(This afternoon’s view from construction-site camera looking south over northbound tunnel entrance)

As the planned Alaskan Way Viaduct closure gets ever closer – we’re now 2 1/2 months from January 11th – WSDOT has announced another tunnel project milestone:

Close followers of the project know that our website is home to an archive of contractor Seattle Tunnel Partners’ monthly schedule updates. These updates don’t show all the construction that’s happening on the project, but they do give an indication of critical work activities that must be completed to achieve an important contract milestone – “substantial completion” of the tunnel.

STP reached substantial completion earlier this month. This is the first of three contract milestones in STP’s work on the tunnel. It means the tunnel is far enough along for STP to officially hand the facility over to WSDOT. It doesn’t mean STP’s work is done, but it does mean the tunnel could be technically operated as designed.

What comes next is a variety of wrap-up work elements that, once completed, will result in the tunnel reaching the second milestone, known as “physical completion.” Meanwhile, as STP works toward physical completion, WSDOT will continue to train maintenance and operations staff to ensure the tunnel and those responsible for its operation are ready to go in early 2019.

The final contract milestone, aptly named “final completion,” will be achieved when paperwork and documentation are done. The tunnel will open before this final milestone is reached. You can see the latest schedule update – along with those from previous months – on our schedule page.

P.S. Got questions about the upcoming viaduct-to-tunnel transition? Your next chance to ask them is this Thursday night, when WSDOT reps are among the guests at the North Highline Unincorporated Area Council meeting in White Center (7 pm Nov. 1st, 1243 SW 112th).