As Washington State Dept. of Transportation officials look toward a fall 2018 opening of the 1.7-mile-long bored tunnel under downtown Seattle that will replace the aging 1953-opened Alaskan Way Viaduct, the final contract in the $3.3-billion project to tear down the viaduct was awarded to Kiewit Infrastructure West.
The nearly $3.3-billion Alaskan Way Viaduct Replacement Project is set to finish this year, potentially, after crews overcame a saga of challenges and delays.
The Alaskan Way Viaduct Replacement Tunnel was originally slated to open in December 2015, but faced years of delays when the tunnel-boring machine malfunctioned beneath downtown Seattle.
As we move closer to the 2019 milestone of opening the new State Route 99 tunnel under downtown Seattle, officials can start making plans for removal of the aging Alaskan Way Viaduct, the entire reason the new 1.7-mile tunnel was conceived originally.
For anyone wanting to get a peak under the shield of Bertha, the 57.5-ft-diameter tunnel-boring machine that dug a 1.7-mile tunnel under downtown Seattle, now is the time.
After a final, Feb. 28-March 6 maintenance stop, the world’s largest-diameter tunnel-boring machine has moved less than two blocks away from the disassembly pit in Seattle. TBM “Bertha,” churning a 1.7- mile-long tunnel for a state Route 99 replacement of the Alaskan Way Viaduct, required a stop less than 1,000 ft from the pit to confirm that the 57.5-ft-dia machine was 6 in. off course alignment.
