Dec. 16 project update: Get ready for the year of the north portal

Posted on Dec 16 2016 3:46 PM

As we get set to flip the calendar, there’s no doubt about it: 2017 will be a big year at the north portal.

Yes, Bertha is scheduled to arrive here in June 2017, but there’s much to look forward to before that day comes. In fact, some important changes could take place before the start of the new year.

Several new street connections are set to open soon near the future north portal operations building. The opening of these new roadways, as well as additional sidewalks in the area, will increase mobility and create new connections to nearby city streets.

The extension of Sixth Avenue North between Harrison and Mercer streets is slated to open in late December. Harrison Street, between Taylor Avenue North and SR 99/Aurora Avenue North, will open shortly after. Only right turns will be permitted to and from southbound SR 99 at Harrison Street. Details are shown in the map below.  

These new connections are among the final steps in our North Access Project, which built new roadway connections to the future tunnel. Contractor Atkinson Construction will be wrapping up work over the next few weeks.

Traffic changes map for 6th Ave at the north portal

This map shows traffic changes that will be happening soon near the tunnel's north portal.

A polished look
Much of the permanent landscaping at the north portal has been installed. That includes the “signature tree” that crews planted earlier this year. Additionally, Seattle Tunnel Partners crews are building a new plaza outside the north portal operations building. Read more about the plaza in our new Program Spotlight.
Getting ready for Bertha
Bertha has approximately 2,600 feet to go in her tunneling journey. She’ll reach daylight here, in a large pit just north of Thomas Street, near the operations building. STP will then shift its focus to removing the massive machine in pieces from the pit as they continue building the double-deck highway inside the tunnel.
New connections
Today, John, Thomas and Harrison streets are divided by traffic traveling on Aurora Avenue North. When the viaduct program is complete, these streets will connect across Aurora. This change is possible because SR 99 traffic will enter the new tunnel further north than it does in the current highway configuration. The Harrison Street connection across Aurora will open when the tunnel does; John and Thomas streets will be reconnected by a future contractor. Increasing the number of east-west connections will improve mobility in the neighborhood.
Street connections at the north porta

This map shows the reconnected street grid near the north portal at the end of the program.