Giant tunnel-drill machine Bertha broke into daylight shortly before 11:30 a.m. Tuesday after years of delays. We covered the scene live.

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What’s happening:

[This live feed is no longer receiving updates. For a full story on Tuesday’s milestone, look here.]

Bertha breaks through


Update, 12:33 p.m.:

Bertha has emerged and its cutterhead has stopped spinning. Here’s a hypnotic GIF in case you missed it.


Update, 11:50 a.m.:

Tuesday’s Bertha excitement may soon be over.

Concrete pieces from the upper portion of the machine’s break-through point are falling, which means crews may soon have to pause.


Update, 11:26 a.m.:

Bertha has broken into daylight.

After a dig that’s spanned years, a part of the massive tunnel-boring machine has cut past a concrete wall.

Seattle Times reporter Mike Lindblom, who’s at the construction site, said he can see the machine’s cutting wheel on the east side of the pit as Bertha strips away concrete.

The bottom end of the machine’s cutting head is breaking through first, while the top remains in tact.

Large concrete chunks have fallen and fluid continues pouring into the construction pit.


Update, 11:05 a.m.:

Lindblom said crews have urged reporters to retreat behind a temporary wall because of dust.

He said he hears occasional cracking and popping sounds with the machine’s churning, but “there’s no visible large breakdown of the wall yet.”

To help clear the dust, sprinklers are set up over the machine’s break-through point.

Highway 99 program Administrator Joe Hedges just spoke with the reporters, saying Bertha is right on target.

“I’m celebrating. I’m jumping up and down,” he said.

Hedges said crews are steering the massive machine upward by about 2 inches, so that it can eventually rest and slide easily on a steel cradle after it breaks through.

He said the machine has been moving at approximately 7 millimeters per minute Tuesday, a rate that’s similar to predictions.


Update, 10:25 a.m.:

After a roughly five-minute pause, Bertha is grinding again.

A mix of water and soil conditioner has filled the construction pit.

Executives of Hitachi Zosen, the Japanese firm that designed and built the machine, will be at the site Tuesday to “celebrate this historic milestone,” the firm said in a news release.

The firm is “pleased and proud” that Bertha is completing its dig for the Highway 99 tunnel project, Hitachi Zosen U.S. President Takashi Hayato said in the release.

“Throughout the tunneling process, Hitachi Zosen fully committed itself to the successful completion of the project, even when difficulties were encountered early in the tunnel drive,” Hayato said. “We are excited that the people of Washington state will enjoy the benefits of the deep bore tunnel and the eventual removal of the elevated viaduct.”


Update, 10 a.m.:

Dust is filling the construction zone as the huge machine nears the surface.

This won’t be the first time Bertha has emerged into daylight.

Back in 2015, the machine broke through the wall of a repair pit dug to fix the stalled machine. Watch that dusty arrival here to get a taste of what we might see later: