On the 12.03.2016 the SR99 TBM Bertha reached its last maintenance stop. Seattle Tunnel Partners (STP) will take up to one month to inspect the TBM and provide any maintenance that is needed. Some scheduled work is involved and will include performing hyperbaric interventions, inspecting the cutterhead and the main drive unit and the screw conveyor. There will be replacement of cutting tools as well as extending the conveyor belt and the high-voltage cable.

WSDOT plans to close the Alaskan Way Viaduct for approximately two weeks to allow the machine to pass beneath the structure. Seattle Tunnel Partners (STP) has now mined a total of 475.49 m. Click here and us/69 for the tunnelbuilder archive. Visit http://www.wsdot.wa.gov/. 13/16.