the new South Lake Union interchange.

Detours and slowdowns

On the Duwamish industrial segment of Highway 99, also called East Marginal Way South, incoming traffic must exit at Spokane Street, into a single lane through railroad crossings and a truck overpass. Drivers who go this far can expect delays at the exit, or afterward when they detour east to First or Fourth avenues south in Sodo.

On the north side, Aurora Avenue North will crunch from three lanes to one each direction, shared with buses, in the South Lake Union area.

As congestion cascades outward, delays on I-5 might average 20 minutes longer than usual, based on previous viaduct closures. Interstate 405 will likely get slower through the Bothell and Renton chokepoints.

Local traffic does have a First Avenue South ramp available to the West Seattle Bridge for the evening exodus. South Lander Street is blocked for overpass construction, which will complicate Sodo maneuvers.


King County Water Taxi will add the 245-passenger San Juan Clipper on its West Seattle-to-downtown route, to join the 278-passenger Doc Maynard, from Jan. 14 to March 27. Sailings will be every 15 or 20 minutes. Basic fare is $5 each way with an adult ORCA card. Boats depart Seacrest Dock next to Marination Ma Kai restaurant, and arrive downtown next to the state ferry terminal.

The Sally Fox, with 278 seats, will return from winter repairs to serve the Vashon route, spokesman Jeff Switzer said Monday, while the smaller Spirit of Kingston will serve as a backup for Vashon or West Seattle service.

Free shuttle buses, leaving the water-taxi dock as Route 773 to Alaska Junction and Route 775 to the Alki and Admiral areas, will increase. An unpaved park-and-ride lot next to Salty’s Restaurant will hold 40 cars, and another lot for 250 more cars will operate with shuttle service at Pier 2 near the Harbor Avenue 7-Eleven store.

Washington State Ferries remain on normal schedules. The overhead walkway from Colman Dock to Marion Street will stay open.

Light rail and Sounder trains

Link light rail already carries its ideal capacity of 150 per railcar on average, half seated and half standing. Any more people, and you must jostle to board the two- or three-car trains.

“Whatever wiggle room we have will quickly be eaten up,” said spokeswoman Kimberly Reason. The fleet is maxed out until a new order of 122 railcars arrives, for the Northgate extension in 2020-21.

Sounder commuter trains will stay on regular schedule with 10 morning trips from Tacoma or Lakewood into Seattle, and 10 trips south in evenings, plus three reverse-commute trains each way. The seven-car trains typically run 65 percent to 80 percent full, leaving 150 or more seats per train available.

The north line from Everett operates four trips each direction.

Buses, Aurora Avenue

Metro will divide 20 standby buses between Aurora and West Seattle, all day, to assure frequent service and possibly hundreds of additional trips. Some 31,700 daily passengers ride routes E, 5, 26 and 28 on Aurora Avenue, where buses and general traffic will squeeze through a single Aurora lane each way, just south of Mercer Street.

Metro is considering detours that turn buses right at Valley Street, to enter downtown on Fifth Avenue North. The city hasn’t committed to appropriating road space but says that’s an option at Valley or other tight spots, based on conditions.

Buses, West Seattle/Burien

A dozen viaduct bus routes, which serve more than 27,700 passengers a day, will detour using the Sodo busway to enter downtown. The city will convert a far-right lane of the Spokane Street Viaduct and the Fourth Avenue South offramp to bus-only. These buses, including routes C and 120, will not stop in Sodo but will proceed north to Third Avenue.

In afternoons, buses will leave downtown using either the Edgar Martinez Drive overpass or waterfront Alaskan Way. From there, Metro’s options include First Avenue South, or to climb the h-shaped freight Colorado Avenue South overpass next to the waterfront, then continue toward West Seattle via East Marginal Way South.

Travel schedules will average at least 10 minutes longer than normal, and riders should allow additional time for delays, Metro says.

Buses, Snohomish County

Community Transit, whose express routes move 20,000 daily passengers between Snohomish County and Seattle or Bellevue, expects I-5 delays. Bus drivers may have to start shifts early. A few buses might be added, or switched among routes.

“It’s basically dispatching on the fly,” said spokesman Martin Munguia.


Ballard, Fremont and University bridges will forbid deck openings for vessels from 7 a.m. to 10 a.m., and 3:30 p.m. to 7 p.m., seven days a week, from Jan. 11 to Feb. 9. Each of those periods ends an hour later than usual.

The lower West Seattle swing bridge, where boats normally request openings at all hours, must stay in road alignment from 7 a.m. to 10 a.m. and from 2 p.m. to 5 p.m. That afternoon period is earlier than most commutes, but studies show that’s the peak traffic time in the largely industrial area, said Mary Brown, bridge operation supervisor for the Seattle Department of Transportation. These changes apply seven days a week from Jan. 11 to Feb. 9, a Coast Guard notice to mariners says.

Street lanes

The city temporarily revoked permits to close street lanes for about 50 construction projects on center-city arterials, which may improve traffic flow. Alaskan Way was repaved this fall, to operate at its pre-2011 capacity of two lanes each direction. The city plans to continually adjust traffic signal timing, based on the congestion observed from the downtown control center.

Traffic cops

Seattle budgeted an additional $500,000 in police overtime to clear bus lanes or gridlocked intersections. Mayor Jenny Durkan has proposed camera enforcement to fine motorists who clog bus lanes, but that requires new state law and couldn’t happen before the Jan. 11 viaduct closure.

The Washington State Patrol will add two troopers to the normal 26 to 27 troopers on patrol during commute periods in King County, said Sgt. Julie Fisher.

Shuttle service

The Downtown Seattle Association’s free waterfront shuttle, funded by state Highway 99 dollars, was extended until next summer. These wheelchair-accessible blue and orange minibuses serve 14 stops, every 15 to 20 minutes, from the ferry terminal to Seattle Center, Convention Place or Pioneer Square.

To help with the viaduct closure, service to most stations will start at 6 a.m., two hours earlier than usual, and last until 8 p.m. The south route will stretch three blocks farther, connecting to transit riders at International District/Chinatown Station.

Metro has launched door-to-transit service using private Ride 2 vans around the Eastgate Park-and-Ride, and nonprofit Ride 2 Transit to the West Seattle water taxi dock and Alaska Junction buses. These are two different apps. Standard fare is $2.75, but ORCA cardholders can apply that $2.75 as a transfer, to cover a full bus trip or partial water-taxi fare.


City restrictions on construction that blocks streets should reduce how often people must zigzag and backtrack around barricades. This year 21 intersections were retimed to give pedestrians a 3- to 7-second head start before motorist signals turn green, to improve visibility and reduce crash risks.


Uber, Lyft, and ReachNow are offering discounted rides to transit hubs. And SDOT is marking more three-minute passenger-load zones, and the ride companies agreed to forbid pickups on the Third Avenue busway to help keep buses moving.


No special routes are provided. “January is not a comfortable month for biking or walking,” said Heather Marx, city downtown mobility director. “It hasn’t been a big part of our message, because it’s just a hard sell that time of the year.”

About 7,000 to 8,000 rental bikes are expected to be available by mid-January, up from 6,000 now. The Portside Trail, which goes along the waterfront from South Atlantic Street to South King Street, will remain open despite nearby road construction.


An estimated 3.3 percent of central-city employees work from home on a typical day. “I could imagine the telework rate shifting a few percentage points,” predicted Jonathan Hopkins, executive director of the nonprofit Commute Seattle.

Amazon, Expedia Group, the Gates Foundation, Holland America and the city of Seattle are among employers boosting their incentives to find alternatives to driving. If workers compressed a five-day schedule into four 10-hour shifts, that would lower commute trips 20 percent.


King County Metro operates the nation’s largest vanpool service and offers current riders a $50 incentive to recruit new riders. Kitsap Transit vans are popular to reach ferry terminals west of Puget Sound. Private matchmakers Scoop, Waze Carpool, iCarpool and Pogo appear in SDOT’s Seattle Traffic website to navigate the Highway 99 closure mess.