VIDEO: WSDOT says Highway 99 tunneling machine has taken its ‘next step’

The Highway 99 tunneling machine is out of sight but by no means out of mind.

WSDOT announced this morning that the machine has started moving forward in the “access pit” where its cutterhead was accessed for repairs (now backfilled, as shown in the WSDOT time-lapse video above). Here’s the full text of its latest news release (and note the reminder of a Viaduct closure in a few months, if all stays on the current schedule):

The State Route 99 tunneling machine entered its next phase of testing early Tuesday, Dec. 22, near Pier 48, moving forward and installing a tunnel ring at the bottom of the 120-foot-deep pit crews built to access and repair the machine. Seattle Tunnel Partners, the Washington State Department of Transportation’s design-build contractor for the tunnel project, plans to tunnel a short distance further in the access pit tunnel before giving crews a break for the holidays.

“Testing the machine in the conditions it will face during the rest of the tunnel drive is a critical part of our work to resume full-production mining,” said Chris Dixon, Seattle Tunnel Partners project manager. “The next several hundred feet of excavation will give us the information we need to make final adjustments before we tunnel beneath the viaduct and downtown.”

After the new year, STP plans to mine out of the access pit toward a planned maintenance stop 450 feet to the north. Along the way crews will mine slowly while installing tunnel rings and continuing to run tests. When the machine reaches the maintenance stop – essentially an underground block of concrete just south of Colman Dock – crews will perform maintenance and make final adjustments before diving beneath the viaduct.

Tunneling under the viaduct will require a full closure of SR 99 through downtown for approximately two weeks. The contractor’s latest projections show that the closure will occur in March, but the actual closure date will depend on Bertha’s progress and the state cannot verify the contractor’s schedule.

STP and Bertha’s manufacturer, Hitachi Zosen, are responsible for the repair effort, including the schedule. While the machine was under repair, STP continued essential work at the future tunnel portals, including construction of ramp and highway connections, and the buildings that will house tunnel operations.

STP crews halted tunneling in December 2013 after the machine overheated. After an investigation, they discovered damage to the seal system and determined it needed to be replaced along with the main bearing. The cause of the damage has not been determined. Responsibility for costs associated with the delay will be determined through the process outlined in the tunnel contract.

“Moving the tunneling machine forward in the access pit is the next step in STP’s testing program,” said Todd Trepanier, WSDOT’s administrator for the viaduct program. “WSDOT will continue to protect taxpayers as we work with STP to complete the project.”

Pibal December 22, 2015 (11:57 am)

If the schedule holds, we should all plan an extended Spring Break in March. Two weeks without 99. Ouch!

cjboffoli December 22, 2015 (12:46 pm)

Pibal: That’s two weeks if all goes well. It might get really interesting if that crumbling, 1940’s designed, earthquake damaged relic of a viaduct decides not to play along. And there’s the added wild card of the waterfront’s mystery grab bag of soil quality.

John December 22, 2015 (1:08 pm)

Won’t have any affect on my bike ride into town…. As long as WSDOT continues to provide bikers with paved detours like they have been. The current end of the bike trail goes under the south end of the Viaduct. WSDOT will need to send us bikers somewhere else.

any wagers? December 22, 2015 (1:36 pm)

should we begin a friendly wagering exercise to guess the date for the next time Bertha breaks down? I also think the waterfront fill will present some interesting relics to bore through.

Joe Szilagyi December 22, 2015 (2:22 pm)

I wonder what a public records request hunting for “maximum cost before the project is a failure” type things would turn up.

Born on Alki59 December 22, 2015 (4:25 pm)

No wagers here. Lucky if it makes it the 450′ without another major fubar.

wetone December 22, 2015 (6:52 pm)

Funny how that crumbling 1940′s designed, earthquake damaged relic of a viaduct has held up considering it has already sank 2x the original spec WSDOT gave the public at start of project. I wonder if SDOT has a hard number for that now ? Between Bertha and waterfront rebuild shaking and vibrating soil, viaduct has held together better than a lot of buildings in same area. The old girl must not have been in as bad shape as they lead everyone to believe as it’s still in use ;) As far as “wild card of the waterfront’s mystery grab bag of soil quality” They have known that from the start. All one had to do is look at Seattle’s history and old pictures. Anybody with commonsense could see the issues. No rocket scientist needed. This project from start had very little to do with the safety of viaduct. $200mil it could of been retrofitted and been good for another 75yrs. Giving people a nice view sitting in traffic and leaving billions $$ to fix infrastructure that’s really falling apart. Now we will have a tunnel with tolls, debt, less capacity, no growth options, putting more pressure and traffic on surface streets. win win

chemist December 22, 2015 (7:06 pm)

I’ll bookmark that comment John. It will be a nice template for when they do some proactive maintenance on the lower bridge and decide to leave it raised for 2 weeks while working on it.

kobdvs December 22, 2015 (7:27 pm)

@wetone … and your PhD in civil/structural engineering and soil mechanics is from what institution of higher learning?

dsa December 22, 2015 (11:17 pm)

The problem is the tunnel route was not selected by civil engineers, but by politicians. It would be nice if politicians could at least count. There are currently six lanes through downtown and no toll. Later there will be four lanes and a toll. It makes no sense.

Biff Hadley December 22, 2015 (11:35 pm)

So will they be closing the City down when this thing tunnels under it?

Wb December 22, 2015 (11:55 pm)

You don’t need a degree in any subject to see that this was the worst solution for the waterfront and for the people of this city. It’s hilarious how people stoop to ridiculing the viaduct when it has been standing and working this whole time. Go drive it. See if it crumbles under your tires.

John December 23, 2015 (8:13 am)

@chemist… I will admit that’s a good comeback. :-)

In that case I’ll take the passenger ferry across or simply ride an additional 4 miles and take the 1st Ave bridge. No problem.

wetone December 23, 2015 (9:28 am)

kobdvs, you ask where I learned my civil/structural engineering and soil mechanics.
Building sandcastle’s and caves at Alki as a kid. That’s all I needed. The good old days when city kids would learn commonsense from real life experiences ;)

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