SEATTLE — Contractors hope the tunnel machine Bertha, which has been stalled for more than two years digging a new State Route 99 tunnel beneath Downtown Seattle, will resume drilling on Monday.
On Thursday, Chris Dixon of Seattle Tunnel Partners, told state lawmakers that advancing Bertha through the sand and dirt inside the machine’s repair pit will be the final phase of the testing process before the dig resumes in earnest after the New Year.
Dixon hopes the machine will advance far enough before December 23 to lay three concrete rings of the new tunnel.
Dixon expects the machine to break through the wall of the repair pit and resume the main part of the tunnel drive after workers return from a holiday break, which will run from December 24 to January 4.
In January, Bertha will advance about 450 feet to a previously fortified area where the machine will be inspected. The next step will be to tunnel beneath the Alaskan Way Viaduct. According to the contractor’s schedule, which state officials do not verify, that could come in March. The Washington State Department of Transportation expects to close the viaduct to traffic for up to two weeks when Bertha drills beneath it.
Most Seattleites remember the day in December 2013 when Bertha stopped.
Here’s a Q&A refresher on what went so wrong with Bertha, how much it costs, and what happens next.
Why did Bertha come to a halt?
The cause of the breakdown is under investigation and will likely be at the center of a legal dispute between state officials and the contractor over liability.
The machine's cutting teeth struck a 119 foot pipe, eight inches in diameter, on December 3, 2013.
The machine overheated and came to a halt three days later. In investigating the overheating, contractors discovered the cutter head was clogged and found pieces of the pipe. A subsequent investigation discovered damage to the seal system protecting the main bearing.
The pipe was a steel well casing installed by a previous contractor for WSDOT and its role in Bertha’s problems is in dispute.
In 2014, contractors suggested that chewing through the pipe set off a chain reaction that led to the breakdown.
In 2014, state officials suggested there might have been other factors, such as the machine being operated incorrectly, that contributed to the machine overheating.
Another theory is that problems re-surfaced that were first identified during testing in Japan by Bertha’s manufacturer, Hitachi-Zosen.
“When someone tells you what they think caused the damage you're only hearing one of six or seven causation theories that were out there,” Chris Dixon of Seattle Tunnel Partners told the Seattle City Council in December 2015.
WSDOT contends the steel pipe was well documented in material it provided to STP. STP contends it was not properly warned about the pipe, and requested $125 million in additional compensation related to the breakdown. WSDOT denied that request.
Who is in charge of the tunnel project?
The project was initiated by Washington’s previous Governor Chris Gregoire.
The Washington State Department of Transportation is working with Seattle Tunnel Partners (STP), a consortium of Dragados USA and Tutor Perini.
How much progress has Bertha made?
Bertha tunneled 1,023 feet before becoming stranded underground. The entire tunnel drive from SODO to South Lake Union will be 1.7 miles.
Workers then had to dig an access pit in front of Bertha to pull major components above ground for repairs.
Contractors successfully lifted the machine's cutter head and drive unit out of a 120-foot pit in March 2015.
STP and manufacturer Hitachi Zosen spent most of the rest of the year fixing the machine and then lowered it back down into the pit.
WSDOT released video of the cutter head rotating in a test on Nov. 24, 2015.
When will the tunnel machine finish its trip under Seattle and break-through to the other side?
January 2017 is the new anticipated break-through date, according to the contractor’s schedule. April 2018 is when the tunnel is supposed to open for traffic.
Why so many restart dates?
After the halt, STP initially announced September 2014 as a restart, then pushed it back several times. Building the access pit and the repair effort itself proved complicated.
When was the tunnel supposed to open?
According to the contract with STP, the four-lane toll tunnel was supposed to open to traffic at the end of 2015.
How much money is being lost?
WSDOT says it expects to lose $78 million, according to insurance fillings.
The $78 million cost reflects extra spending on administrators, engineers, consulting firms and office space associated with a two-year delay.
An expert review panel, hired by the Washington Legislature, made a worst-case prediction in April 2015 that Bertha's breakdown will cost the state $317.5 million.
The panel also identified $329.6 million in potential funding to cover those costs.
They include $124.2 million in contingency funds, $50.4 million in penalties from STP for delivering the tunnel late, $85 million in insurance payments and $70 million in savings on projects after the tunnel is done that the state thinks will cost less than first expected.
"From what we know today, those issues could be resolved with the funds currently available within the program budget," panel chair Patricia Galloway told KIRO 7.
Soon after that report, state legislators declined to extend the contract for the expert review panel, fearing that its access to both WSDOT and STP could put the state at risk in future litigation.
The overall program budget for replacing the viaduct is $3.1 billion and the value of the contract with STP is $1.35 billion.
What does this mean for taxpayers?
Despite the expensive breakdown, taxpayers might not be on the hook for extra money. Read the full report released in April for the reason why.
Separately, WSDOT filed a lawsuit against STP in October:
“Filing this lawsuit ensures WSDOT will have a right to make legal claims in the future. This lawsuit does not prevent STP from pursuing claims under the terms of the design-build contract,” WSDOT said in a statement.
WSDOT says the design-build nature of its contract with STP protects taxpayers because the contractor and Bertha’s manufacturer are on the hook for the cost of repairs.
KIRO
