Seattle SR-99 Tunnel: construction difficulties

The Alaskan Way Viaduct replacement tunnel, also known as the SR 99 Tunnel, is a bored highway tunnel in the city of Seattle.. The 2-mile (3.2 km), double-decker tunnel carries a section of State Route 99 under Downtown Seattle.

Construction began in July 2013 using "Bertha", at the time the world's largest-diameter tunnel boring machine. After several delays, tunnel boring was completed in April 2017, and the tunnel opened to traffic on February 4, 2019.


I find it ironic that in the 21st century it took us 5 years to complete, and 7 years to launch a 2 mile (3.2 km) tunnel. This construction time is comparable to that of:
  • Box (2.95 km, 1838-1841) - straight, and descends on a 1 in 100 gradient from its eastern end.
  • Mersey (1.2 km, 1881-1886) - Oldest and first longest underwater rail tunnels in the world, Crossing the Mersey in Liverpool
  • Severn (7.01 km, 1873-1886) - One of the oldest underwater tunnels in the world
The below two facts (pertaining to two major construction halts) could be even more ironic:
  1. Three days prior to stopping (in 2013), the machine mined through an 8-inch-steel well-casing used to help measure groundwater in 2002 around Alaskan Way, drilled as part of the planning phases of the project. Whether this pipe had anything to do with the machine's failure is at the center of legal dispute between WSDOT and the contractor, Seattle Tunnel Partners. This delay lasted for more than two years as the workers had to dig a 120-foot (37 m) vertical shaft down to Bertha's cutting head to repair it. Settling was discovered in Pioneer Square that may be related to this additional excavation.
  2. Tunnel boring had resumed on December 22, 2015. The tunnel boring was halted 23 days later on January 14, 2016, after a 30-foot-wide (9.1 m) sinkhole developed on the ground in front of the machine, causing Governor Jay Inslee to halt drilling until the contractors can perform a root cause analysis to show that the machine can be run safely. Even though contractors filled the hole with 250 cubic yards (190 m3) of material, the ground above the tunnel-boring machine continued to sink, according to the Washington State Department of Transportation.
We all can speculate on what those sinkholes could mean in a city like Seattle.


Additionally that 8 inch steel pipe mysteriously disappeared:

KD: Curious if this Seattle Tunnel saga had anything to do with possible buried buildings they had to drill through.

Funny that Brunel's 1843 tunnel looked so much cooler when completed. Sure enough it allegedly took him 18 years to build it, but he started in 1825, and built it under the Thames River.

1843_brunel Tunnel.jpg

I think it is down near the train station - China Town - nowadays known as "The International District". Jackson St crosses it. This has always been my impression.
Well, it appears to be a hill. That would suggests it goes West to East. I do not remember seeing any similar South to North grade like this in the vicinity. Could 4th Avenue have this grade? It appears that 4th and Jackson is just about the only place with an opening down below the street level.


But then we have two towers sticking out from behind the buildings. Do those look like the ones we have at 18th and Madison?
That photo does appear to be from the 60s/70s. Things change. I know the Chinatown neighborhood pretty well. It is close to the Pioneer Sq 1889 fire area. 4th St runs north from the train station with an slight uphill grade.

I'm not as familiar with 18th and Madison. But looking again, it could be South Capital Hill. Maybe back in the day, a train ran to Madison Park on that road/route?
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Mr. Zobrist worked at Seattle City Light-- that is right near the Chinatown possibility.
Mmm.. There is a steep grade to the bay. There has been a tremendous amount of building in that area over past 50-60 years. I can't really say. It is pretty fancy nowadays.
Maybe try and find an old phone book at a library? Then you could attempt to look up the electronics store and New Seattle Music store?
Good luck!

Pretty amazing that our roads could be constructed on the roofs of old buildings. I'd also say it's amazing that you could dig up something like that in the 60s or 70s and no one batted an eye, but even today they still dig up stuff around my area which seems to show an severely aged infrastructure underneath and most people don't give a rip. Too busy participating in the "rat race."
Did you ever hear any more rumors about the cause of "Birtha's" sudden stop?
Nope. But I will see if the tunnel and our brick buildings share the space. I'd imagine what we see on the OP photograph is just a tip of the iceberg. Having 2 or 3 stories underneath the street level with noone knowing about it... that's incredible.
I’m gonna try to merge this with the SR-99 tunnel thread. Both cover the same issue. Did some extra map-snooping, and I’m pretty positive the west side of the 1212 1st Av is the place.
  • Merging was successful

I think this is where they built the Alaskan Way Viaduct.


End of Seneca Street before completion of ramp to Alaskan Way Viaduct, Seattle, June 30, 1961

I think the narrator of the above video is totally wrong about the time frame, the location (after verifying) is correct to a degree. The building under the road does not appear to have anything to do with this hotel at 1216 1st Avenue.
  • Now the hotel is simply known as "The Diller". It has been turned into apartments used by many students and artists today though it is still legally considered a hotel. It has become known for The Diller Room, a nostalgic-style cocktail bar was created by Robert B. and Josie S. Wilson in 2009. It occupies part of the former lobby and what was once The Diller Bar and The Flamingo Room post WW2 through the 1970s. The area has improved and is fast becoming one of the best parts of the city being home to major attractions such as the Pike Place Market and the Seattle Art Museum as well as top hotels such as the new Four Seasons, Hotel 1000 and the Harbor Steps on First Avenue.
  • n 2017, the block surrounding the Diller Building was demolished for the development of 2&U, a 38-story high-rise office building.
  • The Diller Hotel
Some dude in there says this:
  • Seattle raised it's street level near the waterfront at some point to deal with tides.
Sure, those people were dumb and stupid to build their railroad system right where it would constantly gets flooded.
  • They even built a railway tunnel because they were so stupid and had no idea what they were doing.
  • Source
"Debunking mudflood" channels? Of course there are. What joyous people those must be!

I mean, I'm all about rational skepticism, but I have a inkling that's not what's going on there.
Why bother with the crap video?

The exterior of the building in the op image and the wiki waki image linked is the same. The only other building I have seen with similar terracotta work is the one behind that god awful sinking ship car park.
If one of Herbs stores was on the same street as the Diller then you have your location confirmed.

Is Herbs store building the one with the circular red sign on it?

Screenshot 2021-07-10 at 20-51-53 Seattle_-_Diller_Hotel_Building_02 jpg (JPEG Image, 4288 × 2...jpg

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