After a week of clogged and congested highways and city streets, commuters are back on the State Route 99 Alaskan Way Viaduct this morning, albeit traveling at a slower construction speed and navigating curves that will take some getting used to.

The Washington State Department of Transportation reopened all lanes of the viaduct at 12:44 p.m. Saturday after more than a week of demolition and construction.

Slower speed limits are posted on the SR 99 viaduct and on a new construction bypass, and as drivers adjust they could see delays of about 10 minutes during busy peak travel times through downtown. Much of the viaduct is now posted at 40 mph from the Battery Street Tunnel to the West Seattle Bridge, and a 25 mph recommended speed limit is in effect through a new curving construction bypass near the sports stadiums. Even though speeds will likely be slower on SR 99 for the next few years, the bypass roadway allows this critical corridor to remain open until the new SR 99 tunnel is completed at the end of 2015.

“Drivers should be ready to slow down through the new construction bypass and pay careful attention to all of the changes on the new SR 99,” said Matt Preedy, WSDOT Alaskan Way Viaduct replacement program deputy administrator. “Drivers likely will be distracted as they look at Seattle’s changed landscape without the southern end of the viaduct, and it will take time to get used to the curving route near the stadiums.”

WSDOT also opened a new southbound SR 99 off-ramp to SODO last night at South Atlantic Street, replacing the previous southbound exit to South Royal Brougham Way. This exit will now be a key route to the stadiums.

The changes come after an intense week of demolition and construction. Crews demolished 2,825 feet of the seismically vulnerable southern mile of the viaduct, turning it into thousands of tons of concrete rubble and steel rebar. Crews also completed the new construction bypass, which sets the stage for construction of a new SR 99 tunnel to replace the viaduct through the downtown core. Drivers will use the construction bypass until the tunnel is open to traffic at the end of 2015.

Viaduct closure by the numbers

- 2,825 feet of demolished viaduct
- 125 construction workers on the job daily
- 30 munchers, crunchers and excavators for demolition work
- 3,500 estimated truckloads of concrete rubble to be recycled and used for construction surfaces for the tunnel project
- 2,500 estimated truckloads of steel rebar to be recycled
- 3,000 feet of concrete traffic safety barrier installed
- Closing the SR 99 viaduct Oct. 21 forced 110,000 daily drivers to find another way to get to and from Seattle using alternate routes, times or ways to commute. Some took advantage of additional bus trips, water taxi sailings and bike routes. Travel times doubled during some of the worst evening commutes last week as vehicles shifted to Interstates 5 and 405, but it could have been much worse.

In preparation for five years of south-end viaduct construction, WSDOT invested $125 million in roadway improvements, transit service and real-time driver information signs on key commute routes. WSDOT worked for several months on advance coordination with transit, the port and city on strategies to keep commuters and commerce flowing during the SR 99 closure.

The week of work was part of the $114.6 million contract WSDOT awarded to Skanska USA Civil for the SR 99 Holgate to King Project to rebuild just the south end of SR 99 as it leads up to the future tunnel portal. The overall Alaskan Way Viaduct Replacement is $3.1 billion and includes a $1.35 billion contract to Seattle Tunnel Partners to build a new SR 99 tunnel.

Next steps

In coming months, crews will begin driving support piles for a second bridge through SODO that will eventually carry three lanes of northbound traffic. Later this year, Seattle Tunnel Partners will demolish an additional section of the old SR 99 viaduct south of South King Street near the new construction bypass, a move that allows the contractor to prepare a construction zone for the SR 99 tunnel. More details about the Alaskan Way Viaduct projects are online at http://www.wsdot.wa.gov/projects/viaduct.

SR 99 construction bypass details

A slower, 40 mph speed limit is in effect on much of the viaduct between the Battery Street Tunnel and the West Seattle Bridge.
A 25 mph recommended construction zone speed limit is posted through the curving bypass in the SODO area. A map shows the construction bypass and where it connects to city streets. A video shows what driving the bypass looks like.
Metro Transit’s 11 bus routes that travel on SR 99 will began using the new bypass at the start of service on Sunday morning, Oct. 30.