On Thursday January 14th, Washington State Gov. Jay Inslee ordered Bertha, the Worlds Largest Tunnel Boring machine, to stop drilling the SR99 tunnel beneath the streets of Seattle.
This followed two back-to-back incidents created by the dig.
Thank God we have a Democrat governor. Who knows what a "Republican Rick Snyder - type Governor," who has been poisoning the residents of Flint, would have not done?
■ First incident. On Tuesday January 12th, a spoils barge began tipping over whilst being loaded at the Pier 47 loading site. A bulkhead collapsed, spilling spoils into Elliot Bay.
Instead of hauling up to 5,000 tons of the tunneling spoils away each day in a fleet of trucks, Seattle Tunnel Partners inked an agreement with Foss Maritime (Seattle), to move up to
twice that amount in barges.
Pier 47 sustained considerable damage to pilings. Pier 48, where the barge drifted following its release also sustained damages. (WSDOT purchased the pier and it was scheduled for demolition.)
Spoils from the Tunnel Boring Machine travel on a conveyor belt, through the completed bore, across former Alaskan Way, to a site on Pier 47.
Foss Maritime has the concession to transport the spoils to an abandoned rock quarry located near Mats-Mats on the Kitsap Peninsula.
■ Second incident. Hours later, following the barge accident,
a sink hole opened up behind the Tunnel Boring Machine. I measured 35 feet long, 20 to 25 feet wide and 15 feet deep, sucking up ~250 cubic yards of dirt!
The emergence of the sink hole sent alarms through the Department of Transportation. Smelling potential law suites against the City of Seattle, and the State of Washington, Governor Jay Inslee directed Seattle Tunnel Partners cease boring. Stop Bertha in her tracks!
Washington State Secretary of Transportation, Lynn Peterson, requested Seattle Tunnel Partners shut the Tunnel Boring Machine down.
"I have great concerns regarding public safety if the contractor were to move forward without addressing the root causes of this sinkhole," Governor Inslee said during a news conference.
"We must continue to protect the public safety."
This following a two year delay, during which a 100 foot deep rescue pit had to be constructed, the TBM driven into the pit and dismantled. Crews spent months repairing and replacing components of the complex machine.
Finally on December 13th crews began filling the repair pit, burying Bertha beneath tons of sand. Eight days later on December 20th, the sand back-fill was completed at 2 a.m.
Within minutes, at 2:13 a.m., concrete pumping trucks were in place, pouring a concrete plug atop the sand. 14 hours later, the concrete plug was complete at 4:05 p.m.
Bertha broke out of the rescue pit, and had advanced a short distance before the sink hole appeared.
The only activity on site today is the disassembly of the massive Mammoet Hydraulic Jack Lifting Device.
The project is sadly behind schedule. Should work continue, this highly detailed interactive graphic, produced by WSDOT (Washington State Department of Transportation), offers an optimistic view of what lies ahead for Bertha.
There are
many moving pieces in this presentation. As a retired Instructional Designer,
I award 10 out of 10 points for instructional value! Take your time to absorb the content of this interactive graphic.
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| Courtesy, Sightline.org |
Back in December, 2013, as the first pieces of Bertha were being hoisted to the surface for repairs, Washington Governor Inslee told an assemblage,
"There's no plan B if Bertha tunnel project fails."
While it may be true that the
State has no "Plan B" in the event of a catastrophic failure of Bertha, inventive citizens have worked up very
clever and creative uses for the existing tunnel, terminating with a majestic Community Hall and atrium, featuring an awe-inspiring view of Bertha, the Worlds Largest Tunnel Boring Machine.
And, of course, you'll be able to pose for photos in front of the massive 5-story high cutter head:
Bertha Viewing Gallery
• Adults — $15.00
• Seniors / Military — $7.00
• Children under 10 — Free!
1 Comments - Click here:
Interesting that the sink hole was so close to the rescue pit.
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