Alaskan Way viaduct

clerk.seattle.gov

Settling ground is affecting the Alaskan Way viaduct, Pioneer Square buildings and underground water pipes, Seattle utilities officials said Monday. Engineers think the sinking is connected to the Highway 99 tunnel project, but it probably has little to do with actual digging.

Elaine Thompson / AP Photo

The safety of the Alaskan Way viaduct will be back on the table Monday when the Seattle City Council will hear from the Washington State Department of Transportation about planning for a short- or long-term closure of the busy highway that runs along Seattle's waterfront. 

Seattle Tunnel Partners

Officials overseeing the replacement of Seattle’s Alaskan Way viaduct are trying to tamp down safety concerns. But under questioning Monday from Seattle City Council members, they had a hard time coming up with an answer for when people should start to worry.

Peterson and Brothers / Museum of History and Industry, Seattle

The plan to dig a shaft 12 stories deep to fix Bertha, the Seattle tunnel boring machine, has been put on hold while archaeologists make sure crews won’t dig through important historical sites. 

On Thursday, workers started boring approximately 60 holes, each about as wide as a grapefruit, and digging as deep as 40 feet down through layers of Seattle's floor, which, at the moment, is also Bertha's ceiling. 

WSDOT

State highway engineers will shut down a stretch of the Alaskan Way viaduct later this month to take a closer look at cracks found on the roadway.

What workers found during a routine inspection of the viaduct on March 1 isn’t that unusual, says Tom Baker, an engineer with the Washington state Department of Transportation.

WSDOT

The Washington state Transportation Department says that, as expected, the contractors digging a highway tunnel under downtown Seattle will repair a seal system on the tunneling machine by digging a shaft in front of it.

WSDOT

The prospect of taking the State Route 99 tunneling machine known as Bertha offline for as much as half a year is not good news for the company operating it. But one Seattle tunneling expert says it could be worse.

“It’s really a problem with the machine itself. I think it’s something that can be repaired,” said the University of Washington’s Joseph Wartman. “And I think in a couple of years when the tunnel is open, people will have forgotten about this.”

Seattle Tunnel Partners

Washington transportation officials and the private contractor operating the tunneling machine known as Bertha disagree on what’s holding up progress on the Highway 99 tunnel project. Neither had definitive answers, but appearing together Tuesday at a news conference, it became clear they’re leaning toward conflicting theories.

WSDOT

The state contractor hasn’t yet decided how to fix the broken seal near Bertha’s bearing, but “either way, this process will take months,” said the state Department of Transportation late Monday.

WSDOT

Remember that big steel pipe — eight inches wide, part of an old well?

The Washington State Department of Transportation never actually accused that pipe of blocking Bertha, but it was definitely a prime suspect.

But on Friday, WSDOT said the pipe isn’t, and never was, the problem.

WSDOT

Seattle's massive tunneling operation is on hold yet again due to ongoing problems with the world's largest boring machine.

After a seven-week stoppage, crews restarted the tunneling machine earlier this week and moved it forward about two feet. Washington state's Department of Transportation said Friday that the machinery showed above-normal temperature readings when that movement occurred.

WSDOT

A Washington Transportation Department spokeswoman says the giant machine digging a highway tunnel under downtown Seattle has advanced two more feet, far enough to allow crews to build the next concrete ring of the tunnel.

Tuesday's progress was the first for the machine in nearly two months, since it stalled Dec. 6 some 60 feet underground.

Senator: Seattle Should Pay For Tunnel Cost Overruns

Jan 9, 2014
WSDOT

A leading Republican in the state Senate says Seattle taxpayers should foot the bill for any potential cost overruns on the Alaskan Way Viaduct replacement project.

The machine digging a tunnel to replace the elevated highway along Seattle's waterfront has been stuck for more than a month, raising concerns that more funds will be needed for that $1.4 billion project.

What if Seattle gets stuck with cost overruns on the Alaskan Way Viaduct replacement project?

That question sparked a lively exchange on KING-TV between the two candidates for mayor of Seattle during their first televised debate.

During the hour long debate sponsored by KING-TV, KIRO-FM and The Seattle Times, Mayor Mike McGinn and Sen. Ed Murray traded jabs on everything from leadership style to police reform.

But their discussion of the tunnel project raised one of the most interesting questions.

WSDOT

The drill known as Bertha is back to eating dirt after a slow start, then a delay, then a delay caused by the delay.

The massive machine boring the Highway 99 tunnel beneath Seattle had been sitting still while two labor unions duked it out over a handful of jobs.

Gov. Jay Inslee announced last week he’d brokered a deal in the dispute, and said the digging would resume after a few days.

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