Inside Bertha, the SR 99 tunneling machine, a giant network of wires, pipes and hoses supply the machine with air, water, electricity and other materials. Look closely at the top left of this October 2016 photo and you’ll see the number 721. The number marks the 721st concrete ring of the SR 99 tunnel. By the time tunneling is complete, Bertha and her crew will have built 1426 of the rings that form the circular outer wall of the SR 99 tunnel.

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Inside Bertha, the SR 99 tunneling machine, a giant network of wires, pipes and hoses supply the machine with air, water, electricity and other materials. Look closely at the top left of this October 2016 photo and you’ll see the number 721. The number marks the 721st concrete ring of the SR 99 tunnel. By the time tunneling is complete, Bertha and her crew will have built 1426 of the rings that form the circular outer wall of the SR 99 tunnel. Learn more about the Alaskan Way Viaduct Replacement Program at ( ) or follow Bertha, the SR 99 tunneling machine, on Twitter @BerthaDigsSR99 ( ) . Bertha’s trailing gantries 29827700474 o

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Size: 1935px × 1291px
Photo credit: © PR images / Alamy / Afripics
License: Licensed
Model Released: No

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