Latest updates on the Alaskan Way Viaduct Replacement Program
Crews removed more than 86,000 cubic yards of soil during construction of the recently completed SR 99 tunnel launch pit. That may seem like a lot, but it’s nothing compared with the 850,000 cubic yards of soil that will be removed by Bertha, the SR 99 tunneling machine, as she digs her way beneath Seattle.
How much is 850,000 cubic yards of soil? Put it this way: If, just for fun, you decided to pile it all on top of the turf at nearby CenturyLink Field, your pile would be … more
By now, drivers on State Route 99 near the stadiums are used to seeing large cranes and machinery near the spot where Bertha will start tunneling this summer. A crane is a crane is a crane, right?
Except when the crane in question is the Barnhart Modular Lift Tower, better known to most as the giant red crane that lowered many of Bertha’s 41 pieces into the pit where she’s getting ready to dig. Aside from having an impressively technical name, the modular lift tower, like … more
Suspended from a towering crane at the south end of downtown Seattle, the five-story-tall face of Bertha, the world’s largest tunneling machine, spent its last day above ground looking squarely at the old viaduct it was built to replace. Next stop: the 80-foot-deep launch pit where tunneling will start this summer.
Crews working with the Washington State Department of Transportation lowered Bertha’s 838-ton cutterhead into the launch pit today, ending eight weeks of heavy … more
Last spring, a field of unturned dirt marked the spot where Bertha will begin digging the two-mile State Route 99 tunnel beneath downtown Seattle. One year and 86,000 cubic yards of soil later, it’s a pit fit for the world’s largest tunneling machine.
Crews finished building Bertha’s 80-foot-deep launch pit on Sunday after nearly a year spent building its underground walls, removing soil and building the infrastructure needed to support the nearly 7,000-ton machine. Its … more
Last week, crews used a massive red crane to begin lowering the first large pieces of Bertha, the SR 99 tunneling machine, into the 80-foot-deep pit (pdf 485 kb) where she’ll start tunneling this summer. First up: the trailing gear, which will serve as Bertha's support system during tunneling by providing her with all of the equipment and materials she'll need to tunnel beneath downtown. The trailing gear accounts for much of the 326-foot-long machine's total … more
This week, crews will use a massive red crane to lower the first piece of Bertha, the SR 99 tunneling machine, into the 80-foot-deep pit (pdf 485 kb) where she’ll start tunneling this summer. Reassembling Bertha’s 41 pieces and testing the completed machine will take two to three months.
Crews from Hitachi Zosen, Bertha’s manufacturer, will assist throughout the process. Bertha won’t officially become the property of Seattle Tunnel Partners, WSDOT’s … more
Sixty years ago this week, Seattleites welcomed the State Route 99 Alaskan Way Viaduct to the city’s downtown waterfront. On Tuesday, April 2, the waterfront again welcomed a hulking guest: Bertha, the five-story-tall tunneling machine that will clear the way to the viaduct’s removal in 2016.
The ship carrying the machine that will dig the SR 99 tunnel beneath downtown Seattle entered Elliott Bay on Tuesday, April 2, after a two-week journey from the manufacturing plant in … more
The journey started today with a single ship. It will end about two weeks and 5,000 miles later in the waters of Elliott Bay, with the much-anticipated arrival of Bertha, the massive machine that will dig the SR 99 tunnel beneath downtown Seattle.
The five-story-tall machine left Osaka, Japan today aboard the Jumbo Fairpartner, the 475-foot-long vessel that will carry it across the Pacific Ocean. If the weather cooperates, the $80 million machine – which is owned by Seattle Tunnel … more
At first glance, the curvy temporary stretch of State Route 99 that opened last fall to the west of Seattle’s stadiums seems like an unusual path for a highway to take. Certainly it’s not the straightest line between two points. But viewed in a broader context – keeping the highway open during SR 99 tunnel construction – it’s most certainly the right path. It saves everyone in the long run by maintaining a vital route to and through downtown Seattle as we … more
Last month we reported that Bertha, the machine that will dig the SR 99 tunnel, was in the midst of an extensive testing program at the manufacturing plant in Japan. During testing crews discovered a problem with Bertha’s main-drive unit, which rotates the cutterhead at the front of the machine. She has since been partially disassembled so engineers could take a closer look at the issue.
The diagnosis? Bertha’s going to be just fine.
In fact, further examination of her … more