May 26 project update: Bertha reaches Western Avenue

Posted on May 26 2016 2:41 PM
Seattle Tunnel Partners crews have successfully tunneled beneath the Columbia Street on-ramp to the Alaskan Way Viaduct. Bertha, the SR 99 tunneling machine, passed approximately 50 feet below the structure’s foundations and is now beneath Western Avenue, heading toward Marion Street. The on-ramp, like the viaduct, remains stable.
 
As of May 26, Bertha had traveled a total of 2,255 feet. She is in zone 3 of the tunnel drive. The top of the tunneling machine is now more than 100 feet below the surface. 
 
Look for another progress update on Tuesday, May 31, following the holiday weekend.  
 

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