HIGHWAY 99 TUNNEL: Digging expected to be done in May

| Alaskan Way Viaduct | Highway 99 tunnel | West Seattle news

(WSDOT photo taken last month – work crews in the tunnel)

WSDOT says tonight that the Highway 99 tunneling machine is expected to arrive in its “disassembly pit” in May. That news comes as they also announce that Seattle Tunnel Partners has stopped digging to get the machine ready for the “final 1,000 feet of the 9,270-foot tunnel drive.” They’re checking its position because, WSDOT’s update says:

Recent surveys show that Bertha may be several inches off of the tunnel alignment. STP is conducting additional survey work and will make adjustments as needed to complete the tunnel drive.

Adjustments are common during tunneling, including on this project. STP made a similar adjustment to correct Bertha’s course after crews mined out of the pit that was used to access and repair the machine.

Crews will continue to perform routine maintenance on the machine for the next several days. They plan to resume mining next week.

According to STP’s most recent schedule, Bertha will arrive at the disassembly pit in May. The pit is located approximately 960 feet north of the cutterhead’s current location beneath Denny Way and Sixth Avenue North. Mining rates will continue to vary based on maintenance needs and soil conditions.

Crews successfully mined under the final building of the tunnel drive earlier this week. Bertha has traveled a total of 8,310 feet and built 1,270 of 1,426 concrete tunnel rings.

Because the end-of-the-line pit is part of a construction site, WSDOT has said it’s not planning to have a big event for the public to watch the machine break through.

Meantime, yet another reminder – the Alaskan Way Viaduct is scheduled to close for inspection 6 am-6 pm each day this Saturday and Sunday, with a few other events on 99 north of the Battery Street Tunnel – full details are here.

dsa March 1, 2017 (9:49 pm)

I know it’s a tunnel. I wish I knew the configuration (direction, lanes, locations) of what we are looking at in the picture.

WSB March 1, 2017 (10:10 pm)

Sorry, I don’t know. WSDOT posted it to Flickr and linked it to the WSB group, as they do with some tunnel and related photos, and while there’s more of a caption there, it doesn’t say any of that. If you have a Flickr account, you can probably try asking the question in the comment box on the page:

https://www.flickr.com/photos/wsdot/32905070035/in/pool-westseattleblog
chemist March 2, 2017 (12:59 am)

It looks like this…

dsa March 1, 2017 (10:47 pm)

That’s okay. It just looks like that flat ceiling thing, the thing with the orange supports in the background is not strong enough for traffic. I suspect that space is for air flow ventilation. The I-90 tunnel has enormous empty spaces inside them. These tunnels are round, but the driving chambers won’t be round or pie shaped, so that leaves the potential for empty spaces for other uses..

redblack March 2, 2017 (5:44 am)

i’m pretty sure that’s the upper road deck, based on this drawing:

http://www.seattletimes.com/opinion/alaskan-way-viaduct-complicated-visionary-8212-a-deep-tunnel-could-work/

redblack March 2, 2017 (5:50 am)

if the times link is broken, here’s the wikipedia drawing:

https://en.m.wikipedia.org/wiki/Alaskan_Way_Viaduct_replacement_tunnel
- dsa March 2, 2017 (10:38 am)
  
  Thanks. From that drawing, the flat surface thing I questioned about looks like a ceiling and not a driving surface.

West Seattle Hipster March 2, 2017 (7:16 am)

Where are all of the “it will never get finished” comments now?

Even though I can’t understand why the replacement to the viaduct will have less capacity in a rapidly growing region, I still think this is a helluva construction achievement.

TheKing March 2, 2017 (7:39 am)

The “where are they now’s” got taxed out of the city.
dsa March 2, 2017 (10:42 am)

I was a I don’t want a tunnel, and I was a I hope it gets permanently stalled and discarded. However I marvel at the engineering. I do wish it solved something.
- MIckymse March 2, 2017 (12:04 pm)
  
  Yes… You can also count me in don’t want it, feared it might get stuck, knew it would take much longer than they thought camp, who thinks it’s still a major and laudable achievement. That said, when we opponents claimed we didn’t need it because a surface street could manage capacity and that up to 20% of the traffic would simply “go elsewhere” everyone thought we were nuts. Yet, just take a look at the fact that close to 20% of the pre-tunnel traffic has switched to transit, taken other routes, or opted to make different choices. And now there is more traffic on an avergae day across the West Seattle Bridge then across the Viaduct.

K. Davis March 2, 2017 (9:04 am)

Given that the city isn’t taxing anyone for this project – it is a state project – your statement makes no sense, unless those folks have all moved to other less-taxed states. Or not.

Correction … the tunnel does not have “less capacity” … the current Battery St. tunnel is likewise two lanes in each direction; we’re not losing any capacity through downtown, and arguably, getting better because the tunnel will have wider, modern lanes with a shoulder and no curve that the Battery St. tunnel currently has.

MIckymse March 2, 2017 (12:08 pm)

There were previously three vehicle lanes in each direction between the stadiums and the Battery Street Tunnel, with northbound exits at Seneca and Western. When the tunnel opens there will only be two vehicle lanes through that section and NO exits in Downtown. The surface boulevard will not have any additional capacity than was there before. That is, in fact, a reduction of vehicle capacity where the Viaduct carried traffic.
- KBear March 2, 2017 (3:26 pm)
  
  There will be downtown exits/entrances at each end of the tunnel. Just because you can’t get off at Seneca doesn’t mean there are no downtown exits.
  - JVP March 3, 2017 (12:31 pm)
    
    Looking at the layout, I think there are some pros and cons to traffic flow.
    
    Pros: better connections to the south half of downtown. Even losing the Seneca exit, it looks better to me. Just get on to the surface Alaskan Way and new grid connections look efficient.
    
    Better connections to the Mercer zone with better grid connections.
    
    Better traffic flow through downtown with wider lanes, no tight curves, and none of that crazy merge entrance right before the Battery St. tunnel.
    
    Con: worse connections from W Seattle to Belltown area with the loss of the Western Street exit.
    
    I think it’s a slight net gain for traffic flow, with Belltown commuters paying the price.
    
    I’ve been a big fan of the tunnel from day one, even with the problems. It’s the right long-term decision, though painful in the short-term. Tunnels are a very seismically stable, and can last for hundreds of years. Bridges, not so much.
Chemist March 2, 2017 (2:17 pm)

“Local” and “Port of Seattle” makes up about 10% of the funding and the Port is using their local levy authority to make that contribution from property taxes.

http://www.wsdot.wa.gov/Projects/Viaduct/Budget
- AMD March 2, 2017 (3:14 pm)
  
  Port of Seattle isn’t a city of Seattle tax. “Local” taxes aren’t city-specific either. I don’t think anyone’s debating that folks in Seattle are paying for the tunnel. Everyone in Washington State is paying for the tunnel to some extent.
  
  The idea that someone was taxed out of Seattle just because of the tunnel is a little absurd. The Port is by far the bigger of the taxes you named and even that is a pretty small amount per household.
  
  http://www.wsdot.wa.gov/NR/rdonlyres/A0086739-79D7-4ABD-A01B-DA39AA32D710/0/BoredTunnel_CostFunding_folio_May09.pdf
DarkHawke March 2, 2017 (5:23 pm)

The loss of capacity is due to the tunnel not being able to accommodate the heavy trucks that the Viaduct can, most of them carrying freight from the docks. THAT is the traffic that will shunt over to surface streets and I-5, thus increasing traffic woes, not alleviating them.
- Question Authority March 2, 2017 (7:54 pm)
  
  That’s funny because I see two semi’s in the attached pictorial of the tunnel traffic, what will be banned will be hazardous cargo not trucks per se.

wetone March 2, 2017 (5:53 pm)

What’s a toll ? a usage tax and how much will it be ? $2-3 dollars each way ? As others have said neat project but solves and improves nothing. Toll fee’s will burden many people, pushing much more traffic onto surface streets creating more issues for all. Hopefully city gets their little book done on how and what to do when there’s on accident ; ) probably have to build special equipment and tow trucks costing tax payers millions. Sure don’t want to be in there if there is a problem.