Alaskan Way Viaduct Replacement Update – June 2013

TBM assemblyMilepost 31 Speaker Series – Operating the SR 99 tunneling machine

Bertha, the world’s largest tunneling machine, is currently being assembled in the SR 99 tunnel launch pit near Seattle’s stadiums. Join WSDOT for this month’s speaker series to find out next steps as crews test the machine and prepare to begin tunneling. You’ll also learn about some of the technological advances on the SR 99 tunneling machine, including how a 300-foot-long machine steers underground and what happens when the massive steel cutters on the front of the machine need to be changed.

6 to 7 p.m.

Thursday, June 6

Milepost 31

211 First Ave. S., Seattle

Admission is free.

After the talk, be sure to leave enough time to explore the rest of the First Thursday Art Walk in Pioneer Square. Milepost 31 is open Tuesdays through Saturdays from 11 a.m. to 5 p.m., and stays open until 8 p.m. on First Thursdays.  Free parking is available for First Thursday art walk patrons in Pioneer Square. Please visit for more information about participating garages.

And don’t forget you can track Bertha’s journey to Seattle on Twitter by following @BerthaDigsSR99.