World’s largest diameter TBM gets a name
January 15, 2013
The world’s largest-diameter tunnelling machine, which will begin boring the SR 99 tunnel beneath downtown Seattle next summer, now has a name, the Washington State Department of Transportation (WSDOT) announced recently. Following a competition to name the machine, the winning entry was Bertha.
Bertha's name was chosen as part of a contest for kindergarten through 12th grade students. Proposed names had to be female and have significance to Washington state heritage, life, nature, transportation or engineering.
"This project is about breaking new ground," said Charley Royer, former mayor of Seattle and a contest judge. "Like the SR 99 tunnelling machine, Bertha Knight Landes was one of a kind. It's only fitting that the machine bears her name."
The winning name was submitted by two entrants: Darryl Elves' fifth-grade class at Poulsbo Elementary School and Elijah Beerbower, a second-grader at Lincoln Elementary School in Hoquiam. All of the winners will be invited to Bertha's dedication ceremony in Seattle next summer. They will also receive special t-shirts and the honor of having the name they chose painted on the side of the machine.
WSDOT added that crews in Japan are putting the finishing touches on the machine. They recently installed its 57.5ft (17.5m) diameter cutterhead. Bertha will officially become the property of WSDOT's contractor, Seattle Tunnel Partners, in late December. She'll then be disassembled and loaded onto a ship scheduled to arrive in Seattle next spring. Tunnelling will start next summer to the west of Seattle's stadiums, where crews are currently building the massive pit down which the machine will begin its underground journey.