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Bertha reaches finish line of Seattle tunnel

SEATTLE — On Tuesday morning, the moment finally came.

With tumbling concrete and a choking cloud of dust, the tunnel machine Bertha broke through to daylight, completing a 1.7-mile drive from Seattle's Pioneer Square to South Lake Union, marred by an epic two-year breakdown.

"This is success. The dust represents breakthrough," said Joe Hedges, project administrator for the Washington State Department of Transportation.

The machine spent less than four hours grinding through a five foot wall, into what will become the north portal of the tunnel, which is projected to open in 2019.

"The only thing stronger I've seen is King Kong and now we've got ourselves a tunnel," said Washington Governor Jay Inslee, who witnessed the breakthrough.

With the project three years behind schedule, Bertha had become a punch line in Seattle.

But the last eleven months of drilling have gone well, a major achievement for the world's largest diameter tunnel machine.

The mood among project workers was electric.

"I'm sure the pyramids had problems during construction but nobody remembers that, they just remember a wonder of the world, and that's what you have here, a wonder of the world, a five-story tall tunnel," said Hedges of WSDOT.

The global tunneling industry has been watching Bertha.

For the first time since the breakdown, Takashi Hayato, the U.S. president of Bertha's manufacturer,

"We're so proud to supply the machine itself and this is just a moment to prove our machine fully completed and performed very well," Hayato said.

Bertha set out to dig a tunnel more than four years ago to replace the Alaskan Way Viaduct after issues were exposed by the 2001 Nisqually earthquake. It notoriously broke down and sat under the city of Seattle during repairs for two years in the early stages of the state Route 99 tunnel project.

The machine broke through a concrete wall at Sixth and Thomas streets near the Space Needle around 11:30 a.m., ending its 1.7-mile drive.

When the cutterhead emerged, work stopped temporarily to clean up the cement that crashed down. Bertha will now be move into a receiving pit, where it will be broken down into smaller pieces and carried away. The process of disassembling the machine will take four to five months.

But a post-Bertha Seattle doesn’t mean the job is finished for the tunnel project. There is more than a year’s worth of work left in its 9,270-foot-long wake.

>> Related: Bertha timeline: From conception to tunnel completion

Contractors estimate the tunnel will open to traffic in 2019; three years late.

According to Washington State Department of Transportation’s contract with Seattle Tunneling Partners (STP), the four-lane toll tunnel was originally supposed to open to traffic at the end of 2015.

>> Related: Bertha tunnel under downtown Seattle: See a 360-degree view

The project has encountered major problems.

  • The machine’s cutting teeth struck a 119-foot pipe, 8 inches in diameter, on Dec. 3, 2013, according to a contractor. But WSDOT disagreed with the assertion that the pipe caused the damage, and the issue is being litigated. The machine overheated and came to a halt three days later.
  • It remained mostly inactive for more than two years as crews tried to fix the problem.
  • In January 2016, Gov. Jay Inslee ordered that the drill stop after a sinkhole formed behind the troubled machine.

Project leaders have warned that total overruns might grow as high as $149 million by the time the project is done.

KIRO 7's Graham Johnson learned just how much money could be at stake: Court filings show contractors have filed a $480 million claim with the state to cover the cost of repairing and reinforcing Bertha.