Thousands of sensors will check for movement as Bertha digs under viaduct

SEATTLE --The two-week closure of the Alaskan Way Viaduct begins Friday, and drivers across the area are bracing for traffic gridlock.

The tunnel-boring machine is in the process of replacing the Alaskan Way Viaduct.

Starting Friday, Bertha will dig directly beneath the viaduct and will have to get through about 350 feet for this phase of the project.

The Washington State Department of Transportation has hired a contractor called Soldata to monitor Bertha's dig.

Thousands of sensors both underground and on buildings along a two-mile stretch downtown will pick up any movement as Bertha digs just 15 feet below the foundation that supports the viaduct.

As for traffic, WSDOT, the Seattle Department of Transportation and the Seattle Police Department will all be working in conjunction to keep traffic moving.

“We will be monitoring our cameras on the key corridors where we expect traffic to be the worst,” Jon Layzer with SDOT said.

SDOT is bracing for heavy traffic on Seattle's surface streets as 90,000 vehicles find alternate routes. They will use electronic signs to keep drivers alert and tweak traffic signal times if they have to.

“I’ll definitely avoid going that way during peak traffic,” one driver said.

It’s not just Seattle; the gridlock will be region-wide, stretching up and down I-5, I-405 and the bridges connecting Seattle to the Eastside. For many, the traffic nightmare is unavoidable.

“The first thing I would do is look into biking and taking public transportation,” motorcyclist Larry Hudson said.

Hudson says he's working from home but feels bad for the people who don’t have that option. He says the only answer on the first day of the closure is to leave your house two hours earlier.

Drivers are hoping Bertha's dig will take no longer than the two weeks projected by WSDOT.

Q13 News asked WSDOT about the state's long-term plan in case something goes wrong, such as Bertha getting stuck underneath the viaduct.

Could WSDOT reopen the viaduct even if Bertha is stuck? A spokesperson on Monday said a response would be speculative and the answer would all depend on the exact problem that arises.

“I hope the answer isn’t funneling people onto the surface street down there,” Hudson said.