After years of planning and months of work, the world’s largest tunneling machine was sinking its teeth into the soil Tuesday to drill a new route for state Route 99 under downtown buildings, the Washington Transportation Department said.
“Today is the day,” spokeswoman KaDeena Yerkan said. “Everyone here is very excited. We’ve been planning for this for many years. It’s nice to see we’re going to start digging under the city and get the project moving.”
The tunnel will go under about 200 buildings, but officials don’t expect any serious problems from the machine they call Bertha.
“We know exactly the path of Bertha and what she’ll encounter along the way,” Yerkan said.
The tunneling crew will be monitoring for settling and vibrations and is prepared to keep building foundations secure.
“So we’re not worried buildings are going to tip,” she said.
Bertha is 326 feet long and weighs 7,000 tons. It will leave a tunnel nearly 58 feet in diameter.The Associated Press