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Bertha finishes digging the Alaskan Way Viaduct replacement tunnel

The tunnel boring machine has emerged into the daylight

The tunnel boring machine’s disassembly pit near Seattle Center before the breakthrough
WSDOT/Flickr

Bertha, the tunnel boring machine digging the State Route 99 tunnel, which will eventually replace the Alaskan Way Viaduct, has finally emerged from underground after nearly four years and 9,270 feet.

Bertha’s cutterhead slowly spins at the entrance of the disassembly pit.
WSDOT

Now that the machine has broken through, it will spend the next few weeks getting into position for disassembly.

While a drill peeking out of the ground may not seem that exciting out of context, in Bertha’s case, it’s a momentous occasion. After a two-year delay between 2013 and 2015, many got used to Bertha being underground forever.

The machine’s immobility even made national news—our favorite was when Bloomberg published a longform feature complete with adorable, rock-chomping GIF of the machine.

Bertha’s slow progress has, naturally, done little to quell concerns about the project itself. The tunnel’s critics predicted early on that the machine could get stuck underground, and they’ve had little comfort for longer-term concerns about the project, like rising cost overruns.

The pit continues to be live streamed on WSDOT’s website.

Meanwhile, as Bertha moves forward, crews are building two decks of highway behind it. The double-decker highway has been under construction in the wake of the machine since 2016.

WDOT estimates the tunnel should be ready for traffic in 2019.