Alaskan Way Viaduct | KUOW News and Information

Alaskan Way Viaduct

Members of Bertha's crew pose with the American flag after the SR 99 tunneling machine broke into her disassembly pit on April 4, 2017.
WSDOT

It’s over.

As dozens of people looked on Tuesday, Bertha broke through to daylight after a nearly two mile dig under Seattle that took almost four years. Seattle is one step closer to replacing the aging Alaskan Way viaduct and moving a two mile section of state route 99 underground. 


Updated at 4 p.m. ET

It was the world's biggest tunneling machine when it first chewed into the loose dirt and gravel on Seattle's waterfront in 2013. With a cutting head nearly 60 feet wide, it had been built in Japan and shipped across the Pacific to dig a two-mile-long double-decker highway tunnel under downtown.

The machine was named "Bertha" in honor of a 1920s-era mayor — the prefatory "Big" always implied, never stated.

A view to the back end of Bertha, the SR 99 tunneling machine. The steel hooks on both sides of the wall of the tunnel will become part of the foundation that will support the decks and walls of the future roadway, according to the state.
Flickr Photo/Washington State Department of Transportation

Bertha has stopped again, but this time, it’s on purpose.

The tunnel boring machine rests in an underground concrete vault. Workers are putting the tunnel boring machine through complex tests before it pushes under the Alaskan Way Viaduct. 

City of Seattle Office of the Waterfront

A proposal to upend the official city waterfront plan and preserve a chunk of the Alaskan Way Viaduct as an elevated park isn’t sitting well with former Seattle Mayor Charlie Royer.

“These are being treated like competing proposals in the media, and they are in no way competing proposals,” Royer told KUOW’s Ross Reynolds of the Park My Viaduct initiative.

This July 2015 photo shows the SR 99 tunneling machine’s main bearing encircled by the gear ring that facilitates rotation of the cutterhead.
Washington State Department of Transportation

Bertha, the giant tunnel boring machine stalled in downtown Seattle, remains in pieces at the foot of the Alaskan Way Viaduct.

Alaskan Way viaduct, Seattle waterfront, downtown
Flickr Photo/WSDOT (CC-BY-NC-ND)

What do sagging buildings and a slumping viaduct mean for Seattle's waterfront tunnel? Would you rather pay a gas tax, or let a GPS tracker charge you by the mile? Are Paul Allen and Bill Gates shaping Seattle, or did we shape them first?

Bill Radke covers the week’s top stories with guests Knute Berger, Joni Balter and Northwest News Network’s Phyllis Fletcher.

The Alaskan Way Viaduct sank 1.25 inches in November, prompting state officials to consider stopping a water pumping project nearby.
Flickr Photo/camknows (CC-BY-NC-ND)

The Alaskan Way Viaduct is safe to drive on, state officials told the Seattle City Council on Monday afternoon. That follows the weekend’s news that the viaduct may be sinking more than expected.

Just west of the viaduct, a giant wood and metal wall shielded public viewing of a giant pit where Bertha, a boring drill, has been stuck for nearly a year. Bertha is supposed to bore through Seattle, creating a tunnel to replace the Viaduct.

Flickr Photo/Nantaskart!

One of the two companies attempting to dig a highway tunnel beneath the Seattle waterfront has won an $80 million dispute with the Massachusetts Department of Transportation.

Seattle Mayor Ed Murray in the KUOW studios.
KUOW Photo/Bond Huberman

Marcie Sillman talks with Seattle Mayor Ed Murray about restoring the Seattle Police Department's reputation, new cracks in the Alaskan Way Viaduct and the latest progress on the minimum wage debate.

Courtesy of Museum of History & Industry

Historians point to the early months of 1852 as the time that downtown Seattle was founded. One Sunday in late winter of that year, members of the Denny Party, a group of settlers from Illinois who’d arrived at Alki a few months earlier, paddled across Elliott Bay.

KUOW/John Ryan

Seattle's tunnel builders say getting their world-record tunnel machine going again will take at least six more months.

The tunnel machine known as Bertha has sat largely motionless for nearly three months since it overheated in early December.

The Alaskan Way Viaduct sank 1.25 inches in November, prompting state officials to consider stopping a water pumping project nearby.
Flickr Photo/camknows (CC-BY-NC-ND)

Anyone who's hosted a party has probably had that panicky feeling beforehand: What if you throw a big party and nobody comes?

State transportation officials face a similar worry: What if after they build a $3.1 billion underground highway to replace the Alaskan Way Viaduct, not enough people use it?

Build It And They Won't Come?

The state Legislature has decreed that tolls have to pay for $200 million of the state Route 99 tunnel's construction cost.

Progress at last on the tunnel being built to replace the Alaskan Way Viaduct.
Flickr Photo/Washington State Department of Transportation CC BY-NC-ND 2.0)

Marcie Sillman talks with state transportation secretary Lynn Peterson about Bertha's latest condition and plans to get the world’s biggest tunnel boring machine moving again.

KUOW Photo/John Ryan

State officials said Friday afternoon that the tunneling machine known as Bertha had to stop, not because it hit foreign objects, but because it clogged with dirt.

KUOW Photo/John Ryan

To get Bertha moving again, state officials announced Wednesday that they are sending in human reinforcements – in a giant, pressurized bubble.

Anything But Boring: Bertha Updates

Jan 9, 2014
Two workers walk through the first rings of the tunnel toward Bertha, the SR 99 tunneling machine.
Flickr Photo/WSDOT (CC-BY-NC-ND)

Ross Reynolds gets an update from WSDOT Highway 99 Program Administrator Matt Preedy on how and when Bertha will move forward, and who is going to pay for it.

SDOT Projects Depend Upon Bertha's Advance

Jan 3, 2014
Progress at last on the tunnel being built to replace the Alaskan Way Viaduct.
Flickr Photo/Washington State Department of Transportation CC BY-NC-ND 2.0)

Marcie Sillman talks with Jon Layzer, director of major projects for the Seattle Department of Transportation, about how city capital projects are intricately connected to the Alaskan Way Viaduct Replacement Program.

Flickr Photo/Tender Young Pony of Insomnia

Marcie Sillman talks with Jennifer Ott of HistoryLink.org about one possible cause of the SR 99 tunneling machine’s blockage: leftovers from Seattle's historical waterfront development.

For other, more humorous, theories check out our What's Blocking Bertha? compilation.

What's In Bertha's Way?

Dec 10, 2013
Flickr Photo/WSDOT (CC-BY-NC-ND)

Marcie Sillman talks with Seattle Times transportation reporter Mike Lindblom about what may have halted Bertha, the huge tunneling machine in charge of digging the new SR 99 tunnel.

In their first televised debate on KING5 TV, Mayor Mike McGinn and State Senator Ed Murray engaged in a sharp but mostly civil exchange over housing, transportation, and police reform, among other things. 

Flickr Photo/WSDOT

A new tolling proposal would ask drivers to pay as little as $1.00 for taking the Highway 99 tunnel under downtown Seattle. During morning and evening commutes, rates would jump to $1.25. A state advisory committee is hoping the proposal will strike a balance between tolling revenues and potential traffic diversion.

Two years ago, when the tunnel plan was approved by voters, the proposed tolling rates were as high as $3.00 during peak hours. Under that plan, traffic planners were concerned that high tolling rates would divert too many cars onto downtown streets. Maud Daudon is co-chair of the Advisory Committee on Tolling and Traffic Management. She's also president and CEO of the Seattle Metropolitan Chamber of Commerce. She talked with Ross Reynolds.