Bertha surges 6.5 feet ahead as crews prepare to tunnel out of pit
Jan 5, 2016, 9:07 AM | Updated: 9:47 am
The Seattle tunneling machine Bertha moved 6.5 feet forward on Monday.
Bertha, Seattle’s tunneling machine, is inching closer to its goal.
Bertha tunneled 6.5 feet on Monday, putting its cutterhead close to the concrete wall at the end of the repair pit.
The machine is expected to punch through the 15-foot-think wall “in the coming days,” according to the Washington State Department of Transportation. It will then tunnel ahead about 450 feet before stopping just before it reaches the Alaskan Way Viaduct.
Related: Alaskan Way Viaduct will be closed in early 2016
The next phase of tunneling will allow crews to test the machine before it dives under the Alaskan Way Viaduct.
In March, Bertha is expected to bore under the viaduct. It will require a two week closure of the viaduct for safety.
The 6.5 feet Bertha moved Monday tacks on to the 8 feet the machine moved in December before crews went on vacation.
The machine has tunneled just over 1,000 feet of the 9,270-foot route from SoDo to South Lake Union.
