Alaskan Way Viaduct2018-02-21T16:53:00-08:00

The Alaskan Way Viaduct

This $3.2 billion Seattle project is actually a collection of 32 individual projects that launched in 2010 to replace an outdated section of State Route 99. The most famous part is the 2-mile-long tunnel dug by the “Bertha” drill, which started burrowing into the Seattle soil in summer 2013. After a two-year delay to diagnose and repair technical troubles with the drill, Bertha finished tunneling on April 4, 2017. State and local government officials estimate the entire project will be completed in 2023.

Crews start moving Bertha’s rebuilt cutter drive back into pit

The Seattle Times » The boring machine, nicknamed Bertha, is expected to resume digging by November 2015, two years after she overheated and stalled. Additional teeth, improved seals, and 86 tons of reinforced plates have been added, along with longer arms and fins to loosen the ground as Bertha digs. The Alaskan Way Viaduct is expected to open in March 2018. So far, the Washington State Department of Transportation (WSDOT) has paid $1.04 billion to the Seattle Tunnel Partners (STP) on the $1.35 billion design-build contract, and Bertha’s manufacturer, Hitachi-Zosen, has covered the multi-million dollar repair cost.

August 27, 2015|

Water main damaged by tunnel project to be replaced

The Seattle Times » Crews will be digging up Western Avenue in the Pioneer Square neighborhood to replace one quarter-mile section of the city’s water main that was damaged during the Highway 99 Tunnel Project. The cast-iron water main, connected by lead footings, has sunk as much as 1.3 inches in some places. The suspected cause is ground water pumping that was being performed to help crews reach and repair a damaged tunnel boring machine.

April 13, 2015|

Transportation officials: New cracks on Alaskan Way Viaduct

Associated Press/Komo News 4 » Seattle’s tunnel project is two years behind schedule and now expected to cost $3.1 billion, according to a report by the Washington State Department of Transportation (WSDOT). An inspection at the end of March 2015 found new cracks on the existing Alaskan Way Viaduct near the site where the tunnel boring machine known as Bertha is being repaired by the Seattle Tunnel Partners.

April 7, 2015|

Stuck in Seattle: The Aggravating Adventures of a Gigantic Tunnel Drill

Bloomberg » The State Route (SR) 99 Alaskan Way Viaduct Project is a $4.2 billion effort to restore the view of Seattle’s waterfront by building a two-level underground highway. Tunnel construction is being done through a design-build (D/B) agreement between the Washington State Department of Transportation (WSDOT) and Seattle Tunnel Partners, a joint venture of Tutor Perini and Dragados USA. The tunnel project was estimated to cost $1.4 billion with completion expected by November 2015. However, the Bertha boring machine stalled in 2013 with $125 million in projected repair costs. This article details the project’s development through Bertha’s breakdown and recent rescue.

March 31, 2015|

WSDOT: Ready to restart Bertha this week

Q13 Fox/Associated Press » The Washington State Department of Transportation (WSDOT) announces Bertha is almost ready to resume digging.

February 15, 2015|
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