Launched in late August 2016 when Bertha passed beneath First Avenue and Union Street, #BalloonsOverBertha is yet another way to track progress on the SR 99 Tunnel Project.

The idea is to provide a visual of Bertha’s location relative to the surface. At the intersection of Second Avenue and Lenora Street, Bertha's cutterhead and the surface was about 200 feet.

Learn more about the Alaskan Way Viaduct Replacement Program at www.alaskanwayviaduct.org or follow Bertha, the SR 99 tunneling machine, on Twitter @BerthaDigsSR99.

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Make:	NIKON CORPORATION
Model:	NIKON D800
Exposure:	0.006 sec (1/160)
Aperture:	f/4.5
ISO Speed:	320
Focal Length:	32 mm
Lens:	18.0-35.0 mm f/3.5-4.5