One of the two Highway 99 tunnel prime contractors says it will appeal Friday’s jury verdict that rejected the companies’ $330 million in claims against Washington state over the breakdown of tunnel-boring machine Bertha six years ago.

Seattle Tunnel Partners (STP) has argued that a 110-foot-long steel pipe which Bertha hit Dec. 3, 2013, caused the breakdown. That pipe had been installed for groundwater testing by the Washington State Department of Transportation in 2002, during preliminary engineering for the Alaskan Way Viaduct replacement project.

STP member Tutor Perini Corp., which has a long record of litigation, said in an announcement to investors that it “is disappointed with the jury’s decision and will appeal the verdict in this case…”

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The statement emphasized a 2015 finding by the project’s dispute-review board, composed of three tunneling experts, that the pipe constituted a “differing site condition” for which the state was responsible to solve or alert contractors. The board, whose views are nonbinding, didn’t opine about how much damage the pipe caused.

At the trial, in Thurston County Superior Court, WSDOT’s attorney called the pipe “nothing more than a toothpick” for Bertha’s massive cutter head, while STP argued the machine made steady progress except three days immediately after hitting the pipe.

In the buildup to the two-month trial, WSDOT attorneys uncovered documents showing that tunnel workers encountered and logged the pipe before digging began.


Tutor Perini filed an official investor notice this fall asserting that its odds of winning state or insurance money are “both probable and reliably estimable,” and that management made its own confidential prediction of what the partners will recover, beyond the $1.44 billion contract that’s nearly all been paid.

The four-lane tunnel opened for traffic this Feb. 4, to replace the old Alaskan Way Viaduct. STP executives haven’t yet responded to Seattle Times requests for comment.

Not only did jurors reject STP’s claim, but they awarded the state $57.2 million from the contractors based on 867 days of delay, while Bertha was exhumed from soggy waterfront soils and repaired.

State Transportation Secretary Roger Millar on Friday said he anticipates an appeal, so he hasn’t earmarked the $57.2 million yet toward other projects.