December 16, 2016

WSDOT updates state about its budget for building the tunnel

Photo by Benjamin Minnick [enlarge]

Bertha, decked out for the holidays, is about 70 percent finished digging the tunnel.

On Thursday, WSDOT gave the state Legislature’s Joint Transportation Committee an update on the Alaskan Way Viaduct replacement tunnel, where the boring machine named Bertha is about 70 percent complete with its mining.

There was some good news in the update: WSDOT’s proposed budget increase to cover delays associated with Bertha’s nearly two-year repair period is now $149 million, which is $74 million less than the last estimate in July.

That money is for things like additional contract administration and oversight, and extending leases with property owners around the tunnel route.

It doesn’t cover the cost of fixing Bertha. The tunnel’s design-build contractor, Seattle Tunnel Partners, has submitted a $480 million claim to WSDOT for that.

A WSDOT spokeswoman said STP’s claim is under review, but the agency contends that taxpayers won’t be responsible for the costs to repair Bertha.

A news release from WSDOT said: “We will continue to follow the tunnel project’s design-build contract to recover the added expense. This includes pursuing insurance claims, identifying potential cost savings in other elements of the program and ongoing litigation to recover damages. If efforts to recover costs are successful, the funds would likely not be available until after the project is complete.”

The news release attributed the revised $149 million budget request to having more information about the schedule and other facets of the $3.1 billion program, such as finding new efficiencies, performing a statistical risk analysis and updating cost estimates.

WSDOT said it was able to set aside contingency funding by recalculating the remaining risks and their potential costs. It said the biggest remaining risk is tunnel mining, which is expected to finish in June.

As of Thursday, Bertha had placed 1,014 rings for the 1,426-ring tunnel, and traveled 6,646 feet along its 9,270-foot route.

After Bertha breaks through the north portal of the tunnel, crews will spend months cutting up and removing the machine.

Construction of the double-deck highway inside the tunnel is expected to continue into 2018.

The tunnel is expected to open in early 2019, after which crews will begin to demolish the old viaduct and decommission the Battery Street Tunnel.

Bertha overheated in December 2013. The reason is in dispute: STP says Bertha overheated after hitting a metal pipe while WSDOT does not believe the 8-inch-wide steel well casing caused significant problems for the massive tunneling machine.

(Editor's note: The previous paragraph was changed, as the exact cause of the overheating has not been determined.)